Charles Henry Hitchcock

Member of initial Council and Active Founder (sources: Upham, 1919; Fairchild, 1932).

Personal. Charles Henry Hitchcock was born in Amherst, Massachusetts, on August 23, 1836, and died in Honolulu, Hawaii, on November 5, 1919.  He was the sixth child of Edward Hitchcock, then Professor of Chemistry and Natural History at Amherst College, and Orra White, a woman with a classical education and scientific and artistic talent. He graduated from Williston Seminary in 1852, and from Amherst College in 1856. He received his M.A. degree from Amherst in 1859. Originally, Hitchcock had intended to pursue theological studies, as his father had once done, and to become a pastor. After Amherst, however, he became an assistant in his father’s geological work as State Geologist of Vermont. This led Charles Hitchcock to choose geological studies as his life’s work. During 1861-1862, he was State Geologist of Maine. Later, he received perhaps his most important appointments, as State Geologist of New Hampshire (1868 to 1878) and as Professor of Geology and Mineralogy at Dartmouth College (1868 to 1908). After 40 years at Dartmouth, Hitchcock moved to Honolulu, where he had previously made several visits, and where he spent his last 11 years studying volcanic phenomena. Hitchcock married Martha Bliss Barrows, a professor’s daughter, in June 1862. They had two sons and three daughters. Martha died in February 1892 and, in September 1894, Hitchcock married her sister, Charlotte, who then survived him.

Professional. Charles H. Hitchcock is best remembered for his pioneering geological survey of northern New England, especially his work in New Hampshire. He also made important contributions to the burgeoning knowledge of glacial geology in this area, including his recognition of glacially transported boulders on the summit of Mount Washington, with their implications for the former extent of the ice sheet that once completely buried the mountain. He compiled a geologic map of the United States in 1872 (with W.P. Blake), and in 1881 issued a larger scale version for use in schools. His final work stemmed from his residence in Hawaii and involved study of its volcanism.

Role as a Founder. C.H. Hitchcock was one of the most active leaders in the founding of the Geological Society of America. In 1881 he was appointed Secretary of the committee that was formed at the American Association for the Advancement of Science (AAAS) Cincinnati meeting to consider the advisability of establishing a geological society independent of the AAAS. During 1883 and 1884, as Vice-President of AAAS and Chairman of Section E (Geology and Geography), he favored independence. In the June 1888 issue of American Geologist, Hitchcock, with N.H. Winchell, renewed the 1881 initiative by publishing a call for all geologists to assemble on August 14 at the Cleveland meeting of AAAS for the purpose of organizing an American geological society. At that meeting, Hitchcock was a member of the committee charged with drafting a constitution for the new society. He was on the first Council (1889 to 1892) was Second Vice-President (1895), and First Vice-President (1896). Ironically, despite all his efforts on behalf of the new society, C.H. Hitchcock never was elected to serve as President of GSA.

From April 14-19, 2013, in Galveston, Texas, 80 professionals from 11 countries gathered for an event for the record books. This week marked the first-ever Joint Penrose/Chapman Conference, titled “Coastal Processes and Environments Under Sea-Level Rise and Changing Climate: Science to Inform Management.” A very clear set of objectives were set for the group: (1) To provide a forum for discussing the latest advances in coastal systems response to both natural and anthropogenic influences; (2) To generate a consensus statement from this esteemed, international body of scientists that coastal change is occurring now and in many areas at an alarming pace; and (3) to assure that the outcome of this meeting is conveyed to the general public and to policy makers.

Did we accomplish these goals? Well… let’s start from the beginning.

One of the many reasons science needs to inform management in the coastal zone. Although the house currently is not occupied, it was still constructed in front of the dune line. Photo taken at Surfside Beach, the first field trip stop.

My name is Laura Guertin, and I’m an Associate Professor of Earth Science at Penn State Brandywine in Media, PA. My Ph.D. is in marine geology and geophysics from the University of Miami’s Rosenstiel School of Marine and Atmospheric Science. My dissertation research involved creating an integrated chronostratigraphy and sea-level history of the Late Cenozoic mixed carbonate-siliciclastic sediments of the south Florida platform from a series of continues cores drilled in the Florida Keys and Everglades National Park. My recent research has gone on more of a pedagogical tangent, but after I saw the title of this Penrose/Chapman Conference, I knew I had information I could contribute, and even more information I could learn.

The conference agenda included 51 talks, 29 posters, 1 panel discussion, and 1 field trip, across a range of categories. Talks focused on the record of sea-level rise, examined case studies of the coastal response to sediment supply, explored coastal evolution in carbonate environments, and integrated field results and modeling. The talks were filled with approaches, risks, and scenarios for exploration. For example, since 1930, there has been a 10-inch rise in south Florida sea level. And with a projected 16-inch sea-level rise in northern California, the runways at San Francisco airport will be submerged. Besides these sound bites, there were some powerful closing statements to talks, such as the talk that examined sand transport dynamics in the lower Mississippi River and an exploration of sustaining the landscape. The speaker concluded that, “unless society is willing to abandon deltaic landscapes, engineering diversions that disperse sediment to build land are necessary to counter future land loss.” For some people, this statement may seem straightforward, but when you put the supporting data and images behind this statement, then the statement becomes a powerful message that can be shared with scientists and non-scientists alike, and perhaps trigger a call to action.

Although there were several presentations focusing on the Gulf of Mexico coastline, several international locations were presented as case studies for challenges and successes in coastal management. For example, the Philippines, coastal erosion is prevalent and severe in many places, but it is not yet recognized as a national issue. There is only one geologist in the Philippines working on coastal erosion! In the Dutch coastal system, they are able to successfully secure sand from the North Sea, which has large volume of sand available, to build a sand buffer for coastal renourishment. And in the Ganges-Brahmaptura tidal delta, flooding is not necessarily a “bad thing,” as communities in this region have figured out how to cope and exist with periods of flooding and non-flooding.

The field trip took the group along the coast from the former Brazos River Delta to the east end of Galveston Island and focused on the Holocene evolution of the coast and current changes that are due to acceleration of sea-level rise, limited sediment supply and human influence. Evidence from flooding, channel construction, and even modern-day dune migration was visible along the way. One of the exciting parts of the field trip for me was to finally visit and be able to stand on top of the Galveston Seawall, a structure I teach about in my Natural Disasters course when discussing the 1900 Galveston Hurricane.

Could strong winds cause difficulty for instruction and information sharing at field trip stops?                     It was nothing a little duct tape and the side of a bus couldn’t fix!

Sign partially buried by dune at San Luis Pass.

While I was in Galveston for the week, I was blogging daily for my students back at Penn State Brandywine (http://journeysofdrg.org). I teach introductory-level Earth science courses for non-science majors, so I kept my postings at a more basic science level (leaving out the terms “paraglacial” and “ecomorphodynamic,” for example), but always including some take-home messages from each day.

This phrase was one of my points from the first day of the conference: At the end of the day, the group agreed there are components of sea-level rise we have consensus on, and some parts that we do not. We still have a lot of work to do, and we need to continue to communicate as clearly as possible what we do know.

This phrase was from my post on the last day of the conference: In the end, we all agreed that we need to emphasize to policy makers that decisions have to be made with existing uncertainty. We also agreed that we as scientists need to get involved with policy by serving on boards/committees and communicate more with the public.

I’m sensing a theme here….

So, if I go back to the beginning of this post, where I ask if we accomplished the objectives set by the conveners, where do we stand? The conference was certainly successful in allowing scientists to communicate the observed and modeled complexities within local-to-global coastal environments. We as scientists are now informed, energized, and ready to move forward even more than we already are with our communications to policy makers and the general public. Be sure to keep an eye out for the conference “consensus” statement developed by the conference participants in future issues of GSA Today and EOS. And with the challenges and complexities in coastal environments, I am sure this is not the last time you will hear from this group.

Hats off to the conveners of this first-ever Joint Penrose/Chapman Conference! The hard work and efforts of these trailblazers were essential in gathering such a dynamic group for an important discussion on the dynamics of our coastal zone: John Anderson (Rice University); Margaret Davidson (NOAA); John Geissman (Univ. of Texas at Dallas); Gary Hampson (Imperial College, London); Denise Reed (The Water Institute of the Gulf); Torbjörn Törnqvist (Tulane University).

The Galveston Seawall. Note the line of boulders in front of the seawall to dissipate the wave energy before the water washes up the curved surface of the wall.

Two of my favorite topics of geoconversation are how new subduction zones get started and when in Earth’s history did plate tectonics begin? Both are fascinating geoscientific questions but we seem to be making more progress on the first topic than on the second. The plate tectonic revolution changed our science forever but in the excitement of the late 1960’s when the paradigm shifted, the question of what makes the plates move was neglected. Yes it was mantle convection, but was convection driven by hot deep mantle rising or cold dense lithosphere sinking? Geodynamicists soon began investigating and now they tell us that it is mostly the sinking of dense lithosphere in subduction zones, pulling the plates and moving them. The most important consideration is that hotter asthenospheric mantle is slightly (~1%) less dense than colder overlying lithospheric mantle, so these want to change places. This sometimes happens during detachment and delamination of lithospheric mantle but generally happens by subduction, the end-on sinking of lithosphere beneath asthenosphere.

Our modern understanding of what drives the plates shows us that the key to understanding how subduction zones form is by understanding the density and strength of oceanic lithosphere. It also tells us that we should be thinking about lithospheric strength and density when we try to answer the question “When did plate tectonics start on Earth?” Certainly the Archean mantle 2.5 to 3.8 Ga was hotter than is the modern mantle. Consequently, Archean lithosphere would have thinner and more buoyant, and on this basis alone a reasonable person would conclude that plate tectonics must have been more difficult back then. In spite of this, most geoscientists think that plate tectonics was underway in Archean time. Regardless of your opinion on this matter, the question of when did plate tectonics start (WDPTS?) is one of the most important – and exciting – unresolved questions in the history of the solid Earth. I find this to be a particularly interesting question because EVERYONE can get involved: graduate students, undergraduate students, K-12 students, professors, amateurs, the media. We can’t agree on the answer yet so let’s discuss it!

The key to answering WDPTS? must be to reconstruct Earth’s tectonic history, using both first-order understanding of how large silicate bodies cool and proper interpretation of the rock record, particularly those mineral and rock assemblages that are diagnostic of plate tectonic records of independent plate motions, subduction and collision. One possibility is that Earth has always had plate tectonics. This follows from a strict interpretation of the Principle of Uniformity, which basically states that “the present is the key to the past”. Following strict Uniformitarianist logic, because we definitely have plate tectonics today, Earth must have always had plate tectonics. But strict adherence to Uniformitarianism is ridiculous, as Stephen Jay Gould pointed out in his first peer-reviewed paper (Gould, 1965). Uniformitarianism is very useful when you are trying to explain how the Earth came to be to a bunch of religious nuts who think the Earth is 6000 years old and that humans and dinosaurs coexisted, but it is not useful when trying to understand Earth’s tectonic history for the simple reason that it inhibits inquiry.

Earth is the only known silicate planet that has plate tectonics, so plate tectonics is probably a special way that viscous, rocky planets cool. Once we escape the Uniformitarianist straitjacket, we can see that a hotter early Earth may have cooled in a different way than the present Earth. Certainly we all know that there were different conditions in the Precambrian, which makes up 88% of all geologic time. We know that the interior of the early Earth was much hotter than that of today, for a number of reasons. For example, heat production due to radioactive decay at 4 Ga was ~3x that of today. Other causes of early heating include heat of accretion, the Sun’s T-tauri event (beginning of H fusion), core differentiation, and the Mars-size impact events. How much hotter was the early Earth? We don’t know but we do know that there are vanishingly few rocks from the first 800 Ma of Earth’s history, as expected for a hot early Earth.

Earth cooled sufficiently that 3.8 Ga rocks are fairly common (e.g. Greenland, Africa) but still, Earth must have been much hotter in the Archean than it is today. How did a hotter mantle affect our planet’s style of heat loss, i.e. tectonic style? Some conclude that a hotter mantle would have resulted in a greater total length of global spreading ridges, which means smaller plates and faster moving plates. Certainly a hotter Earth would have caused more extensive melting and thicker oceanic crust – komatiitic oceanic crust seems likely. It is also likely the oceanic lithosphere would have been thinner and more depleted and that the underlying asthenosphere would have been hotter. I surmise that Archean lithosphere would have been hotter, thinner, and less dense; it also would have been weaker and more prone to necking and breaking. These characteristics would have made it easier for sufficiently dense Archean lithosphere to trade places with buoyant Archean asthenosphere but this would have made subduction – which requires coherent plates – more difficult. We can (and should) stake out an opinion, but who knows for sure? Each of us should consider what we know about how our planet operates today and mentally explore how the hotter early Earth would have been similar or different than the plate tectonic Earth of today.

I discussed some of these issues with an eminent geoscientist, who argued that plate tectonics has always been operating on Earth. I asked him why he thought this and he replied “How else can you generate magmas and deform rocks?” There is no doubt that the Archean Earth witnessed a lot of igneous activity and deformation, maybe more than experienced by the modern Earth, but this does not require plate tectonics. This is vividly demonstrated by the examples of Venus and Mars, which today suffer intense deformation and magmatic activity but without plate tectonics.

For me, the most important evidence that Plate Tectonics operated at a given time interval is the preservation of ophiolites, blueschists, and ultra-high pressure (UHP) metamorphic terranes from a given time period somewhere on the globe. For those unfamiliar with what I call the “Smoking guns”* of Plate Tectonics’ (Fig. 1): ophiolites are fragments of oceanic crust and upper mantle (lithosphere) emplaced on continental crust (where geologists can study them). Ophiolites should have but sometimes lack extensive gabbros or sheeted dike complexes, but at a minimum an ophiolite should include tectonized harzburgitic mantle and pillowed tholeiite.

Figure 1: Histograms showing ages of preserved plate tectonic indicators for the last 3 Ga
of Earth history. Histograms are grouped into three types of plate-tectonic indicators: (a)
oceanic lithosphere (ophiolites), (b) subduction zone metamorphic products (jadeitites,
blueschists, and lawsonite eclogites), and (c) continental margins and collision zones
(gem corundum, UHP metamorphic rocks, and passive continental margins.                                           Modified from Stern et al. (in press).

Blueschists are fragments of oceanic crust that have been metamorphosed 40-60 km deep in the distinctive high-P, low T environment of a subduction zone. This produces the diagnostic Na-amphibole known as glaucophane. UHP terranes are slivers of continental sediments which have been subducted even deeper than blueschists, to depths of 100 km. Pressures like this are required to produce UHP-diagnostic phases of diamond or a high-P polymorph of SiO2 known as coesite. Both blueschists and UHP terranes require a two way ticket, down to be metamorphosed in a subduction zone, and back to the surface to be greeted by enthusiastic geologists. Excepting a few 1.9 Ga ophiolites, all three ‘smoking guns’ first appear in Neoproterozoic time, less than 1 billion years ago. I am very impressed by the fact that the vast majority of these three primary indicators of plate tectonics are so young, other geoscientists are less impressed (Fig. 2). More details about the nature of these three petrotectonic indicators can be found in Stern (2005) and Stern (2008).

Fig. 2: Different views about Plate Tectonic Smoking guns. My views are on the
left, the views of some/many other geoscientists are on the right.
Thanks to Julian Pearce for cartoon on right.

WTPTS? does not take up much of my research time but it is fun because it keeps me thinking about all the ways that Earth’s tectonic history can be interrogated. I wonder if there is some type of ore deposit or other rock association that could be used as a new plate tectonic indicator. Eclogites are also potential plate tectonic indicators. One type of eclogite forms when oceanic crust is metamorphosed at 50 km or more deep in a subduction zone but the term also can be used to describe any garnet-pyroxene rock produce by non-plate tectonic processes, for example in the lower continental crust as high-P cumulates or accompanying crustal thickening. Bob Coleman and colleagues wrote an interesting review entitled “Eclogites and Eclogites” that discussed some of these issues (Coleman et al., 1965). Subduction-related eclogites are a particular variety of clinopyroxene-garnet that contain Pyrope (Mg-Al) garnet and omphacite (jadeite-rich garnet). We need some kind of a “discrimination diagram” to distinguish subduction-related eclogites from those of other origins and then we could compile the distribution in time of subduction-related eclogites and use this as an independent petrotectonic indicator to help answer the question WDPTS? A few years ago, Tatsuki Tsujimori and co-authors looked at another subgroup of eclogites which must be subduction-related, those containing lawsonite (Tsujimori et al., 2006). Lawsonite is a hydrous calcium aluminum silicate that is typical of blueschist facies environments, and all known lawsonite-bearing eclogites are Phanerozoic (Fig. 1).

Another rock association that needs to be looked into for the purpose of addressing WTPTS? is the distribution of calc-alkaline batholiths through time. Batholiths mark the exhumed roots of magmatic arcs, exposed by a few km of erosion to remove the volcanic cover, and can be expected to persist as distinctive hallmarks of subduction until they are covered up by sediments. How can we recognize subduction-related batholiths in the rock record? We shouldn’t be happy with just a few trace element diagrams as sufficient to identify arc-like igneous rocks. Someone should develop a more robust set of characteristics and use these to define subduction-related batholiths. These characteristics should include a combination of geographic extent (how many km long and wide?), magmatic geochemical characteristics (e.g., K and isotopic gradients, and position relative to where the forearc basin and trench were (inferred from ophiolites, blueschists, and subduction-related eclogites), temporal features (subduction zones and thus magmatic arcs should be active for tens to hundreds of millions of years), and of course igneous rock compositions.

I continue to look for ways to interrogate the rock record for information about WDPTS? This investigation should be as broad as possible. I recently co-authored a Geology paper on the topic Plate Tectonic Gemstones (Stern et al., in press), which identified gemstones that are diagnostic of plate tectonic processes of subduction and collision. The subduction gemstone is Jade, which consists of nephrite (amphibole) and jadeite (pyroxene). Nephrite can form in other tectonic environments but jadeite only forms 25-70 km deep (0.8 – 2 GPa) under the cool (300-500°C) conditions found in subduction zones. All 19 known localities of jadeite are Phanerozoic in age (Fig. 1). The collision gemstone is ruby, which is gem corundum containing ~1% Cr2O3, an impurity that gives the gemstone its deep red color. Rubies form by hot metamorphism (500°- 800°C, 0.2 – 1.0 GPa), especially when passive margin sediments (esp. aluminous shales) get involved in continental collision. We summarized 32 ruby deposits and all but two are Neoproterozoic (Fig. 1). These gemstones are particularly useful because they form so deeply that erosion should reveal, not remove these. Our understanding of the global distribution of the gemstones ruby and jadeite are further indicators that subduction and collision – and therefore plate tectonics – are geologically young phenomena.

There should also be a way to use the temporal distribution of certain ore deposits to answer the question WDPTS? We haven’t made much progress in this aspect yet, but maybe someone will figure something out about this record. A while back I thought that porphyry copper deposits, which are clearly related to subduction, might be ‘smoking guns’ but now I understand that erosion is likely to remove all evidence of these deposits after a few tens of millions of years.

By now you have probably reached a point where you either think that there is some merit in these digital scribblings, or you may have concluded that I am full of unlithified coprolites. Regardless of what you think about WDPTS?, it must have begun at some time after Earth formed. I have shared my opinion about when this was, and some of the reasons for this opinion. Whenever “the great tectonic revolution” happened, there must have been a different tectonic style that it replaced. What was Earth’s pre-plate tectonic style?

To better understand Earth’s early tectonic style we must start from first principles. We know that the farther we go back in time, the hotter Earth’s mantle must have been. The lithosphere must have been correspondingly thinner and weaker and the asthenosphere must have been weaker and melted more extensively. Abundant mafic outpourings have loaded weak lithosphere, depressing it into the eclogite stability field (T>580°C, P>1.3 GPa) where the increase in density due to eclogitization would have stimulated further sinking, ultimately forming detached sinking diapirs, much as happens today during delamination. Archean greenstone belts must have been dominated by downwellings where weak lower crust delaminated and sank. The downwelling zones must have been flanked by mantle upwelling zones (Fig. 3). Hamilton (2007) concluded that dense mafic and ultramafic lavas erupted atop mobile felsic crust during the Archean produced a density inversion that led to the downfolding of volcanic rocks at the same time as domes of felsic middle crust flowed up and around the keel, resulting in the characteristic (keel-and-dome) structure of Archean greenstone belts. The lower panel on Fig. 3 summarizes one idea of what may have happened in the mostly “weak lithosphere vertical tectonics” of the early Earth.

Figure 3: Upper panel shows a simplified version of modern plate tectonics, driven
by the edgewise sinking of strong, dense lithosphere in subduction zones. Lower
panel shows a cartoon of how Earth’s tectonic regime might have been before plate
tectonics began. In a hotter Earth, thin, weak lithosphere sank vertically, similar to
modern scenarios of delamination or “drip tectonics”.

OK, enough ramblings. This brief essay has hopefully stimulated the reader’s interest in the grand question of when Earth’s modern tectonic regime was established. I encourage the reader to join the fun and excitement of this investigation. It’s easy to join and contribute to the discussion; we are just feeling our way around this problem. One route forward is to identify those rocks that, in your opinion, most likely formed by plate tectonic processes, and make these your “smoking guns” for plate tectonics. The occurrence of these through time may be an important indicator. It will also be fun to watch how this line of inquiry evolves and what new ideas are advanced over the next few years.

*’The term “smoking gun” was originally, and is still primarily, a reference to an object or fact that serves as conclusive evidence of a crime. In addition, its meaning has evolved in uses completely unrelated to criminal activity: for example, scientific evidence that is highly suggestive in favor of a particular hypothesis is sometimes called smoking gun evidence. Its name originally came from the idea of finding a smoking (i.e., very recently fired) gun on the person of a suspect wanted for shooting someone, which in that situation would be nearly unshakable proof of having committed the crime (from Wikipedia).

References:

Coleman, R.G., Lee, D.E., Beatty, L.B., and Brannock, W.W., 1965. Eclogites and Eclogites: Their Differences and Similarities. Bull. Geological Society America 76, 483-508.

Gould, S. J. 1965. Is Uniformitarianism Necessary? American Journal of Science 263, 223-238.

Hamilton, W.B., 2007, Earth’s first two billion years—The era of internally mobile crust, in Hatcher, R.D., Jr., Carlson, M.P., McBride, J.H., and Martínez Catalán, J.R., eds., 4-D Framework of Continental Crust: Geological Society of America Memoir 200, p. 233–296

Stern, R.J. 2005. Evidence from Ophiolites, Blueschists, and Ultra-High Pressure Metamorphic Terranes that the Modern Episode of Subduction Tectonics Began in Neoproterozoic Time. Geology 33,7, 557-560.

Stern, R.J. 2008. Modern-Style Plate Tectonics Began in Neoproterozoic Time: An Alternative Interpretation of Earth’s Tectonic History. Condie, K., and Pease, V., eds, When did Plate Tectonics Begin?: Geological Society of America Special Paper 440, 265-280.

Stern, R.J., Tsujimori, T., Harlow, G., and Groat, L. A., in press. Plate Tectonic Gemstones. Geology

Tsujimori, T., Sisson, V.B., Liou, J.G., Harlow, G.E., and Sorensen, S.S., 2006, Very low-temperature record in subduction process: a Review of worldwide Lawsonite eclogites. Lithos, doi:10.1016/j.lithos.2006.03.054.

Henry Shaler Williams

Initial Treasurer and Active Founder (sources: Cleland, 1919; Fairchild, 1932).

Personal. Henry Shaler Williams was born on March 6, 1847, in Ithaca, New York, and died of pleurisy in Havana, Cuba, on July 30, 1918. Williams’s paternal ancestors first settled in Connecticut in 1640, and his maternal ancestors, the Hardys, arrived in America shortly before the Revolution. It was Williams’s father who made the move to Ithaca. Williams attended the Ithaca Academy, and then graduated from Yale in 1868. He continued graduate studies there, receiving a doctorate in 1871. Although he had been interested in fossils as a boy and had studied paleontology and geology at Yale, Williams honored his father’s wishes to join him in business affairs in Ithaca, where he worked from 1872 to 1880. In 1879, however, Williams began an affiliation as Professor of Paleontology and Geology at Cornell University which he held until 1892. He then resigned to accept the Silliman Professorship of Geology at Yale (1892–1904). He returned to Cornell in 1904, where he remained until retirement in 1912. His last two years were spent developing oil prospects on a son’s property in Cuba. While at Cornell in 1885–1886, Williams was the founder of the science honorary, the Society of Sigma Xi.

Professional. Williams’s main lasting contributions were in paleontology and stratigraphy, particularly of Devonian strata in New York and adjacent states. He made careful and detailed examinations of the faunal content of many sections. By documenting changes in faunal content, both vertically and laterally, Williams demonstrated that faunas shifted as a reflection of migration. Thus, he was able to resolve long-standing problems in correlating the Devonian rocks in New York and eastern United States, and even to Europe. The methodology concerning biofacies that he established is still a mainstay of paleontological stratigraphy.

Role as a Founder. Williams was Secretary of the committee appointed at the American Association for the Advancement of Science (AAAS) Cincinnati meeting in 1881 to write a constitution for a proposed new geological society; Williams actually wrote most of the constitution, which was approved by the assembly, but further action was deferred. At the AAAS Cleveland meeting in August 1888, Williams was a member of the reconstituted committee to organize an American geological society. Williams apparently invited the geologists to Ithaca for the meeting of December 27, 1888, at which GSA was born, and Williams and his wife hosted the social gathering that followed. After the new society was established, Williams served GSA as its first Treasurer (1889–1891), as a member of the Council (1892–1894), as Second Vice-President (1903), and as First Vice-President (1904).

John James Stevenson

Initial Secretary and Active Founder (sources: White, 1925; Fairchild, 1932).

Personal. John James Stevenson was born in New York City on October 10, 1841, and died of pneumonia in New York on August 10, 1924.

His father, the Reverend Andrew Stevenson, emigrated from Ireland when he was 21 years old and settled in New York City in 1831. His mother, Ann Wilson, was born in Pennsylvania in 1811. Her ancestors had emigrated to America in 1777, settling originally in Delaware. Stevenson received his early education in private schools. He graduated from New York University in 1863 and earned a Ph.D. in 1867, the second graduate degree conferred by NYU.

Stevenson then visited various western mining regions on behalf of some friends who were interested in investment opportunities. In 1869 he became Professor of Chemistry and Natural Sciences at West Virginia University. While there he convinced I.C. White, another of the future GSA founders, to switch his undergraduate studies from medicine to geology. In 1871 Stevenson began an 11-year period of varied employment. He was an assistant (1871–1872) to J.S. Newberry, another future GSA founder, in the Geological Survey of Ohio. Then he served as a geologist with the U.S. Government Survey of the Colorado region, led by Lieutenant George M. Wheeler (1873–1874). He returned East from 1875 to 1877 to be assistant geologist to J.P. Lesley, the State Geologist in charge of the Second Geological Survey of Pennsylvania. Stevenson then once again worked for the Wheeler Survey in Colorado (1878) before doing some consulting work in Virginia and New Mexico (1879–1881), and finally returned to the Second Geological Survey of Pennsylvania (1881 to 1882). During 1882, Stevenson accepted a professorship at New York University, where he remained until his retirement in 1909.

Stevenson married twice. His first wife, Mary A. McGowan of Philadelphia, wed him in 1865 and bore him two girls and a boy. She died in 1871. He married his second wife, Mary C. Ewing of Uniontown, Pennsylvania, in 1879. She bore him a girl and a boy and survived him.

Professional. Stevenson is perhaps best known for his geologic studies of the Pittsburgh coal bed and associated strata in Ohio, Pennsylvania, and West Virginia, which mark the beginning of detailed coal-bed stratigraphy in American geology. His studies demonstrated that individual coal beds have distinctive characteristics that make them identifiable elsewhere, a tremendous aid in correlation. He is also known for his pioneering stratigraphic work for the Wheeler Survey in southern Colorado, where he determined that the Southern Rockies underwent a succession of uplifts over time, rather than the then-prevailing view of a single uplift. His stratigraphic work on the coal-bearing Cretaceous strata in New Mexico, also for the Wheeler Survey, was another giant step for coal-bed stratigraphy.

In addition to his work on behalf of GSA (below), Stevenson served as Vice-President of the American Association for the Advancement of Science  (AAAS) (1891), and President of the New York Academy of Sciences (1896–1898), and belonged to 35 foreign learned societies.

Role as a Founder. Stevenson was one of the most active of the founders of GSA. He was a member of the first committee appointed to consider organizing a geological society at the Cleveland meeting of AAAS on August 14, 1888. He served on the committee charged with writing a provisional constitution and reporting back to the assemblage the next day. He was also Secretary of the organizing committee that, in the following months, distributed the First Circular, and he prepared the Second Circular of organization of the new geological society in October-November 1888. When the new society was finally born on December 27, 1888, Stevenson was elected its first Secretary (1888–1890), and later served as a Councilor (1891), as Second Vice-President (1893), as First Vice-President (1897), and as President (1898).

On behalf of the Structural Geology and Tectonics Division I thank GSA for the opportunity to contribute to the Speaking of Geoscience blog commemorating GSA’s 125^th year. This contribution is a discussion of what constitutes the modern dimensions of Petroleum Structural Geology, the skills and experience that are desired in its practitioners, and recommendations for how the links between academia and industry can be made more productive. My principal ambition in writing this blog is to recognize that, while the Structural Geology and Tectonics Division is GSA’s largest division, there is an even larger group of structural geology professionals in the petroleum industry, many of whom have limited association with GSA.  The lines of communication between this group and GSA need strengthening.

One hundred and twenty five years ago the petroleum industry in North America was an awakening giant. Oil was flowing from surface anticlines in the foothills of the western Appalachians and the well control incident at the crest of a salt dome at what would become Spindletop Field in southeastern Texas was still 13 years away¹.  After decades of declining production in North America, 2012 saw the largest production increase ever² and, as a surprise to most watchers, the prospect of an energy independent and energy secure future for North America is predicted within most of our lifetimes³. While the traditional applications of qualitative and descriptive structural geology remain central to the story of industry development the quantitative and predictive aspects are growing in importance as the industry more routinely ventures into physically and environmentally challenging realms.

Petroleum Structure and Geomechanics (PSG) is one of the most important discipline areas in the petroleum industry. It is the science and application of analyzing deformation and stress within the petroleum realm by integrating outcrop, geophysical, remote sensing, petrophysical, core, laboratory rock strength, and fluid flow data. It spans spatial scales from tectonic reconstructions to SEM-imaged rock-fabrics. The outcome of this pursuit leads to a more complete understanding of the creation of petroleum habitats, formation and evolution of petroleum systems, formation and architecture of structural traps, and the internal architecture and stress state of reservoirs and their overburden.

While the need for customary applications of structural geology in the petroleum industry has not waned, in the last few years the importance of reservoir geomechanics has increased many-fold. Topics in this area include predicting the pore pressure environment; characterizing and modeling the coupled nature of deformation and fluid flow in stress-sensitive, faulted, fractured and compliant reservoirs; predicting and managing production-related deformation in reservoirs and their overburden to ensure operational integrity; deriving detailed models of subsurface stress and rock strength for horizontal drilling and stimulation of low permeability reservoirs; analyzing laboratory rock mechanics data and many other topics.

It is quite impossible for single individuals to be an expert in all of the topics stated above but a broad yet quantitative technical background is important for success as a PSG practitioner. It is important for PSG types to have as much experience as possible in these topics:

• structural analysis in the brittle realm
• global tectonics and continental margin geodynamics
• seismic interpretation
• outcrop characterization and mapping
• development of 3D digital models
• physical rock mechanics and reservoir geomechanics
• hydrology and fluid flow in porous media
• crustal heat flow
• remote sensing
• potential field interpretation
• seismology
• pore pressure

If at all possible, it is also valuable to have awareness of the topics of borehole petrophysics and reservoir engineering. Students are advised to not bypass any of the base sciences and obtain a firm background in chemistry, physics, calculus, statistics, and computational analysis.

With a view to strengthening the relationship between industry and academia, here are some suggestions for geoscience faculty: encourage your students to seek industry internships and careers, ask former students if you can visit them in industry for a week, invite company visits to your department, form and participate in an industry advisory board in your department and utilize alumni, seek an industry visit during a sabbatical, take short courses that industry people attend or teach, encourage industry-applied research in your department and among your peers, attend AAPG/SEG/SPE meetings and serve on their committees, promote professional student chapter associations and distinguished lecture programs in geoscience and related disciplines.

Industry professionals are encouraged to attend GSA meetings, visit academic departments and offer seminars and short courses, strive to make subsurface datasets available for research and teaching purposes, make time available for journal editorial service, and offer to serve on graduate student committees.

The Speaking of Geoscience blog offers a convenient forum to expand on this topic with additional discussion. I am interested in hearing what others think about the modern dimensions of Petroleum Structural Geology and how the links between industry and academia can be strengthened.

References

1. History of the petroleum industry in the United States

http://en.wikipedia.org/wiki/History_of_the_petroleum_industry_in_the_United_States

2. U.S. Oil-Production Rise Is Fastest Ever

http://online.wsj.com/article/SB10001424127887323468604578249621718888086.html

3. Spreading an Energy Revolution

http://www.nytimes.com/2013/02/06/opinion/global/spreading-an-energy-revolution.html

Peter Hennings is Manager of Structure and Geomechanics at ConocoPhillips, consulting professor of Geophysics at Stanford, adjunct professor of Geology at the University of Wyoming and is a GSA Honorary Fellow.

Alexander Winchell

Initial Second Vice-President and Active Founder (sources: Winchell, 1892a, 1892b; Fairchild, 1932).

Personal.  Alexander Winchell was born in the town of Northeast, New York, on December 31, 1824, and died of heart disease in Ann Arbor, Michigan, on February 19, 1891. His father, Horace Winchell, was descended from an Englishman who settled in Windsor, Connecticut, in 1635.  His mother, Caroline McAlister of Northeast, was of Scotch-Irish ancestry.

Alexander Winchell was the first-born son, and he benefited greatly in his early education by the fact that both his father and mother were teachers in the town’s public schools.  In 1840, at 16 years of age, he was determined to be a teacher and, with his father’s help, obtained a position in a district school. He taught while continuing studies until 1842, when he entered the Amenia Seminary.  Here he took his first course in geology, receiving a diploma in 1844.  He then enrolled at Wesleyan University at Middletown, Connecticut, still finding time to teach while studying for a degree, which he received in 1847.  He earned an M.A. degree in 1850.

From 1847 to 1853 Winchell taught in several academies or seminaries in New Jersey, New York, and most importantly, in Alabama.  His geologic studies in Alabama brought him an offer from the University of Michigan in 1853, where he became Professor of Physics and Civil Engineering, changing the next year to Geology, Zoology, and Botany.  He remained at the University (1853 to 1873 and 1879 to 1891) and was for part of that time the Director of the Michigan Geological Survey (1859 to 1861 and 1869 to 1871).  During his absence from the University of Michigan (1873 to 1879), Winchell was Chancellor and Professor of Geology at Vanderbilt University in Nashville, Tennessee.  He returned to Michigan as Professor of Geology and Paleontology and remained there until his death.

Alexander Winchell married the music teacher at Amenia Seminary, Julia F. Lines of Utica, New York, on December 5, 1849.  She and two of their six children survived him.

Professional.  Alexander Winchell was a noted geologist, educator, and administrator.  As a geologist, he initially made significant contributions to understanding the Cretaceous of Alabama, but his chief work was the paleontological and stratigraphical studies that defined the Michigan Basin and the salt- and petroleum-bearing strata therein, as well as later studies of the Archean rocks of the Lake Superior region.  As an educator, he made major contributions in popularizing geology and science in his drive to have geology included as part of pre-college curricula and to present geology so that the general public, including legislators, could understand it.  Both as a geologist and as an educator, he supported evolution as a valid concept and one which could be reconciled with religion.  Alexander Winchell was one of the group of geologists headed by his younger brother, Newton, who in January 1888 established the American Geologist, the first distinctively geological journal since 1814.

Role as a Founder.  Alexander Winchell was among the first of the active founders to propose the establishment of an American geological society and, more than anyone else, saw the effort through to its successful conclusion.  At the August 1881 meeting of the American Association for the Advancement of Science (AAAS) in Cincinnati, it was Alexander, along with his brother, who led the discussion about the desirability of organizing an independent American geological society.  After some years during which the idea was tabled, Alexander chaired the reactivated organizing committee that met in August 1888 at the AAAS meeting in Cleveland and approved the idea of a new society.  He continued as chairman of this committee during the succeeding months, culminating in the December meeting in Ithaca when the new society was formally approved and officers elected.  Alexander continued another year as chairman of the committee to revise the constitution.  Truly, Alexander Winchell could be considered the father of GSA, if anyone should be so acknowledged.  He also served GSA as the initial Second Vice-President (1889–1890) and as President (1891), though he did not live to complete his term.

This essay discusses one of my favorite field photos (Figure 1) and how it relates to the tectonics of the Pacific-North America plate boundary in the Gulf of California.  I like this photo for two reasons.  First, even people who don’t know much geology can usually pick out the faults in the picture.  Second, the rocks and their relationships in the photo have important implications for Miocene paleogeography and development of the Gulf of California rift.

Figure 1. View to the NW across part of the Main Gulf Escarpment in the southern Sierra San Pedro Mártir of Baja California, Mexico. Flat-lying mesas (including where the photographer is standing) are the ca. 12.5 Ma Tuff of San Felipe, which is a widespread pyroclastic density current deposit (ignimbrite) found on both sides of the Gulf of California. Beneath this tuff are, from top to base, deposits of the early to middle Miocene subduction-related volcanic arc; nonvolcanic sedimentary rocks; and Mesozoic tonalites of the Peninsular Ranges Batholith. Several major E-side-down normal faults offset the volcanic rocks and can be followed as vegetation lineaments within the tonalites.      Photo by the author.

The photo looks northwest at part of the Main Gulf Escarpment, which is the boundary between the unextended Peninsular Ranges of Baja California, on the west, and the tectonically extended mountain ranges within the Gulf of California Extensional Province, on the east (Figure 2).  North of the region of the photo, the Main Gulf Escarpment is controlled by the E-dipping San Pedro Mártir fault, which has an estimated normal offset of at least 5 km and a Holocene scarp about 80 km long that controls the very sharp, scalloped eastern edge of the Sierra San Pedro Mártir mountain range.  At the region of the photo, the escarpment is formed by a series of faults, including those shown in the photo and some further east that are to the right of the scene in the photo – see map by Stock (1993).

Figure 2. Shaded topographic and bathymetric map from GeoMapApp showing the northern part of the Baja California peninsula with Pacific Ocean to the west and Gulf of California to the east. Yellow box is location of photo shown in Fig.1.

Most of the rocks visible in the photo are tonalites of the Cretaceous Peninsular Ranges batholith (e.g., Ortega-Rivera, 2003).  The flat package of rocks, overlying the batholithic rocks, includes: a recessive basal layer of nonvolcanic sedimentary rocks, cliffy layers comprising conglomerates, tuffs, andesites, and lahar deposits derived from the early to middle Miocene subduction-related volcanic arc which lay to the east; and finally a ca. 12.5 Ma mesa-capping pyroclastic density current deposit (high-silica rhyolite, peralkaline ignimbrite) which Stock et al. (1999) correlated around this part of the Gulf Extensional Province and named the Tuff of San Felipe.  The relationships in the photo, borne out by regional work, suggest that there was a low-relief erosional surface on the batholithic rocks at the time of deposition of the early to middle Miocene arc rocks.  Regional mapping indicates that the faults postdate the volcanic deposits and that there was no topographic escarpment here when the Tuff of San Felipe was deposited (Stock et al., 1999).

The Tuff of San Felipe has now turned out to be a much more widespread unit than we ever expected when it was first documented in Baja California.  It apparently cooled during a magnetic field transition or field reversal, fortuitously acquiring a very unusual direction of remanent magnetization, shallow and slightly up, towards the SSW.  This unusually shallow paleomagnetic direction, along with the unit’s macroscopic characteristics (crystal-rich, with many lithic lapilli and a distinctive basal vitrophyre), its crystal content: 5-15% alkali feldspars, Fe-rich clinopyroxene, fayalite, Fe-Ti oxides, zircon (Vidal-Solano et al., 2008) and geochemistry (Vidal-Solano et al., 2013), allow detailed correlation of the outcrops in the region.  After correlation, the differences in declination of the remanence direction  constrain the rotations of the crustal blocks (e.g., Lewis & Stock, 1998; Oskin et al., 2001; Oskin & Stock, 2003; Bennett & Oskin, 2008; Bennett et al., in press).

The Tuff of San Felipe has now been correlated much farther than the mountain ranges in Baja California where it was initially identified – despite its problematic content of xenocrystic material complicating the geochronology (Vidal-Solano et al., 2005). Outcrops have been identified farther north, west and south on the Baja California peninsula (Bennett and Oskin, 2008; Olguin-Villa, 2010) as well as on the major Gulf of California islands (Tiburon Island, Isla Angel de La Guarda), on the eastern side of the Gulf, in coastal Sonora, and in quite a few mountain ranges farther inland in Sonora (see red dots and yellow dots in Figure 3)(e.g., Martin-Barajas et al., 2008; Vidal-Solano et al., 2005, 2008; Olguin-Villa, 2013).  The identified outcrops are distributed over a distance of about 450 km; the edges of the deposit are not known.  About 260 km of the distance can be blamed on the subsequent opening of the Gulf of California and a bit more on the extension in the Gulf Extensional Province in Baja California and Sonora.  Even so, it seems that this pyroclastic density current reached more than 100 km from the vent, in several different directions.   The volume of densely welded Tuff of San Felipe calculated from the Baja California side alone is about 125 km³ (Sabbeth & Stock, 2012). This suggests a Volcanic Explosivity Index of 7, which is why we refer to this as a mega-eruption.

Figure 3 . Outcrops of the Tuff of San Felipe, correlated by regional mapping, paleomagnetics, and geochemistry. The edges of the deposit are not known. The existing outcrop pattern covers a large area due to 1) Gulf of California plate motion and 2) outflow sheets (outcrops generally with a distinctive basal vitrophyre, shown by red dots) that traveled a long distance from the vent. Yellow dots are inferred to be vent locations based on unit thickness and basal characteristics, as well as trace element geochemical correlations (Vidal-Solano et al., 2013). As proposed by Vidal-Solano et al. (2013), vent offsets suggest a strike-slip fault buried inland in Sonora. H = Hermosillo.   C = Cataviña. IAG = Isla Angel de la Guarda. IT = Isla Tiburon. IF = Imperial Fault.         N= Nogales.

So what does this have to do with the Gulf of California rift? The pyroclastic density currents from the mega-eruption blanketed a low-relief landscape, and traveled in some alluvial channels, at a time when there was no rift topography or rift-related rocks here.  The tuff it left behind was, to first order, a widespread flat horizon that now serves as an unusually precise structural marker for all the rift-related vertical motion and rotation on both sides of the Gulf of California since ca. 12.5 Ma.     Where the Tuff of San Felipe is preserved, it records how much differential uplift has occurred since the eruption (e.g., 1.6 km in the region shown in Figure 4) – a very important observational constraint for any geodynamic models of the development of this part of the rift. Ongoing field work in Sonora is building the equivalent picture there for vertical motions and rotations, although outcrops are not as continuous because of the extensive younger cover in the coastal plain.  Note that from the Tuff of San Felipe alone, we can’t tell when the rifting started, but 6.1-6.4 Ma volcanic units here, near both shorelines of the Gulf of California, were deposited in a nonmarine setting and match back together after restoring about 260 km of opening across the basins of the northern Gulf of California (Oskin et al., 2001; Oskin & Stock, 2003).  Many Mexican and US investigators have done a great deal of additional work to further our knowledge of the evolution of the Gulf of California, and there are more interpretations and controversies related to that, which will have to wait to be discussed some other time.

Figure 4. Outcrops of the Tuff of San Felipe in Baja California, draped over an ASTER-derived DEM. Black line is approximate coastline of the Gulf of California. Elevation difference of outcrops from coast to the high part of the Sierra San Pedro Martir is 1.6 km. Scale ticks on edges of map: 5’ in latitude and longitude.

Many questions remain about the scenario of the mega-eruption.  Two vent locations separated by about 100 km are under investigation (Fig. 3).  The probable vent location near the Sonoran coast is extensively dismembered by faulting, requiring more field work to determine its dimensions, and look for a caldera caused by the eruption.  Recent geochemical results (Vidal-Solano et al., 2013) favor the model that the two vent locations were originally very close together and are now offset right-laterally along a strike-slip fault.  We might expect the mega-eruption to have produced a layer of ash, but we haven’t seen much ash associated with it in the vent region, and we are not aware of coeval ashes having been reported in the more distal zone.  Some other eruptions of comparable volume have had far-reaching climate effects, but we don’t know if this eruption did, or not.  And why did this mega-eruption take place here in this location at this time?  It’s unique in the Baja California/Sonora region in terms of size and timing, and several theories have been proposed, but the question is still debated.

As geologists, we should ask ourselves why it took so long for the mega-eruption deposits to be recognized.  Geologists doing reconnaissance had seen a lot of these outcrops, but they had not been able to correlate them.  First, very detailed mapping was needed to prove continuity, because the Pacific-North America plate boundary tectonics and Gulf of California opening led to an extremely faulted, discontinuous pattern of preservation of outcrops of the Tuff of San Felipe.  Second, the lateral facies changes and intermittently rheomorphic character of the tuff were sometimes misunderstood.  Third, the early K-Ar geochronology that was done on the tuff often gave different answers in different places, or when different types of samples were used.  Finally, geologists were not expecting to be able to correlate volcanic facies so closely from one side to the other of the Gulf of California.  What really made a major difference in the regional and cross-Gulf correlations was the use of magnetic remanence direction in conjunction with all the other observations.  As lots of us continue to work on this problem with all of these various methods, the details of the mega-eruption will, I hope, continue to be studied, refined, and debated.

These results would not have been possible without many investigators working together (based in Mexico, the USA, and Europe) and doing very complementary, multidisciplinary studies ranging from detailed field mapping to geochemistry, geochronology, and paleomagnetics.  I would like to thank the many collaborators who I’ve worked with in developing these observations, including Dr. Arturo Martin Barajas of CICESE in Ensenada, Baja California; and Dr. Francisco Paz Moreno and Dr. Jesus Roberto Vidal-Solano of Universidad de Sonora in Hermosillo, Sonora.  I thank my graduate students whose theses address the geology in or around the Gulf of California (Claudia Lewis, Mike Oskin, Elizabeth Nagy, Patricia Persaud, Jane Dmochowski, Steve Skinner); and lots of adventurous field assistants.  NSF provided much of the funding that led to these results.

I would like to end with a few thoughts.  There are many problems for which detailed field work is still essential; the structural geology/tectonics community must work to make sure that strong field training is emphasized for geology students even while they are developing as interdisciplinary earth scientists and using the latest techniques and tools.  We also need to communicate the utility and fascination of earth science to non-specialists, in whatever way possible.  So dig out your favorite geology photo, or use the one in this essay, and maybe you can start a conversation.

References:

Bennett, S.E.K., Oskin, M.E., and Iriondo, A., Transtensional Rifting in the Proto-Gulf of California Near Bahía Kino, Sonora, México, Geological Society of America Bulletin, in press, 2013.

S. E. Bennett and M. E. Oskin, “A new high-precision paleomagnetic reference vector from Mesa El Burro, Mesa Cartabon, and Mesa El Pinole, Baja California for the Tuff of San Felipe, a Miocene ignimbrite marker bed exposed in Baja California and Sonora, Mexico,” Eos, Transactions, American Geophysical Union, vol. 89, no. 53, Suppl., p. Abstract T11A–1852, Dec. 2008.

C. J. Lewis and J. M. Stock, “Paleomagnetic evidence of localized vertical axis rotation during Neogene extension, Sierra San Fermín, northeastern Baja California, Mexico,” Journal of Geophysical Research: Solid Earth, vol. 103, no. B2, pp. 2455–2470, 1998.

Martin-Barajas, A., J. Stock, M. Lopez-Martinez, and A. Chapman, Estratigrafía volcánica del Neogeno en la mitad norte de Isla Angel de la Guarda, paper presented at “Primer congreso sobre la evolución geológica y ecológica del noroeste de México”, Instituto de Geología, Estación Regional Noroeste, UNAM, Hermosillo, Sonora, 2008.

Olguín-Villa, A. E., Estudio físico y químico del volcanismo hiperalcalino en la región de Cataviña, Baja California. Tesis de Licenciatura, Universidad de Sonora, 84 pp, 2010.

Olguin-Villa, A.E., Establecimiento de la Estratigrafía Magnética del Evento Volcánico Hiperalcalino del Mioceno Medio en la Sierra Libre, Sonora, México, M.S. Thesis, University of Sonora, 2013.

A. Ortega-Rivera, “Geochronological constraints on the tectonic history of the Peninsular Ranges Batholith of Alta and Baja California; tectonic implications for western Mexico,” Special Paper – Geological Society of America, vol. 374, pp. 297–335, 2003.

M. Oskin and J. Stock, “Cenozoic volcanism and tectonics of the continental margins of the upper Delfin Basin, northeastern Baja California and western Sonora,” Special Paper – Geological Society of America, vol. 374, pp. 421–438, 2003.

M. Oskin, J. Stock, and A. Martin-Barajas, “Rapid localization of Pacific-North America plate motion in the Gulf of California,” Geology (Boulder), vol. 29, no. 5, pp. 459–462, May 2001.

L. Sabbeth and J. M. Stock, “Updated Isopach Map of the Tuff of San Felipe in Baja California, Mexico,” Geological Society of America Abstracts with Programs, vol. 44, no. 3, p. 2, 2012.

J. M. Stock, “Geologic map of southern Valle Chico and adjacent regions, Baja California, Mexico,” Map and Chart Series (Geological Society of America), vol. MCH076, pp. 11–11, 1993.

J. M. Stock, C. J. Lewis, and E. A. Nagy, “The Tuff of San Felipe; an extensive middle Miocene pyroclastic flow deposit in Baja California, Mexico,” Journal of Volcanology and Geothermal Research, vol. 93, no. 1–2, pp. 53–74, 1999.

J. Vidal Solano, F. A. Paz Moreno, A. Iriondo, A. Demant, and J.-J. Cocheme, “Middle Miocene peralkaline ignimbrites in the Hermosillo region (Sonora, Mexico); geodynamic implications,” Comptes Rendus – Academie des Sciences. Geoscience, vol. 337, no. 16, pp. 1421–1430, Dec. 2005.

J. R. Vidal Solano, H. Lapierre, J. M. Stock, A. Demant, F. A. Paz Moreno, D. Bosch, P. Brunet, and A. Amortegui, “Isotope geochemistry and petrogenesis of peralkaline middle Miocene ignimbrites from central Sonora; relationship with continental break-up and the birth of the Gulf of California,” Bulletin de la Societe Geologique de France, vol. 179, no. 5, pp. 453–464, Sep. 2008.

J. R. Vidal Solano, R. Lozano Santa Cruz, O. Zamora, A. Mendoza-Cordova, and J. M. Stock, “Geochemical characteristics of the extensive peralkaline pyroclastic flow deposit of NW Mexico based on conventional and handheld X-ray fluorescence. Geochemical and tectonic implications in a regional context,” Journal of Iberian Geology, in press, 2013.

Joann M. Stock is a Geological Society of America Fellow and Professor of Geology and Geophysics at the California Institute of Technology.

James Dwight Dana

Initial First Vice-President (sources: Le Conte, 1896; Hadley and others 1913; Fairchild, 1932).

(from The Founding of the Geological Society of America: A Retrospect on Its Centennial Birthday 1888–1988, by Arthur Mirsky)

Personal. James Dwight Dana was born in Utica, New York, on February 12, 1813, and died in New Haven Connecticut, on April 14, 1895.

Dana’s interest in science was fostered during his education at the Bartlett Academy at Utica, where his science teacher was Fay Edgerton, who had been a pupil of Amos Eaton, a pioneer American geologist. Dana entered Yale College at New Haven in 1830; there his science studies were influenced further by the elder Benjamin Silliman, under whom Amos Eaton had studied earlier. Upon graduating from Yale in 1833, Dana spent 15 months as a shipboard mathematics instructor for midshipmen of the U.S. Navy, during which time he cruised the Mediterranean. He studied volcanic phenomena there, and a letter describing his observations to Silliman appeared in the American Journal of Science in 1835; this was his first publication. In 1836 he was an assistant in chemistry to Silliman at Yale. From 1838 to 1842, Dana served as a naturalist responsible for geology and mineralogy, and later, for marine zoology, with the United States Exploring Expedition to the Pacific under the command of Lieutenant Charles Wilkes. In 1849 he was appointed a professor at Yale but, because he continued to work on his reports of the Wilkes expedition, he did not assume his teaching duties until 1855. He remained at Yale until his retirement in 1890. Dana married Professor Benjamin Silliman’s daughter, Henrietta, in 1844.

Professional. Dana’s System of Mineralogy, published in 1837 when he was just 24 years old, and his Manual of Mineralogy (1848), became the main introduction to mineralogy for generations of geology students. He also published his Manual of Geology in 1862, which for 40 years was a most influential textbook for beginning students of geology. In addition, he published many articles on a variety of geological and zoological topics. Most important among these were articles supporting the subsidence theory of the growth of coral reefs, originally suggested by Charles Darwin, and his studies of volcanism as one phase of a broader igneous activity associated with widespread but slow earth movements that determine the grand features of the Earth’s crust. Also, Dana named and expanded the geosynclinal concept, originated by James Hall in 1859, which became one of the main explanations of mountain building for the next 100 years. Dana was much honored by American geologists. In 1854, he was elected President of AAAS, and in 1890, as President of GSA.

Role as a Founder. Dana was in his mid-70s when GSA was born in 1888. Although Dana was not present at the Ithaca meeting on December 27 of that year, as a distinguished elder he had supported the efforts of American geologists to organize a geological society. When the new society was established, Dana was elected First Vice-President of the American Geological Society (1889), and the President of GSA (1890).

The Geological Society of America’s First Official Seal (1891-1935)

The formation of an American geological society was initially proposed at the 18 August 1881 meeting of the American Association for the Advancement of Science (AAAS). Seven years later, the concept was refocused. In June 1888, the AAAS Section E (Geology and Geography) journal American Geologist (created as a direct result of work by Geological Society of America [GSA] Founders and brothers Alexander and Newton Horace Winchell and others) issued a call for all American geologists to meet to consider the formation of an American geological society. The vote in August 1888 was positive, and on 27 December 1888, the first formal organization meeting of the American Geological Society was held at Cornell University in Ithaca, NY.  Thirteen original Fellows were present.  Elder statesmen James Dwight Dana, James Hall, John Strong Newberry, and John Wesley Powell served among the initial elected officers and councilors, undertaking “leadership roles to help nurture the infant society through its first year” (Mirsky, 1988, p. 8). The name of the society was changed to The Geological Society of America in 1889.

The American Geological Society’s active founders were as follows:

H.L. Fairchild – Rochester University, Rochester, NY
James Hall – State Museum, Albany, NY
C.H. Hitchcock – Dartmouth College, Hanover, NH
J.F. Kemp – Cornell University, Ithaca, NY
W.J. McGee – U.S. Geological Survey
H.B. Nason – Rensselaer Polytechnic Institute, Troy, NY
J.J. Stevenson – University of the City of New York, NY
I.C. White – West Viginia University, Morgantown, WV
H.S. Williams – Cornell University, Ithaca, NY
J.F. Williams – Pratt Technical Institute, Brooklyn, NY
S.G. Williams – Cornell University, Ithaca, NY
Alexander Winchell – University of Michigan, Ann Arbor, MI
N.H. Winchell – University of Minnesota, Minneapolis, MN

The first officers and councilors of the new society were:

President: James Hall, Albany, NY
First Vice-President: James D. Dana, New Haven, CT
Second Vice-President: Alexander Winchell, Ann Arbor, MI
Secretary: John J. Stevenson, New York, NY
Treasurer: Henry S. Williams, Ithaca, NY
Members-at-large of the Council:
Charles H. Hitchcock, Hanover, NH
John S. Newberry, New York, NY
John W. Powell, Washington, D.C.

When GSA joined the league of established American scientific societies, writes Mirsky, it was the only one devoted to geologists continent-wide. In terms of the publication and dissemination of geological findings and ideas, this was a monumental step. Prior to this point, publication, though prolific, was haphazard, and studies were mostly supported by geologists’ personal finances or that of their wealthy patrons. Government support for geological studies and publication became available after the establishment of the state geological surveys ca. 1830, but the U.S. still lagged behind its European counterparts. According to Mirsky, geologic articles appeared regularly in a variety of media covering an assortment of topics, but none had real continuity or regular scientific readership.

Genealogy of the Geological Society of America.                                                                         Note the early role of geologists in the founding of AAAS, from which GSA is derived.

One of the main reasons GSA was formed, especially in the eyes of the Winchell brothers, was to provide a platform for the publication of geologic papers, abstracts, and meeting proceedings, as well as other news aimed at geoscientists. Among the Society’s first decisions was to establish the Geological Society of America Bulletin (first published in February 1890) and to change the meeting dates for technical sessions from summer, when AAAS met, to a post-field season winter month.

GSA is celebrating its 125th Anniversary at its annual meeting in Denver, Colorado, USA, on 27–30 October 2013. As part of that celebration, this blog will publish a series of posts about GSA’s 16 “founding fellows.”

We begin with GSA’s first president, James Hall.

James Hall

Initial President and Active Founder

James Hall, 1811-1898. First President of the Geological Society of America, 1889.

Personal. James Hall (known to historians as James Hall, Jr.) was born in Hingham, Massachusetts, on September 12, 1811, and died of a stroke in Echo Hill, Bethlehem, New Hampshire, on August 7, 1898.

Hall’s father and namesake, when only 19 years old, left England for the United States. He met an equally young woman on the ship and, shortly after arriving in Boston, they were married. James Hall was their first son. He attended the public school in Hingham after which he went to Rensselaer Institute in Troy, New York, where he studied natural science under Amos Eaton, receiving his degree in 1832.

Hall’s early development as a geologist was greatly influenced by Eaton, who, upon Hall’s graduation, made Hall a librarian and, shortly after, an assistant professor at Rensselaer. Eaton introduced Hall to Stephen Van Rensselaer, who had supported Eaton’s own studies, and for whom Hall undertook his first systematic field work in geology. Van Rensselaer was favorably impressed by Hall and used his influence to get Hall an appointment in 1836 as an assistant to Ebenezer Emmons, who was one of four district geologists in the newly formed New York State Geological Survey. In 1837 Hall became a district geologist himself, and then State Paleontologist, and he remained devoted to the work of the Survey for the rest of his long life.

Hall married Susan Aiken, the daughter of a Troy lawyer, in 1838. She died in 1895, only three years before Hall. They had been married for 57 years. Four children survived them.

Professional. From his professional beginnings, James Hall was associated with New York geology, and after 1843 with the State Geological Survey in particular. Hall, however, did study areas outside of New York, and, in fact, was briefly State Geologist of Iowa and, later, of Wisconsin. Hall’s work greatly influenced the course of American geology. His major contributions were to apply detailed paleontologic studies to the physical stratigraphic column in order to solve long-argued problems in Paleozoic correlation. The impact of his work affected geological studies across the United States and Canada and even to Europe. Also, in 1859 Hall originated the concept that mountain systems were derived from slowly sinking basins that filled with sediments (later named geosynclines by J.D. Dana), a concept that proved to be one of the main explanations of mountain building for 100 years. Hall’s work was recognized everywhere. He was an officer and a prominent member of several geological societies in the United States as well as Europe. Most noteworthy perhaps was his presidency of AAAS in 1856 and his presidency of the then just-formed American Geological Society in 1889.

Role as a Founder. Hall was in his 70s during the decade of the 1880s, which culminated with organization of GSA. The main voices in the efforts to organize and American geological society from 1881 to 1888 belonged to younger geologists. But such efforts benefited greatly by the support of recognized “elder statesmen” in the geological profession. Hall was at the Ithaca meeting in 1888 and was honored by being elected as the first President of GSA (and the only President under GSA’s first-year name, The American Geological Society).

References

Eckel, E.B., 1982, The Geological Society of America: Life history of a learned society: Geological Society of America Memoir 155, 168 p.

Fairchild, H.L., 1932, The Geological Society of America, 1888-1930; A chapter in earth-science history: Geological Society of America, 232 p.

Mirsky, A., 1988, The Founding of The Geological Society of America: A Retrospect on its Centennial Birthday, 1888-1988: Geological Society of America, 60 p.

Stevenson, J.J., 1898, Memoir of James Hall: Geological Society of America Bulletin, v. 10, p. 425-436.