It is Now Time to Vote

The April issue of the Bulletinannounces the candidates for the HGS officers and Board of Directors for 2014-15 and members of the AAPG House of Delegates for 2014-17. [Editor’s NotE: Candidate profiles for the AAPG House of Delegates will appear in the May issue of the HGS Bulletin.] First let me thank each of the candidates for stepping forward to take on their respective tasks, which include guiding our organization forward and representing the Houston Geologic Society as part of AAPG’s deliberative body. I now ask that each of you take a few minutes and read the biographical material and reasons that each candidate has provided to explain their decision to stand for office, followed by the important act of submitting your vote. Your participation in the voting process remains an important part of the success and future of both organizations.

Over the years, the HGS has grown significantly. The Society’s annual budget now exceeds $1,000,000. The organization has expanded its office space and now has three full-time employees. From September through June, there may be as many as six monthly meetings organized by the Society. HGS continues to print a hard-copy magazine style monthly Bulletin. In addition, HGS now organizes at least two conferences each year, with international participation, as well as a number of short courses. The Society continues to be active in guaranteeing the future of our science and profession by supporting two funds which grant undergraduate and graduate scholarships. We also continue to support the Science and Engineering Fair of Houston, as well as Earth Science Week each year, and have approved a contribution toward an endowment that will guarantee long-term survival of the Science Fair. The Society also maintains several members’ social programs, such as the Tennis, Golf, and Skeet tournaments, as well as Guest Night.

As HGS moves forward, it has a number of key challenges. As President, I recognize that there are at least two major challenges that the incoming Boards will need to address over the next few years. The first is membership growth and the need to shift the demographics of the Society. Earlier this year, we had a very successful drive to recover lost members. In 2013, the change in the Society’s website introduced a number of problems in accepting payments. Members became frustrated and did not renew. The website problem, which has been corrected, resulted in a “loss” of more than 2000 active members. The good news is that more than half have returned. The bad news is that we still lost a significant number of our members. New member applications remain steady each month, but could be significantly greater, especially as the “Great Crew Change” begins to increase its pace and the need increases for members that are new to our profession.

Future Boards will need to take on the challenge of finding a way to entice the young professional to join HGS. This will require a fresh approach to this challenge that has persisted for several years. The second challenge is a matter of ensuring that the volunteer pool is renewed. Many of our committees have been chaired and staffed by the same volunteers for multiple years. Although they continue to do an exceptional job, we cannot expect that this will continue indefinitely. Ensuring succession plans for committee chairs and committee membership will be high on the list of the 2014-15 Board’s work. They will need to ensure that new people volunteer and that they are successfully mentored, making sure that the job responsibilities and work plans for each committee and position are documented. If HGS lacks an informed volunteer pool to run an activity, that program may disappear. Your vote for the HGS officers is the first step in ensuring that these programs move forward and that the key challenges for the Society are overcome.

The new members of the AAPG House of Delegates (HOD) will also have some key issues to deal with as the AAPG examines its future. The AAPG shares some of the same problems with HGS, such as membership, and others that result from its international footprint and the need to provide products and services to a global membership pool with the associated overhead costs. A number of governance issues will be presented to the HOD for debate and approval. These proposals could change the future of the organization. Individuals will need to consider how the various proposals may impact the overall organization and not just their own individual circumstances. The individuals we select for these positions will need to be those that we trust with the future of the AAPG as it enters into a time of potential transition.

Once again, let me ask that you read about the candidates and vote with an understanding that the future of two organizations rests with that vote. Remember “elections have consequences,” even those of professional societies.

Also, remember to join us this month at the George R. Brown Convention Center for the AAPG Annual Convention and Exhibition. It will be an opportunity to maintain, develop, and expand those all-important professional networks and to continue our education. A review of the technical program suggests that it will be outstanding.

Until next time...

Snowball Earth: Frozen Oceans and Greenhouse Gases

Residents of the eastern half of the United States endured months of bone-chilling cold, coatings of ice, and deep snow drifts during the first few months of 2014 due to a “polar vortex.” Yet the polar vortex ebbed allowing the return of more seasonable and temperate conditions. The residents of the supercontinent Rodinia were not so fortunate. According to plate tectonic reconstructions, Rodinia existed between 1.1 billion and 750 million years ago. Several times the Earth’s global mean temperature plunged to less than 75 degrees below zero Fahrenheit, freezing over all of the world’s oceans and shrouding the entire globe from pole to pole in a cloak of ice. Researchers have dubbed these episodes “Snowball Earth.”

The most notable, and perhaps last, global freezing event occurred approximately 650 to 635 million years ago during the Marinoan Epoch glaciation toward the end of the Cryogenian period (850 to 635 million years ago) in the Neoproterozoic era (approximately 1 billion to 542 million years ago). Some researchers, including a team led by Huiming Bao, Charles L. Jones professor in geology and geophysics at Louisiana State University, contend that this last period of extensive glaciation and the subsequent climate changes might have given rise to modern levels of atmospheric oxygen. This set the stage for the rise of animals and the later explosive diversification of life forms during the episode called the Cambrian explosion.

The Snowball Earth concept posits that, during these exceptional cold events, the atmosphere was prevented from warming because most of the incoming solar radiation was reflected back into space by the whiteness of ice and snow covering the oceans and land surface. A lack of heat-retaining clouds and atmospheric moisture, caused by water vapor freezing out of the atmosphere, further amplified this effect. This resulted in average equatorial temperatures of about minus 10 degrees Fahrenheit, roughly similar to presentday conditions in Antarctica. Without the moderating effect of open oceans, the Earth’s climate became much like that of Mars. However, due to some atmospheric sublimation (ice to vapor) and condensation, snow would continue to fall, glaciers would thicken and flow, and sedimentary deposits of glacial origin would be left behind as geological evidence of these severe conditions.

In a January 2000 Scientific Americanarticle titled, “Snowball Earth,” the authors Paul F. Hoffman and Daniel P. Schrag describe evidence from extreme icing events that occured as many as four times between 750 and 580 million years ago during the Neoproterozoic era. These icing events continued into the Ediacaran period (roughly 635-542 million years ago). The Ediacaran, the last period of the Neoproterozic, immediately precedes the Cambrian period of the Paleozoic. The Ediacaran period, named after the Ediacara Hills of South Australia, had its status as an official geological period ratified in 2004 by the International Union of Geological Sciences (IUGS), making it the first new geological period declared in 120 years.

Concept Origins
Thick geological deposits hold the only clues to the climate of the Neoproterozoic. For decades, many of those clues were riddled with contradictions. The foremost paradox was the occurrence of glacial debris in sediments deposited near sea level in the tropics. As observed in the January 2000 Scientific Americanarticle, glaciers near the equator today occur only above about 15,000 feet above sea level. Even during the ice ages of the Pleistocene, glaciers reached no lower than 12,000 feet in low-latitude areas. Mixed in with the Neoproterozoic glacial debris are unusual deposits of iron-rich rock which could form only if the oceans and atmosphere contained little or no oxygen, even though by that time the atmosphere had already evolved to nearly the same mixture of gases as it has today. To confound matters, thick carbonate rock sequences, typical of deposition in warm seas, were observed to have been deposited on glacial deposits shortly after the ice receded.

Many geologists have grappled with these puzzling low-latitude glacial deposits. One of the earliest was the Australian geologist and Antarctic explorer Douglas Mawson (1882–1958). Sir Mawson, a Fellow of the Royal Society, on the first team to ascend Mount Erebus, Antarctica’s tallest peak, and on the first team to reach the magnetic South Pole, spent much of his career studying the Neoproterozoic stratigraphy of South Australia where he identified thick and extensive glacial sediments. Late in his career, he speculated about the possibility of global glaciations. However, his ideas of global glaciation were hampered by the mistaken assumption that the geographic positions of Australia, and all the other continents were fixed in their present positions. Not until the development of the plate tectonic theory could geologists see the whole picture of lowlatitude glacial deposits.

In 1964, the idea of global-scale glaciation reemerged when W. Brian Harland (1917 – 2003) published the paper “Critical evidence for a great infraCambrian glaciation” in the International Journal of Earth Sciences. In the paper, Dr. Harland presented paleomagnetic data showing that glacial tillites in Svalbard and Greenland were deposited at tropical latitudes. Based on the paleomagnetic data and the sedimentological evidence of glacial deposits interrupting successions of carbonate rocks commonly associated with tropical to temperate latitudes, he argued for an extreme ice age affecting the tropical regions.

Also in the 1960s, Mikhail Budyko (1920 – 2001), a Russian climatologist at the Leningrad Geophysical Observatory, developed an energy-balance climate model to investigate the effect of ice cover on global climate. Using this model, Dr. Budyko found that if ice sheets advanced far enough beyond the polar regions, to roughly 30 degrees of latitude, a feedback loop developed due to the increased reflectiveness of the ice and snow. The reflectiveness of ice and snow is known as albedo (see the text box). The increased reflectiveness returns the incoming solar energy into space and prevents the Earth’s surface from warming. This leads to further cooling and the formation of more ice, until the entire Earth was enveloped in ice and stabilized in a new ice-covered equilibrium in a run-away icehouse effect. While Dr. Budyko’s model suggested that this shift to an ice-albedo stability could happen, he concluded that it had never happened, because his model offered no way for the Earth to escape from scenario of perpetual deep freeze.

The moniker “Snowball Earth” was coined by Joseph Kirschvink, a professor of geobiology at the California Institute of Technology, in a paper titled “Late Proterozoic low-latitude global glaciation: the Snowball Earth” published in a multidisciplinary study by the Cambridge University Press in 1992. The major contributions from this work were: (1) recognition that the presence of banded iron formations is consistent with a glacial episode where the atmosphere is depleted in oxygen and (2) introduction of a mechanism with which the Earth could escape from an ice-covered condition. This mechanism is the increasing accumulation of atmospheric carbon dioxide (CO2) from volcanic outgassing leading to an ultra-greenhouse effect.

The Snowball Earth hypothesis was brought to widespread attention in the scientific community by the publication of “A Neoproterozoic Snowball Earth,” by Paul F. Hoffman, Alan J. Kaufman, Galen P. Halverson, and Daniel P. Schrag in the August 1998 issue of the journal Science. Dr. Hoffman, professor of geology at Harvard University, and his coauthors studied carbon isotope anomalies in carbonate rocks bracketing Neoproterozoic glacial deposits in Namibia. These glacial deposits included ice-rafted dropstones in equatorial marine strata. The authors combined their observations related to these anomalies with estimates of thermal subsidence history to develop the conclusion that biological productivity in the surface oceans collapsed for millions of years. They explained the collapse as related to ice-covered seas during global glaciations, that is, a snowball Earth. The authors went on to posit that these glacial episodes ended abruptly when subaerial volcanic outgassing raised atmospheric carbon dioxide concentrations to about 350 times greater than modern atmospheric concentrations. The increased carbon dioxide concentrations resulted in a rapid warming due to extreme greenhouse conditions. Additionally, the transfer of atmospheric carbon dioxide to the ocean resulted in the rapid precipitation of calcium carbonate in warming surface waters, producing the carbonate rocks observed globally capping the Neoproterozoic glacial deposits.

How did it Happen?
While geological evidence of Neoproterozoic glaciations is strong, a thorough understanding of the mechanisms that caused the extreme temperature plunge is incomplete. Current thinking is that a reduction in the concentration of “greenhouse” gases, particularly carbon dioxide and methane, led to a globally colder climate. The colder climate allowed areas of ice to expand from the polar regions into lower latitudes. Researchers theorize that when the earth became approximately 50 percent covered by ice, the global climate reached a tipping point where the solar radiation was no longer able to warm the Earth surface due to the increased albedo leading to a runaway icehouse effect.

But what caused the lowering of atmospheric concentrations of the greenhouse gases? CO2 cycles through the atmosphere and ocean starting with volcanic emanations and ending with removal as calcareous sediments and organic matter. In the atmosphere, CO2 forms a weak carbonic acid with precipitation. After falling on land, the slightly acidified precipitation is neutralized by the weathering of silicate rocks, a process particularly active in warmer climates. These processes remove carbon from the atmosphere and transfer it to the world’s oceans as bicarbonate ions. The bicarbonate is removed from the oceans primarily by biological activity as calcium carbonate. The calcium carbonate settles to the bottom and enters the lithosphere.

Paleomagnetic data indicate that during the Cryogenian period, encompassing the Sturtian and Marinoan glaciations, most of the continental landmasses were located in the Earth’s warmer equatorial regions. This suggests that the rate of silicate weathering was high, lowering atmospheric CO2 concentrations, slowing greenhouse heating, and cooling the global climate. The global cooling lowered the silicate weathering rate, ultimately stabilizing the climate system at a new colder state.

Two additional phenomena are known to have occurred at the time, further contributing to high silicate weathering rates and lower CO2 concentrations. The first was the breakup of the pre-Pangean supercontinent named Rodinia which began approximately 830 million years ago and continued for nearly 200 million years. Silicate weathering rates are thought to be low when a supercontinent exists because most land area is far from the ocean and therefore very dry. When a supercontinent breaks up, formerly arid regions become wetter increasing weathering rates and reducing atmospheric CO2 concentrations.

The second phenomenon was the massive eruption of flood basalts around 723 million years ago in the present-day Canadian arctic which then lay close to the equator. Basalts weather rapidly and are a rich source of calcium ions. Model simulations published in the a February 2004 letter to the journal Naturetitled “A ‘snowball Earth’ climate triggered by continental break-up through changes in runoff” by Yannick Donnadieu, Yves Goddéris, Gilles Ramstein, Anne Nédélec, and Joseph Meert indicate that the combined effects of equatorial continents, supercontinent breakup, and low-latitude flood basalt emplacement are sufficient to cause a depression of atmospheric CO2 concentrations and trigger a global glaciation episode.

Survival of Life
An ice-covered Earth would curtail photosynthetic life on Earth and thus drastically deplete atmospheric oxygen. Detractors argue that this kind of glaciation would have made life extinct entirely. However, microfossils such as stromatolites and oncolites prove that, in shallow marine environments at least, life did not suffer any significant disruption. Proponents theorize that life could have survived or even flourished in the following locations:

• Deep oceanic hydrothermal vents.
• Under the ice in chemolithotrophic (mineral-metabolizing) ecosystems theoretically resembling those in existence under modern glaciers.
• Small regions of deep, open, ice-free ocean far from the supercontinent Rodinia, where photosynthesizers could have access to light and CO2.
• On high mountain areas in the tropics where daytime tropical sun or volcanic heat could create small temporary melt pools.
• In pockets of liquid water within and under the ice caps, similar to Lake Vostok in Antarctica.
• In small oases of liquid water near geothermal hotspots resembling Iceland today.

A continuing mystery is that the fossil record indicates that organisms and ecosystems do not appear to have undergone the significant change that would be expected by an extreme climate event or a potential mass extinction associated with the global glaciations. Even if life were to cling on in all the ecological refuges listed above, a whole-Earth glaciation should result in a biota with a noticeably different diversity and composition. This change in diversity and composition has not yet been observed in the fossil record — in fact, the organisms which should have been most susceptible to climatic variation emerge unscathed from the Snowball Earth.

Escape from Snowball Earth
Climate models, such as those developed by Dr. Budyko, suggest that once the Earth is covered in ice there would be no escape. Solar radiation, largely reflected by the glittering white surface, would be insufficient to loosen the icy grip. Yet, our currently ice-free tropics and temperate world indicate that the atmosphere warmed sufficiently to end the glacial event. Geological evidence indicates that elevated levels of CO2 concentrations in the atmosphere from volcanic outgassing led to rapid warming. Atmospheric concentrations of CO2 during a period of global glaciation would continue to increase because there were no open ocean surfaces to absorb the gas and no precipitation to remove it.

As advanced in the paper “CO2 levels required for deglaciation of a ‘near-snowball’ Earth,” by the authors Thomas J. Crowley, William T. Hyde, and W. Richard Peltier from the Department of Oceanography, Texas A&M University, published in the January 2001 Geophysical Research Letters of the American Geophysical Union, the CO2 levels necessary to unfreeze the Earth are estimated to have been about 130,000 parts per million, or 13% of the atmosphere. Their research indicates that, over 4 to 30 million years, enough CO2 and methane, mainly emitted by volcanoes, would accumulate to finally cause a strong enough greenhouse effect to lead to surface ice melting in the tropics. Eventually, an equatorial band of permanently ice-free land and water developed. Methane trapped in equatorial permafrost would be released adding to the greenhouse warming. The newly-exposed ocean and ground would be darker than the ice, and thus absorb more energy from the sun — initiating a “positive feedback” furthering the global meltdown.

On the continents, the melting glaciers would release massive amounts of water and glacial sediment flowing to the oceans. The resulting sediments supplied to the ocean would be rich in mineral nutrients which, combined with the abundance of CO2, would trigger a cyanobacteria population explosion, causing a relatively rapid re-oxygenation of the atmosphere. Researchers suggest that this vastly different oxygen-rich world was the setting for the rise of the Ediacaran biota and the subsequent Cambrian explosion. This positive feedback loop of mechanisms would free the Earth from ice in an astonishingly short period of time, perhaps less than 1,000 years. However, replenishment of atmospheric oxygen and depletion of the CO2 levels by ocean absorption and biological uptake would take further millennia.

Conclusion
Any theory that describes a radical departure from conventional models is sure to have critics. The Snowball Earth concept is no exception. The great antiquity of the Neoproterozoic glacial era deposits makes determinations relative to timing, global extent, and duration difficult and subject to uncertain interpretations in this developing area of study. Yet the geologic evidence for the occurrence of equatorial glaciations at this time is not disputed. However, the mechanisms, triggers, and processes that could lead to an ice-covered Earth continue to draw much debate. Does the Earth’s climate have a tendency to shift to a colder state? “Indeed, one of the great puzzles is why hasn’t this extent of global freezing happened since the Proterozoic,” said Jerry McManus, paleoclimatologist and professor of geological sciences at Columbia University’s Lamont-Doherty Earth Observatory in New York. Some scientists theorize a less severe Snowball Earth scenario that they term “Slushball Earth,” where the oceans were covered in a loose icy mush with large areas of open water rather than a rigid frozen surface.

But one thing is certain, faced with future Snowball Earth conditions, salt supplies at the hardware store would run out very quickly. “We’re gonna’ need a bigger snow shovel.”

Reasons to Join the Crowd -- Attend AAPG

Thirty five years ago I attended my first the AAPG Annual Convention and Exhibition in Houston. I interviewed with Texaco at that conference and within three months I began my professional career here in Houston. Since then I have attended all but two of the annual meetings. Why have I attended these meetings as well as several of the international conferences? There are several reasons for my continuous attendance at these conventions:

• The technical program provides a means to learn about some of the emerging exploration plays and new developments in the geosciences;
• There are numerous occasions for building and maintaining a professional network;
• Opportunities exist to present my work and have it vetted by peers.

This year, once again, the annual convention will be held in Houston and the Houston Geological Society will be acting as host. The technical program is quite robust and should provide those new to the industry an opportunity to begin building a strong technical foundation.

For those of us that have been around for a few years, there is the opportunity to see what is new and how things have changed. Just consider unconventional resources. A few years ago no one considered fine-grained rocks to be potentially exploitable reservoirs. They were considered source rocks and seals, but not reservoirs. Today, we view these rocks as complete petroleum systems. Concepts in geoscience are rapidly evolving and in a world of low natural gas prices we need to exploit these resources with a scalpel and not a machete. Our work requires a better understanding of where the core producing areas are and the stratigraphic position of the “sweet spot,” as well as the controls on both, and where the hydrocarbons are stored and ultimately how we can maximize production. These unconventional resources will be one of the eleven technical themes of this year’s convention. If the past is any guide to the future, this year’s meeting will also be an excellent networking opportunity. The last AAPG meeting in Houston was attended by more than 8100 attendees and this number may be exceeded this year. Use time between talks, during coffee breaks and lunch, at the many social events and in the exhibition hall to network. Meet new people working in your field and renew contacts face-to-face. We must all remember that a network is more than a connection on LinkedIn. An effective network requires nurturing, which means occasional face-to-face connections, phone calls, and emails. There is no better time for those face-to-face meetings than this year’s convention, and I will be scrambling to touch base with those in my personal network that has developed over the past few decades. A number of the contacts that I have made and nurtured at AAPG have over the years become friends and collaborators. They have provided data, technical reviews, and have helped with an interpretation of a unique dataset every once in a while.

I will also be presenting a paper at this year’s meeting. Early in my career, my reason for presenting at AAPG was to help establish my professional standing and to receive external feedback. I wanted to ensure that my thoughts, concepts, and beliefs were not too inwardly focused and limited by corporate needs and wants. Today, I believe that my professional standing has been established, but I still remain interested in having my work vetted. The program for this year has been set, but there will be opportunities to present at next year’s meeting in Denver or at the 100th Anniversary Convention in 2017 back here in Houston.

I strongly recommend that you register for this year’s convention. If you can’t break away from the office for the three days of the meeting, carefully review the program and pick a day to attend. All of us can find at least one day to attend this meeting. Professional conferences and conventions should truly be considered work and be part of one’s development.

There is more than AAPG for you to consider this month. The HGS Board has started considering awards and honors that will be presented this coming June. We have ideas but would like to hear from you. Are there members of the Society that you believe have contributed to the organization, the science, or the community? Send the Board a brief note letting us know who you believe should be recognized by the organization and why. At our January Board meeting, we decided to explore the idea of new awards so please don’t feel constrained by actions of prior boards. Remember, professional recognition is important.

Hoping to see you at the George R. Brown Convention Center in April.

Until next time...

Strategic Geology: The Mystery and Allure of Rare Earth Elements

Samarium, Praseodymium, Terbium, Lutetium. These sound odd. Are these break-away republics from the old Soviet Union? Maybe some new wonder drugs for weigh loss or baldness? In fact, these are members of a group of chemicals known as rare earth elements.

Samarium, Praseodymium, Terbium, Lutetium. These sound odd. Are these break-away republics from the old Soviet Union? Maybe some new wonder drugs for weigh loss or baldness? In fact, these are members of a group of chemicals known as rare earth elements.

The availability and supply of rare earth elements have become critical in the functioning of our modern high-tech economy. Concerned strategists may say the United States faces a crisis in the reliability of this supply due to a lack of domestic production and that the control of the majority of the world’s supply of rare earth elements by China puts the United States at risk of a supply disruption.

So, what are rare earth elements? How is their occurrence and abundance influenced by geology? And, why are they important?

Rare Earth Elements
Rare earth elements (REEs) are a group of seventeen metallic elements that occur together in the periodic table. The group consists of yttrium and the 15 lanthanide elements (lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium). Scandium is found in most REE deposits and is sometimes classified as a REE. The International Union of Pure and Applied Chemistry includes scandium in their definition of REEs.

These metals have many similar geochemical properties that often cause them to be found together in geological deposits. These metals are silver, silvery-white, or gray with a high luster and high electrical conductivity. Because these metals all bond strongly to oxygen, they tend to occur together in the structure of various minerals. These bonds also make them hard for refiners to separate.

The REEs are not as rare as their moniker would suggest. According to the United States Geological Survey (USGS) Scientific Investigations Report 2010-5220, titled the “Principal Rare Earth Element Deposits of the United States”, by the authors K. R. Long, B. S. Van Gosen, N. K. Foley, and D. Cordier, the estimated average concentration of the REEs in the Earth’s crust ranges from around 150 to 220 parts per million. These concentrations exceed that of many other metals that are industrially mined such as copper (55 parts per million) and zinc (70 parts per million). Unlike most commercially-mined base and precious metals, however, REEs are rarely concentrated into mineable ore.

The Geology of Rare Earth Elements
Economically important occurrences of REEs are associated with several varieties of uncommon alkaline igneous rocks including carbonatite, alkaline intrusive complexes, and peralkaline formations, as well as their weathering products. The United States has recently conducted studies of the occurrence and distribution of REEs. The USGS’s Mineral Resources Program’s Open-File Report 2011–1256, “Carbonatite and Alkaline Intrusion-Related Rare Earth Element Deposits – A Deposit Model” by Philip L. Verplanck and Bradley S. Van Gosen, presents the findings of some of this recent work.

As described in the USGS report, alkaline rocks form an expansive category of igneous rocks. Using a broad definition, alkaline rocks are deficient in SiO2 relative to Na2O, K2O, and CaO. Carbonatites are defined by the International Union of Geological Sciences (IUGS) system of igneous rock classification as having more than 50% primary carbonate minerals, such as calcite, dolomite, and ankerite, and less than 20% SiO2. Most identified carbonatites are intrusive bodies, but a few extrusive examples are known, most prominently an active carbonatite volcano in northern Tanzania. Peralkaline rocks are one subset of alkaline rocks, defined by (Na2O + K2O)/(Al2O3)>1.

Mineral deposits associated with carbonatites account for the greatest production of REEs. Important deposits are the Bayan Obo deposit in Inner Mongolia in China, and the Sulphide Queen carbonatite of the Mountain Pass district, California. Until the late 1980s, the Mountain Pass mine was the largest global producer of REEs, subsequently supplanted by the Bayan Obo deposit, which is currently the largest producer of REEs. Carbonatite REE deposits are extremely enriched in light REEs, particularly lanthanum, cerium, and neodymium. Although there are no peralkaline alkaline intrusion-related deposits currently being mined for REEs, many are in various stages of exploration because these igneous rocks contain relatively high concentrations of heavy REEs.

Carbonatites and peralkaline igneous rocks tend to occur within stable continental tectonic units, in areas defined as shields, cratons, and crystalline blocks; they are generally associated with intracontinental rift and fault systems. These igneous rocks formed from the cooling of silica-undersaturated, alkaline magmas, which were derived from repeated partial melting in the Earth’s upper mantle. The evolution of these initial mantle melts is not well understood. When these magmas ascend through the Earth’s crust, their chemical composition undergoes changes in response to variations in pressure, temperature, and composition of surrounding rocks. The result is an astonishing diversity of rock types that are variably enriched in economic elements such as zirconium, niobium, strontium, barium, lithium, and the REEs.

The principal REE-bearing minerals associated with carbonatites are fluocarbonates (bastnäsite, parasite, and synchysite), hydrated carbonates (ancylite), and phosphates (monazite and apatite). Other REE phases are less common, such as britholite and burbankite.

A common feature of most carbonatite and alkaline intrusion-related deposits is that the surrounding rocks have been hydrothermally altered because of alkali metasomatism. This style of alteration is known as fenitization, so-named because it was first described at the Fen alkaline complex in southern Norway. Alkali-rich fluids are released into the country rock from the crystallizing magma, and reactions convert the host rock minerals to an assemblage of alkali-bearing minerals. Fenites can be classified as sodium or potassium rich. Sodium-rich fenites are characterized by the presence of alkaline feldspar with alkali amphibole or sodic pyroxene, and potassium-rich fenites contain potassium feldspar.

Potentially useful concentrations of REEs can also be found in pegmatites and placer deposits. Among pegmatites, very coarse grained intrusive igneous rocks, the niobium-yttrium-fluorine family comprises a large number of subtypes formed in different geologic environments. These subtypes are granitic in composition and are usually found peripheral to large granitic intrusions. REE-bearing pegmatites have a limited extent and are of economic interest only to mineral collectors.

Placer deposits are sedimentary accumulations of the REE-bearing minerals, typically monazite and xenotime. Heavy minerals weathered from deeply eroded host rocks are preferentially sorted by hydraulic processes in fluvial or marine environments due to their higher densities. The source rock need not be an alkaline igneous rock. Many common igneous, metamorphic, and even older sedimentary rocks contain enough monazite to make the mineral ubiquitous in placer deposits. Placers types with the greatest concentrations of monazite are typically ilmenite-heavy mineral placers, which have been mined for titanium oxide pigments, and cassiterite placers, which are mined for tin.

Rare Earths in Texas
REEs have been extracted from at least three locations in Texas. These include the Williams mine in Llano County, the Cornudas Mountains in Hudspeth County, and the Caballo Mountains in Fisher County. Several tons of pegmatite ore were extracted from the Williams mine for the minerals prior to 1909. According to P. Möller in the 1989 paper, “Rare Earth Mineral Deposits and their Industrial Importance,” the REE-bearing minerals allanite, gadolinite, and fergusonite were mined along with fluorite from the Middle Proterozoic Town Mountain Granite.

In Hudspeth County, the REE-bearing minerals eudidymite and bastnäsite were extracted from the Victorio Peak Formation on the Diablo Plateau. A 1987 report, Alkaline Rocks and Carbonatites of the World, Part 1, by A.R. Woolley, published by the British Museum of Natural History, indicates that the ore was mined from the nepheline, syenite, and phonolite alkalic igneous host rocks. In the Caballo Mountains, Woolley reports that bastnäsite was mined from quartz monzonite and potassic dikes.

Expensive Extraction
The extraction of the metallic REEs from ores is difficult and costly. The ores are mineralogically and chemically complex and commonly radioactive. The already difficult metallurgical processes are compounded by the unique composition of each ore. No two are truly alike and there is no standard process for extracting and refining the ore into marketable materials. Before a new mine can be brought on line, extensive and costly testing is required using a variety of known and experimental extraction methods to optimize processing.

When elements of interest are found in two or more mineral phases within the same host material, each requiring a different extraction technology, the mineral processing is technically challenging. Current mineral-processing practices are capable of sequential separation of multiple mineral phases from one ore, but these methods are often not cost effective. Consequently, deposits where only one REE is concentrated will have a competitive cost advantage over deposits where multi-element extraction is conducted. To date, production has largely come from single-mineral-phase deposits, such as Bayan Obo (bastnäsite) in China, Mountain Pass (bastnäsite) in California, and heavy-mineral placers (monazite).

REE-bearing minerals, once separated, contain as many as 14 individual REEs that must be further separated and refined. The principal deleterious impurity is radioactive thorium. Because radioactive materials are difficult to mine and handle safely, they are heavily regulated. Radioactive mining tailings are often classified as hazardous waste requiring special and expensive disposal methods. The cost of handling and disposing of radioactive material is a serious impediment to the economic extraction of the more highly-radioactive REE-rich minerals. Monazite in particular typically contains considerable amounts of thorium.

Demand and Production
Before 1950, there was relatively little demand for REEs. At that time, most of the world’s supply was produced from placer deposits in India and Brazil and the Mountain Pass Mine in California was producing minor amounts of rare earth oxides from a Precambrian carbonatite. The demand for REEs began to accelerate in the mid-1960s as color televisions were beginning to be manufactured for the mass market. Europium was the essential material for producing the phosphors for the color images. Bastnäsite from the Mountain Pass Mine contained about 0.1% europium. By 1970, this demand made the Mountain Pass Mine the largest REE producer in the world and the United States the leading producer.

China began producing rare earth oxides in the early 1980s and became the world’s leading producer and exporter by the early 1990s. Through the 1990s and early 2000s, China steadily strengthened its share of the world’s rare earth oxide market. The Mountain Pass Mine, and many others throughout the world, were unable to compete with the low cost of production in China and stopped operation.

At the same time, world demand for rare earth metals was burgeoning with their use in materials for a wide variety of defense, aviation, industrial, and consumer electronics products. China capitalized on its dominant position, more than 90% of world production, by restricting exports in 2010 and allowing rare earth oxide prices to rise to historic levels. Due to these rising prices, mining companies in the United States, Australia, Canada and other countries began to reevaluate old REE prospects and explore for new ones. In 2012, the Mountain Pass Mine came back into production and the United States produced about 6% of the world’s REEs, with Australia making a little over 3%. Additionally, exploration and development projects have been initiated in Brazil, Finland, Greenland, India, Kyrgyzstan, Madagascar, Malawi, Mozambique, South Africa, Sweden, Tanzania, Turkey, and Vietnam.

Since 2010, prices have dropped sharply as the global economy slowed, new sources have come online, and companies developed methods to use less. Lanthanum oxide is currently around $6 per kilogram, far below its price of $104 in 2011, according to data provided by Australian rare-earth producer Lynas Corp and Mineralprices.com.

Uses
Although industrial demand for REEs is relatively small in tonnage terms, the materials are essential for a diverse and expanding array of industrial and high-technology applications. The primary uses are for chemical catalysts, metallurgy, and glass polishing. Increasing amounts of REEs are used in magnets, metal alloys for batteries and lightweight structures, and phosphors essential for many current and emerging alternative energy technologies, such as electric vehicles, energy-efficient lighting, and wind power. Several pounds of rare earth compounds are in batteries that power every electric and hybrid-electric vehicle. REEs also play an essential role in our national defense in their use in night-vision goggles, precision-guided weapons, communications equipment, GPS equipment, batteries and other defense electronics.

Strategic Implications
The global production and supply of REEs comes from only a few sources, with China foremost among them. The USGS Open-File Report 2011-1042, “China’s Rare-Earth Industry”, 2011, by P. Tse, points out that because of China’s earlier decisions to restrict exports, the United States and other developed nations have heightened concerns about future availability. In a December 13, 2013, Wall Street Journal article titled, “China Seeking to Trim Exports of Rare-Earth Minerals”, author Chuin-Wei Yap reported that China implemented a second round of export quota reductions of REEs despite a shrinking share of the global output. China’s Commerce Ministry said it would set its rare-earth export quotas for 2014 at 15,110 metric tons, a 2.5% decline from last year.

China’s announcement of lowered export quotas for REEs for 2014 was made despite a ruling against such export quotas by the World Trade Organization. Several recent legislative actions in the United States are aimed at mitigating the possible threat of REE supply disruptions. The National Defense Authorization Act authorizes the Pentagon to stockpile certain critical minerals, including dysprosium and yttrium. Using the National Defense Stockpile Transaction Fund, the Department of Defense may spend up to $41 million to acquire specified materials for each fiscal year from 2014 to 2019. In addition, the Defense Logistics Agency will encourage the domestic supply of strategic and critical minerals.

According to the Congressional Research Report, “Rare Earth Elements in National Defense” released in December 2013, United States policymakers have expressed growing concern that the nation has lost its domestic capacity to produce strategic and critical materials. The Critical Minerals Policy Act of 2013 included directives to develop methods for determining which minerals are critical resources, based on supply restrictions and demand, and to establish a comprehensive national assessment of critical minerals.

Meanwhile, a January 2014 article by Per Liljas in Time Magazine says that the British Islands-based private equity firm SRE Minerals Limited has announced that a geological study identified a deposit containing 216 million tons of REEs in North Korea. If verified, the discovery would more than double global known resources and be six times greater than the reserves in China. The report indicates that SRE Minerals Limited entered into a 25-year deal to develop the deposits in Jongju, northwest of the capital, Pyongyang. The USGS said there was insufficient information to comment on the significance of the announcement. SRE acknowledges the estimates are conceptual and not yet proven.

Summary
Maybe the REEs are not so much rare as undervalued. The geology and occurrence of the REEs is complex and the extraction technically challenging. When the invisible hand market finds the right price, multiple sources become available. So, it is not geology or engineering that makes REEs precious, but economics: supply and demand.

Some Musings from the President

My letters to the membership as Editor, and now as President, have focused on volunteerism, the need for continuous learning, and mentoring. When I sat down this month to prepare my letter I decided to take a different approach. I will share with you the top ten things that I have learned during my thirty-five year career. I hope they ring true to those of you that have been around a while and will be of some use to those that are just starting out. Not in any specific order these learnings are:

Energy – Water Nexus: Texas, Drought, Fracking, and Water

Energy and water resources are intricately intertwined in our modern economy. The production or use of one almost always requires the use of the other. Energy is used in water production to power pumps and associated equipment used to lift groundwater from beneath the earth, to desalinate brackish water, and to transport and treat potable supplies to users. Water is used to generate electricity at hydroelectric dams, to cool power generating stations, and during the extraction of fossil fuels. This interdependency is often called the Energy-Water Nexus.

The Energy-Water Nexus webpage of Sandia National Laboratories states: “These two critical resources are inextricably and reciprocally linked; the production of energy requires large volumes of water while the treatment and distribution of water is equally dependent upon readily available, low-cost energy. The nation’s ability to continue providing both clean, affordable energy and water is being seriously challenged by a number of emerging issues.”

Adequate affordable supplies of both clean water and energy are vital to our nation’s well being and prosperity. However, this co-dependancy can lead to conflict. In recent years, one of the most highly-visible areas of friction in the Energy-Water Nexus has been the use of fresh water in hydraulic fracturing activities. One can hardly open a newspaper without encountering a story about hydraulic fracturing and the affects of the growing use of the technology on clean water.

One of the locations where this conflict is ongoing is in south Texas where hydraulic fracturing activities are being conducted at an increasing pace to extract oil and gas from the Eagle Ford Shale.

Fracking and the Use of Fresh Water
Hydraulic fracturing, the practice of injecting water and a mixture of proppants and chemicals at very high pressure into a low-permeability, hydrocarbon-rich formation, has been used for decades to produce oil and gas. More recent developments in horizontal drilling technologies, combined with hydraulic fracturing, has led to a significant increase in the production of oil and gas from shale formations such as the Bakken in North Dakota, the Eagle Ford and Barnett in Texas, and the Marcellus in Pennsylvania and neighboring states.

Hydraulic fracturing operations involve the use of a large volume of fresh water. In general, one to six million gallons of water are used in the fracturing operations. at each well. The volume varies depending on the length of the target zone and the geomechanical properties of the producing formation. The majority of water used in fracturing operations is drawn from surface water sources. Secondarily, municipal water supplies and groundwater sources are used. Typically, the water is transported to the well site by tanker truck. A single fracturing job can require more than 300 tanker truck loads of fresh water.

Operators prefer to use fresh water for hydraulic fracturing because it is less corrosive than water with higher concentrations of dissolved solids. Lower quality water with higher concentrations of dissolved solids must be treated prior to use in fracturing operations. The additional costs associated with the treatment of low quality water makes the use of fresh water more attractive.

In many areas where hydraulic fracturing is conducted there are adequate supplies of fresh water available. In these areas, the use of the fresh water does not stress the existing available supplies are relied upon by other users. However, in drier regions where rainfall is rarer and surface water sources are allocated, the use of fresh water for fracturing can put stress on the local availability of water. Some of the drier areas where hydraulic fracturing is conducted are in Texas, specifically, in west Texas and south Texas.

South Texas and the Eagle Ford Shale
Average rainfall in parts of south Texas amounts to less than 20 inches per year. During many of the recent years, precipitation totals have fallen short of the annual average and the region is suffering through a persistent long-term drought. According to the United States Drought Monitor for the end of December 2013, more than 71 percent of Texas is in drought and large parts of south Texas are still in moderate or severe drought conditions despite recent rainfall. Under the rolling hills, scrub brush, and dusty ranch lands of south Texas lies the Eagle Ford Shale.

According to the Railroad Commission of Texas, the Eagle Ford Shale is a hydrocarbon producing formation of significant importance due to its capability of producing both gas and more oil than other traditional shale plays. The Eagle Ford contains a higher carbonate/shale percentage than similar shale formations, upwards to 70% in south Texas, which makes the formation more brittle and “fracable.” The Eagle Ford Shale play trends across 26 Texas counties from the Mexican border northeastward into East Texas, roughly 50 miles wide and 400 miles long with an average thickness of 250 feet. The formation is Cretaceous in age resting between the Austin Chalk and the Buda Lime at a depth of approximately 4,000 to 12,000 feet.

Petrohawk drilled the first well to produce oil and gas from the Eagle Ford Shale in 2008 in LaSalle County, Texas. In the first six months of 2013, the Eagle Ford produced 2.69 billion cubic feet of natural gas and 599,000 barrels of oil and condensate per day. This rate of oil production represents an increase of 51 percent over the average 2012 production rate. By the end of 2013, oil production from the Eagle Ford had increased to more than one million barrels per day. In 2011, the United States Energy Information Administration reported that the Eagle Ford had proven reserves of 1.25 billion barrels of oil and 8.4 trillion cubic feet of gas. More recent estimates of the oil reserves are in excess of three billion barrels.

Since Petrohawk’s initial well in 2008, drilling activity and associated hydraulic fracturing operations have been increasing rapidly in the Eagle Ford. These activities have required the use of fresh water in increasing quantities. But, the Eagle Ford underlies some of the most water stressed parts of the state. Following the severe drought in Texas in 2011, concerns have grown that use of fresh water for hydraulic fracturing in the area has been competing for this scarce resource with municipal, agricultural, and industrial users.

The Search for Fresh Water and Conflicts
Hydraulic fracturing of an average Eagle Ford well requires four to six million gallons of water, or roughly 15 acre-feet, over a period of several days, according to an industry source. An acre-foot, a measurement used in agriculture and municipal calculations, is the volume of water that will cover an acre of land to a depth of one foot. An acre-foot is approximately 326,000 gallons. Drillers working the Eagle Ford Shale in south Texas cumulatively use approximately 15,000 acre-feet (nearly 4.9 billion gallons) of water annually by some estimates.

A widely cited study from the University of Texas at Austin, funded by the oil and gas industry, had predicted that hydraulic fracturing in the Eagle Ford would use a maximum of around 35,000 acre-feet of water annually. The lead author, Jean-Philippe Nicot, a research scientist at Bureau of Economic Geology, said he now thinks the actual use in the Eagle Ford is around 40,000 acre-feet annually.

Operators point out that fracturing activities consume only about one percent of all fresh water used in Texas, much less than municipal and irrigation users. While the volume of water used is small compared to state-wide water use, the local affects can be magnified. The Southwest Research Institute, a non-profit, San Antonio-based research and development organization, estimated that the cumulative water use for hydraulic fracturing can be equal to approximately half the regional annual recharge in normal years to the Carrizo-Wilcox Aquifer, a major groundwater source for parts of the state.

This increasing consumption of fresh water for fracturing operations has caused concerns for some local water users in south Texas. Hugh Fitzsimmons, the owner of a large ranching property in Dimmit County 100 miles southwest of San Antonio and a board member of the Wintergarden Groundwater Conservation District is worried about use of the groundwater that often serves as the primary supply in the sparsely populated county. In 2009, there were just 107 oil and gas wells in Dimmit County. By 2012, there were 2,137. “It is not the process that I object to,” said Mr. Fitzsimmons in a September 2013 article in Time Magazine by Hilary Hylton, “but it’s all the ancillary issues that come with it. Air quality declines as some wells flare off gases, and heavyweight rigs and water-hauling trucks destroy back-country roads. But most of all, locals want the frackers to use less water.”

In a May 2013 column titled “Don’t mess with Texas water, frackers warned,” John Kemp a Reuters market analyst states that, “the real problem is not water supplies but their management.” He notes that the amounts of water employed in hydraulic fracturing are small relative to other uses, even in dry areas, and do not pose a serious threat to the availability of water. The potential for problems arises instead from the unusual system of water rights still employed in Texas and its relatively weak controls on groundwater use in some parts of the state.

Groundwater use in Texas is not regulated at the state level. Rather, state law allows the establishment of groundwater conservation districts which regulate groundwater use at the local or county level. In some counties, the groundwater conservation districts limit the pumping of groundwater. Some of these districts have exempted oil and gas operations from pumping limitations. Hydraulic fracturing has been granted exemptions from water-use restrictions along with traditional oil and gas drilling. But now some conservation districts are distinguishing fracturing operations from drilling and regulating the water use as a separate activity because fracturing uses up to 30 times as much water than simply drilling a well.

The Evergreen Underground Water Conservation District, encompassing all of Atascosa, Frio, Wilson, and Karnes counties, includes 2,461,000 acres or 3,845 square miles. The District’s economy is heavily dependent upon agriculture and agriculture related business. Approximately 80 percent of the total groundwater pumpage in the District is used in agriculture. The District, which overlies areas of Eagle Ford Shale production has implemented groundwater use restrictions for fracturing activities since 2008. The restriction limits the pumpage of fresh groundwater and brackish groundwater based on the acreage that the owner holds.

The scarcity and search for water sources in south Texas has led to a new revenue stream for some ranchers. According to a comment paper by Taelor A. Allen published in the St. Mary’s Law Journal in January 2013 titled “The South Texas Drought and the Future of Groundwater Use for Hydraulic Fracturing in the Eagle Ford Shale,” it has become common practice for many landowners to capitalize on the ability to sell water for hydraulic fracturing in a lucrative business known as ‘water wildcatting.’ Some landowners are receiving anywhere from ten to eighty cents per barrel of water.”

Another Water Source
A potential solution to conflict over the use of fresh water may be the use of another water source. This other water source might be the 2.7 billion acre-feet of brackish groundwater that lies beneath Texas. Brackish groundwater is currently going largely unused in Texas so its potential use would not conflict with any current users. Salts and chemicals in the brackish groundwater that are incompatible with the fracturing method can be removed by a variety of treatment methods including reverse osmosis. Halliburton, a major contractor in the hydraulic fracturing business, has a goal to reduce fresh water use by 25 percent in the United States by the end of 2014, according to industry reports. Reducing freshwater use “is no longer just an environmental issue — it has to be an issue of strategic importance,” Salvador Ayala, vice president of well production services told an industry group recently, according to the Wall Street Journal.

A Water Substitute?
Some operators are looking for ways to reduce the volume of fresh water used in hydraulic fracturing operations and are investigating the use of alternative fluids. In a June 2013 column on the financial website Motley Fool, David Smith writes that operators in Tennessee are experimenting with the use of nitrogen gas for shallow fracturing operations in the gas-bearing Chattanooga Shale. The nitrogen is used with water and additives to create a foam. The foam, which is 53 to 95 percent nitrogen, has the viscosity and related properties sought by the operator. The percentage of water used in the foam is often increased for deeper fracturing targets.

David Smith reports that, according to Air Products and Chemicals, a supplier of nitrogen, the use of the gas is about 15 percent more expensive than the use of fresh water. He notes however that the difference in cost is largely offset by an 11 percent increase in the estimated ultimate recovery of natural gas. An additional benefit of the nitrogen use is the elimination of costs associated with the collection, transport, and treatment of flowback water.

The potential use of nitrogen in fracturing operations is limited by several factors. Nitrogen use is most applicable in shallow operations, typically less than 5,000 feet deep. Also nitrogen is a poor carrier of proppant, so the target formation should be brittle with natural fractures that can stay open with proppant after the pressure is reduced.

The benefits of low-water volume fracturing in times of increasing water scarcity are hardly inconsequential. For instance, whereas in recent years farmers in some parts of Colorado paid from $9 to $100 for an acre foot of water to cities with excess supplies, energy companies are now paying $1,200 to $2,900 per acre foot.

Recycling Returns
About two-thirds of the water used in a hydraulic fracturing operation remains underground after drilling. The remaining third comes back to the surface as flowback. The flowback, which contains the fracturing additives plus residual materials from the formation and dissolved hydrocarbons, is a wastewater that is typically transported offsite for treatment and disposal. Proper management of the this waste stream involves significant costs. Often this wastewater is disposed underground through an injection well. Some states, including Colorado, require recycling of all flowback water recovered at the well site. Texas has added incentives to encourage drillers to recycle, but so far has not made this a requirement.

The oil and gas industry is moving towards greater development of recycling strategies and other injection options for the flowback water, according to David Burnett, director of technology at Texas A&M’s Global Petroleum Research Institute. Truck-mounted treatment and recycling units are now operating throughout south Texas. Researchers at the University of Texas at San Antonio are investigating charcoal as a potential water treatment option for the wastewater stream.

Summary
The interdependency and intricacies of the Energy-Water Nexus can lead to imbalances in the use and the availability of critical resources. The increasing application of hydraulic fracturing has led to great increases in the production of oil and gas from shale formations in many parts of the nation. This increase in the production of energy has led to greater prosperity for many, but has come at the cost of water availability for others. But the Energy-Water Nexus does not have to be a situation where one party wins and one party loses. As seen with the implementation of new strategies to reduce the use of fresh water resources in hydraulic fracturing operations, innovation and co-operative efforts can lead toward solutions that accommodate the needs and interests of all stakeholders.

A New Year's Resolution or Two

Let me begin by wishing Happy New Year to one and all! With the New Year we find ourselves making a series of resolutions and promises. As you assemble your list, I would like you to consider adding two items that I have included on mine, which relate back to themes that are often presented in my columns – volunteerism and continuous learning.

Fire and Ice: Gas Hydrates

In March 2013, the Japanese government announced that it had successfully produced methane from the icy gas hydrates within sediments underlying the Pacific Ocean. The effort, conducted from a drilling ship in the Nankai Trough about 100 miles east of Osaka, was the world’s first hydrate production test in deep water. Japan, the world’s largest importer of liquefied natural gas and a nation with few convention hydrocarbon reserves of its own, envisions a future powered in part by a constant supply of methane from the large undersea deposits of the “ice that burns.”

The program to study the deep sea gas hydrate deposits is led by the Japan Oil, Gas and Metals National Corporation (JOGMEC) and Japan’s National Institute of Advanced Industrial Science and Technology (AIST). The project is being conducted in collaboration with the United States Geological Survey (USGS) Gas Hydrates Project and researchers from the School of Civil and Environmental Engineering at Georgia Tech. This project is one component of an ongoing Japanese collaboration on methane hydrate research with the United States Department of Energy (DOE) and the Gulf of Mexico Gas Hydrate Joint Industry Project (JIP).

The research team accomplished the technically difficult goal of recovering cores from the gas hydrate deposits for laboratory testing. Well-preserved samples are extremely rare. They are preserved as “pressure cores,” with the gas hydrates kept as if they were still at the natural conditions in the subsurface where they formed. Gas hydrates are only stable at certain pressures and temperatures, and scientists have been working since the 1990s on sophisticated techniques to retrieve and preserve samples. The cores must be maintained under high pressures and low temperatures to prevent the hydrates from dissociating.

What are Gas Hydrates?
Gas hydrate, methane hydrate, or methane clathrate (CH 4•5.75H 2 O), is a naturally-occurring, solid form of methane gas combined with water molecules. The solid material is an ice-like substance formed when methane combines with water under specific pressure and temperature conditions. Gas hydrates can also be formed with other gases such as ethane, hydrogen sulfide, or carbon dioxide.

According the USGS Hydrates Primer (http://woodshole.er.usgs. gov/project-pages/hydrates/primer.html), at the molecular level, gas hydrate consists of gas molecules surrounded by cages of water molecules. Each water cage encloses a space of a particular size, and only a gas molecule small enough to fit within this site can be hosted in that specific hydrate structure. Clathrate hydrates are not chemical compounds, as the sequestered molecules are never bonded to the lattice. Structure I gas hydrate has 46 water molecules that enclose 8 sites where gas molecules may be hosted. Six larger gas sites are enclosed by water cages with 12 pentagonal and 2 hexagonal faces, while two smaller gas sites occur within pentagonal dodecahedral cavities. Without the support of the trapped molecules, the lattice structure of hydrate clathrates would collapse into conventional ice crystal structure or liquid water. Some researchers have likened the water cage structures to buckyballs.

Methane molecules can fit within both the small and large sites in the Structure I lattice, the most common type found in nature. Thus, “gas hydrate” and “methane hydrate” are often used interchangeably by researchers.

Methane hydrate takes many forms in sediments. In finegrained sediments, the methane hydrate can form in small pores and cement the grains, but may not be visible. Gas hydrate has also been recovered in chunks, in veins within sediments, and occasionally in large masses. According to the report “Energy Resource Potential of Methane Hydrate” dated February 2011 by the U.S. Department of Energy’s National Energy Technology Laboratory, methane hydrate is a fairly concentrated form of natural gas. When dissociated at standard temperature and pressure, one cubic foot of solid hydrates will yield about 164 cubic feet of methane gas.

Gas Hydrate Occurrence and Distribution
Gas hydrates are widespread and found in large volume in marine sediments at, and beneath, the ocean floor and in sediments within and beneath permafrost areas. These pressure-temperature conditions keep the gas hydrate “stable,” meaning the gases are contained in its solid form.

While gas hydrates can sometimes appear as clumps on the seafloor, researchers are most interested in the hydrates that form within sediments for potential energy production. Within the sediments, the source of the methane can be either microbial or from deeper thermogenic sources. The methane gas migrates upward until it mixes with water under specific conditions of temperature and pressure. Most of the gas hydrate occurs in the uppermost hundreds of feet of sediments at ocean water depths greater than approximately 1,500 feet and close to continental margins.

The spatial association of gas hydrates along continental margins is related to the availability of ample organic carbon from terrestrial sources or generated within the water column and incorporated into the sediments. Microbes use this carbon to generate methane. Microbial generation is the most common source for the methane observed in the studied natural gas hydrates. These observations may be biased by the relatively shallow sub-seafloor depths from which most of gas hydrate samples have been recovered.

Prior to 1995, there had been no dedicated drilling of gas hydratebearing deposits, and estimates of the amount of methane in the gas hydrates ranged widely. Conventional natural gas volumes are most often cited in units of trillions of cubic feet (TCF). Most studies published in the past 15 years have concluded that between 100,000 and 5,000,000 TCF of methane is trapped in global gas hydrate deposits. While the low-end estimate is more than 4000 times the amount of natural gas consumed annually in the United States, only a fraction of the methane sequestered in global gas hydrate deposits is likely to be concentrated enough and accessible enough to ever be considered a potential target for energy resource studies.

Potential Development
The sedimentary methane hydrate reservoir probably contains two to ten times the currently known reserves of conventional natural gas. This represents a potentially important future source of energy. However, in the majority of sites deposits are thought to be too dispersed for economic extraction. Other problems facing commercial exploitation are detection of viable reserves and development of the technology for extracting methane gas from the hydrate deposits.

Current studies on the potential development of gas hydrate resources are focusing on better understanding on several key factors likely to affect success. Besides investigating the porosity and permeability in various hydrate-bearing sediments, laboratory studies are performed on cores to measure the sediments’ thermal conductivity, that is, how quickly heat will flow through them. Additional areas of study are the mechanical properties like strength and stiffness of the sediment, both with hydrates and after the hydrates dissociate and the gas and water are removed.

The aim of the ongoing research is to develop innovative methods and gas recovery techniques, both for longer term tests and for eventual commercial production. For now, hydrate production calls for using conventional methods in which a well is drilled into sediments, lined with casing and kept filled with water. The water would be pumped out, lowering the pressure enough so the hydrates dissociate. Because water is produced along with the gas, the pumping would have to be continuous.

But the dissociation of hydrates is endothermic — it uses, rather than releases, energy — so when methane gas is produced, the sediments begin to cool. The cooling can slow or stop dissociation. To compensate for this production will probably have to involve the introduction of heat as well as pumping.

Conventional techniques would not work well in clays, which contain the vast majority of known hydrate reserves, because of the low permeabilities. In the research project headed by JOGMEC, where natural gas was extracted, specialized equipment was used to drill into and depressurize the hydrate deposits, causing the methane to separate from the ice. The gas was then collected and piped to surface.

In a September 2013 article in the New York Timesby Henry Fountain, Dr. Carlos Santamarina, a professor at Georgia Tech, said, “Much of the current paradigm for production in methane hydrates is anchored around oil production. And probably with that paradigm we may not go very far.” Despite the technical challenges, the potential for gas hydrates is huge.

Helium: The Other Natural Gas

Recently, I conducted an investigation of pore-space gases to evaluate potential migration of hydrocarbons through the soil. This investigation required the detection of potential equipment leaks. In these applications, helium is often used as a tracer gas because it is inert, non-flammable, and extremely rare in the atmosphere. Helium leaks can be readily detected with a hand-held instrument. The helium for this testing was drawn for a pressurized tank of a type that is widely available at retail. But if helium is so rare, where did the gas in this tank come from?

The Gas and Its Physical Properties
Helium is the second lightest and the second most abundant element in the observable universe where it makes up about 24% of the total elemental mass. This mass is more than 12 times greater than the mass of all the heavier elements combined. Most helium in the universe is helium-4 and is believed to have been created in the Big Bang and during the fusion reactions in stars.

Despite this abundance, helium, the lightest of the noble gases, is rare in the Earth’s atmosphere making up only approximately 0.00052% of the volume or 5.2 parts per million. In seawater, the concentration is only 4 parts per trillion. The atmospheric concentration is fairly constant despite the continuous release of helium from the lithosphere because most helium in the Earth’s atmosphere migrates upward and finally escapes into space. In the Earth’s heterosphere, the atmospheric zone more than 60 miles above the ground surface where gases separate by molecular weight, helium and other lighter elements are the most abundant gases.

At standard temperature and pressure, helium is a colorless, odorless, non-toxic, inert gas in the noble gas group. The boiling point of helium, -452° F (-269° C), is the lowest among the elements. This means that helium does not become a liquid until just a few degrees above absolute zero. A chemist or a physicist will tell you that the “nuclear binding energy” of helium-4 is very high which is why it is a product of both nuclear fusion and radioactive decay.
 

Helium, named for the Greek god Helios, was first detected in 1868 by the French astronomer Jules Janssen and the British physicist Norman Lockyer in the spectra from a solar eclipse. In 1895, helium was formally discovered on Earth by the Swedish chemists, Per Teodor Cleve and Nils Abraham Langlet. The Swedes observed the gas emanating from the uranium ore cleveite.

Geological Origin
Most terrestrial helium was created by the natural decay of heavy radioactive elements, principally thorium and uranium, in the minerals cleveite, pitchblend (uraninite), carnotite, and monzanite. These minerals are often found in granitoid basement rocks. The decay of these elements emits alpha particles which consist of two neutrons and two protons. Alpha particles are the same as helium nuclei. The nuclei pick up electrons from the surrounding rock. These processes are estimated to generate approximately 3,300 tons of helium per year in the Earth’s crust where the concentrations are up to eight parts per billion.

Because helium migrates and is trapped in the subsurface under conditions that also trap hydrocarbons, the greatest natural concentrations of helium on the planet are found in natural gas. Most unprocessed natural gas contains at least trace amounts of helium, yet very few natural gas fields contain commercially exploitable concentrations. Helium concentrations in natural gas vary over a wide range from a few parts per million to greater than 70,000 parts per million (7 percent). Natural gas must contain at least 0.3% helium to be considered as a potential helium resource.

The wide range of helium concentrations in natural gas is determined by the geological setting. The geological setting most favorable for the accumulation of higher concentrations of helium involves the juxtaposition of three conditions:

1) Granitoid basement rocks rich in uranium and thorium at a relatively shallow depth;
2) Fractured and faulted basement rocks providing a pathway for the helium to escape; and
3) An overlying trap consisting of a porous reservoir of sedimentary rocks capped by an impermeable seal.

The nature of the seal is critical for the accumulation of helium gas in exploitable concentrations. Helium has the smallest atomic radius of any element, about 0.2 nanometers. As it migrates upward through the stratigraphic column, the gas can fit through very small pore spaces. Typically, halite or anhydrite are the only sedimentary rocks that can block the upward migration of helium atoms. In some cases, shales with pore spaces plugged with abundant organic materials (kerogen) can serve as a less effective barrier.

By 1903, large reserves of helium were identified in natural gas fields in Oklahoma, Texas, and New Mexico. The Hugoton (Kansas, Oklahoma, and Texas), Panhandle West, Panoma, Riley Ridge in Wyoming, and Cliffside Fields are the gas fields where most domestically-produced helium has been extracted in the last 75 years.

The natural gas fields in northwest New Mexico have some of the highest known helium concentrations. These elevated levels of helium in natural gases occur in Paleozoic reservoirs on the Four Corners Platform and also in Paleozoic reservoirs in the deeper parts of the San Juan Basin. According to a 2012 publication by R.F. Broadent titled Helium in New Mexico: Origins, Uses, Economics, Geologic Distribution and Exploration Possibilities, the regional set of orthogonal faults that offset Precambrian basement throughout the deeper parts of the San Juan Basin may have acted as migration pathways that transmitted helium from its basement source into overlying Paleozoic reservoirs.

Helium Production and Storage
Helium is commercially extracted from natural gas by a low temperature separation process called fractional distillation. Since helium has a lower boiling point than any other element, low temperature and high pressure are used to liquefy and draw off nearly all the other gases (mostly nitrogen and methane). The resulting crude helium gas (50 to 70 percent helium) is purified by successive exposures to lowering temperatures, in which almost all of the remaining nitrogen and other gases are precipi tated out of the gaseous mixture. Activated charcoal is used as a final purification step, usually resulting in 99.995% pure Grade-A helium. The principal impurity in Grade-A helium is neon. In a final production step, most of the helium that is produced is liquefied via a cryogenic process. This is necessary for applications requiring liquid helium and also allows helium suppliers to reduce the cost of long distance transportation.

The United States began stockpiling helium after World War I because Congress was concerned about catching up with the Germans in the race to build a fleet of dirigibles. In 1925, the United States established the National Helium Reserve, also known as the Cliffside Field Government Reserve, near Amarillo, Texas to serve as a strategic supply of helium for use in airships and other defense purposes.

The Bureau of Mines constructed and operated the large helium extraction and storage facility that went into operation in 1929. From 1929 to 1960 the federal government was the only domestic producer of helium. Although the use of airships declined after World War II, new defense uses for helium arose such as a purging gas when refueling rocket engines and as a coolant in nuclear weapons programs.

As of December 2006, the total helium reserves and resources of the United States were estimated to be 744 billion cubic feet (BCF). This included 153.2 BCF of measured reserves, 192.2 BCF of probable resources, 213.8 BCF of possible resources, and 184.4 BCF of speculative resources. Included in the measured reserves were 24.2 BCF of helium stored in the National Helium Reserve. Helium resources outside of the United States are estimated to be approximately 1.13 trillion cubic feet. The majority of these resources are located in Qatar (362 BCF), Algeria (294 BCF), Russia (244 BCF), Canada (72 BCF), and China (40 BCF).

The National Helium Reserve is now operated by the Bureau of Land Management (BLM), a branch of the Department of the Interior, under the Federal Helium Program (Public Law 104-273). The Federal Helium Program includes all operations of the Bush Dome and Cliffside Field storage reservoirs in Potter County, Texas and the crude helium pipeline system. The BLM no longer supplies Federal agencies with Grade-A helium. Private firms that sell Grade-A helium to Federal agencies are required to purchase a like amount of (in-kind) crude helium from the BLM.

Usage and Price
Due to its properties, helium plays a unique role in many commercial applications. Helium is used extensively in cryogenic applications, particularly in the cooling of superconducting magnets. The main commercial application for superconducting magnets is in medical equipment, particularly in magnetic resonance imaging scanners. There is no substitute for helium in cryogenic applications if temperatures below –429 °F are required. Cryogenic uses consume approximately one quarter of the United States production. Helium’s other industrial uses, accounting for approximately 50 percent of production, include: a pressurizing and purge gas, protective atmosphere for arc welding, and in processes such as growing crystals to make silicon wafers. The most well-known use is as a lifting gas in balloons and airships.

In 1995, Congress decided that the National Helium Reserve was not essential and initiated a program to sell the stored helium as part of the Helium Privatization Act of 1996 (Public Law 104–273). In accordance with the Act, the BLM began selling off the gas to private companies, while keeping 600 million cubic feet in reserve. The liquidation of the reserve had the aim of reducing the debt incurred by the program, but the sales also artificially depressed the price of helium.

Since then, up to one half of the world’s helium demand has been met through sales from the reserve and, in some years, more helium was exported out of the United States for use overseas than was consumed domestically. Many analysts believe that the dumping of National Helium Reserve supplies onto the market has depressed the price of helium so much that it is being used as a cheap substitute for argon and other gases that have a much less limited supply, and thus is being wasted.

According to the January 2013 United States Geological Survey Mineral Commodity Summary estimated domestic consumption of helium gas in 2012 was 1.8 BCF. The price for crude helium in fiscal year 2012 was $65.50 per thousand cubic feet to government users and $75.75 per thousand cubic feet to nongovernment users. The price for the government-owned helium is mandated by the Helium Privatization Act. At the same time, the estimated price Grade-A gaseous helium from private industry sources was about $170 per thousand cubic feet. Many argued that the government was not getting a fair price for the helium.

Amid the rising concern related to the closing of the Federal Helium Reserve, the House of Representatives passed bipartisan legislation on September 26, 2013 to postpone the government mandated shutdown in October 2013. President Obama signed the Responsible Helium Administration and Stewardship Act of 2013 into law which prevented the premature closing of the reserve.

The Future
Although helium is continually being produced by radioactive mineral decay in Earth’s crust, the rate of natural production and accumulation is so low that the gas can be considered a nonrenewable resource. Some analysts estimate that, based on the forecasted rated of consumption and the volume of the known reserves, the helium supply will be depleted in about 40 years.

The commercial development of helium production has been stymied by the government-mandated price during the liquidation of the reserve. Industrial consumers are concerned that the market will be undersupplied when National Helium Reserve sales are discontinued. When that occurs, free market forces could lift the price of helium by an order of magnitude as commercial capacity will be inadequate to meet demand. As the helium marketplace shifts from one dominated by distributions from the government reserve to a true commodity, the price will surely rise.

Producing helium is capital and energy intensive. Energy costs strongly affect the cost to refine helium from natural gas. A large investment is needed in facilities, storage, and pipelines for commercial scale helium production. With the market price of helium in flux, commercial interests are reluctant to make the required investments. But with forecasts for rising prices and potential shortages, new helium production plants are being built outside the United States.

Domestic suppliers are making plans to construct facilities to meet the future demand of industrial users. Geologists will play an important role in identifying geological settings favorable for the generation and accumulation of commercial concentrations of helium in natural gas reservoirs. So, while the exploration for natural gas will continue to draw most of the attention of a large number of geologists, some of them will be on the lookout for helium, “the other natural gas.”
 

Change is Needed, are We Ready?

The world changes and organizations need to evolve or face extinction. Ultimately, organizations disappear due to the lack of interest and an inability of their reduced membership to support their overhead and infrastructure. This could be the fate of HGS, if we do not consider current and future trends and accept the fact that the conditions have changed over the past few years. Change is not easy, especially for those who have been heavily involved in running the organization. But change is necessary for future success.

A Little of Your Time, Please

Professional societies, such as the HGS, rely on volunteers to manage and carry out much of the organization’s programs. These individuals truly represent the life blood of the society. Without the different committee members’ active participation, the various monthly technical meetings, training opportunities, and social/networking events would not occur. Of the more than 4000 members of HGS only a relatively few, probably about 100, are actively engaged. Thus, the majority of our membership has become dependent on a relatively small number of active members. Currently this model appears to be working, but one needs to look “under the hood” to see how long this can continue without new people joining the volunteer pool. When examining the “engine” we see a number of issues that may become problems down the road.

 

1. The HGS is suffering from the same demographic issues as the oil and gas industry, and the key “boomer” generation is beginning to retire in large numbers. There is a significant gap in the number of mid-career individuals, representing the general lack of hiring during the downturn of the 90s. Historically, geologists become most active in professional societies during their mid-career. The newer employees are spending much of their time learning the needed skills and, in some cases, growing their families.

2. Employer demands on time have increased, driven by the continuous demand for increased productivity in the “office.” Individuals are now tethered back to the office with their smartphone and laptop. For many it appears that there is an expectation of being on call 24/7. With such office demands, free time has become quite valuable and is often spent with friends and families rather than being involved with professional organizations. The drive toward increased productivity in the office has also in many cases resulted in companies no longer encouraging their employees to become involved, and occasionally even discouraging such activities.

3. The demand for HGS volunteers is increasing. In addition to the routine work of the Society, HGS will be hosting several major meetings over the next few years and providing volunteers for two AAPG meetings, including the 100th anniversary of ACE, and a GCAGS conference. Each of these events requires a significant demand on the limited volunteer pool which can result in the onset of volunteer burnout.

So yes, things are continuing to run, but the question remains: how long can we expect things to continue before the signs of wear and tear begin to show, unless there are some changes? I don’t have a simple answer as to when this will occur, just as I can’t tell you when peak oil will occur. However, similar to the extension of peak oil that has resulted from changes in technology, there are actions that can maintain the viability of HGS long into the future. The first action is to increase the volunteer pool. Members who have not been active now need to come forward and join a committee or stand for an office. The addition of 1 to 2% of our membership to the volunteer pool would relieve much of the stress and delay the anticipated burnout. Many of the HGS events have been handled by the same small groups for multiple years and the volunteers concerned deserve relief.

There are other actions that would involve structural changes as to how HGS functions and what it delivers. Some of these changes are currently being made by the HGS Board. We are reviewing the current committee structure and determining which committees and functions can be eliminated or merged. These changes would have only a minimal impact on the vast majority of the membership. Examples of two of these changes were the elimination of a printed membership directory and the elimination of the annual holiday party in its present form. The Board determined that in a digital world a static directory was no longer viable. It was understood that some members would still want a hard copy, so provisions are being made to publish the HGS directory on demand. This would shift the responsibility from a volunteer to the permanent office staff and provide a more up to date membership listing. The decision to cancel the holiday party was made after reviewing attendance and the cost to the society over the past several years. A very small portion of the membership, about 1.5% (60 people total including members and guests) generally attend. Alternate options are being considered.

Another proposed change will require amendment(s) to our bylaws. The HGS Board will be proposing to the membership changes in the manner which candidates are nominated for board positions. Instead of requiring the ballot to have two or more candidates for all positions, except for the editor-elect, positions on the ballot could be represented by a single candidate selected by the nominating committee. The proposal does not mandate a single candidate or a slate. We chose this path although a number of professional and other non-profit organizations present a slate to their membership for endorsement. The proposal provides both flexibility and a means to carry-out an election when more than one candidate cannot be secured without a significant amount of arm twisting. Historically, those that were not originally interested in serving tend to be members of the Board in name only and do not effectively serve the membership. This proposed approach toward increasing flexibility in the HGS election process is not without controversy. Some oppose such an amendment, citing a loss of democracy and a fear that this could lead to appointed boards. As a result of these concerns, we will provide time for discussion before the proposal is formally put before the membership. This discussion will take place on the HGS website, where open comments can be posted. We believe that this proposal will provide for a strong leadership team to be in-place for years to come. This will permit the organization to thrive and will also ensure that those that are interested in serving will have an opportunity to do so. More on this will be forthcoming. Please review this material and when the time comes — vote!

One last quick note: if you haven’t yet registered for the Applied Geoscience Conference “Interdisciplinary Micro to Macroscale Geomechanics” taking place November 4-5, please consider doing so. The program looks outstanding.

Until next month…
 

Forensic Geology: Paper Balloons and Sand

The bit chatters and the cuttings come over the shaker covered in sticky brown drilling mud. After washing off the mud, the bits of Pliestocene alluvium from 900 feet below North Hollywood in California’s San Fernando Valley glisten in a multitude of colors and shapes. The angular rock fragments were sourced from the exposed hard rock formations in the surrounding San Bernardino, Santa Susana, Verdugo, and San Gabriel Mountains. These source rocks include the grantoid Palm Canyon Complex, the Mendenhall Gneiss, and the Lowe Granodiorite. This unique assemblage of rock fragments is characteristic of this location and only this location. Expert analysis of this handful of alluvium would be able identify the the exact location of its origin.

Building a Legacy

It has been an interesting past few weeks. As interest rates have turned slightly upward, a number of my long-time colleagues have begun to pre-announce their retirement plans. The demographic cliff that human resources staffers and management have been talking about is no longer over the horizon but is within clear sight. Discussions at various leadership meetings have taken on a new character. Within industry, the questions at these meetings now focus on whether the succession and training plans were sufficient to deal with “the great crew change.” Within professional organizations and societies the questions focus on how to maintain and grow their relevance to the “young professional."

 

America's First Paleontologist: Thomas Jefferson and Megalonyx

Thomas Jefferson, founding father and author of the Declaration of Independence, was a keen observer of the natural world and was greatly interested in the developing fields of geology, mineralogy, and vertebrate paleontology. This interest led to his encounter with the mysterious creature that he called Megalonyx, "a carnivorous clawed animal entirely unknown to science."

"In the present interior of our continent there is surely space and range enough for elephants and lions, if in that climate they could subsist; and for the mammoth and megalonyxes who may subsist there. Our entire ignorance of the immense country to the West and North-West, and of its contents, does not authorise us so say what is does not contain."

Big Bone Lick, located in Boone County, northern Kentucky, was one of the most famous paleontological sites in North America. Throughout the mid 1700s, vast quantities of "elephant" bones were collected from this area and transported to museums throughout the world. In 1807, Captain William Clark was commissioned by President Jefferson at his own expense to excavate bones from Big Bone Lick for scientific study. This made Big Bone Lick the first official paleontological collecting site in North America. Jefferson later unpacked, sorted, and studied a shipment of the fossils from Big Bone Lick in the East Room of the White House.

In his 1951 article Thomas Jefferson and the Geological Sciences, Joel Martin Halpern, Professor of Anthropology at the University of Massachusetts, noted that Jefferson, like scientific thinkers before him, puzzled with the problem of marine fossils in the rocks on mountain tops. While studying fossil shells found in the Andes of South America at an elevation of 15,000 feet above sea level, Jefferson was not willing to accept this as evidence of a global, biblical deluge. Jefferson observed that there was no source of water that could cover the Earth to a depth of 15,000 feet. He calculated that converting the entire atmosphere to liquid would cover the globe only to a depth of 35 feet. Jefferson concluded that the deluge hypothesis was "unsatisfactory and we must be content to acknowledge that this great phenomenon is yet unsolved."

A fine mathematician and astronomer, Jefferson could reckon latitude and longitude as well as a ship captain. He calculated the eclipse of 1778 with great accuracy and was able to make suggestions for the improvement of almanacs on the calculation of time. Jefferson was considered expert in anatomy, civil engineering, physics, mechanics, meteorology, architecture, and botany. He was able to read and write Greek, Latin, French, Spanish and Italian. While addressing guests attending the April 29, 1962 dinner honoring the Nobel Prize winners of the Western Hemisphere, President John F. Kennedy remarked: "I want to tell you how welcome you are to the White House. I think this is the most extraordinary collection of talent, of human knowledge, that has ever been gathered together at the White House, with the possible exception of when Thomas Jefferson dined alone."

Because of his wide range of knowledge and skilled power of observation, Jefferson was ahead of many contemporary scientists along several lines of inquiry. Even so, Jefferson never failed to acknowledge that in science he was "an amateur." Thomas Jefferson was many things: statesman, revolutionary, author, university founder, politician, surveyor, and agronomist. But was he a geologist?

Jefferson was wrong about Megalonyx. The fossils were not the remains of an enormous American lion as he postulated. In 1799, Caspar Wistar, Philadelphia physician, anatomist, and president of the American Philosophical Society succeeding Jefferson, correctly identified the remains as belonging to a giant ground sloth. In 1822, Dr. Wistar proposed naming the species Megalonyx jeffersoniiin honor of the former president.

Jefferson’s view of the history of life on Earth was burdened by centuries of religious belief and entrenched dogma. He had no formal training in earth sciences and he had few contemporaries to collaborate with and explore new concepts. In the December 6, 1935 issue of Science, noted geologist and Columbia University professor Henry Fairfield Osborn wrote, “Jefferson was a pioneer in the natural sciences and specifically in paleontology.” So, even though he erred in his analysis of the Megalonyxfossils, Jefferson earned his place as a founding father of geology in the United States.