GSA TODAY • 2000 Medalists, Awardees, P

Vol. 10, No. 8 August 2000 INSIDE • Officer and Councilor Nominees, p. 9 GSA TODAY • 2000 Medalists, Awardees, p. 19 • Fellows, Members, p. 29 A Publication of the Geological Society of America • Student Associates, p. 34 Impact Events and Their Effect on the Origin, Evolution, and Distribution of Life

David A. Kring, Department of Planetary Sciences, University of Arizona, 1629 E. University Blvd., Tucson, AZ 85721, USA, [email protected]

ABSTRACT Impact cratering has affected the geologic and biologic evolution of Earth, from the earliest stages of accretion to the present. The environmental consequences of impact cratering and their biologic repercussions are illustrated by the Chicxulub impact event and its link to the Cretaceous-Tertiary (K-T) mass extinction event. While smaller impact events are more common, there were probably four to five additional impact events of this size during the Phanerozoic. These types of large impact events, and even larger ones, occurred more frequently earlier in Earth history. A particularly intense period of bombardment appears to have occurred ~3.8–3.9 Ga, corresponding to the earliest isotopic traces of life on Earth. These impact events may have made it difficult for preexisting life to survive or may have provided the necessary environmental crucibles for prebi- otic chemistry and its evolution into life.

INTRODUCTION It has become increasingly clear that impact cratering has affected both the geologic and biologic evolution of our planet. Although this view has its roots in the Figure 1. Earthrise over Smythii impact basin with Schubert impact crater on horizon. Views like this Apollo era (Fig. 1; McLaren, 1970), it was during Apollo missions made it clear that Earth is part of a planetary system rather than an isolated not widely recognized until studies linked sphere, subject to the same bombardment that battered the surface of the Moon. (Apollo 11 AS11-44- the mass extinction that defines the end 6551) of the Mesozoic Era with the Chicxulub impact event (L.W. Alvarez et al., 1980; Hildebrand et al., 1991). That particular tile, and the ambient conditions on Earth organism’s ability to adapt (Newell, 1962). event also illustrates how a process that at the time of impact. Consequences can When the environmental effect is largely destroys some organisms can create oppor- range from the death of individual organ- regional, the changes must overwhelm the tunities for other organisms—in this case isms to the complete extinction of species. migratory capacity of a species or last leading to distinctly different ecosystems While the former can be the direct result longer than its dormant capacity. When during the Cenozoic Era. This dual pattern of an impact event (e.g., shock wave– the effect transcends geographical bound- of disaster and opportunity has existed induced hemorrhaging and edema in an aries and becomes global, the change must with impact events throughout Earth his- animal’s lungs [Kring, 1997]), the more be rapid relative to the time scale of evolu- tory, even during the earliest development important biological effect, including tionary adaptation or, again, last longer of life. extinction, will be through impact- than the dormant capacity of a species. The biologic consequences of impact generated environmental changes. To be The minimum types of impact events cratering depend on many factors, includ- an effective extinction mechanism, the needed to exceed these extinction thresh- ing the energy of the impact event, the environmental changes need to extend type of target materials, the type of projec- throughout a habitat range and exceed an Impact Events continued on p. 2 GSA TODAY August IN THIS ISSUE Vol. 10, No. 8 2000 Impact Events and Their Effect GSA Names 2000 Medal and Award GSA TODAY (ISSN 1052-5173) is published monthly on the Origin, Evolution, and Recipients ...... 19 by The Geological Society of America, Inc., with offices at 3300 Distribution of Life ...... 1 Penrose Place, Boulder, Colorado. Mailing address: P.O. Box Field Forum Report ...... 20 9140, Boulder, CO 80301-9140, U.S.A. Periodicals postage In Memoriam ...... 2 Penrose Conference Scheduled ...... 22 paid at Boulder, Colorado, and at additional mailing offices. 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George W. Berry (1915–1999) Alan S. Horowitz (1930–1999) CORRECTION: The fax numbers for D.L. Blackstone Jr. N. Gary Lane and Donald E. Hattin registering for the 2000 GSA Annual Eugene N. Cameron (1910–1999) William Hilton Johnson Meeting in Reno are 303-443-1510 John M. Guilbert (1935–1997) or 303-447-0648. An incorrect Allan F. Schneider and Ardith K. Hansel Frederick William Cater Jr. number was published on page 50 (1912–1998) Lincoln Ridler Page (1910–1996) of the June issue of GSA Today. Chester A. Wallace James W. Skehan Jesse LeRoy Dally (1923–1999) Frank Stanton Simons (1917–1995) David J. Dally Warren B. Hamilton GEOTRIP CANCELLATION: “Giant Edwin Lee Hamilton (1914–1998) Laurence L. Sloss (1913–1996) Steps Through Time,” scheduled for Edwin C. Buffington, Joseph R. Curray, W. Arthur White (1916–1998) September 16–October 1, 2000, has and David G. Moore Randall E. Hughes and D.M. Moore been cancelled. Bruce B. Hanshaw (1930–1998) Jack H. Medlin, Dallas Peck, John Keith, Eugene Robinson, and Blair Jones

et al., 2000) were also affected by the listic trajectories, enveloping the whole nental surface temperatures (Toon et al., splashdown of impact ejecta, density cur- Earth as it fell back into the atmosphere. 1982; Covey et al., 1990). rents, and seismically induced slumping of The impact ejecta was distributed globally In addition to the dust in the vapor- coastal margins (e.g., Smit et al., 1992) fol- in a pattern much different from that of rich plume of ejecta, several important gas lowing magnitude 10 earthquakes (Kring, volcanic plumes, which simply rise into species were entrained. The Yucatán 1993). Within a few hundred kilometers of the stratosphere and then spread into lati- Peninsula, near the Chicxulub impact site, the Chicxulub crater, the thick blanket of tudinal bands. Calculations indicate that consists of carbonate and anhydrite ejecta was sufficient to exterminate life. most of this material reaccreted to the top deposits that overlie a crystalline silicate of the atmosphere over a three-day period basement, so the impact produced several Global Effects (Durda et al., 1997), where it then settled climatically active gas components, While these effects devastated organ- to the ground over a longer period of including aerosol-producing SO2 and SO3, isms in the Gulf of Mexico region, the time, depending on grain size. If a sub- greenhouse-warming CO2 and H2O, and most significant environmental perturba- stantial portion of this dust was submi- ozone-depleting Cl and Br (e.g., Brett, tions were the direct and indirect result of cron in size, model calculations suggest 1992; Pope et al., 1997; Pierazzo et al., ejected debris that rained through the the dust may have made it too dark to see 1998; Yang and Ahrens, 1998; Kring, atmosphere, as first postulated by L.W. for one to six months and too dark for 1999). The worst appears to have been the Alvarez et al. (1980). This material was photosynthesis for two months to one S species, which enhanced stratospheric S carried in a vapor-rich plume that rose year, seriously disrupting marine and con- through the atmosphere into space. Once tinental food chains and decreasing conti- above the atmosphere, it expanded on bal- Impact Events continued on p. 4

GSA TODAY, August 2000 3 chemical reactions that occurred have not been modeled. On the ground, however, it is clear there were postimpact fires. Charcoal and soot, which are produced when vegetation or fossil carbon are burned, have been found in K-T boundary sediments around the world (e.g., Tschudy et al., 1984; Wolbach et al., 1990). Theoretical calculations suggest these fires were ignited by intense thermal radiation produced by ejecta reentering the atmosphere on ballis- tic trajectories (Melosh et al., 1990). Fires consumed large quantities of latest Creta- ceous vegetation, burned many animals, and robbed herbivores of their food. Fires would have produced several secondary effects too, absorbing sunlight, possibly inhibiting photosynthesis, lowering atmospheric temperatures, and producing organic pyrotoxins (Wolbach et al., 1990). Figure 2. Relative time scales of several environmental perturbations caused by Chicxulub impact event. As this brief review illustrates, several impact-caused perturbations on the ground and in the atmosphere could have contributed to the K-T boundary extinc- Impact Events continued from p. 3 sphere (N O), carbonates dissolved by 2 tions (Figs. 2 and 3). However, it was likely acidic waters (CO ), and wildfires (CO 2 2 the combination of primary and sec- and N O; discussed later). However, the on the order of 105–106 times relative to 2 ondary effects that was so deleterious. magnitude of greenhouse warming is still modern abundances. Different parts of the global environment uncertain. Sulfate aerosols were converted to sul- would have been perturbed over diverse In addition, ozone-depleting Cl and furic acid rain, whose effects compounded time scales (e.g., days for reentering Br were produced from the projectile, tar- those produced by nitric acid rain. Nitric impact ejecta, months for dust in the get water, target sedimentary rocks, target acid rain was produced from nitrous stratosphere, and years for sulfate acid basement rocks, and postimpact wildfires. oxides that were created when the atmo- aerosols). The initial effects would be The amount of Cl injected into the stratosphere was shock-heated by the impact added to and amplified by secondary sphere is believed to be five orders of mag- event (Lewis et al., 1982; Prinn and Fegley, effects and the ensuing collateral damage. nitude greater than that needed to destroy 1987; Zahnle, 1990). Acid rain could have The biological consequence of the the modern ozone layer (Kring, 1999). defoliated continental vegetation and Chicxulub impact was the collapse of However, this issue illustrates the current even aquatic plants in shallow, inade- entire ecosystems; cascading effects uncertainty of postimpact atmospheric quately buffered lakes or seas whose entire destroyed the infrastructure of the bio- conditions. While ozone may have been water columns became acidic. Asphyxia- sphere (e.g., collapse of food chains, loss consumed by reactions with Cl, Br, and tion of animals by nitrous oxides and of habitat), compounding the initial direct NO, reactions with dust and smoke parti- toxic poisoning by metals acid-leached environmental effects. Thus, while the cles, and heating by reentering debris and from the ground have also been suggested physical effects of the impact event may accompanying thermal radiation and (Prinn and Fegley, 1987), possibly com- have been relatively short-lived, the time increased solar absorption, the effects may pounding the toxic effects of metals from needed to reestablish chemical gradients, also have been miti- the projectile (Erickson and Dickson, gated by ice, 1987). The amount of sulfuric acid was which briefly not, however, large enough to acidify enhances plane- oceans (D’Hondt et al., 1994; Pierazzo et tary albedo, dust al., 1998). The nitric acid production may and smoke, have produced a pH of 3–4 in the upper which absorb 100 m, if maximum estimates are correct, solar radiation, but this also seems unlikely (D’Hondt NO , which et al., 1994). 2 strongly absorbs Sulfate aerosols significantly reduced part of the ultra- the amount of sunlight reaching Earth’s violet spectrum, surface and would have, thus, enhanced and sulfate the effects of ejected dust particles and aerosols, which soot produced by fires (discussed later). scatter solar radia- Darkness and cooler temperatures pro- tion. At the duced by these particles were relatively moment, there is short-term, lasting only a few years. On a good list of the the other hand, there may have been a perturbing ele- longer-term increase in temperatures ments injected because a large quantity of greenhouse into the atmo- gases were produced from vaporizing sedi- sphere, but the ments (CO and H O), the projectile (CO 2 2 2 complex micro- and H O, depending on the type of aster- 2 physical and Figure 3. Thermal excursions produced by Chicxulub impact event as a func- oid or comet), shock heating of the atmo- tion of time. Preimpact ambient temperature is marked with a dashed line.

4 GSA TODAY, August 2000 Figure 4. Maps showing regions of the Moon that were resurfaced during Nectarian Period (brown) and Imbrian Period (blue), and outlines of larger basins. Also shown are pre- Nectarian units (darkest brown) and areas of unclear stratigraphic relationships (gray) (Wilhelms, 1987).

repair food chains, and rebuild integrated depending on the preimpact plant com- larger than Chicxulub (Fig. 4; Wilhelms, ecosystems was much greater. munity, suggesting the vegetation recov- 1984, 1987). The number of impacts The details of the biologic crisis and ered from local seeds and spore, rather occurring on Earth would have been an its recovery are difficult to tease from the than being repopulated from distant com- order of magnitude larger, implying geologic record, but some progress is being munities (Sweet and Braman, 1992). Gym- >10,000 large impact events. This was fol- made. Impact cratering theory suggests nosperms were generally lost at the lowed by the Early Imbrian Epoch, which the crisis was global and, indeed, marine boundary, suggesting the swamp forest began with the Imbrium impact and bivalve extinction intensities are global canopy was destroyed for several years ended with the Orientale impact, again without any latitudinal or geographic vari- (Sweet and Lerbekmo, 1999), even at sites roughly 3.8–3.9 Ga, producing additional ations (Raup and Jablonski, 1993). In both ~4000 km from the impact. basin-size craters on the order of 1000 km marine and continental settings, organ- diameter. These large impact events also isms with dormant or resting states faired LIFE’S ORIGINS produced swarms of secondary craters better through the crisis. For example, with diameters >20 km (e.g., Wilhelms, The Chicxulub event is an example of planktonic diatoms that produce resting 1987), which were also large enough to how impact cratering can affect life and is spores specialized to persist in benthic or cause dramatic effects. Impact events of likely to be only one of five to six such deep-pelagic environments of low- to no- these sizes on Earth would have been large events during the Phanerozoic (Kring, light conditions, and, during periods of enough to have affected the environment 1995). Impact cratering also had an impor- stress, had a high survival rate (Kitchell et and most likely any life that had arisen. tant effect much earlier in Earth history al., 1986). It has also been suggested that The largest impact events probably pro- when life was initially being established. the loss of primary productivity and the duced immense quantities of ejecta, tem- A particularly intense period of bombard- subsequent collapse of food chains had porarily charged the atmosphere with ment appears to have occurred ~3.9 Ga, much less an effect on organisms that silicate vapor, and boiled away large quan- which almost completely reset the U-Pb were detritus feeders or starvation resistant tities of surface water (Sleep et al., 1989; system in lunar highland samples in the (Sheehan et al., 1996). The recovery of Sleep and Zahnle, 1998). Apollo collection (Tera et al., 1974). The these survival species, however, did not Interestingly, the earliest isotopic event also seems to have put an upper represent the full recovery of the ecosys- evidence of life on Earth comes from this limit on the ages of surviving impact tem with robust food chains and atten- same period of time (e.g., Mojzsis and melts in the Apollo collection (Ryder, dant biochemical gradients. For example, Harrison, 2000). In addition, ribosomal 1990; Dalrymple and Ryder, 1993). While it appears that while marine production RNA analyses of the most deeply branch- the concept of a cataclysm has been con- may have recovered relatively quickly ing organisms suggest that life is rooted troversial (Baldwin, 1974; Hartmann, (albeit with a completely different popu- among thermophilic or hyperthermo- 1975), recent analyses of impact melts in lation of organisms), the flux of organics philic forms. Commonly, this is inter- lunar meteorites (Cohen et al., 2000), to the deep sea took approximately three preted to mean that life originated (or sur- which represent a much larger fraction of million years to recover (D’Hondt et al., vived the impact bombardment in) the Moon, have the same age limit and 1998). volcanic hydrothermal systems. However, support a planetwide impact cataclysm. Among plants in the western interior during the period of bombardment, The initial stage of intense impact of North America, the record of survival impact-generated hydrothermal systems cratering on the Moon is known as the and recovery is marked by a dramatic were possibly more abundant than vol- Nectarian Period (3.8–~3.9 Ga), which increase in the ratio of fern spore to canic ones. The heat source driving these began with Nectaris impact and ended angiosperm pollen (Orth et al., 1981; systems is the central uplift and/or pools with Imbrium impact (Wilhelms, 1987). Tschudy et al., 1984). The pioneering of impact melt. In the case of a Chicxulub- This period is believed to have been <200 behavior of the ferns after the impact- size event (among the smallest ~3.9 Ga), Ma long (Tera et al., 1974; Wilhelms, generated wildfires is similar to their melt pools may have driven a hydrother- 1987), during which time at least 1700 behavior after forest fires today. In mal system for 105 yr (Kring, 1995). The craters >~20 km diameter were produced, Canada, both ferns and angiosperm taxa including at least 12 impact basins far Impact Events continued on p. 6 behaved in an opportunistic fashion

GSA TODAY, August 2000 5 Sara Foland, CEO

“To learn geology one must travel widely and observe carefully, for geology is learned through the soles of your shoes, not the seat of your pants! The Earth is vast, its features, varied. One must climb mountains, travel over limitless plains, watch the waves of the sea beat unendingly upon the shore, study the work of mountain torrents as they carry their load to the sea, and learn to read the character of the rock record to understand the Earth. Delve deeply into the rocks, for truth is hidden there. Take heed to observe carefully the seemingly insignificant things, as each and every phenomenon and event is an integral part of nature’s process. Be untiring in your zeal to learn; and when you have accumulated facts, give careful thought to their interpretation. Let all your work be marked by ceaseless patience, tireless industry, vigilant caution, and prolonged study. Nature’s deeds are not erratic. What occurs is ruled by laws. When one is trained to read the geologic record, the deeds of nature © Paul Abdoo become clear, usually simple, and amenable to understanding and description. The Earth gives no higher or nobler task than to study nature, to unlock her secrets and interpret her deeds.” —Walter L. Manger et al. University of Arkansas Sigma Gamma Epsilon Initiation Ceremony

Service at GSA: Support for Students Julie: Interacting at these meetings with professional members from so Over the past several months, many different environments has helped us get a sense of “career.” It has we’ve talked about GSA’s values of sci- helped with everything from making a commitment to the field of geol- ence and stewardship. This month, ogy to developing interests in specific sub-disciplines and formulating we’re ready to look at the third of our career plans. All those exhibitors at meetings make gathering information three Ss, which is service. One signifi- easy, and travel grants help with the cost of getting there on a student cant form of service GSA and its mem- budget. bers perform is support for the profes- Jack: The mentoring sessions have been particularly useful. I’ve talked sional growth and development of one-on-one with people working for the U.S. Geological Survey, environ- young geoscientists. mental consulting firms, and in the petroleum industry. I’ve asked what Exploring this topic with me are their jobs were like, what they’d do if they were just starting out, and Jack May and Julie Williams May, both whether continuing my education to the Ph.D. level is worthwhile. The spring 2000 graduates of the Univer- sessions also covered practical matters like résumé writing. sity of Arkansas. Julie earned a B.A. in geology and a B.S. in earth science Sara: In fact, GSA’s mentoring programs are intended to give you per- (cum laude); Jack received his M.S. in spective and the skills you need in addition to your geoscience expertise. geology. They married in May and In funding these programs, I think Roy Shlemon was looking for a way to now live in Columbia, South Carolina, help young geoscientists begin making the transition from student to where Jack is pursuing a Ph.D. in geol- professional. ogy and Julie a master’s degree in envi- Jack: Certainly another growth experience for me came from presenting ronmental resource management at some of my research on sedimentation on the California continental bor- the University of South Carolina. derland at a poster session in Denver last year. Jack May and Julie Williams May Sara: I started out as a student mem- Sara: Many of us had our first sweaty-palm experience presenting ber of GSA, and I remember how valu- research at a GSA meeting. Section meetings are particularly good for this able that experience was for me. What stands out for you about member- because you can present to peers and faculty from outside your home ship in GSA? institution in a relatively small and somewhat informal venue. The great Jack: We’ve been student members for the last three years, and GSA has thing is that everyone wants you to succeed and people are extremely provided us with lots of opportunities to interact with geologists in indus- supportive. A related aspect of GSA’s support for students is our research try, academia, and government research. We attended the 1999 South- grants program. Since the program began in 1933, GSA has awarded Central Section meeting in Lubbock, the 1999 annual meeting in Denver, more than $7 million to 6,800 students. and this past spring we helped host the South-Central Section meeting in Julie: Jack and I have certainly enjoyed and benefited from our participa- Fayetteville. tion in GSA, and we intend to be lifetime members. See you in Reno!

Impact Events continued from p. 5 probably vented subaqueously, like those Chicxulub impact event 65 Ma, a large in volcanic crater lakes or deep-sea vents. number of regional and global environ- dimensions of these systems can extend In addition to providing a suitable envi- mental effects were generated that were across the entire diameter of a crater and ronment for thermophilic and hyper- likely the cause of the mass extinction down to depths in excess of several kilo- thermophilic forms of life, it has been that marks the K-T boundary. The poten- meters (e.g., Komor et al., 1988; Pevzner et suggested that the impacting objects may tial for disrupting the environment was al., 1992). Large regions within these sys- have seeded the surface of Earth with larger and more frequent earlier in Earth tems should have had appropriate temper- amino acids and other important organic history, particularly ~3.9 Ga when life atures for thermophilic and hyperther- materials (e.g., Chyba, 1993; Pierazzo and with thermophilic and hyperthermophilic mophilic organisms. When the craters Chyba, 1999). characteristics evolved. This implies that were subaerially exposed, the hydrother- life either originated in these impact- mal systems probably vented in mud pots, CONCLUSIONS dominated conditions or possibly that hot springs, and geysers, similar to those these forms of life were the type best Impact cratering is a very energetic in volcanic terranes. When the craters suited to survive this brief period of geologic process that has the capability of were filled with freshwater lakes or marine intense bombardment. In the latter case, disrupting or redirecting the biologic evo- incursions, the hydrothermal systems life may have originated under different lution of a planet. In the case of the

6 GSA TODAY, August 2000 1991, Chicxulub Crater: A possible Cretaceous-Tertiary Tertiary boundary: Earth and Planetary Science Letters, conditions in different environments and boundary impact crater on the Yucatán Peninsula, Mex- v. 83, p. 1–15. only found itself frustrated by impact cra- ico: Geology, v. 19, p. 867–871. Raup, D.M., and Jablonski, D., 1993, Geography of end- tering (Maher and Stevenson, 1988; Hildebrand, A.R., and Boynton, W.V., 1990, Proximal Cretaceous marine bivalve extinctions: Science, v. 260, Chyba, 1993) as it was by Chicxulub. Cretaceous-Tertiary boundary impact deposits in the p. 971–973. Caribbean: Science, v. 248, p. 843–847. Ryder, G., 1990, Lunar samples, lunar accretion and the ACKNOWLEDGMENTS Kitchell, J.A., Clark, D.L., and Gombos, A.M. Jr., 1986, early bombardment of the Moon: Eos (Transactions, Biological selectivity of extinctions: A link between American Geophysical Union), v. 71, p. 313, 322–323. background and mass extinction: Palaios, v. 1, I thank Maria Schuchardt at the Space Sheehan, P.M., Coorough, P.J., and Fastovsky, D.E., p. 504–511. Imagery Center, University of Arizona, for 1996, Biotic selectivity during the K-T and Late Ordovi- assistance with the figures. I also thank Klaus, A., Norris, R.D., Kroon, D., Smit, J., 2000, Impact- cian extinction events, in Ryder, G., et al., eds., The Cre- induced mass wasting at the K-T boundary: Blake Nose, taceous-Tertiary event and other catastrophes in Earth Richard Grieve, at Natural Resources western North Atlantic: Geology, v. 28, p. 319–322. history: Boulder, Colorado, Geological Society of Amer- ica Special Paper 307, p. 477–489. Canada, and Steven D’Hondt, at the Uni- Komor, S.C., Valley, J.W., and Brown, P.E., 1988, Fluid- versity of Rhode Island, for their help with inclusion evidence for impact heating at the Siljan Sleep, N.H., Zahnle, K.J., Kasting, J.F., and Morowitz, the manuscript. Ring, Sweden: Geology, v. 16, p. 711–715. H.J., 1989, Annihilation of ecosystems by large asteroid impacts on the early Earth: Nature, v. 342, p. 139–142. 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GSA TODAY, August 2000 7 Penrose PENROSE CONFERENCE REPORT CONFERENCE Volcanic Rifted Margins

Conveners: M.A. Menzies and C. Ebinger, Department of Geology, Royal Holloway, University of London, Egham, Surrey TW20 OEX, England, UK S. Klemperer, Department of Geology, Royal Holloway, University of London, Egham, Surrey TW20 OEX, England, UK, and Department of Geophysics, Stanford University, Stanford, CA 94305-32215, USA

Active rifting (plume-driven) models the absence of rifting which lead to forma- are the traditional explanation for the for- tion of intraplate large igneous provinces mation of volcanic rifted margins with sig- in ocean basins (e.g., Ontong-Java oceanic nificant surface uplift occurring prior to plateau) and on continents (e.g., Siberian flood volcanism and break-up extension. flood basalts). However, recent research on volcanic rifted margins indicates that their evolu- Continental Flood Volcanism, tion is more complex than that defined by Underplating and Seaward- earlier models, and several hybrid models Dipping Reflector Sequences have been proposed. At the Penrose 2000 Volcanic rifted margins are character- Volcanic Rifted Margin Conference held at ized by subaerial volcanic rocks (~4–6 km Royal Holloway, University of London, thick) on a continental margin. Ar-Ar and discussion centered on the margins of the Deccan volcanic stratigraphy exposed by scarp retreat at K-Ar dating indicates that, in the majority north, central, and south Atlantic Ocean, King Arthur’s Seat, Mahabaleshwar. of volcanic rifted margins, 70%–80% of the western and eastern coasts of Aus- the subaerial mafic and/or basaltic volcan- tralia, the southern Red Sea, the west coast ism occurred over a relatively short period thickness-time relationships reveal a of India and its conjugate margins in of time (2 m.y. in the case of the Red Sea marked decline in eruption rate from the Madagascar and the Seychelles. The char- and East Greenland plateau lavas and <0.5 mafic to the felsic eruptive stages of vol- acteristic features of volcanic rifted mar- m.y. in the case of the Deccan). The short canic rifted margins. This is consistent gins were summarized and it was agreed phase of basaltic volcanism is followed by with the requirement for longer time peri- that formation of a volcanic rifted margin a lengthy period of silicic volcanism that ods to allow basaltic magmas to pond in required complete rifting of a continent to can last for 5–10 m.y. In some volcanic shallow magma chambers and to evolve form an ocean above an upper mantle rifted margins, silicic volcanic rocks toward silicic derivatives by a combination with a temperature 100–200 °C above erupted from multiple caldera complexes of fractionation processes and assimilation “normal” asthenosphere. This should be tend to dominate the upper volcano of surrounding basement and/or roof contrasted with rifting without additional stratigraphy (Argentina-Antarctica, eastern rocks. While the emplacement of thick thermal perturbation which leads to non- Australia, Etendeka-Namibia, Scotland, mafic flows within volcanic rifted margins volcanic rifted margins (e.g., Newfound- Yemen), but in the Parana-Etendeka and has no modern analogues, a possible land, Iberia) and thermal perturbations in Ethiopia, silicic units are interbed- explanation for the mechanism of ded with the basaltic lava flows. In emplacement may be found in the the Deccan and the British Tertiary recently proposed “self-inflation” model the presence of ash layers in the for basaltic lavas (single or compound) volcano stratigraphy indicates “sili- with thicknesses ranging from 1 to 100 m cic” volcanism between periods of (e.g., Etendeka, Deccan). basalt volcanism. The switch from Underplating, or formation of an basaltic to silicic volcanism reveals over-thickened oceanic layer 3 and adja- the importance of high-level cent stretched continental crust, is evident magma chambers and crustal melt- as distinctive high-seismic velocity ing in the formation of volcanic (7.2–7.4 km/s) and associated gravity rifted margins of magma. In anomalies, but only sometimes by lower- Etendeka, individual silicic erup- crustal reflectivity. Because bright lower- tive units have thicknesses of up to crustal reflectivity can have other causes, 100 m, aerial extents >8000 km2 surface denudation should be sought as and volumes of 3000 km3, indicat- independent verification of underplating. ing large-scale explosive eruptions. Magmatic underplating may involve mul- Eruption rates in volcanic rifted tiple dike-sill systems, multiple igneous margins have not been adequately intrusions, or single magma bodies. In constrained by volume-time stud- southeast Greenland, the maximum ies of individual eruptive units igneous crustal thickness varies from 30 to and, as a first approximation, 40 km close to the thermal anomaly (i.e., track of Iceland hotspot), thinning to 18 km at 500–1000 km from the anomaly. On the northwest Australian margin, the Unroofed Loch Ba center and underplated thickness is ~7 km near the late caldera on Mull, Scotland.

8 GSA TODAY, August 2000 ocean-continent boundary. These thicknesses have been widely used to infer the 2001 Officer and Councilor Nominees magnitude of mantle temperature anomalies, but if average Vp is also measured, Council announces the following officer and councilor candidates. Biographical and used as a proxy for composition, one information on all candidates is posted at www.geosociety.org, or available by calling may also infer the degree of mantle (303) 447-2020, ext. 774, or 1-888-443-4472. upwelling. Along the Iceland hotspot track, there is a clear requirement for PRESIDENT (2001) active upwelling, defined as a mantle Sharon Mosher, Austin, Texas upwelling velocity exceeding that due VICE-PRESIDENT (2001) VVOOTTEE!! purely to the plate separation rate. In con- Tony Naldrett, Toronto, Ontario YOUR VOTE IS IMPORTANT! trast, 500 km off the hotspot track, TREASURER (2001) upwelling appears to be passive and can be Attention voting members: You should David E. Dunn, Richardson, Texas explained purely by plate velocity. On the have received a postcard in the mail Greenland–northwest Europe conjugate COUNCILOR (2001–2003), POSITION 1 with instructions on how to access our margins, crustal-generation rates as high Peter W. Lipman, Menlo Park, California secure Web site and your electronic bal- as 2000 km3/m.y. per km of margin Samuel B. Mukasa, Ann Arbor, Michigan lot. The site also posts biographical occurred at breakup, declining rapidly COUNCILOR (2001–2003), POSITION 2 information on each candidate and the over a few m.y. Magma production rates of John M. Bartley, Salt Lake City, Utah 1999 GSA Annual Report. If you have volcanic rifted margins (i.e., per kilometer Steven M. Colman, Woods Hole, Massachusetts not yet received these instructions, or if of active margin) seem similar to that of you need paper copies of the ballot and island arcs, but volcanic rifted margins are COUNCILOR (2001–2003), POSITION 3 biographical information on the candi- less effective in generating new continen- L. Peter Gromet, Providence, Rhode Island dates, please contact us at (303) 447- tal crust because the total length of active Suzanne Mahlburg Kay, Ithaca, New York 2020, ext. 774, 1-888-443-4472, or arcs exceeds that of active volcanic rifted COUNCILOR (2001–2003), POSITION 4 [email protected]. margins by a factor of 5–10. Jaime Roldan-Quintana, Hermosillo, Sonora Deadline: Ballots must be submit- Seaward-dipping reflector sequences, Gerald M. Ross, Calgary, Alberta ted electronically or postmarked first recognized along the North Atlantic by September 16. margin, are a characteristic of volcanic rifted margins and are recognized by reflectors which steepen and diverge Plumes and Upwellings: downward to dips of over 15 degrees. Magmatism and Rifting These reflector packages reach up to a the uplift/subsidence, extension/volcan- Melt production at volcanic rifted maximum estimated thickness of 10 km ism, of the lithosphere. margins requires (1) mantle potential tem- and extend for up to 200 km perpendicu- Some models of volcanic rifted mar- peratures of 1400–1600 °C (which may or lar to the margin and up to 4000 km along gin formation that involve input from the may not be expressed as geochemical or strike (e.g., Argentina-Brazil margin). Sea- mantle require that rifting and magma- geophysical anomalies), and (2) litho- ward-dipping reflector sequences are inter- tism were essentially synchronous, but in spheric thinning to (or preexisting litho- preted to be largely subaerial eruptions, many volcanic rifted margins (e.g., Yemen, spheric thickness no more than) ~90 km and their seaward termination may typi- North Atlantic, Australia), several million to allow adiabatic decompression melting. cally mark the transition to submarine years lapsed between the onset of flood Geophysical and geochemical data, backed eruptions. The sequences may be predomi- volcanism and widespread rifting. In the up by theoretical modeling, support the nantly volcanic rocks with associated sedi- Parana-Etendeka, it can be argued that the presence of one (or more) plume(s) during mentary rocks. On the Namibian margin, Etendeka magmatic province was erupted the formation of the volcanic rifted mar- models of seismic data, tested against prior to onshore rifting because the main gins of the Atlantic, the Red Sea, India- magnetic data, suggest that the seaward- volcanic units can be traced from the Seychelles, and the volcanic rifted margins dipping reflector sequences package is a Etendeka into the Parana, so there could in Antarctica. However, some controversy mixture of volcanic and sedimentary not have been major topographic depres- exists over the extent to which various rocks, and on the Norwegian volcanic sions ponding sequences. Alternatively, it geochemical parameters (e.g., helium-lead rifted margin, seismic sections have been can be argued that the transcontinental isotope ratios and trace-element parame- interpreted as documenting a transition correlation of eruptive units is possible ters) can be used to define plumes. While from subaerial to submarine volcanic because the rift topography was quickly magma geochemistry clearly indicates deposits that comprise lavas and volcani- blanketed by sheetlike eruptive units. input from mantle and crustal sources, at clastic sedimentary rocks. Underplating is While “offshore valley systems” appear to present, geochemical and geophysical data an integral part of the architecture of vol- be filled with lavas and have been inter- cannot, to everyone’s satisfaction, distin- canic rifted margins and, with the extru- preted as evidence of rifting having pre- guish between core-mantle boundary sive part of the sequences, is what may dated volcanism, later deformation and plumes and upper-mantle upwellings distinguish volcanic from nonvolcanic faulting may explain the apparent “chan- related to topography at the lithosphere- rifted margins. However, there are possible neling” of units. On the North Atlantic asthenosphere boundary beneath conti- complications in margins like Sergipe- volcanic rifted margins, basaltic volcanism nents. Overall, at the Penrose, geochemi- Alagoas, Brazil. The lack of pre- and synrift overflowed the conjugate margins, as it cal and geophysical data were found to be volcanics is a classic nonvolcanic margin did in the Deccan, and as such must be far from conclusive when it came to deci- characteristic while the thick wedges of largely synrift. In the case of the volcan- phering the presence or absence of deep- postrift seaward-dipping reflectors are a ism associated with the central Atlantic mantle plume structures. What is clear is classic volcanic margin characteristic. Ocean (200 Ma) there is geochronological that thermal anomalies exist on Earth and evidence that volcanism postdated rifting that their distribution, shape, and size appear to be variable, and their duration and genesis manifest themselves to differ- Volcanic Rifted Margins ent degrees and in nonspecific order, in continued on p. 10

GSA TODAY, August 2000 9 Volcanic Rifted Margins land, India). Studies in Antarctica indicate ment followed the onset of uplift and a continued from p. 9 that landscape evolution was very slow change in base level. Scarp retreat, plana- with a cessation to scarp retreat in the past tion surfaces, and incision by fluvial sys- by 30 m.y. in some cases, but was syn- 15 m.y. On the Yemen margin of the Red tems produced a landscape that has chronous with basin formation in others. Sea, denudation peaked in the Miocene changed little in 15 m.y. In the Deccan of during breakup, with scarp retreat deter- India, some topographic expression must Denudation = Surface mining landscape evolution since that have existed, perhaps triggered by uplift, Uplift–Rock Uplift time. because palynological data indicate the Theoretical models require 500 m–2 presence of floodplain or lacustrine envi- In many volcanic rifted margins, km of uplift prior to, or concurrent with, ronments. The western Ghat escarpment what we observe today are erosional rem- magmatism depending on proximity to is believed to have an erosional rather nants, and the degree of preservation is the plume head or stem and lithospheric than a tectonic origin, and scarp retreat is inextricably linked to climate, elevation, heating. To properly understand rock believed to be the major determinant of and the amount or rate of denudation. and/or surface uplift, constraints must be landscape with the original continental The youngest volcanic rifted margins placed on the prerift paleogeography (rela- margin ~75 km west of its present loca- (Ethiopia-Yemen) are characterized by tive to sea level) and the denudational his- tion. Thus, it appears that there may be incised 3-km-high uplifted flanks atop a tory. According to the prevolcanic sedi- spatial separation of plume head or stem broad plateau. Volcanic rifted margins mentary rock record of eastern Greenland material driving uplift and zones of melt formed at the Cretaceous-Tertiary bound- and Scotland, the southern Red Sea, and generation (thinned lithosphere) within ary are characterized by major scarp north, west, and east Australia, the pre- broad plume provinces. retreat in India and an eroded mountain breakup continental masses were close to range in Scotland. The central Atlantic sea level. However, it is apparent that Characteristics of magmatic province in the eastern United some variation existed in the North Volcanic Rifted Margins States and West Africa was reduced to a Atlantic as west Greenland is characterized feeder dike swarm during 200 m.y. of ero- The Penrose Conference participants by incised fluvial systems, east Greenland sion. Within volcanic rifted margins, concluded that the defining characteristic by a landscape close to sea level and unconformities provide important tempo- of a volcanic rifted margin (that which northwest Scotland–Faeroes by a low- ral information about denudation and the distinguishes it from a nonvolcanic mar- relief, vegetated land surface. In Yemen, a potential supply of sediments to exten- gin) is the presence of a significantly shoreline existed close to the present loca- sional basins. In some cases erosion post- greater thickness of new intrusive and tion of a mountain range (~3 km) but, dated the main magmatic episode and was extrusive igneous crust, ≥~10 km, at a judging from paleocurrent information synchronous with breakup extension (e.g., rifted margin than is formed in normal and the maturity of the prevolcanic sedi- Yemen), and in other volcanic rifted mar- oceanic crust or nonvolcanic margins. ments in Yemen, a hinterland must have gins (e.g., eastern Australia) erosion and However, as we learn more about the 3- existed in the Danakil horst, Eritrea. In sediment input (i.e., with >1.4 million dimensional crustal architecture of vol- contrast to these volcanic rifted margins, km3) into adjacent or preexisting sedimen- canic rifted margins, we should perhaps be the Drakensburg mountains (South Africa) tary basins coincided with the main mag- identifying them as magmatic at all levels, are believed to have inherited “relief” at matic episode. rather than merely as volcanic. Nonethe- the time of Gondwana breakup. While the Apatite fission track analyses and U- less, Penrose 2000 suggests that the follow- nature of the Deccan-Seychelles land sur- Th/He dating are used to quantify the timing observations are sufficiently common face prior to breakup (relative to sea level) ing and rate of denudational processes at volcanic rifted margins to be regarded is unknown, in the Parana-Etendeka it is (tectonic and erosional) as measures of as characteristic features: characterized by a large aeolian erg crustal cooling, and cosmogenic isotopes (a) Subaerial volcanic rocks reached 4–6 system. are used to date paleosurfaces (e.g., Dec- km in thickness on the continental Denudation coincides with the peak can). Fission-track dating has been applied margin prior to denudation. of extension in Yemen and eastern Aus- to many volcanic rifted margins and, (b) Magmatic underplating, evident as tralia, while in west Greenland, major whereas young, hot volcanic rifted mar- high velocities (~7.4 km/s) in the lower unconformities beneath the volcanic rocks gins (e.g., Yemen) have a relatively simple crust interpreted as new mafic igneous are associated with fluvial peneplanation cooling history, older and colder volcanic crust—the intrusive counterpart of and valley incision, indicating a period of rifted margins tend to have a more com- extrusive volcanic rocks on the conti- substantial prevolcanic uplift and denuda- plex cooling history that may be difficult nental margin or seaward-dipping tion. In Antarctica, landscape develop- to unravel (e.g., United Kingdom–Green- reflector sequence in the continent- ocean transition. (c) 70%–80% of the erupted volume was About People emplaced over a 1–2 m.y. period, with Member John W. Gibson Jr. was named president and CEO of Landmark Graphics basaltic magmas erupted from fissure Corporation, a supplier of integrated exploration and production technical and economic systems. Individual eruptive units can software designed to help petroleum companies worldwide find, produce, and manage be ~100 m thick and cover several oil and gas reservoirs. 1000 km2. (d) Silicic volcanic rocks, erupted from Member Robbie R. Gries has been elected president-elect of the Association of caldera-type complexes, can be a sig- Petroleum Geologists for the 2000–2001 term. She will serve as president of the associa- nificant part of the upper (and lower) tion for the 2001–2002 term. volcano stratigraphy of volcanic rifted Member Thomas L. Wright, a consultant in San Anselmo, California, received the margins (Ethiopia-Yemen, Parana- American Association of Petroleum Geologists’ (AAPG) Michel T. Halbouty Human Needs Etendeka, eastern Australia) with indi- Award. Wright was honored at the 85th AAPG Annual Convention in New Orleans on vidual eruptive units comprising 100s April 17. The Michel T. Halbouty Human Needs Award honors an individual for the out- to 1000s km3. standing application of geology to the benefit of human needs, recognizing scientific excellence. Volcanic Rifted Margins continued on p. 11

10 GSA TODAY, August 2000 Birdsall-Dreiss Distinguished Lecturer for 2001 Announced

Steve Ingebritsen has been selected as Steve Ingebritsen directly at (650) 329-4422, metamorphic carbon dioxide flux may be the 2001 Birdsall-Dreiss Lecturer. Ingebritsen or [email protected]. The GSA Hydrogeology sufficient to affect climate; and that there is a received a B.A. degree in geology from Car- Division pays transportation expenses; the significant capacity for diffuse degassing of leton College and M.S. and Ph.D. degrees in host institution is expected to provide for the Earth in tectonically active regions. hydrogeology from Stanford University. He lecturer’s local expenses. Liberal arts colleges has been a member of the U.S. Geological are particularly encouraged to participate. Land Subsidence in the United States Survey (USGS) since 1980 and is currently From the San Francisco Bay Delta to chief of Regional Research, Water Resources LECTURE TOPICS the Florida Everglades, and from upstate Division, Western Region. He is author, along The Permeability of the New York to Houston, illustrative case with Ward Sanford, of the textbook Ground- Continental Crust studies describe three basic mechanisms water in Geologic Processes (Cambridge Univer- by which human manipulation of ground- The variation in permeability with sity Press, 1998). water causes land subsidence: groundwater depth in the crust can be probed indirectly Ingebritsen will offer the two lectures withdrawal, dewatering and oxidation of with (1) hydrologic models that use geother- detailed below. The first describes an ongoing organic soils, and dissolution collapse of mal data as constraints, and (2) the progress study of crustal permeability done in collabo- susceptible materials. In the United States, of metamorphic reactions driven by fluid ration with Craig Manning, a metamorphic subsidence due to these mechanisms flow. These data indicate that, in orogenic petrologist with the University of California affects more than 40,000 square kilome- belts, log k = –14 –3.2 log z, where k is in at Los Angeles. The second relates to a recent ters in 45 states and causes at least $125 meters squared and z is in km. This relation USGS circular on land subsidence, done in million in annual damage. Interferometric implies that typical metamorphic fluid-flux collaboration with Devin Galloway, David Synthetic Aperture Radar (InSAR) is a pow- values are consistent with fluid pressures sig- Jones, and many others. To request a visit to erful new tool for assessing and mitigating nificantly above hydrostatic values; that the your institution during the tour, contact subsidence. ■

Volcanic Rifted Margins (g) The ocean-continent boundary is and/or base-level change is a vital part continued from p. 10 abrupt (e.g., Greenland, East Coast of of the formation of volcanic rifted the United States, Namibia). margins. (e) Rift flank uplifts atop broad plateaus (h) Magmatism and rifting in volcanic (k) Unroofing of mantle rocks is not reach up to 4 km above sea level and rifted margins are not necessarily syn- observed in volcanic rifted margins act as a source for clastic sediments in chronous. Magmatism may predate in contrast to at least some non- adjacent extensional basins. Some of rifting by several million years, may be volcanic margins (e.g., Iberia, northern this uplift is permanent as opposed to synchronous with rifting, or may post- Red Sea). time-decaying thermal uplift. A grad- date rifting. Ultimately, the degree to which we ual decrease in the elevation of these (i) Prior to formation of the volcanic search for similarities or distinctions mountains away from the rift axis is rifted margin, the continental land between different volcanic rifted margins evident in both young and/or active masses were close to sea level (Yemen, may owe as much to our personal philo- (i.e., Ethiopia, Yemen) and old and/or east Greenland, United Kingdom, sophical predilections, whether we are inactive (i.e., Greenland and Scotland) Etendeka) and displayed a variety of by nature “lumpers” or “splitters,” than volcanic rifted margins. sedimentary environments (e.g., flu- to the existence of an underpinning geo- (f) Seaward-dipping reflector sequences vial, aeolian, etc.). logical truth. appear to consist of a mixture of vol- (j) Kilometer-scale uplift prior to magma- canic rocks (lavas ± ignimbrites), vol- tism is not demonstrable on most vol- Acknowledgments caniclastic and nonvolcanic sedimen- canic rifted margins, but uplifted and This report stems from a Penrose tary rocks. rapidly denuded continental margins Conference held at the Department of are observed, indicating that uplift Geology, Royal Holloway, University of London, on March 28–29, 2000.

Conference Participants

Mohamed Al-Kadasi Ian Davison Jake Hossack Andrea Marzoli Robert Smith Abdulkarim Al-Subbary Yildirim Dilek Sarah James Ken McClay K.V. Subbarao Don Anderson Cecile Doubre Claude Jaupart Greg McHone Michael Summerfield Nicholas Arndt Cindy Ebinger Priya Javeri Leone Melluso Roger Swart Laurence Audin John Encarnacion Alistair Jeffcoate Martin Menzies Christian Tegner Dereje Ayalew Richard England Dougal Jerram Daniel Miggins Mengist Teklay Joel Baker Manuel Fernandez Garry Karner Webster Mohriak Gary Thompson Christian Berndt Paul Fitzgerald Seifu Kebede Jean-Paul Montagner Montserrat Torne Wouter Bleeker Mary Fowler Bruno Kieffer Clive Neal Robert Trumbull Scott Bryan Frederick Frey Simon Klemperer Soenke Neben Ingrid Ukstins Jean-Paul Callot Kerry Gallagher Kim Knight Andy Nyblade Mike Watkeys Joe Cartwright Laurent Geoffroy Biswaketan Kundu Sanjaya Pattanayak Nicky White James Chalmers Rhiannon George Nick Kusznir David Peate Robert White Gilles Chazot Linda Hanley Hans Christian Larsen Raphaël Pik Pierre Wiart John Chesley Chris Hawkesworth Philip Leat Teal Riley Mike Widdowson Branko Corner Lara Heister Frank Lisker Pierre Rochette Ellen Wolfenden Jenny Cripps Steve Holbrook Isabelle Manighetti Richard Single

GSA TODAY, August 2000 11 Congressional Science Fellow Rachel Sours-Page New GSA Congressional Science Fellow to Begin Term in September

Rachel Sours-Page, of Oregon State University (OSU), is the 2000–2001 GSA–USGS Congressional Science Fellow. Sours-Page grew up in the San Francisco Bay Area and graduated from The College Preparatory School in Oakland, California. She attended Harvey Mudd College and neighboring Pomona College where she received a B.S. in geology. As an undergraduate, she served as student liaison to geology department faculty and as dormitory president. During 1994 and 1995, she participated in the Keck Undergraduate Research Program and completed her senior thesis on the petrology of the Mount McLaughlin region of southwestern Oregon.

In 1995, Sours-Page enrolled in OSU’s Department of Geo- Fellows can and do directly impact public awareness of earth sciences’ Ph.D. program and worked as both a teaching and science and related issues. For an account of one fellow’s influ- research assistant. Her research focused on the use of olivine and ence, see “Science and Politics: A Personal Encounter,” on p. 13. plagioclase-hosted melt inclusions in the understanding and The fellowship places highly qualified scientists in the offices determination of mantle and crustal processes at mid-ocean of individual members of Congress and committees for a 12- to ridges. Active in OSU’s student government, Sours-Page served as 15-month appointment. While fellows explicitly do not represent both the graduate representative to the geosciences department special interests, they do play a professional role for GSA during faculty and proxy senator for the Graduate Student Senate. She their appointment by bringing issues and perspectives to the also became a founding member of the Coalition of Graduate attention of GSA headquarters staff, our members, and staff Employees, the labor union for OSU graduate employees. members from the USGS. In exchange for the opportunity to Sours-Page is interested in the interface between science and acquire experience and the chance to contribute to the formula- public policy, with emphasis on environmental issues, including tion of public policy, fellows bring to the position special knowl- sustainable living, renewable resources, and the preservation of edge, skills, and competence. Fellows report periodically to the natural habitats. As a staff member working directly with Wash- GSA membership and to the USGS on geoscience issues facing ington decision makers, she will be well positioned to help bridge Congress and on the positive roles available for all earth scientists the communication gap that often exists between scientists and in policy formulation. their legislators, while furthering her own education in science To prepare for their assignments, fellows attend a two-week policy and government issues. “I’m honored to receive the orientation conducted by the American Association for the GSA–USGS Congressional Science Fellowship and am excited by Advancement of Science. Fellowship requirements include an the opportunity to represent the geology community,” Sours- exceptional competence in some area of the earth sciences, cog- Page said. Look for perspective articles from Sours-Page in upcom- nizance of a broad range of issues outside their particular areas, ing issues of GSA Today. and a strong interest in working on a range of public policy programs. The Fellowship In alignment with GSA’s Strategic Plan, the Institute for Earth Science and the Environment administers the Con- The Congressional Science Fellowship, funded by GSA and a gressional Science Fellow program and supports our members’ grant from the U.S. Geological Survey, was established in 1986. activities and interests in public policy. For additional informa- Rachel Sours-Page, named as the 2000–2001 fellow, is the 15th tion on this program and other science and policy topics, see person to take on the challenge of applying scientific and techni- “Policy and Government Affairs” in the Public Interest section cal expertise to a wide range of public policy issues. of the GSA Web site (www.geosociety.org). ■

Call for Applications!

Looking to expand your professional horizons? ◆ Believe in serving society through science? ◆ Ready for a unique challenge? Apply for GSA’s Congressional Science Fellowship 2001–2002.

Put your expertise and experience sciences or a related field with at least To learn more about the Fellow to work helping shape science and tech- five years of professional experience. If experience, contact David Verardo, nology policy on Capitol Hill. Work you possess this professional back- 1997–1998 GSA Congressional Science directly with national and international ground, have experience in applying Fellow, at (703) 625-6105 or dverardo@ leaders. scientific knowledge to societal chal- geosociety.org. The Congressional Science Fellow lenges, and share a passion for helping For application information, check will be selected from top competitors shape the future of the geoscience pro- our Web site at www.geosociety.org/ early in 2001. Successful candidates are fession, GSA invites your application. science/csf/scifello.htm or contact GSA members who possess either a The fellowship is open to U.S. citizens or Karlon Blythe, Program Officer, GSA Ph.D. in the earth sciences or a related permanent residents of the U.S. The Headquarters, (303)-447-2020, ext. 136, field, or a Master’s degree in the earth deadline to apply is February 2, 2001. or [email protected].

12 GSA TODAY, August 2000 Internships: Science and Politics: Help Form Sound Policy A Personal Encounter Through Sound Science Ann Boylan GSA is launching a new program to help undergraduate geoscience students work as interns with their congressional representatives in Washington, D.C., and in their home How many of us are politically active? chuckle, saying, “Funny, you don’t look districts. See “Science and Politics: A Per- More important, how many of us are even like a politician.” Although most of this sonal Encounter” for a first-person account politically aware? As a geoscientist work- was in jest, I felt the negativity towards of the rewards of internship. For more infor- ing for an elected official, I know how my choice was real. I would not go so far mation, contact Ann Boylan, a caseworker in underrepresented we are in the political as to say I sensed an elitist attitude, but it the Portland, Oregon, office of U.S. Senator world. was a separatist attitude. Everywhere I Ron Wyden (D-OR), at Ann_Boylan@wyden. The journey that brought me out of turned, I was reminded that geology and senate.gov. the laboratory and into the political arena politics did not mix. Everywhere, that is, For information about programs in public involved a series of serendipitous encoun- but in my government classes. policy at GSA, please contact Cathleen May, ters with several geologists who turned out When I shared my story with the fac- (303) 447-2020, ext. 195, cmay@geosociety. to be helpful mentors. It began while I was ulty and students of the government org, or Dave Verardo, (703) 625-6105, earning a bachelor’s degree in geology department, I was warmly received and [email protected]. from the Department of Geography and felt buoyed by their enthusiasm for the Earth Science of George Mason University fact that I was a geologist interested in (GMU) in Fairfax, Virginia, located near political science. I delved deeper into the only part of an environmental issue. the U.S. Geological Survey (USGS) connections between my education, my Socioeconomic considerations play an National Center in Reston, Virginia. Like scientific experience, and my role as a sci- important role, as does the freedom many GMU geology students under the entist in our democracy. elected officials have to choose a course of guidance of Department Chair Rick Diec- Then came another encounter that action regardless of any “expert opinion.” chio, I took advantage of the opportunity helped change my attitude. In 1998, Dave In general, I see a tremendous need for sci- to gain valuable experience by working as Verardo, the 1997–1998 GSA–USGS Con- entists to be involved with decision mak- a USGS laboratory assistant. I had the gressional Science Fellow, came to GMU to ers early in the formulation of policy good fortune of working with Bill Orem, a celebrate the inaugural Earth Science Week ideas. In this way, misunderstandings of biogeochemist who engaged his student by sharing his experiences in the office of fundamental science can be minimized. assistants in every part of the research pro- U.S. Senator Ron Wyden of Oregon, the Scientists must become more active in cess. Between my education in the class- congressional sponsor of Earth Science policy. Thousands of political staff mem- room and my education in the workplace, Week. As I listened to Dave talk, I imag- bers across the country are reading and I learned a great deal about what it is to be ined myself in his position, doing the researching, trying to be a part of our a scientist. things he was doing. I was amazed by the world. We need to make an effort to be a When I filed my intent to graduate in stories of how science and policy fit part of theirs by helping them understand the spring of 1998, however, I received dis- together at some times and how different geoscience. We need to know more than appointing news. Government policies the perspectives were at others. I was who our representatives are. We need to dictated that I could not keep my job with hooked! I ran up to Dave at the end of his know where they stand on issues that are the USGS unless I was enrolled in a degree presentation and said, “You have the per- important to us. Our role as citizens does program. I was crushed! I had intended to fect job. How can I do what you do?” not end on election day. We need to stay with the project for another year, Dave laughed and invited me to visit the actively participate in our government. We then move to the West Coast with my senator’s office to discuss an internship. I need to call, write, and visit our senators husband. I loved my work at the Survey, visited and was offered an internship in and representatives—both on Capitol Hill and I did not want to start graduate school Senator Wyden’s Capitol Hill office. Dur- and in their state offices. We need to do before I was ready in order to keep my job. ing the semester, I answered constituent this with our state and local government After a panicked call to the registrar’s mail and got a feel for the breadth of representatives as well. office and a scan of my transcripts, I issues followed by a member of Congress The professional benefit I receive in signed up to complete a second bachelor’s in service to his constituents and the observing the interface of science and degree in government and international larger society. Although science and tech- public policy firsthand is incalculable. It is politics. Since many of my general elec- nology are in the mix of issues, they are an experience I urge more geoscientists to tives had been in government and the only part of the larger fabric of important pursue and be encouraged to pursue. The social sciences, I could apply my previous decisions facing Americans. office of every member of Congress is work to this program and finish it in two After graduation, my husband and I open to interns. Whether one works for a semesters. I could keep my job at the moved to Portland, Oregon, where I con- city, state, or federal elected official mat- USGS and pursue a whole new area of tinue to work for Senator Wyden. During ters little so long as one takes the opportu- study that interested me. So began my the past year in the senator’s state office, I nity to intern. In doing so, we will begin odyssey into politics. have had many opportunities to call upon to build better scientists, better citizens, I was ready for anything. Except, that my scientific background in helping con- and better policies. I am not saying that is, the negative responses I received from stituents understand environmental issues an army of undergraduate geology interns my fellow scientists. Many people told me and scientific principles. I have to admit, can change the face of science policy I was crazy to study politics. Other geology however, that in observing the workings today. But an army of politically savvy students demanded to know why I did not of politics, what impresses me most is just geoscientists can change the future of pol- select a more “useful” degree, such as biol- how much influence people with limited icy tomorrow. Every day I spend working ogy. Co-workers laughed and wanted to scientific backgrounds have on environ- in public policy is a lesson in government know why I did not simply earn a certifi- mental policy, and the tremendous effort that I will take with me throughout my cate in computer skills at a technical col- they put forth to understand the science career. It is an experience that would be lege. Even a favorite geology professor behind an issue and make informed deci- beneficial for many new scientists. ■ greeted me on campus one day with a sions. I also now realize that science is

GSA TODAY, August 2000 13 A Vision for Geomorphology and Quaternary Science Beyond 2000

Report of NSF-sponsored workshop, University of Minnesota, February 2–4, 1999 Robert S. Anderson, University of California at Santa Cruz, [email protected] Emi Ito, University of Minnesota, [email protected]

Humans have achieved the ability to about on hillslopes and in rivers, glaciers sion and the transportation of the alter the planet in significant ways and and coastlines. Over long time scales, the eroded debris across the foreland. have built in the path of some of nature’s net effect of such processes is to sculpt the • Closure with respect to fluvial most destructive processes. In most places landscape. While the study of surface pro- sediment. Careful construction of on Earth, the regolith on which terrestrial cesses is a mature field, much of the work sediment budgets constitutes one of the biota depends is only a few centimeters to has focused on individual elements of the strongest means of organizing informa- meters thick. This thin layer of dirt can landscape, with little attempt to integrate tion about the erosional and deposi- evolve chemically, and it is mobile. These among the elements. In addition, we are tional system. While perfect closure facts have squarely embedded geomor- only beginning to explore how geomor- with respect to sediment in natural phology, the study of Earth’s surface and phic processes are affected by biota. We basins is seldom achieved, proper choice the processes that shape it, and the Qua- envision a community initiative to close of the study site with closure in mind is ternary sciences, the study of the history some of the gaps in our current under- preferred. of Earth’s surface through the last two mil- standing and to focus on more integrated • Variation in fluvial transport lion years, within research on global studies. The tasks will include both field mechanism. Fluvial transport is the change. These sciences can and must act studies and modeling. The key elements dominant mechanism of mass transfer as the link between the solid Earth, the are: between the erosional and depositional biological system, and the climate system. • measurement of critical mass fluxes parts of the geomorphic system. While We propose two new initiatives for throughout a small set of carefully cho- we will therefore emphasize fluvial sys- surficial processes research at the National sen transport systems (basins) over time tems, the fact that the fluvial system Science Foundation (NSF). These will con- spans long enough to include numerous forms the bottom boundary conditions stitute bold new steps that recognize the transport events and hence long enough for hillslopes explicitly links these role these sciences should play in both to characterize the response to the full systems. near-term and longer-term understanding probability distribution of events; • Land cover. The type and amount of of the Earth system. The initiatives repre- • quantitative approach to measuring vegetation influences not only the geo- sent an unprecedented level of interaction transport processes, and casting of all morphic processes operating in a basin, and commitment to integrated research processes in a quantitative formalism but their rates. It is critical not only to within the surficial-processes community. that connects explicitly to the meteoro- be aware of the role of vegetation in the logical forcing; observed process rates, but also of the PREDICTIVE EARTH SURFACE • integrated view of the geomor- vegetation history of a study site. Vege- DYNAMICS phic system that includes all key pro- tation dynamics may well play a key cesses and hence involves the tectonics, role in setting the lags between climatic We propose a community-level effort physical geomorphology, low-tempera- events and the sedimentary response of to develop and test landscape models for ture geochemistry, groundwater hydrol- the system. We seek interactions with predicting mass fluxes and landform ogy, and ecosystem biology; the biological community in developing change at time scales ranging from indi- • cooperative effort to integrate direct both better empirical data sets and a vidual storm events to millions of years. flux measurements with time-averaged theoretical understanding of these These general models would serve both as measures of erosion and deposition in dynamics. a fundamental framework for exploration the system, as deduced from strati- Community landscape evolution of landscape evolution and as a practical graphic and geochronological studies; models should have the following charac- tool for addressing pressing environmental and teristics: problems. This proposal has two comple- • use of the field and experimental data to • While they may vary with respect to mentary initiatives: Whole Basin Dynam- constrain development of community time and spatial scales addressed, they ics and Sustainable Landscapes. A crucial landscape evolution models that should all have common conceptual element in common between these initia- could be used as general predictive elements. Effort should be made to tives is the required close cooperation tools. unify varying approaches, and to between the quantitative geomorphology Some general characteristics that field encourage modular structure so that and the Quaternary geology communities. sites should have are: improved representations of particular In addition, we suggest four distinct • Manageable scale. An extremely processes could be readily incorporated. infrastructure facilities common to and small system would not include a suf- • Ambitious integrated models that seek necessary for both initiatives. ficiently wide spectrum of processes to to include biological, chemical, and promote or to encourage generalization, physical processes. Whole Basin Dynamics: while a continental scale system is likely • A commitment on the part of the sur- A Community Initiative in to be too diverse and unwieldy. face-processes community to work on Surficial Processes • Active tectonics. Some field sites standardized interfaces and program- Landscapes are inherently dynamic. should be in areas with active tectonic ming protocols for computer modeling. This dynamism reflects the combination uplift and subsidence. Such sites would • Both field and experimental studies are of tectonic processes that move rock with allow exploration of the time scales over required to constrain the proper physics respect to base level, and a suite of physi- which mountain erosion achieves rough cal and chemical surficial processes that balance with uplift, if ever. The linkages alter the state of the rock and move it must be forged between mountain ero- Vision continued on p. 15

14 GSA TODAY, August 2000 Vision continued from p. 14 fields that serve as the stage for the The standard chronological tool, near-term geomorphic play. accelerator mass spectrometry (AMS) 14C • Landscape forecasting. Event-based dates, needs calibration because 14C ages and chemistry, and to determine empiri- predictions of runoff and erosion that vary by 3000 years or more from calendar cal constants relevant to the system. can lead to the prediction of the sites of dates. While correlation with den- initiation and the paths of landslides, drochronology and U-series chronology Sustainable Landscapes: and the extent of inundation by water has made the calibration to calendar ages Landscapes at the Human Time and debris in floods. fairly reliable back to the Last Glacial Max- Scale • Landscape prediction. Decadal- to imum (18 ka), this effort must be contin- This initiative is motivated by the century-scale prediction of the land- ued. We are not at present capable of test- need to develop the science to restore and scape processes and functions under ing synchroneity of events in terrestrial protect landscape functions in order to various land-use and global climate records beyond the Last Glacial Maxi- sustain natural resource use and ecosystem change scenarios. mum. This requires that sites with date- functionality. We lack, however, both the We propose a “2050 project” to pre- able records be identified at geographically theoretical framework and the field data dict major landscape changes that would widespread locations. Demand for AMS to predict landscape change on human occur in the face of the expected changes dates far exceeds the capacity. time scales. With this initiative we attempt in the greenhouse gas content of the Many landscape events cannot be to encourage a communitywide focus on atmosphere. This exercise requires collabo- dated by 14C. Cosmogenic isotopes such as building theoretical tools, obtaining fun- ration with the general circulation model 10Be, 26Al, 36Cl, and 3He have revolution- damental field data, and communicating and hydrological communities, policy ized our understanding of geomorphic advances, in both our conceptual under- experts and planners, and ecosystem biol- processes and climatic timing in both standing of the system and in the tech- ogists. An added collaborative opportunity high-altitude and arid landscapes. U-series nologies to monitor it, to practitioners. A with industries such as hydroelectric dating has reenergized the study of past strong educational component to the ini- power and insurance companies should be sea-level changes, and has provided tiative recognizes that land use and explored. chronological control to the study of ecosystem function issues have wide uplift of tectonically active coastal areas. appeal to students; we will strive to pro- INFRASTRUCTURAL SUPPORT Methods such as thermal luminescence vide them opportunities to participate in and optically stimulated luminescence are both the development of theory and its Chronologies, Database, and now providing ages of flood and loess application to human-scale issues. The Sample Curation deposits. Fission-track counting has Sustainable Landscapes program has three Chronology is fundamental to proven useful in studies of long-term components. understanding both the rates of change exhumation. However, the laboratories • Reference landscape. We need full, and the correlation of events separated high-resolution characterization of the geographically. topographic and subsurface bedrock Vision continued on p. 16

GSA TODAY, August 2000 15 Toward a Stewardship of the Global Commons Engaging “My Neighbor” in the Issue of Sustainability Part VIII: We Are a Part of, Not Apart From, the Global Ecosystem

A.R. Palmer, Institute for Cambrian Studies, Boulder, Colorado

“Humans aren’t the only species on Earth; they One of the tragic and unintended consequences of the expo- just act like it.” nential increase (see Part III, GSA Today, v. 10, no. 3) in urbaniza- —Unknown tion, particularly in the past century, has been the increasing iso- lation of human beings from the natural rhythms and conditions that both nurture and constrain them. This is especially true in Prior to the agricultural revolution (about 10,000 years ago), the so-called developed world, where, aided by the ease and humans had lived off the land for perhaps hundreds of millen- rapidity of transport of goods, our city markets have fresh vegeta- nia. Survival depended on knowledge of local ecosystems for bles, fruits, milk, and meat more or less continuously available. hunting, food gathering, medical assistance, and shelter. The pas- We have very little understanding of the unique combinations of sage of time was measured by natural seasonal cycles; the rhythm soil, water, weather and climate that determine the seasons of of life was the rhythm of the seasons. We were an integral and harvest for the fruits and vegetables we enjoy directly, or of the integrated part of the global ecosystem. processes which make it possible to bring meat and milk to our With the invention of agriculture and accompanying tech- tables. We have even less of an understanding of the complex nological innovations, villages and finally cities developed, arti- interaction among elements of the lithosphere, hydrosphere, and sans appeared, and social structures and communications became atmosphere that sustain populations of fish in our oceans and more elaborate. Exploitation of natural resources for enrichment lakes. of the human enterprise became a part of the more urbanized Many of us are far removed from our heritage as peoples of cultures. There seemed to be no limits to those resources. The the land. As a consequence, we are dependent on specialized creative human mind and the advent of commerce found technology, skilled artisans, global commerce, and large-scale increasingly more sophisticated ways to obtain the resources and exploitation of the commons (see Part I, GSA Today, v. 10, no. 1) to use them. Thus, today, although we are still integral parts of for food, shelter, and clothing. Most of us have lost the knowl- the system, we are less integrated. We are somewhat analogous to edge needed to do even simple farming. That loss may come back an exotic species that disrupts the ecosystems into which it is to haunt us because large cities are the most vulnerable human introduced.

on which all surface processes occur. Vision continued from p. 15 Within the past decade, laser altimetry has come into its own as a tool for generating engaged in these dating schemes are lim- high-resolution digital elevation models at ited, and the wait for dates can be long. 2 m resolution. It is at this scale that many The need for global databases is geomorphic processes act, as they can be becoming critical in many disciplines. strongly controlled by local gradients and Databases serve a variety of functions. local curvature of the landscape. A recent Beyond making data available, they pro- example of the utility of laser altimetry is vide a protocol for data collection such as in the mapping of shoreline change in the inclusion of the original lab analysis to central California during the 1997–1998 enable, for example, chronological correla- El Niño. tion of records dated by 14C at different We propose that the NSF support a times. Selected samples and relevant data facility for the collection of 2-m-resolution should be archived in a publicly accessible digital elevation models. At present, facility. For certain types of samples, such remote sensing is expensive in terms of as sediment cores and speleothems, cura- hardware, software, and training. Few tion facilities similar to those for Ocean facilities exist with the luxury of full-time, Drilling Program cores can serve this func- long-lived support of personnel to aid in tion. The first such facility is taking shape the training of new users and to ensure at the University of Minnesota. continuity of the program. High-Resolution Digital Shared or Centrally Managed Topographic Mapping Resources Field Equipment Topography is the fundamental data Maintaining large stores of equip- set that serves as the test of a theory of ment is expensive. Such equipment landscape evolution and as the template includes deep-drilling equipment, and

16 GSA TODAY, August 2000 habitats in a sustainable future. We—or our families—may have to learn again how to plant, nurture, harvest, and hunt. We may have to relearn how to live with the seasons and in balance with Geoscience Day Scheduled our surroundings. The geological sciences have taught us that we live in a uni- for Reno Meeting verse of change. This lesson is embodied in a beautiful paraphrase of a verse from the Qur’an (Sura 27; Aya 88): “In the presence of eternity, the mountains are as transient as the clouds.” Geologic Geoscience Day, a field trip for students from a studies of the environmental record since the last deglaciation middle school with a large proportion of minority (about 13,000 years ago) show that this change includes global students, will be held Wednesday, November 15, ecosystems (e.g., Ruddiman and Wright, 1987). Nature is quite during the GSA Annual Meeting in Reno. This dynamic and interactive. We need to understand that the com- program, sponsored by the GSA Committee on plex of systems that makes up our present-day environment has Minorities and Women, began at the 1976 meeting never been steady state. in Denver, Colorado, when Lou Pakiser of the U.S. Increasingly sophisticated biological studies demonstrate Geological Survey lead the trip. At nearly every that all organisms share some common elements, if only at the annual meeting since, geologists, many of them from genetic level. Although we humans seem to feel and act as if we minorities, have joined students and their teachers are distinct from all other organisms in the web of life, this is not on day-long explorations of the geology of the host really the case. If we look back in geologic time (see Part II, GSA city. Thousands of youngsters have learned about Today, v. 10, no. 2), our self-determined uniqueness within the web blurs. This blur involves not only our biological relationships geology and have had the opportunity to meet and to other organisms, but also the cultural development of our interact with minority scientists. For many students, human species. We are truly a fundamental part of the global this has been their first exposure to geology and ecosystem. often the first time they have met a minority Once we come to terms with the imbalance we have created scientist. in the global ecosystem by failing to remember that our context Donations to support Geoscience Day can be is within that ecosystem, we can face the challenges of sustainability creatively. sent to the GSA Foundation. If you are interested in participating in the program or otherwise supporting REFERENCE CITED activities of the Committee on Minorities and Women, please contact Mary Dowse, Chairman, GSA Ruddiman, W.F., and Wright, H.E., Jr., eds., 1987, North America and adjacent oceans during the last deglaciation: Boulder, Colorado, Geological Society of Committee on Minorities and Women, Department America, The Geology of North America, v. K-3, 501 p. ■ of Natural Sciences, Western New Mexico University, Silver City, NM 88062, [email protected].

various surveying and monitoring equip- We expect many spin-off experimental The initiatives we propose have major ment. A centralized facility, if properly studies from the proposed initiatives. implications for civil and environmental managed, would assist the scientists, and engineering. What we learn from these be cost effective for the NSF. This arrange- EDUCATION AND OUTREACH initiatives will be shared in a series of ment is similar to the Incorporated workshops and short courses offered at Geomorphology and Quaternary Research Institutions for Seismology, or professional meetings. sciences are among the most accessible of IRIS, program in seismology, University the geosciences. The recent spate of catas- NAVSTAR Consortium, or UNAVCO, in ACKNOWLEDGMENTS trophic events and unusual weather pat- Global Positioning System studies, PICO terns has brought the topic of global This workshop, funded by the (now VECO) for polar and arctic support, change to the forefront of the public’s National Science Foundation’s Division of or Drilling, Observation, and Sampling of consciousness. We must educate the pub- Earth Sciences (NSF-EAR) Geology and Earth’s Continental Crust (DOSECC), Inc., lic about the likely response to global Paleontology Program, was held at the in deep continental drilling. changes, with the twin perspectives of the University of Minnesota in February 1999. response to past climates, and of process- The authors organized the workshop, National Laboratories for based theoretical research. whose participants were Allan Ashworth, Experimental Surface Process We see several levels and numerous Thure Cerling, Peter Clark, Bill Dietrich, Dynamics formats for bringing geomorphology and Russ Graham, Eric Grimm, Vance Holli- At present, only a few major experi- the Quaternary sciences to the public. day, Jim Knox, Jack Oviatt, Chris Paola, mental facilities for the study of earth sur- Effective visualizations can bring the geo- and Liz Safran. ■ face processes exist. These labs are expen- morphic processes to colleges. Working sive to maintain. It is important that these with K–12 educators, these visualization facilities are maintained and are accessible efforts can be repackaged for elementary to the entire community on a competitive and secondary school students. Geomor- basis. We propose a small funding pro- phic processes can also be brought to the gram that would facilitate the kind of general public via numerous science and open door policy that St. Anthony Falls natural history museums. Hydraulic Laboratory has implemented.

GSA TODAY, August 2000 17 Diana Stordeur to Be GSA’s First Distinguished High School Earth Science Educator in Residence

Ann Cairns, Director of Communications and Marketing

K–12 earth science teachers will soon have a new advocate at best possible start, GSA. Diana Stordeur, science coordinator at Eaglecrest High we want to work School in Aurora, Colorado, has been selected as the inaugural with a local educa- Distinguished Earth Science Educator at GSA. Stordeur will take a tor from a school leave from her position in the Cherry Creek School District, rec- district with a ognized for its excellence in science education, to work full time national reputation at GSA headquarters in Boulder during the 2000–2001 academic for excellence in sci- year. Subaru of America, Inc., a corporate sponsor, funds this new ence education.” program. Robert Ridky, Working with Science, Education, and Outreach staff mem- chair of GSA’s Edu- bers, GSA’s Education Committee, and other members, Stordeur cation Task Force, is will help design our efforts to serve the K–12 geoscience educa- pleased to have Diana Stordeur tion community, providing a much needed user perspective. Stordeur on board. Stordeur will also facilitate design of the GSA Web site for educa- “The recent report tors. It will serve as an information clearinghouse for teachers, of our task force directing them to a wide variety of resources—geoscience infor- identifies the development of teacher certification tracks within mation, products for classroom use, and other services—on the geoscience programs as a primary objective,” he said. “Establish- Web. ing discipline-based teacher education programs is also a national “We have needed this kind of participation from the K–12 goal, one that is fully endorsed by the National Academy of Sci- earth science education community for a long time,” CEO Sara ences and heavily supported by the National Science Foundation. Foland said. “We want to make certain that GSA’s efforts and Diana’s background and experience makes her uniquely qualified resources go into activities and programs that match the priorities to contribute to this important initiative.” of earth science teachers. In order to get the program off to the Making a Difference Stordeur holds a B.S. in geology from the State University of New York, Stony Brook, and an M.A. in secondary science education from Columbia University. Affiliated with Colorado’s Cherry Creek School District since 1989, she has taught earth sciences, biology, advanced-placement biology, general science, and chemistry. Stordeur is enthusiastic about bringing the classroom per- NEW spective into GSA, and sees this year as an opportunity to make a Geology Terms difference. “Consolidation and visibility of earth science resources in the GSA Bookstore!in English and Spanish for teachers are desperately needed,” she said. “I’m also looking forward to acting as a bridge between such a venerable organiza- Terminología Geológica tion as GSA and earth science teachers around the country.” en Español e Inglés Looking Ahead by Henry Aurand Upon completion of her year at GSA, Stordeur will return to her school district and share what she has learned about available 118 pages Whether you are an armchair geologist or a seasoned profes- earth science education resources. She will be able to mentor her 3-5/8"x5" peers by conducting science academies for other educators at all sional, this pocket guide is a Softcover levels in the district. She will also work to integrate the national handy reference for describing standards for earth science education into the district’s curricu- Perfect bound a geological vocabulary in lum development process in response to new State of Colorado ISBN: 9-932653-29-4 Spanish and English. Filled with proficiency standards. The Earth Science Educator program is part of GSA’s long- Nonmember price: useful tables, charts, and over $7.95 standing commitment to support of earth science education. It 2,400 terms, this book is sure to will be ongoing, thanks to the generous support of Subaru of Member price: become a well-thumbed resource. America. ■ $6.36 A Sunbelt Pocket Guide

Order at the GSA Bookstore www.geosociety.org Brought to you through the generosity of Subaru of America, Inc. Toll-free 1-888-443-4472 Fax 303-443-1510

18 GSA TODAY, August 2000 GSA Names 2000 Medal and Award Recipients

Society awards for 2000 will be presented to the following people at the GSA Annual Meeting in Reno in November.

PENROSE MEDAL GSA PUBLIC SERVICE AWARD O.E. MEINZER AWARD (HYDROGEOLOGY DIVISION) Robert L. Folk Orrin H. Pilkey University of Texas at Austin Duke University Francis H. Chapelle U.S. Geological Survey, South Carolina DAY MEDAL RIP RAPP ARCHAEOLOGICAL Robert Stephen John Sparks GEOLOGY AWARD G.K. GILBERT AWARD Montserrat Volcano Observatory Richard L. Hay (PLANETARY GEOLOGY DIVISION) Tucson, Arizona Laurence Soderblom DONATH MEDAL U.S. Geological Survey, Flagstaff (YOUNG SCIENTIST AWARD) GILBERT H. CADY AWARD Basil Tikoff (COAL GEOLOGY DIVISION) KIRK BRYAN AWARD University of Wisconsin—Madison Russell D. Dutcher (QUATERNARY GEOLOGY AND Carbondale, Illinois GEOMORPHOLOGY DIVISION) NEW HONORARY FELLOW Brian F. Atwater Gerhard Einsele E.B. BURWELL, JR., AWARD University of Washington Geologisch-Paläontologisches Institut (ENGINEERING GEOLOGY DIVISION) der Universität Tübingen James P. McCalpin LAURENCE L. SLOSS AWARD FOR GEO-HAZ Consultants SEDIMENTARY GEOLOGY GSA DISTINGUISHED (SEDIMENTARY GEOLOGY DIVISION) SERVICE AWARD GEORGE P. W OOLLARD AWARD George D. Klein Suzanne Mahlburg Kay (GEOPHYSICS DIVISION) SED-STRAT Geoscience Consultants, Inc. Cornell University Donald W. Forsyth Brown University STRUCTURAL GEOLOGY AND Lee R. Kump TECTONICS DIVISION CAREER Pennsylvania State University HISTORY OF GEOLOGY AWARD CONTRIBUTION AWARD Bruce F. Molnia Hugh S. Torrens S. Warren Carey U.S. Geological Survey, Reston Keele University Sandy Bay, Australia

For mailing addresses, call GSA at 1-888-443-4472. Coming soon!

SPE343 Tectonics of the Coast Mountains, Southeastern Alaska and British Columbia Edited by Harold H. Stowell and William C. McClelland

SPE345 Volcanic Hazards and Disasters in Human Antiquity Edited by Floyd W. McCoy and Grant Heiken

SPE346 Ancient Lake Creede: Its Volcano-Tectonic Setting, History of Sedimentation, and GSA Publications Relation to Mineralization in the Creede Mining District P.O. Box 9140 Edited by Philip M. Bethke Boulder, CO 80301-9140 and Richard L. Hay Toll-free: 1-888-443-4472 Fax: 303-443-1510 Web: www.geosociety.org

GSA TODAY, August 2000 19 FIELD FORUM REPORT Glaciohydraulic Supercooling, Basal Freeze-on, Stratified Basal Ice and “Deformable Till Beds”: Matanuska Glacier, Alaska

Conveners: Edward B. Evenson, Earth and Environmental Sciences, Lehigh University, Bethlehem, PA 18015 Daniel E. Lawson, Cold Regions Research and Engineering Laboratory, Hanover, NH 03755 Grahame J. Larson, Geological Sciences, Michigan State University, East Lansing, MI 48824 Richard B. Alley, Geosciences, Pennsylvania State University, State College, PA 16802

Geoscientists have long known that by ice marginal uplift, sublimation, and inated, basal freeze-on ice and the frozen- the best insights come at outcrops and wind etching, allowed an international on subglacial deforming bed. exposures. The GSA Field Forum is a new group of glacial geologists, geomorpholo- In three days of study, participants approach that combines the traditional gists, sedimentologists, geophysicists, geo- tested the evidence and implications of observations of a field trip with the tar- chemists and glaciologists to simultane- glacier growth on the bottom. A demon- geted scientific discussions of a Penrose or ously examine, discuss, photograph, and stration of sampling protocols involving a Chapman Conference to advance the sample the basal and subglacial facies of cement saw produced new samples. Gra- understanding of a particular topic across the large, active, and well studied hame Larson has used these to confirm an important segment of the community. Matanuska Glacier. earlier work showing bomb-produced tri- Recent debates concerning the nature and Participants traveled to the tium in basal ice underlying tritium-free importance of deformable beds, ice-bed Matanuska Glacier with six stops along older glacier ice, demonstrating the recent interactions, and glaciohydraulic super- the Matanuska Valley to photograph and origin of the underplated material. Associ- cooling and its role in debris entrainment discuss the modern Matanuska outwash ated samples have been analyzed by par- and transport made a field forum focused system and deglacial features of the Knik- ticipant Thure Cerling for their gas (3He) on subglacial processes timely, especially Matanuska glacial system. A hike to the composition, and large anomalies from with respect to the flow and dynamics of glacier margin allowed participants to atmospheric concentrations attest to the former ice sheets. Altered basal conditions familiarize themselves with the ice- complex processes occurring during and can cause hundredfold or larger changes marginal conditions and plan appropri- after ice accretion. The clear evidence of in ice-flow speed, and paleoclimatic ately for the next three days at the ice metamorphic processes in some, but not records show that such changes have margin. all, basal ice generated vigorous discussion occurred in the past. Basal conditions also Previous work at the Matanuska on the relative importance of accretional play a critical role in debris entrainment Glacier has shown that during the sum- processes and postaccretion modification and transport. In particular, debris fluxes mer melt season, pressurized subglacial in generating the observed layering. Every- associated with Heinrich events and till waters flowing from overdeepenings one agreed that we are still confused, but transport and deposition emphasize the supercool and grow ice on the glacier’s at a much higher level! Staci Ensminger importance of understanding processes base, trapping debris (mainly silt) and summarized her results showing that occurring at the glacier bed. Many impor- forming laminated basal-ice sections sev- debris bands crosscutting the body of the tant questions regarding the origin, defor- eral meters thick. Ice flow during the win- glacier are basal crevasses charged by silt- mation, and evolution of basal ice and ter is not balanced by the slow sublima- laden basal waters, and several partici- subglacial sediment still remain unan- tion, so the ice margin upthrusts to pants related consistent observations from swered and require a multidisciplinary produce superb exposures of both the lam- other glaciers. approach by earth scientists with diverse backgrounds. The recent recognition that onset of glaciation can increase erosion rates by 1–2 orders of magnitude has further focused attention on glacier-bed processes because of the clear need to include glaciers in the models of mountain belts and global biogeochemical cycling. Finally, it is only by reviewing field evidence, data, and models of basal processes of modern glaciers that we can hope to understand the erosional, depositional, and landform record of former ice sheets and predict the behavior of modern glaciers and the Greenland and Antarctic ice sheets. The first GSA Field Forum convened in Alaska, March 18–22, 2000. The logistics of winter field work (temperatures of –40 °F are common this time of the year at the Matanuska Glacier) and severe lodging limitations required restricting participation to 27 people, including the leaders. Spectacular weather, combined with the excellent winter exposures produced Richard Alley and Geoff Boulton examine attenuated folds in basal stratified facies.

20 GSA TODAY, August 2000 COLORADO SCHOOL OF MINES DEPARTMENT HEAD - GEOLOGY AND GEOLOGICAL ENGINEERING The Colorado School of Mines (CSM) solicits neering. Programs are enhanced through collaboration with other applications for the position of Head, departments including Geophysics, Chemistry and Geochemistry, Department of Geology and Geological Petroleum Engineering, Mining Engineering and Environmental Engineering. This position offers the unique opportunity to Sciences and Engineering. work in an applied, interdisciplinary environment. Applicants must The Department Head is responsible for management of department have a Ph.D. in geology, geological engineering or other geoscience affairs for approximately 18 faculty, 3-5 staff, 75 undergraduate stu- field. Pertinent management, teaching and research skills are dents and 118 graduate students. Responsibilities include teaching, desired. A minimum of ten years of a combination of academic and direction of graduate research, the advancement of education and industrial and/or government experience in both basic and applied research programs, faculty and staff development, resource acquisi- geoscience and/or geological engineering is required. The successful tion and industry liaison. Information about the school and the candidate will work with other department heads on campus to lead department can be found at http://www.mines.edu, and development of innovative, multi-disciplinary education and http://www.mines.edu/Academic/geology. research programs in earth science and engineering. Applicants should send a letter of application, resume, brief state- The Department has a strong tradition in applied undergraduate and ment of immediate professional goals, and names and addresses of graduate education and offers a B.S. (Geological Engineering) three professional references should be sent to: degree with subdisciplines of engineering geology and geotechnics, Colorado School of Mines groundwater engineering, environment, petroleum and mineral Office of Human Resources exploration and M.S. (Geology, Geochemistry), M.E. (Geological Search #00-051010 Engineering) and Ph.D. (Geology, Geological Engineering, 1500 Illinois Street Geochemistry) degrees. Education and research programs empha- Golden, CO 80401 size a field, laboratory and theoretical balance in the integration of basic and applied geoscience and engineering. Programs of study Review of applications will begin October include all of the basic geosciences, particularly as applied to energy 1, 2000, and continue until such time as a and mineral deposit geology and exploration, hydrogeology and successful applicant is chosen. groundwater engineering, geotechnical engineering, engineering CSM is an EEO/AA employer. Minorities geology and geological aspects of environmental science and engi- and females are encouraged to apply.

The late-winter sun triggered debris ice visited earlier. Many participants took Inn, Anchorage), Jodi Talcott and staff flows from basal ice and seasonally frozen- advantage of the spectacular weather and (Majestic Valley Wilderness Lodge), and on subglacial till, and observations of the the two available Super Cubs to fly up the Bill and Kelly Stevenson (Glacier Park). flows illustrated the linkage between basal Matanuska and into College Fjord in The Cold Regions Research and Engineer- ice and morainal deposits. Comparison of Prince William Sound, and several made ing Laboratory cosponsored the forum. the nascent deposits to the prominent Lit- ski landings in the Matanuska snowfields. The National Science Foundation funded tle Ice Age moraine and other sediment Other participants switched to structural the participation of students and key accumulations clearly showed the geomor- geology and concentrated on the beauti- invited participants. Jeff Strasser and Staci phic importance of the active processes. fully exposed thrust features of the ice Ensminger wrote the guidebook and pro- Talks by the convenors and field trip margin. vided invaluable logistical and scientific guide editors Jeff Strasser and Staci Ens- support, and Jay Fleisher provided the minger linked the wintertime observations Acknowledgments photograph included in this report. ■ to summertime processes and to a wealth We thank Laura Cambiotti (Lehigh of other data collected over decades of University), Tony Carter (Copper Whale work on the glacier. The talks also empha- sized the physical basis for expecting that supercooling beneath overdeepened Forum Participants glaciers is a widespread process, with implications for glacier erosion, sedimen- Richard Alley John Gosse tation, and motion. Talks contributed by John Anderson Bernard Hallet Matt Roberts and Jay Fleisher then Greg Baker Ardith Hansel demonstrated features from Iceland and Derek Booth Alan Knueble coastal Alaska quite similar to those of the Geoff Boulton Grahame Larson Matanuska Glacier, while John Anderson Thure Cerling Dan Lawson showed tantalizing records from the Jim Cotter Tom Lowell Antarctic continental shelf at least suggest- Kurt Cuffey Dave Mickelson ing the possibility of related processes Jane Dionne Peter Moore there. Don Easterbrook Carrie Patterson On Thursday, participants were given Staci Ensminger Matthew Roberts the morning and snowmobile transporta- Ed Evenson Jeff Strasser tion to visit and sample exposures of basal Jay Fleisher Slawek Tulaczyk Dru Germanoski

GSA TODAY, August 2000 21 PENROSE CONFERENCE SCHEDULED Longevity and Dynamics of Rhyolitic Magma Systems Penrose June 7–12, 2001 CONFERENCE Mammoth, California Application due date: January 1, 2001

Conveners: Kurt Knesel, Department of Earth Sciences, University of Queensland, St. Lucia, Brisbane, Qld 4072, Australia, 61-7-33659779, fax 61-7-33651277, [email protected] George Bergantz, Department of Geological Sciences, Office Box 351310, University of Washington, Seattle, WA 98195-1310, USA, (206) 685-4972, fax 206-543-3836, [email protected] Jon Davidson, Department of Earth and Space Sciences, University of California, Los Angeles, CA 90095-1567, (310) 206-3042, fax 310-825-2779, [email protected] Web site: www.geology.washington.edu/bergantz/penrose-2001.htm

Mammoth Mountain forms the southwest rim of the Long growth- and dissolution-zoning reflect protracted fractiona- Valley caldera, one of three large Quaternary rhyolitic caldera tion of a single magma body or remobilization and dispersal centers in the United States. Long Valley, a site of recent volcanic of crystal mush during injection of fresh magma into the sub- unrest, lies at the heart of current debate over the mechanisms volcanic system? How do crystals move in the magma system, and time scales for the production, storage, and differentiation of or, are the crystals effectively static in a moving magma rhyolite magma. Such information is critical to our understand- system? ing of fundamental geologic problems such as the formation and • What is the efficacy of, and what are the driving forces for, growth of Earth’s continents and predicting volcanic hazards. convection and/or mixing in silicic magmas? Can crystal dise- The conference aims to bring together petrologists, geo- quilibrium features, such as chemical and/or isotopic zoning chemists, volcanologists, and geophysicists actively studying the and dissolution surfaces, serve to discriminate between ther- generation and evolution of silicic magmas. We hope to resolve— mal convection and magma mixing? or at least constrain—a number of very important and currently • What are the time scales needed to produce large, rhyolitic highly topical issues pertaining to the shallow-crustal evolution magma bodies? Recent work using 40Ar/39Ar, Rb/Sr, or U-series of large, typically caldera-forming, silicic magma bodies. Issues isotope data has led to the suggestion that rhyolite magmas in include: the Long Valley system are stored, following differentiation, for long (105–106) time scales. This contention has been dis- • What is a magma chamber—a large, long-lived fractionating puted principally on the basis that it would be difficult to liquid body or a “sleepy” crystal mush that gets kicked to life keep a body of magma thermally viable for such long periods, every so often, remobilizing existing material? To what degree even if >500 km3 volume. Alternative physical models have do plutons carry forward, in some integrated way, the expres- been proposed, such as remobilization of juvenile plutons or sion of this? cumulate materials and ion microprobe work on zircons has • What do crystals really represent—phenocrysts vs. xeno- variously upheld or contested the claims for long magma resi- crysts—and what “memory” do they retain? Does crystal dence times. A key focus of the meeting will be to evaluate the different types of data available that bear on ages of magmatic events, and discuss their interpretations. GSA Needs Keynote talks will outline the current state of knowledge Professional Representatives! concerning the generation and evolution of large rhyolitic magma systems and will set the foundation for evaluation of We’re looking for applied geoscientists to participate as GSA existing paradigms, development of new models, and discussion Professional Representatives. This network of volunteers helps GSA of future research directions. Most of the meeting will focus on improve its service to professional geoscientists and further diversify poster sessions and group discussions. Mid-meeting field trips to its growing membership. selected Bishop Tuff and Sierran plutonic locations will serve to As a Professional Representative, you’ll act as an ambassador for GSA, raise questions concerning limits and constraints on sampling spreading the word among your colleagues about the benefits of and interpreting geochemical data from pyroclastic deposits GSA membership, such as: based on our knowledge of how large silicic systems erupt, links ❖ between plutonic and volcanic environments, and the impor- national and regional meetings that give professionals a chance tance of recharge and mixing in magma evolution. to network with others in their fields, meet researchers working The conference is limited to approximately 50 participants to on issues of mutual interest, and explore interests outside their specialties; ensure a workshop atmosphere focussed on manageable discussions. We encourage participation of graduate students working ❖ student mentor programs, such as the Roy J. Shlemon Mentor on silicic magma systems; partial student subsidies will be avail- Program in Applied Geology and the John F. Mann Mentor able. The registration fee, which will include lodging, some Program in Applied Hydrogeology, for professionals who have meals, field trips, and all other conference costs except personal knowledge and experience to share; and incidentals, is not expected to exceed $750. Information on travel ❖ our employment service, which brings job seekers and employers to the conference will be provided in the letter of invitation. together year round, and provides interview opportunities and Application deadline: January 1, 2000. E-mail your applica- panel discussions at our Annual Meeting. tion to Kurt Knesel ([email protected]). Include a state- For more information, or to sign up to be a Professional ment of your experience and interests as related to the themes of Representative, contact Joanna Conley at [email protected], the conference and a proposed poster presentation title. We (303) 447-2020, ext. 107, or 1-800-472-1988, ext. 107. encourage you to include a statement of what you perceive to be the most critical questions. ■

22 GSA TODAY, August 2000 Geoarchives and the Preservation of THE PALEONTOLOGICAL SOCIETY DISTINGUISHED LECTURER PROGRAM Archival Materials 2000-2003 The International Union of History very year the Paleontological Society and Philosophy of Science (Division of History of Science) is interested in the selects outstanding scientists whose preservation of archives relating to 20th works are on a wide variety of (and now 21st) century scientific E achievements, which outnumber those paleontological topics for The of all previous centuries put together. Paleontological Society Distinguished Under the chairmanship of R.W. Home Lecturer Program. Each Distinguished of Melbourne University, its Commis- sion on Bibliography and Documenta- Lecturer has national and international tion is therefore undertaking a world stature in paleontology, has traveled program that aims to make the scientific community aware of the importance of widely, and has published extensively. preserving contemporary scientific This program is intended to make available lecturers for inclusion archives. in departmental speaker series or other college and university With help from the International Commission on the History of Geologi- forums. cal Sciences, information about the loca- The Paleontological Society Distinguished Lecturers for the tion of geology-related archives on notable geologists and of geological 2000-2003 academic years are included below with their e-mail organizations and institutions world- contacts. Additional information, including titles, is available on wide is being collected. Other types of The Paleontological Society homepage at http://www.uic.edu/ information being collected includes: • locations of significant geoarchives; orgs/paleo/speakerseries.html. If your department is interested • names and addresses of archivists; in inviting one or more Distinguished Lecturer to your institution, • names and addresses of key organizations involved in Earth Heritage please contact them directly. Although financial arrangements Conservation; must be made directly with each speaker, all Distinguished • techniques being used to preserve Speakers have agreed to be available on an expenses- archival materials; • details about (or plans for creating) only basis. If you have any questions catalogs and books listing geoarchives. regarding this program, please feel free to Send information to: contact William I. Ausich at [email protected]. K.S. Murty 101 Sneh Chaya Apts. Roger J. Cuffey – Bryozoans and Reefs 28 Hindustan Colony e-mail: [email protected] Amaravati Road Steven J. Hageman – Species; Carbonates Nagpur 440 010, India e-mail: [email protected] 91-712-557-984 David M. Harwood – Plankton; Antarctica fax 91-712-549-521 e-mail: [email protected] [email protected] Steven M. Holland – Stratigraphy; Stability e-mail: [email protected] Brian T. Huber – Cretaceous Deep-Sea Record e-mail: Huber. [email protected] Claudia C. Johnson – Paleoenvironments ADS GET e-mail: [email protected] RESULTS Bruce S. Lieberman – Evolution; Cambrian e-mail: [email protected] Charles R. Marshall – Innovation and Incompleteness e-mail: [email protected] CONTACT David L. Meyer – Crinoids and Edrioasteroids GSA Today Advertising e-mail: [email protected] Lisa E. Park – Ostracodes and Paleoclimate P.O. Box 9140, Boulder, CO 80301 e-mail: [email protected] Judith Totman Parrish – Paleoclimates 303-447-2020 x153 • 1-888-443-4472 e-mail: [email protected] [email protected] Bruce Runnegar – Metazoan Origins: Carbonate Isotopes e-mail: [email protected] Charles E. Savrda – Trace Fossils e-mail: [email protected]

GSA TODAY, August 2000 23 Planned Giving Options Give Donors the Ability to Give Generously Today and in the Future

Julie A. Wetterholt, Director of Development

During the past three years, GSA limits. The higher your tax bracket, the tion is generally the replacement value or Foundation was pleased to receive gener- more potential for tax savings. the cost basis of the policy. ous bequests from three GSA members. Gifts of stocks, bonds, mutual Gifts of retirement plan assets Clyde T. Hardy, Horace R. Blank, and Ray- funds, and real estate that have appre- can be arranged through naming GSA mond Woods all held GSA dear to their ciated in value and are owned for more Foundation as a beneficiary of your retire- hearts, and as a result, they had made the than one year can result in triple tax sav- ment plan or IRA (Individual Retirement important decision to include GSA Foun- ings. You may receive an income tax Account). This option is especially effec- dation in their wills. Regrettably, because deduction on the market value, not the tive in minimizing estate taxes. Retire- they did not notify us, we were never able original price, of the securities or real ment assets can also be placed in charita- to extend our appreciation to them. estate. You bypass any capital gains tax on ble trusts, maximizing your financial and While many of us do not consider the gain or growth since the time of pur- estate planning benefits. ourselves to be “major benefactors,” we chase. Opportunities for state capital gains Life income gifts can be made can often create significant charitable gifts tax savings may also be available. through charitable remainder trusts, chari- through planning. Most large gifts need to Bequests provide a way for you to table lead trusts, charitable gift annuities, be planned by you and your advisors to remember GSA Foundation in your will and pooled income funds. These arrange- ensure the best results for your financial and can reduce your inheritance taxes. ments offer substantial tax savings while plan and your estate plan. There are many Your will can designate gifts of cash, secu- providing an annual income to you, your ways to make a significant gift to GSA rities, or other property, or a percentage of family, or others. When appreciated assets Foundation and maximize the impact of the remainder of your estate. The sug- or property are placed in these arrange- your gift. We urge you to let the Founda- gested legal wording is: ments, the assets are reinvested and diver- tion know when you have taken this For a specific bequest: I leave sified and may produce a greater yield for important step so that we can properly [dollar amount] to the Geological Society of the donor or beneficiaries. acknowledge your generosity during your America Foundation, Inc., P.O. Box 9140, For more information, please lifetime. Any planned gift gives you Boulder, CO 80301, to be used for general contact Julie Wetterholt, Director of entrance to our planned giving club, the purposes. Development, GSA Foundation. Pardee Coterie, where we show our appre- For residual bequests: All the rest, ciation for your long-term investment in residue, and remainder of my estate, real GSA. Here are just a few of your options and personal, I give, devise, and and the potential tax benefits to you and bequeath to the Geological Society of your loved ones. (Be sure to consult your America Foundation, Inc., P.O. Box tax or financial advisor for information on 9140, Boulder, CO 80301. Digging Up the Past your individual situation.) Gifts of life insurance Most memorable early geologic experience can be made in the form of a new Planned Giving Options policy or an existing policy. Pre- “Between my freshman and sophomore and Benefits miums paid by the donor on a years at Indiana University, I assisted a donated life insurance policy graduate student in mapping the area Cash gifts are the simplest and most qualify for charitable tax deduc- around IU’s new field station in effective way to give to GSA Foundation. tions. If an existing policy is paid Montana” You can receive a full tax deduction for in full, your charitable contribu- —Raymond J. Pickering the amount of your cash gift in the year you make your gift, subject to certain tax

Enclosed is my contribution in the amount of $______. GSA Please credit my contribution to the: Unrestricted Fund Foundation Other: ______Fund I have named GSA Foundation in my will.

PLEASE PRINT 3300 Penrose Place P.O. Box 9140 Name ______Boulder, CO 80301-9140 (303) 447-2020 Address [email protected] City/State/ZIP ______

Phone ______

24 GSA TODAY, August 2000 Donors to the Foundation, May 2000 aland Claude C. Albritton Memorial Jack O. Colle e Ro Jane Christman Albritton Ann Marie Cox Z Robert F. Diffendal Jr. c Biggs Excellence in Earth Science Henry James Dorman k Education w Avery Ala Drake Jr., in memory s Curtis G. Lindsay in memory of e

of Hal James and George Viele ! Professor John Lemish N Hugh White Dresser Shirley Dreiss Memorial W.G. Ernst Stephen J. Urbanik Helen L. Foster Gerald M. Friedman* Farouk El-Baz Fund Sharon Geil◆ Diane M. Cozzi Richard Goldsmith* Patricia C. Grodzki Richard Hamburger Earth Science Ventures Arthur D. Howard Fund Gilmor S. Hamill IV* in memory www.nzrocks.com Kurt Servos* of Augustin Pyre George Fulford Hanson Richard H. Jahns Distinguished Guided field trips on an Thomas L. Holzer* Lecturer Nobuhiro Imoto ac ive plate boundary Charles W. Welby* t Ralph O. Kehle ◆ Educational adventure in J. Hoover Mackin Award A. David Kendrick Bruce H. Bryant* Bart J. Kowallis association with Victoria Konrad B. Krauskopf** John T. & Carol G. McGill Fund University, Wellington. Chia-Yu Lu Christopher F. Erskine Reese E. Mallette◆ ACTIVE TECTONICS field camps. Minority Fund Candace S. Martinez ACTIVE VOLCANISM field trips. A. Wesley Ward Peter H. Masson* Margaret W. Matlin in honor of my ANTARCTIC RESEARCH ASSISTANTS North-Central Section Endowment father, Donald Edward White, for MARINE RESEARCH CRUISES Sharon Geil◆ his 86th birthday DIRECTED BY ◆ Publications Marlene L. McCauley BRAD ILG PhD, NZ and US geologist Jon Olsen** Judson Mead* LES SINGH NZ geologist Paulus Moore** Research Grants Michael J. Murphy Mehdi Alavi* Grover E. Murray in memory of Samuel Shoemaker Memorial for Crater Ellison Jr. and Roger T. Saucier Sherwood D. Tuttle* Studies Virginia S. Neuschel Jane H. Wallace** Robert A. Cadigan Jack E. Oliver** A.L. Washburn* Elmer D. Patterson Southeastern Section Endowment Karl W. Wegmann Ralph B. Peck** A. David Kendrick Malcolm P. Weiss** William L. Petrie* Robert C. Whisonant◆ John H. Weitz* Michael S. Petronis John A. Willott Unrestricted Claire A. Richardson David F. Work*◆ Ewart M. Baldwin Jack C. Rosenau John L. Wray Matthias Bernet Paul K. Sims Paul W. Zimmer Darinka Zigic Briggs Timothy M. Smith A. Ewan Campbell Holly J. Stein *Century Plus Roster Lawrence R. Cann Richard C. Stenstrom (gifts of $150–$249). Keros Cartwright* Mary Wilder Stoertz **Penrose Circle (gifts of $250 or more). William L. Chenoweth Donald A. Swanson ◆ James B. Coffman** Joshua I. Tracey Jr.* Second Century Fund.

GSA Member Service Center One-stop shopping for all your GSA needs! E-mail: [email protected] Buy a GSA publication Update your mailing address Register for a GSA meeting Get the information you need Phone: (303) 447-2020, ext. 774 • Fax: 303-443-1510 Toll-free: 1-888-443-4472 • Web: www.geosociety.org

GSA TODAY, August 2000 25 The Father of Modern Volcanology: Howel Williams (1898–1980)

Alexander R. McBirney, Department of Geological Sciences, University of Oregon, Eugene, OR 97403-1272

Though known to most of his friends as “Willie,” the title With his geol- Howel Williams cherished most was one given to him by his stu- ogy degree came dents on the occasion of his retirement: The Last of the another scholar- Ordovices. I think it appealed to him because it reflected his ship that enabled Welsh background and his role as one of the last members of a Williams to fur- passing era. ther his studies at Williams’ 50-year career spanned a period of dramatic Imperial College. changes in the sciences, especially geology. Through his own con- There, working tributions and those of his students, he was largely responsible chiefly under for the emergence of volcanology as a rigorous branch of modern W.W. Watts, he science. Although his work was in a classic style that we seem to completed a Howel Williams, 1961. have lost, perhaps forever, few have left so pervasive an imprint detailed study of on their fields. Even fewer have inspired wider admiration or Snowdon in North deeper affection. Wales. The abundant Ordovician volcanic rocks he encountered Born in Liverpool, England, Williams was raised along with there and in the area near Capel Curig aroused his interest in vol- his identical twin, David, and six other children in a modest, canism and led him to the classic volcanic fields of the Eifel dis- middle-class household. He spoke only Welsh until the age of six. trict of Germany and the Auvergne in central France. He returned His scholastic honors in secondary school won him a scholarship with a firm resolve to make volcanic geology his principal work. to the University of Liverpool where, despite an interruption for Thanks to a fellowship from the Commonwealth Fund, Williams military service from 1917 until the armistice in 1918, he was able to devote the next two years to studies with A.C. Lawson received his bachelor’s degree with first-class honors before the at the University of California at Berkeley. Apart from a single age of 20. Though his initial studies were in geography, Williams seminar dealing with the geology of California, he took no for- soon developed a keen interest in archaeology, which in turn, by mal courses while at Berkeley, devoting his time instead to field a singular chain of events, led him to geology. studies. He concentrated on the ancient volcanoes of the Sutter While engaged in excavations of a Roman camp site in Buttes in the Sacramento Valley of California and on Lassen Peak, northern Wales, Williams observed that the floor of the baths was a recently active volcano in the southern part of the Cascade paved with slabs of slate rich in curious fossils. Anxious to learn Range. In addition to all this, he found time to visit Hawaii and where the Romans had quarried the slate, he consulted P.G.H. Tahiti. Boswell of Liverpool’s Department of Geology. It so happened In 1928,Williams returned to Britain to take his D.Sc. in geol- that Boswell was then studying the Silurian rocks of Denbighshire ogy at the University of Liverpool. He then spent two years on and, from the nature of the distinctive graptolites in the slate, the staff of Imperial College before returning to America to join immediately knew its source. Williams was so impressed with this the faculty at Berkeley in 1930. There, he rose to the rank of full instant solution to his problem that he began to sit in on lectures professor in only seven years. Between 1945 and 1949, he served in geology and in 1924, after receiving his M.A. degree in geogra- as chairman of the Department of Geology, doing much to raise phy, went on to earn an M.S. in geology. the quality of its faculty, teaching, and research. It was largely his influence during these critical years that set the course of the department and brought it into the ranks of leading American institutions. He was elected to the National Academy of Sciences in 1950. Williams continued his studies of volcanoes in the western United States, particularly Crater Lake, where his work formed the basis for two of his most important contributions, a monograph on Crater Lake and a general treatise on the origins of calderas. The rapid succession of papers that he produced during this period included

Howel Williams, left, and Alexander McBirney use the hood of a jeep as a place to plot the geology on their map of Honduras.

26 GSA TODAY, August 2000 several that soon became classics of volcanology. He dealt with Many have commented on his instinctual ability to find the criti- volcanic domes, the classification of pyroclastic rocks, the cal outcrop that resolved a puzzling question. With his uncanny Pliocene volcanic centers of the Navajo-Hopi region, and several eye for landforms and the regional significance of lithologic vari- large volcanic centers of the Cascade Range, including Newberry ations, he could synthesize the volcanic history of a broad region Caldera and The Three Sisters. from a few seasons of field reconnaissance and petrographic anal- In 1943, when the volcano Paricutin was born in a Mexican yses. cornfield, Williams joined a group of geologists recording its In addition to regional field studies, Williams produced a growth and evolution and completed a reconnaissance study of widely used textbook on petrography in 1954, and, in 1979, a more than a hundred similar cinder cones in the surrounding comprehensive treatise on volcanology. The former was the result region. This was the beginning of the work in Latin America that of collaboration with Frank Turner and Charles Gilbert at the absorbed much of his energy for the remaining years of his University of California; the latter a product of the years he spent career. He found there several opportunities to apply his geologi- with me at the University of Oregon after his retirement from cal experience to problems in archaeology. While in Mexico he Berkeley. Published only two months before his death, Volcanol- used petrographic techniques to discover the source of stone used ogy summed up a lifetime’s experience and, despite more recent in the giant Olmec sculptures of La Venta near the Gulf of Mex- advances, is still regarded as one of the most comprehensive ico. In 1950, with the support of the Carnegie Institution of works on the subject. Washington, Williams went to Nicaragua to examine the extraor- Williams’ most conspicuous personal trait was his sparkling dinary ancient human footprints in a hardened volcanic mud- wit and unfailing sense of humor. Until one became acquainted flow near Managua. with him, his jokes could be disconcerting. Encountering one of I was living in Nicaragua at that time. I had started a coffee his students crossing the campus he might ask, “Why are you farm in a remote part of the country and, while waiting for the wandering about at this hour wasting valuable time? You should trees to mature, took a job with a mining company. Though be in your office working!” Or, upon entering a laboratory, he totally ignorant of geology, I was given the task of exploring an would pretend to check the settings of the instruments and offer area near the volcanic chain to develop geothermal power for the a “correction factor” in the form of a complex differential equa- mine. My boss asked Williams to let me accompany him in the tion incorporating the effects of daily weather conditions on ana- field for a week or so in order that I might learn some rudimen- lytical results. But beneath his jovial manner there was a personal tary geology. During the day, we explored the geology of the area, reserve that only those who knew him well could fully appreci- and in the evenings Williams tutored me in volcanology and ele- ate. His irreverent wit concealed an uncompromising code of per- mentary petrology. His enthusiasm and lucid explanations sonal conduct. aroused my interest and ultimately led me to study under him at A natural scientist in the classical tradition, Williams stressed Berkeley. After I obtained my degree, we worked together until meticulous observations, thorough research, and sound interpre- his death in 1980. I was not the only student to be captivated by tations presented in elegant, lucid prose. With his ability to read his enthusiasm for volcanology. In the course of his long career, geological literature in English, French, German, or Spanish, he Williams fostered a succession of students, many of whom went could trace the historical development of ideas and synthesize on to become leaders in their fields. diverse views with simplicity and clarity. The same qualities per- Williams’ work in Nicaragua was the beginning of a succes- vaded his teaching. His courses in petrography and regional geol- sion of regional studies which, though less widely known than ogy were enlivened with amusing historical anecdotes and illus- his work on calderas and domes, were even more remarkable, trated by artistic hand-drawn diagrams that left an indelible both for their scope and for the extent of their contribution to impression on hundreds of students. the previously little-known geology of Central America. These In the closing years of his life, Williams saw the classical studies, together with a survey of the Galapagos Archipelago methods of scholarship give way to complex geochemical investi- completed in 1969, covered large regions where few, if any, geolo- gations and thermodynamic calculations compiled on computers gists had gone before. The studies allowed us to start from and reported in hastily prepared, multiauthored papers of tran- scratch, working out broad structures, regional stratigraphy, and sient interest. Although he himself contributed to this change the evolution of an entire volcanic province. Less interested in and on balance approved of it, he inspired in his students a the eruptive phenomena of active volcanism than in broad struc- respect for the traditional standards that make his work stand tural and lithologic relations, Williams had a masterful ability to out, even today, as enduring contributions to volcanology. ■ decipher the form and past activity of large volcanic complexes.

Howel Williams’ hand-drawn illus- trations of petrographic thin sections helped thousands of students understand the textures and mineral assemblages of rocks as they are seen under the microscope.

GSA TODAY, August 2000 27 LETTERS

Mojzsis and Harrison (“Vestiges of a Beginning: Clues to the Mojzsis and Harrison reply: Berndt et al. (1996) reported the reduc- Emergent Biosphere Recorded in the Oldest Known Sedimentary tion of CO2 to methane and higher hydrocarbons formed under Rocks,” GSA Today, v. 10, no. 4) stated that methane in experiments reducing conditions according to the reaction: olivine = serpentine + from Horita and Berndt (1999) may have been derived “exclusively magnetite + H2. In attempting to reproduce the results of Berndt et al. from bio-organic contaminants in the reactant olivine” and cited (1996), McCollom and Seewald (1999) stated that, “isotopic labeling McCollom and Seewald (1999) to support this view. While Mojzsis and blank experiments indicate that the most likely source of the and Harrison’s interpretation of isotopically light carbon in Archean observed hydrocarbons is decomposition of trace contaminants metasediments could well be correct, we object strongly to the notion rather than abiotic synthesis.” We acknowledge that McCollom and of biologic contamination in our experiments. In particular, methane Seewald (1999) in fact were claiming that the results of Berndt et al. production was monitored before any NaHCO3 was injected into our (1996), and not Horita and Berndt (1999), are due to bio-organic experiments, and no significant contamination was observed. Con- contamination of the reactant olivine. version of dissolved CO to CH commenced immediately after the 2 4 References Cited NaHCO3 was injected and occurred on a scale that would overwhelm any potential contamination from other carbon sources. Further- Berndt, M.E., Allen, D.E., and Seyfried, W.E. Jr., 1996, Reduction of more, McCollom and Seewald (1999) reported preliminary results and CO2 during serpentinization of olivine at 300 °C and 500 bar: Geol- interpretations from an isotope tracer experiment that was performed ogy, v. 24, p. 351–354. to help quantify sources of methane produced during hydrothermal Horita, J., and Berndt, M.E., 1999, Abiogenic methane formation and alteration of olivine. Horita and Berndt’s experiments did not involve isotopic fractionation under hydrothermal conditions: Science, v. the reactant olivine so the two studies are unrelated. Therefore, Mojz- 285, p. 1055–1057. sis and Harrison’s reference to our study is unfounded. McCollom, T.M., and Seewald, J.S., 1999, Rapid equilibration of CO References Cited 2 and formate under hydrothermal conditions (with a comment on the Horita, J., and Berndt, M.E., 1999, Abiogenic methane formation and abiotic synthesis of hydrocarbons during serpentinization): Geologi- isotopic fractionation under hydrothermal conditions: Science, v. cal Society of America Abstracts with Programs, v. 31, no. 7, p. A-431. 285, p. 1055–1057. Stephen J. Mojzsis, T. Mark Harrison McCollom, T.M., and Seewald, J.S., 1999, Rapid equilibration of CO2 University of California, Los Angeles and formate under hydrothermal conditions (with a comment on the Los Angeles, CA 90095-1567 abiotic synthesis of hydrocarbons during serpentinization): Geologi- cal Society of America Abstracts with Programs, v. 31, no. 7, p. A-431. Michael E. Berndt University of Minnesota Minneapolis, MN 55455

28 GSA TODAY, August 2000 New GSA Fellows Elected by action of Council, May 2000

E. Arthur Bettis III Sara S. Foland Susanne U. Janecke Robert S. Nelson John C. Butler Charles T. Foster Jr. Joseph T. Kelley Gary A. Smith Carl N. Drummond Craig R. Glenn Lawrence A. Lawver David R. Soller Richard G. Fairbanks Paul Goldberg Lance D. Miller

New GSA Members The following members were elected by Council action during the period from October 1999 through February 2000. (Those who transferred from Associate status appear in boldface type.)

Pedro A.A. Abreu Richard A. Bieber Patrick M. Carr Dawn Gordon Davis Seth D. Ackerman R. Jason Biga Charles W. Carrigan Jana L. Davis Richard G. Adair Wendy Bigler Chris J. Carroll Tammy K. Davis Tim J. Agnello Jason D. Blair Monica Carroll Sharon K. Day David G. Agresti William J. Blanford Christopher J. Carson Jacob J. De Moor Shawkat Ahmed Shawn D. Blocker Christian Rene Carvajal Krysten M. DeBroka Laurent Ailleres Charles L. Blount Isla S. Castaneda John deLaChapelle Abdulaziz A. Alduaiji Kevin G. Boggs Peter J. Castiglia Brian A. Dempsey Khalid D. Aldulaimi Janice L. Boller Daniel W. Casto Jack M. Denman Michael C. Alfieri Phillip R. Bonneau Maria C. Castro Devin P. Dennie Muna Al-Samit Leslie A. Boockoff Aaron J. Cavosie Jill N. Densmore Patricia A. Aluskewicz Lawrence H. Boram Timothy C. Chao Edward Derbyshire Melissa A. Amentt Josh W. Borella Dawn M. Chapel Ann Marie Diana Alison M. Anders Thomas J. Borra William J. Chazey III Robert F. Dias Michael T. Applegarth Rachelle M. Boskie Daniel P. Childers Thomas G. Diener Yuji Arai Benjamin C. Bostick Ryan D. Christensen Brad E. Dingee Will J. Arcand Sarah E. Bowser Eric H. Christiansen Phillip A. Dinterman Christopher S. Armistead Christine F. Braban Nathan I. Chutas Ginger S. Dodson Kim F. Ashley Raymond Brady Gabriel Cisneros Jan M. Dodson Wade L. Aubin Terry T. Brawner Henry P. Clauson Rachel A. Dolbier Seth D. Axkerman Jill M. Bries Claudine Cohen Weiquan Dong Robert Ayuso Jason P. Briner Lorrie V. Coiner Jeffrey P. Donnelly Mohammad A. Baaheth Amy L. Brock Joseph P. Colgan Shawn M. Donovan Jennifer S. Bachman Simon H. Brocklehurst Jeremiah Collier Gary G. Dorch Christopher T. Baldwin James W. Brode Deanna M. Combs Cathryn M. Dowd Bridget A. Ball Michael E. Brookfield Christopher E. Connell Besim Dragovic Abdullah Bamousa Mark J. Brooks David L. Cook Hilary A. Dria Fred F. Barber Bruce E. Broster Mary J. Cooke John A. Dunbar Gary G. Bard Carolyn H. Brown Chad D. Cooper Gita Dunhill Bill Barker Christina M. Brown Tammi L. Corchero David L. Dunn Charles F. Barker Scott R. Brown Jeremy J. Coughlin Regan E. Dunn Peter E. Barkmann Ian D. Browne Brendan T. Cox Jacob F. Dunston Jason B. Barnes Andrew L. Brownstone Julia E. Cox Sara H. Durall Warren Barrash Anna Carol Bryant Samuel J. Coyner Fritz Ehlers John M. Bartos Jr. Gerald C. Bryant Nancy M. Craft Freddi Jo Eisenberg Tomasz K. Baumiller Robert Buchwaldt Timothy E. Craske Chris L. Eisinger Jason B. Baxter Rosalice Haberman Buehrer Walter L. Cressler III Douglas D. Ekart George J. Bayer Stefan Burde Allison L. Croley Nicole A. Elko Blakely R. Bear Elane Burger Benjamin T. Crosby Carrie M. Elliott Bennett L. Bearden David K. Burton Carl C. Crouch Michelle L. Ennen Darren L. Beckstrand Mark J. Burwell Michella C. Crown David Escamillo Anthony J. Bednar Peter A. Buscemi Xiaojun Cui Emily E. Evans Peter C. Beeson Andrew B.G. Bush Shane D. Cummings Christine E. Ewell John G. Begg Darryl J. Butkos Heather S. Cunningham Adrian I. Ezeagu Mikala S. Beig Sonya A. Cadle Alexis T. Cupo Brian A. Fagnan Anthony L. Benson R. Scott Calhoun Jason W. Currie Robert A. Fair Kirsten E. Benson Hilario Camacho-Fernandez Kirsten B. Cutler Claudia C. Faunt David W. Berry Guillermo A. Camargo Paul M. Cutler Mark H. Ferguson Shawn P. Beskar Carl E. Campbell Huntly N. Cutten Dan Ferdinand D. Fernandez Robert A. Bevilacqua Terrance P. Campbell Steve J. Czehura George A. Filpovich Karen M. Bezusko Luigi Carmignani Dana M. D'Amato Janok P. Bhattacharya Stephanie M. Carney David J. Dariano New Members continued on p. 30

GSA TODAY, August 2000 29 New GSA Members Laurie A. Hankins Charlotte E. Kelchner Emily W. Lowe continued from p. 29 Jon Harbor Jeffery D. Kelley Silong Lu Carol P. Harden Russell R. Kelly Richard R. Luckey Ismor Fischer Allen L. Hardy Sarah E. Kelly William M. Lukens Marc E. Flanagan Robert N. Hargett Stephan Kempe Meghan Lunney Sascha Floegel Rick H. Harvey Rebecca Kempthorne Donald L. Macalady Lee J. Florea Thomas A. Hauge James A. Kessler R. Patrick MacDaniel Patrick S. Florence Shawn D. Haven Cynthia L. Kester Campos E. Madrigal Jurgen Foeken Eric J. Hawkins Todd A. Keyser Mariah L. Mailman Geoffrey K. Force Wenwu He Eugene Khain Aaron J. Mango Kathryn Ford Joseph P. Hebert Steven B. Kidder Len C. Mankowski Mike J. Formolo James A. Heller Daniel E. Kile Andrew H. Manning Donald J. Foss Dennis R. Helsel Marvin B. Killgore Nasser M. Mansoor Andrea L. Foster Richard K. Herd Eric L. King Jeffrey D. Manuszak Brent D. Foster Martha C. Herzog Jack T. King Marci M. Marot Otina C. Fox Scott D. Heule Maria Elena King Todd L. Marsh Thomas J. Franko Jason F. Hicks Chad A. Kinney Deborah A. Martin Vicky L. Freedman Melissa K. Hicks Shiloh L. Kirkland John M. Martin Jason French Franz K. Hiebert David J. Kistner Mark W. Martin Carl R. Froede Jr. David Hilburg Irene J. Klaver Kyle Martinez Qi Fu Michael R. Hilton Brian N. Klawiter Bettina Martinez-Hackert James W. Funderburk David A. Hindle Amber L. Kleeschulte Brigette A. Martini Jordan E. Furnans Martin Hoffmann Johan Kleman Walter W. Matyskiela Kristin E. Gager Heidi L. Hoffower Yvonne M. Kline Jennifer E.P. Matzel Vanessa G. Gale Albrecht W. Hofmann Brian D. Knight George F. Maxey Amitava Gangopadhyay Christopher S. Holm Raymond L. Knox Paul S. Mayer Antonio F. Garcia Michael Holz Rich D. Koehler III Kevin K. McAleer W. Brent Garry Kevin D. Hon Alan E. Koenig Jeremy P. McCartha Phillip D. Garwood Ted W. Hopkins Peter O. Koons Bob S. McClellan Billie-Jo L. Gauley Christine A. Horch Frank W. Koot Richard Blaine McClesky Scott A. Geary Charles E. Houser Brian E. Kortz Craig R. McClung Anne M. Gellatly Chuck D. Howell Paula J. Kosunen Thomas M. McCollom Pamela A. Gemery Kenneth E. Howell Karen A. Koutrakos James A. McCombs Kenneth J. Gendron Xiumian Hu Natasha M. Kramer Richard T. McCrea Tim R. Gere Noah D. Hughes Richard A. Krause Bret A. McDaniel Norman J. Gern Debbie N. Huntzinger Rita K. Krebs Heidi L. McDonald Susan B. Ginsberg Joel A. Hurowitz Donathon J. Krier Trent A. McDowell Edward C. Girard Olafur Ingolfsson Jill C. Krukoski Sean P. McGinnis Lesley S. Glass Scott E. Ishman Piotr Krzyszton Amber N. McIntosh Lisa A. Glonek John A. Izbicki Monte L. Kuhn Mark S. McKillop Raymond J. Goldie Jacq Marie Jack Thomas K. Kuhn Christopher T. McLain Michelle F. Goman Mahipalsinh R. Jadeja Gene A. Kurz Brian J.O.L. McPherson Luis Antonio Flores de Dios Windy L. Jaeger Tammy Kutzmark Nadine McQuarrie Gonzalez William H. Jahn Dennis G. Kyhos TJ Meehan Ann M. Gooden Bruce M. Jakosky Nicholas F. Labedzki Jesse J. Melick Raymond M. Gorka Robyn E. Jamieson David M. Lamb Maura A. Metheny Richard R. Gottschalk Aleksandra G. Janik Ryan P. Lanclos Debbie W. Michael Nancy C. Grainger Gi-Young Jeong Darrell I. Leap Rachel E. Miller Helene M. Grall-Johnson W. Wynn John Ernest B. Ledger Andrew M. Miner Sara E. Gran Amy M. Johnson Gwang Hoon Lee Joseph M. Minervini Karen L. Greengrass Edward Johnson Meng-Yang Lee Thomas E. Miskelly Jr. James P. Greenwood Hal E. Johnson III Frank Lehmkuhl Molly L. Mistretta Phyllis E. Gregoire Jean M. Johnson Melissa E. Lenczewski Carl Mitchan Yvonne K. Griffin Marie C. Johnson Joy Lester Ricardo J. Molinero Elizabeth A. Grischkowsky Molly M. Johnson Jiang hai Li Fred J. Molz III Peggy M.K. Gross Natasha M. Johnson John S. Lien John A. Moody Heidi A. Guetschow Ashanti Johnson-Pyrtle Colleen E. Lillie Bret S. Moore Cathy Jean Guffey Kim Jolitz Fara Lindsay Bruce R. Moore Sandor Gulyas Mary H. Jolly C. Blair Linford E. Anthony Morales Jeff E. Gutsell Daniel L. Jones Vanesa D. Litvak Maria T. Moreno Erich D. Guy Matthew L. Jones Darren R. Lockhart Carrie Morrill Charles G. Haag Thomas E. Jones Steven P. Loheide William R. Morris Omid Haeri-Ardakani Thomas A. Jones Alberto M. Lopez Nilendu S. Mukherjee William R. Halliday J. Matthew Justice Elsa R. Lopez Roland Mundil Matthew J. Hammer Karyn Lyn Kasprzak Gloria I. Lopez Mandy J. Munro-Stasiuk David J. Hammond Randy L. Kath Mark L. Lord Brendan Murphy Lijie Han Martha H. Kauffman Maria A. Lorente Asif Muzaffar Paul C. Hancock Shin-ichi Kawakami Barbara L. Lorenzo-Rigney Russell E. Myers Jacqueline J. Hand Baxter F. Kean Guillaume P. Lorilleux Elisabeth S. Nadin Jordon D. Hand Jonathan P. Keizer Vivian S. Lovern Pradeep K. Naik

30 GSA TODAY, August 2000 Thet Naing Dean A. Pearson Oren C. Reedy E Joseph Schultheis Barbara A. Nall Donghong Pei D. Matthew Reeves Kristin A. Schultheis Erica M. Napoleoni Alfred H. Pekarek Stephan M. Regenfuss Angela M. Schultz Keshaw Narine Jon Damien Pelletier Sonya M. Remington David Schultz Daniel L. Narsavage Elizabeth A. Pendleton Andrew J. Rich Dirk Schulze-Makuch Michael Tyler Naus Marta Perez-Arlucea Timothy I. Richards Stephanie J. Schwabe Luis Fernando Navarro Matthew S. Pesci Russell V. Richmond Janet B. Schwarz Ron L. Nellermoe Richard A. Peters Alan C. Riggs Judith G. Scotchmoon Robert W. Nierste Steven M. Peterson Vincent R. Rinterknecht Rebecca L. Scott John R. Nimmo Gary T. Petro David C. Rivers Russell W. Scranton David A. Nonnast Karin Peyer John R. Robertson Jeffrey S. Seewald Andrew T. Norton John C. Pfeiffer Joseph D. Robertson Amy J. Selting Rain G. Nourne Christine M. Philips Kenneth R. Robitaille Matthew A. Senese James H. Nyenhuis Warren P. Phillips Nikolai N. Romanovsky Yongkoo Seol Grady M. O'Brien Thandar Phyu Cameron S. Rombach Beverley L. Shade Joy D. O'Donnell Jennifer L. Pierce Heath C. Roscoe Sheila A. Sharp Churchill O. Okonkwo Tatana K. Pinegina Jodi E. Rosoff-Berkowitz Robert J. Shedlock Paul M. Olesen Sergei Pisarevsky Kirk C. Ross Anne F. Sheehan Brooke E. Olson Joy Pochatila Joel W. Rotert Stephanie L. Shepherd William R. Oppermann Christopher Poitras Cara L. Roush Bruce A. Sherman Kevin D. Orabone Leonid Polyak Alakendra N. Roychoudhury Jerry Shi Patrick J. Orr Robert J. Poreda Richard W. Ruhanen Jr. Mingjuan Shi S.E. Orrell David F. Porinchu Sandy Rushworth Donna J. Shillington Peter Orvos Jacob L. Porter Sandra E. Ryan David J. Shoore Aleeza H. Oshry Olivia A. Posner Sarah J. Ryker Therese Shryane Gordon R. Osinski Victoria A. Pretti Nicholas J. Salkowski Emily Silverman Michael E. Oskin Belinda K. Price Carma A. San Juan Craig Trevor Simmons Amy L. Ott Brian M. Priest Aaron L. Sanford Jeffrey M. Simonsen Penelope M. Padmore Michael C. Puchalski Thomas Saucede Deke C. Siren Betty E. Paepke Tamalyn Pulsipher Heather M. Savage William J. Skinner Mia A. Painter Laura C. Quinn Sherry L. Schaaf Lee D. Slater Scott L. Painter Philip D. Rabinowitz Ricky A. Schaeffer Garrett E. Sleeman Eungyu Park Cynthia M. Rachol Jennifer J. Schellpeper Peter A. Slovinsky Sheila N. Patek John Ragsdale John V. Scherer Donald W.L. Smellie Jason R. Patton Jeffrey M. Rahl Stephanie A. Schlosser Erik A. Smith Jeremy A. Pavlish Emilia M. Ramirez Kevin M. Schmidt Randall L. Paylor Stephen G. Redak Chris L. Schneider New Members continued on p. 32

— Attention GSA Exhibitors and Advertisers —

YOUR MARKET WHO: GSA advertising and exhibiting supporters who want to … WHAT: Reach those who attend the GSA 2000 Annual Meeting in Reno AND remind the membership of your presence at the show! WHERE: The October issue of GSA Today is scheduled to be available on-site in Reno for meeting attendees to pick up! And, the February 2001 issue of GSA Today will feature a full-color wrap up of the Annual Meeting. Both are bonus distribution issues! WHEN: Reserve your space now! Space reservations Oct issue: Aug. 20 (art due Sept 5). Feb. issue: Dec. 20 (art due Jan. 5). WHY: For less than a penny per reader you can be introduce attendees and GSA Today readers to your products and services. HOW: Contact GSA Advertising Coordinator Ann Crawford: 1-800-472-1988 x153 by e-mail: [email protected]

Exhibitor/Advertisers: Call to learn how you can receive a 10% discount on space rates for these issues.

GSA TODAY, August 2000 31 VISIT OUR WEBSITE www.meijitechno.com

New GSA Members Robert S. Terefenko Colby J. VanDenburg Lester J. Williams continued from p. 31 Richard E. Terry Darrel A. Vandeweg Matthew A. Wills Leanne S. Teruya Ryan G. Vannier Anna B. Wilson Kevin H. Smith Michael M. Thacker Angela M. Vasquez John R. Wilson Michael E. Smith Mark H. Thiemens Florence R. Vaughan Judy L. Wilson Charles B. Snell Christopher W. Thomas Philip L. Verplanck Demian E. Wincele Bogie Soedjatmikoet John T. Thomas Warren Dean Vestal Timothy R. Wineland Gary S. Solar Ryan D. Thomas Marilyn B. Vogel Brian L. Wingard Anton I. Sotirov Sabine F. Thomas Stefan W. Vogel Michael T.D. Wingate Michael Sperazza Anna Thompson Michelle L. Volosin Deborah H. Winiarski Anne T. Spires Jennifer L. Thompson George Voulgaris Lee Winters Dale K. Splinter Joseph A. Thompson Bradley R. Wakoff Ivana C. Witt Thomas W. Stafford Jr. Allison M. Thomson Eric L. Walston Chad A. Wittkop Beverly D. Stambaugh Trista L. Thornberry Bronwen Wang John A. Wolff Heather I. Evenstar Stanton Anne C. Tillery Jianlin Wang Ansley Wren Kerrilyn P. Steck Sarah E. Tindall Yumei Wang Joanna L. Wright Edward G. Stermer Beth K. Tober Jacob S. Waples Michael B. Wyatt Dion C. Stewart Keryn Tobler David J. Warren Wenjiao Xiao Traci L. Stokes Eric Tohver H. Patricia Warthan Claire A. Yannacone Alan G. Stone Kenneth P. Tomlin Jeffrey P. Waters Nicole D. Yarger Balin B. Strickler Max A. Torres Gordon R. Watt Hideyoshi Yoshioka Randolph C. Stuart James C. Trask Lars Weiershauser Graham A. Young Bonnie W. Styles Steven T. Travers Beth N. Weisenborn Leah D. Young Raden Sukhyar Selina Tribe Brian C. Welch Kate E. Zeigler Toni B. Superchi Alec J. Tsongas Susan A. Welch Daniel L. Zeltner D. Matthew Surles Courtney H. Turich Stanford R. Weltner Hongwei Zhang Michael R. Taber Henry L. Turner III Amy T. Welty Yue Zhao Jocelyn R. Tamashiro Bradley Scott Tye Kemble White Li Zheng Charles J. Tapper Michael A. Ukynowicz Steven W. White Cathy L. Zumsteg Jason M. Taylor Ryan W. Vachon Laurie A. Whitesell Ryan Z. Taylor Shelby R. Valenzuela Jaime S. Whitlock Lora Teitler Peter M. Valley Donald O. Whittemore Maria J. Teixeira Christopher M. Van de Ven J. David Wildharber

32 GSA TODAY, August 2000 Geological Society of America

GSA will feature great science at Summit 2000!

Pardee Keynote Sessions (invited speakers) This year’s Pardee Keynote Symposia features eight topics of broad interest to the geoscience community.

Sessions for Monday, November 13, and Tuesday, November 14: K1 Geology in the New Millennium Sample return missions, new in-situ geo- mance prediction and how scientists can I: Resource Collapse, Environmental logical tools, and the return of human communicate the science and its uncer- Catastrophe, or Technological Fix? geologists to alien outcrops promise to tainties to nonscientists and policymakers. Stephen L. Gillett, Mackay School of revolutionize planetary geology in the ORAL coming decades. Presentations by project Mines, Reno, Nevada. Monday, November K6 Living with Uncertainty: 13, 8 a.m.–12 noon. scientists will introduce and discuss Scientific, Political, and Societal upcoming or planned planetary missions Perspectives Is the 21st century headed for catastrophic that exemplify the translation of tradi- GSA Institute for Earth Science and the resource shortages or environmental apoc- tional “hands-on” geology to other worlds, Environment. Christine Turner, U.S. Geo- alypse, as has been predicted since the including Mars, the asteroids, comets, the logical Survey, Denver, Colorado; Robert 1970s? Or will new technologies come Moon, and the Sun. ORAL onstream quickly enough to avert disaster? Frodeman, University of Colorado, Boul- This session contrasts both views, with K7 Nuclear Waste Disposal: der. Tuesday, November 14, 1:30–5:30 p.m. presentations both by leaders in various Bridging the Gap Between Science How does science understand uncertainty? emerging technologies and by those who and Policy What are society’s expectations concerning view resource shortages as imminent. GSA Hydrogeology Division. Jane C.S. Long, our ability to provide answers to societal ORAL Mackay School of Mines, Reno, Nevada; problems? Speakers in this symposium will K4 A New Age of Planetary Kevin D. Crowley, Board on Radioactive address: shifting priorities in hazards Exploration: Sample Returns, In Situ Waste Management, Washington, D.C.; research; how complexity changes our per- Geological Analysis, and Human Jean M. Bahr, University of Wisconsin, ceptions of nature; the promises and draw- Missions to Other Worlds Madison. Tuesday, November 14, 8 a.m.– backs of predictive modeling; public per- 12 noon. ceptions of uncertainty; and how the USGS GSA Planetary Geology Division. Ralph Center for Science Policy addresses these Harvey, Case Western Reserve University, What is the scientific process of developing issues. ORAL Cleveland, Ohio; Cassandra Coombs, Col- confidence in the long-term performance lege of Charleston, Charleston, South of a repository, and how does this process Check your September GSA Today for Carolina. Monday, November 13, 1:30– relate to the policy-making process? Two Pardee Sessions scheduled for Wednesday 5:30 p.m. panels will examine the science of perfor- and Thursday, November 15 and 16.

For a complete listing of Topical Sessions scheduled for GSA’s Annual Meeting in Reno, visit www.geosociety.org.

TIME ATTENTION, STUDENTS! CHANGE President’s Student Breakfast Reception Monday, November 13, at the GSA Annual Meeting 7:00 to 8:30 a.m.

GSA President Mary Lou Zoback invites all students registered Sponsored by for the meeting to attend a free breakfast buffet sponsored by ExxonMobil Corporation. Registered students will receive complimentary coupons redeemable toward the breakfast buffet and will be eligible for prize drawings. Hosted by GSA

GSA TODAY, August 2000 33 New GSA Student Associates The following Student Associates became affiliated with the Society during the period from October 1999 through February 2000.

Matthew A. Abahazi Rhiannon L. Crain William S. Hammon III Whitney N. Littleton Kelly B. Adams Christopher J. Crosby Dean A. Hancock Ashley J. Lucht Miriam R. Akselrod James H. Cunningham Ryan S. Haney Patrick Benjamin Luetkemeyer Amanda L. Albright Andrew J. Cyr David N. Harden Jeanette Lyman David L. Allen Ann C. Davis Christopher M. Hare Mandela A. Lyon Katie E. Amos Caroline A. Davis Brian S. Hartman Tyler W. Mace Philip S. Anderson Nicholas A. Davis Jessica S. Hartman John S. MacLean Tanya Ariowitsch Christopher M. DeCioccio Jason E. Heath Marc A. Macy Jennifer Aschoff Megan K. DeSmedt Gary L. Henry II Zoie Mahar Rebecca K. Atkinson Heather L. DeStefano Jonathan J. Hess Edward H. Marks Seth L. Atkinson John L. Dolde Cyndi D. Hilliker Aaron W. Marshall Nicole M. Badon Carolyn Domrose Bryan W. Hitchcock Joseph P. Matoush Margaret A. Bagby Franklin Dorin Robert F. Hopkins Kasey L. McCall Stefan Bagnato Kathleen E. Dotson Danielle M. Huminicki Brian McDaniel Megan S. Barnes Jason P. Dowdy Michelle A.E. Huminicki Benjamin A. McGinnis Jennifer A. Barrows Andrew J. Downs Katrina H. Hunter April D. McGreger Alexander J. Bartholomew Kelly A. Dreibelbis Bretagne N. Hygelund James B. McGuire Laura R. Bassani Kelly C. Driggers Alison M. Iwerks Rory D. McIlmoil Jason A. Batus Alison R. Duvall Laura E. Jacobs Danette McKenney Brian C. Bauer Amanda L. Eads Miriam A. Jaffee Traci L. McMillin Mark Beaman Mark J. Earnshaw Christina D. Jan Abigail V. McQueen Linda R. Bearss Daniel J. Eastmond Derek E. Janda Jodie L. Medico William C. Beck Jonathan K. Eaton Amanda L. Jenkins Brian A. Meley Kristeen M. Bennett Sandi L. Edwards Kristi M. Johannes Laura C. Merrell Jennings Berger Amanda I. Ellison Ernest L. Johnson III Sean C. Metz Aaron J. Berndt Mathew E. Elwell Sally C. Johnson Nicholas R. Meyer Amy K. Bingham Amy C. Englebrecht Gregory D. Joslin Ambre Kay Middleton Jennifer L. Blanton Jennifer D. Eoff Matthew L. Justus Joshua H. Miller Amanda L. Booth Timothy J. Ewing Julie C. Kafcas Joshua J. Miller Charles M. Bove David W. Farris Todd J. Kast Stefan M. Mitrovich Daniel T. Bowen Nicole A. Feldl Wesley T. Keller Matthew D. Mittenthal Kerry H. Bowen Chad A. Ferguson Laura C. Kellogg Robert F. Montgomery Melissa A. Boysun Christopher J. Finney Megan J. Kelly Jason C. Mooney Matthew M. Brabeck Ann H. Finocchio Bryan A. Kelpe Kevin R. Morrison Jeremy M. Brack Emily Rose Fojut Kathleen M. Keranen Ken P. Mueller Bethany A. Bradley Wesley H. Foll Shawn D. Kerr Glenn Mutti Paul T. Brandes Joshua D. Frank Shanna M. Kevorkian Emily A. Ness Jody L. Brandrup T.J. Fudge Julie C. Kickham Holly J. Nichols Stephanie M. Briggs Stephanie R. Fuentes Leyla D. Kirkpatrick Brian L. Nicklen Cassandra A. Brown Zamara Fuentes Jeff C. Kirtley Brian E. Nixon Rebecca J. Brown Sarah J. Fuller Georgia E. Knauss Eric D. Noreen Robert J. Brown Tina L. Gammill Renee J. Knecht Vanessa J. O'Brien Amy L. Bruggeman Claudia Garcia Joseph W. Knight Jay C. Odaffer Jennifer L. Bryson Nicoli Garner Karolyn J. Knoll Julie A. O'Leary James F. Bujno Jaime L. Garrand Lori A. Koehler Brandy R. O'Neill Brad A. Burdick Marcus O. Gary Sarah M. Koenigsberg Richard J. Orner Sarah R. Burton Marko Gellissen Matthew V. Kohlbecker Ernest Michael Oswalt Eric M. Butler Megan G. Gerseny Clifton R. Koontz Robert K. Outlaw Sean K. Canada Stacy A. Gilbreth Joseph P. Kopera Larry M. Owsley John M. Canerdy Emily M. Gilles Jesse T. Korus Brien K. Park Leigh Childs Cantey Samuel P. Gillet Seth C. Kruckenberg Wayne E. Patterson Elizabeth A. Carruth Rebecca E. Glatz Eric J. Kuhl Sandra C. Pavick Laura E. Chambers Tom P. Gleeson Angela R. Kurth Jennifer C. Payne Heung-ngai Chan Mary E. Gossage Gabrielle Elise Kurth Robert R. Perez Robert L. Chandler Francis M. Gough Sage A. Kutzman Paul A. Petersen Mark A. Chapa Greg F. Grabner Jae Jong Kwak Caryn A.O. Peterson Nicholas J. Chrobak Jason D. Graves Patrick S. Lam Nicholas M. Petruzzi Elizabeth A. Clark Jeanette M. Greenidge William J. Lambert Erin H. Phillips Sarah J. Clifthorne Bryant J. Griggs Alyssa A. Lanier Rebecca A. Pitts Alvin L. Coleman Jr. James D. Groesbeck Jr. Stephanie D. Larsen Jaime L. Piver James P. Conroy Jason D. Grubb Susan K. Larson C. Stephen Plant Mary Jane Coombs Lizbet Guijarro Jason T. Lennne Mark A. Plas Jennifer R. Cooper Richard J. Hall Jamie S.F. Levine Mary Beth Platt Rebecca L. Cox Julie M. Hamblock Noel C. Liner Philip A. Polk

34 GSA TODAY, August 2000 Meagen A. Pollock Abigail R. Spieler Sue M. Potter Issac D. Standard GSA Bulletin Adopts Rachael M. Potts Amy P. Stanik Timothy L. Pranger Charles M. Steele New Page Charge Policy Christina A. Progess Noelle A. Steele J. Gayle Pugh Donovan Steutel For all new manuscripts received by the GSA Bulletin after Lacie LaNeille Quintin Grant Tanner Stewart August 31, 2000, page charges will be voluntary for the first 10 David M. Rachal Jason A. Stine published pages only. All pages in excess of 10 will incur a Richard M. Rader Randy L. Stotler mandatory charge of $125 per page. Mike Rampey Diana B. Strickland Alan S. Rapp Steven S. Suk This policy was recommended by the GSA Publications Com- William M. Ratcliffe Biyai D. Suku-Ogbari mittee and approved by the GSA Council at its May 2000 Lily A. Ray Jeffrey J. Supplee meeting. The mandatory page charges are intended to serve as Cory M. Redman Dustin E. Sweet a mechanism to decrease the length of articles submitted, Thomas K. Reese Lindsay A. Szramek which should result in more papers published in each issue Christopher J. Regan Darren A. Szuch and papers published more rapidly. In this way the Bulletin Timothy P. Reilly Andrew W. Taylor can continue to publish diverse topics without incurring Erik S. Reinert Peter B. Taylor excess publishing costs. Kendra J. Remley Tiffany F. Tchakirides Kanya A. Rhedrick Elizabeth L. Tenpenny Noelle Richard Rena Thiagarajan AUGUST Kara A. Richardson David W. Thomas Shauna J. Riedel Samuel P. Thompson Bulletin and Geology Luis A. Rios Kelly R. Titkemeier Kathleen M. Roberts Darren L. Tollstrup Patricia E. Robinson Laurie L. Trevizo Highlights William C. Robinson Yasemin I. Tulu James B. Rondeau Kenzie J. Turner Visit Bulletin and Geology at www.geosociety.org. Eric L. Rothwell Anna K. Tye This online service is free for a limited time. Jenee L. Rowe Matthew J. Udovitsch Heather R. Roy Patrick G. Umphenour Richard J. Rudd Annemarie D. van Biemen Stacia D. Russo Dolores A. van der Kolk In August Bulletin Carolyn H. Ryder Isaac J. Vandergon A. Brady Sabelli Sarah E. VanGelder ◆ Isotopic provinciality of Joe Sadera Catherine E. Vaughan Tanaporn Sakulpitakphon Emily M. Von Bergen the Mojave Desert Cara M. Santelli Kristina M. Walker ◆ Volcanic hazards along Cindy L. Satterfield Michael C. Wall Stephan Schayen Michael J. Wallace the Mexico-Guatemala Rachel T. Schelble Matthew D. Walters border Kevin A. Schleh Brian W. Warner ◆ Nicholas C. Schmerr Dawn L. Wells Cosmogenic ages Brian P. Seneker Christine R. Wennen for the Last Glacial Michael D. Senglaub Laura J. Wilcox Maximum, Arctic Jeffery S. Shaner Jason E. Williams Canada Gary R. Shehane Mark A. Williams Joshua Shenker Kyle H. Willis Audrey F. Sherry Brant R. Wilson Sarah J. Shoemaker Nicholas A. Wojieck Lesley P. Short Jennifer M. Wolters In August Geology Karin W. Shultz Flavia L. Wood Renee C. Sietmann Sharon M. Woods Adrienne M. Sims Lynn R. Yarmey ◆ Ecology of extinctions Jonathan M. Skaggs Andrew A. Young Jack A. Skeahan Erin M. Young ◆ Ooze clues Michael K. Small Aimee M. Zipf ■ Eric G. Smith ◆ Climatic diaspora Jocelyn Smith Lauren A. Smith ◆ Early gas stations ◆ Sensing a remote volcano

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GSA TODAY, August 2000 35 Hypoxia in the Gulf of Mexico: Causes, Consequences, and Political Considerations

T.M. Kennedy* and T.W. Lyons, Department of Geological Sciences, University of Missouri, Columbia, MO 65211

Each year as the snows of the north- tle to the ocean floor, bacterial decay con- reflecting the expected lag between peak ern plains melt and crop-nourishing rains sumes oxygen faster than photosynthesis river discharge in the late winter or early fall on fields throughout the Mississippi can replace it. Under ordinary circum- spring and the productivity-linked con- River Basin, a nutrient-rich freshwater stances, oxygen depletions are short-lived sumption of oxygen. plume enters the northern Gulf of Mexico. because of natural downward mixing of In 1998, Congress passed the Harmful The resulting biological blooms and subse- water in contact with the oxygen-rich Algal Bloom and Hypoxia Research and quent decreases in dissolved oxygen are atmosphere. In some cases, however, den- Control Act, which allocates approxi- issues of great ecological concern. Fertilizer sity stratification inhibits mixing between mately $11 million over three years for use throughout the central United States fresh and saline waters. In the northern research and monitoring of hypoxia. In has been implicated in an ongoing politi- Gulf of Mexico, freshwater inputs from this context, a task force was established cal and scientific debate. However, the the Mississippi–Atchafalaya River Basin to assess the nature, causes, and conse- pace and mechanisms of corrective action cause such stratification. quences of Gulf hypoxia and to propose may be dictated more by economics and The combined influence of stratifica- strategies for controlling it. Since the post- corresponding political clout than by the tion and river-supplied nutrients in the ing of the initial integrated assessment, severity of habitat perturbation. Gulf is evident in annual measurements of various special interest groups have With the increasing urbanization of the hypoxic zone’s areal extent (Fig. 1B). responded and remain close to the discus- our coastal regions and agricultural expan- The smallest recorded hypoxic zone, for sion (their comments and the assessment sion in major river basins, oxygen defi- example, occurred in 1988, a drought year. are available at www.nos.noaa.gov/ ciencies are becoming a major environ- By contrast, a year of severe flooding, products/pubs_hypox.html, June 2000). mental problem in coastal waters 1993, showed an increase in areal extent Involvement of these groups has centered throughout the world. These deficiencies of >50% beyond the previous year. The on several points of heated controversy, are referred to as hypoxia when dissolved hypoxic zone has remained large since beginning with the primary cause of oxygen levels drop below 2 mg/L relative 1993, culminating with the largest eutrophication. Mass balance analysis of to ~7 mg/L for nonhypoxic times. Low recorded zone spanning some 20,000 km2 inputs and outputs within the basin indi- oxygen concentrations occur naturally in in the summer of 1999. The seasonal cates that fertilizer is responsible for 50% stratified marine settings such as the Black trends for Gulf hypoxia further link the of the input of all nitrogen to the waters Sea. In recent years, however, increased stratification and nutrient enrichments to of the Mississippi–Atchafalaya River Basin, nutrient runoff from the continents has riverine contributions (Fig. 1C). Depletion which makes it the primary source of Gulf exacerbated natural hypoxia and has of oxygen begins in the spring and reaches nitrogen enrichment. Less significant con- caused hypoxia and anoxia at previously its highest point in the mid-summer, tributors include soil erosion, manure, well-oxygenated sites. Seasonal depletions in oxygen on the Louisiana continental shelf extend westward from the Mississippi Delta and are the most extensive example of marine hypoxia in the United States (Fig. 1A). Like any occurrence of hypoxia, a number of complex processes contribute to its development, the most significant of these being eutrophication and stratification of freshwater over denser saline water. Eutrophication is an enrichment in dissolved nutrients (especially nitrogen and phosphorus) that promotes increased primary production. As the abundant phytoplankton die and set-

* Present address: Yale Law School, New Haven, CT 06520.

Figure 1. Temporal trends. A. Frequency of hypoxia occurrence, 1985–1997, based on annual measurements of areal extent. B. Areal extent of hypoxic zone based on annual measurements taken in mid-summer. C. Seasonal variability of bottom-water oxygen at a single station during hypoxic interval of 1993. Data in red indicate hypoxia. Figures modified from Rabalais et al. (1999, Topic no. 1, Gulf of Mexico Assessment; www.nos.noaa.gov/products/ pubs_hypox.html.

36 GSA TODAY, August 2000 Figure 2. Total market value of crops, fertilizer, and seafood for 1997 compared to the estimated total cost of leading proposal for reducing nutrient loads to Gulf of Mexico. Data from U.S. Depart- ment of Agriculture, National Oceanic and Atmospheric Administration, and Doering et al. (1999, Topic no. 6, Gulf of Mexico Assessment; www.nos.noaa.gov/products/pubs_hypox.html).

legumes, atmospheric deposition, and municipal and industrial waste. Neverthe- less, the American Farm Bureau and the Fertilizer Institute contend that more research is needed to unambiguously (i.e., quantitatively) link fertilizer to nitrogen runoff into the Mississippi River. The Fer- tilizer Institute has downplayed the significance of contributions from fertilizer by stressing, among other factors, increased freshwater flow and the resulting relation- ship between water-column stratification and hypoxia. A second flurry of controversy is clus- tered around the effect of hypoxia. When water-quality models predict that reducing lion for the top three buyers of fertilizer in oxygen becomes scarce, faunal communi- nutrient loads by 20%–30% should the region most likely to be impacted by ties migrate to areas of higher oxygen or, increase dissolved bottom-water oxygen Gulf hypoxia reduction policy (Illinois, in the case of many less mobile organisms, by 15%–50%. Reduction of nutrients by Iowa, and Missouri). This figure stands in perish. This idea of a “dead zone” has 30%–50% could bring about a 20%–75% clear contrast to the $312 million value of attracted the popular press to the issue of increase in oxygen. To make such reduc- Louisiana seafood landings in 1997 (Fig. hypoxia with a focus typically on the tions, researchers recommend multiple 2). Even when compared only to fertilizer potential damage to the fishing industry. strategies, such as construction of wet- expenditures in Illinois, Iowa, and Mis- Despite this focus, the sparse existing data lands in the Mississippi River Basin, reduc- souri, or to the value of crops in only suggest that yearly yields in the regional tion of fertilizer application, use of alter- those counties bordering the Mississippi fish and shrimp catch have not been eco- native cropping systems, and reduction of River, the Gulf seafood landings are minor. nomically affected in any way directly feedlot runoff. Any combination of these From a purely economic standpoint, the attributable to hypoxia because these strategies would be costly, and models for cash value of these landings fails to justify organisms are able to escape from areas of such a complex system are inherently the $2.08 billion total cost of the proposed low oxygen. Shrimpers maintain their uncertain. Nevertheless, research summa- solutions. yields by shifting their efforts to the mar- rized in the draft of the integrated assess- Differences in the value of crops and gins of the hypoxic zone where migrating ment indicates that the most cost-effective landings are reflected in disparities in rep- shrimp are in abundance. In fact, Richard- means of reducing nutrient loads by 20% resentation and, ultimately, in relative lob- son and Jørgensen (1996, Eutrophication would be a combination of a 20% reduc- bying strength within the political arena. in coastal marine systems, Coastal and tion in fertilizer application and construc- For example, the American Farm Bureau Estuarine Studies, 52, American Geophysi- tion of five million acres of wetlands. represents nearly five million families in cal Union, Washington, D.C.) in their gen- According to the Fertilizer Institute, this 50 states and Puerto Rico (www.fb.com, eral survey of coastal hypoxia noted that proposal is too expensive in light of the June 2000). By contrast, the largest organi- slightly reduced oxygen can be a boon to uncertainty surrounding economic bene- zation representing Louisiana fishermen the local fishery by focusing the fish (and, fits to fisheries and is inadequately justi- on environmental issues has a member- by inference, shrimp) toward the bound- fied by existing scientific data. Institute ship of about 350 fishermen, and annual ary of the oxygen-deficient region. officials specifically noted in their dues are just $100. Run solely by volun- This emphasis on the fishing industry response to the proposed remediation teers, the Gulf Coast Commercial Fisher- diverts attention away from potentially strategies that, “...the recommendations men’s Coalition cannot engage in lobby- more calamitous consequences. Annual would relegate farmers to economic ing activities because of its status as a ecological perturbations in the Gulf could poverty, and the benefit of this policy is a nonprofit organization. have catastrophic long-term impacts by complete unknown.” These inequalities have affected preventing the reestablishment of prehy- Inherent polarity in the scientific hypoxia policy discussions. The American poxia marine communities. Harmful algal interpretations is not the only factor deter- Farm Bureau, the Fertilizer Institute, and blooms are one example of an ecosystem mining what solutions, if any, will be other agribusiness interest groups have imbalance associated with the same nutri- implemented. Economically speaking, aggressively represented their constituents ent fluxes that cause hypoxia. Current pol- agribusiness and the Gulf fishing industry throughout the discussions. These well- icy discussions have alluded to but have stand at opposite extremes in this debate. funded and well-staffed organizations never explicitly addressed the essential Agribusiness is a staple of the American have attended formal meetings, issued question: What magnitude of habitat economy, having contributed $98 billion press releases, made extensive public com- modification and loss of noncommercial through crop sales in 1997 (www.usda. ments, and have lobbied at state and fed- species is acceptable in the absence of gov/nass, June 2000). By contrast, the eral levels. According to the Center for immediate or even long-term dire conse- value of commercial fishing in the entire Responsive Politics, nontobacco agricul- quences to the fishing industry? Gulf of Mexico for 1997 was only $762 tural interest groups reported lobbying Proposed solutions are also controver- million (www.st.nmfs.gov, June 2000). sial. As the integrated assessment notes, Total crop sales in 1997 exceeded $15 bil- Hypoxia continued on p. 38

GSA TODAY, August 2000 37 CALENDAR

Only new or changed information is 2001 Meetings Turkey. Information: Bahtiyar Unver, Co-Chair- published in GSA Today. A complete listing man, Organizing Committee, Department of January Mining Engineering, Hacettepe University, can be found in the Calendar section on January 12–16, International Conference on the Internet: www.geosociety.org. Beytepe Ankara, 06532 Turkey, 90-312-297- the Geology of Oman, Muscat, Sultanate of 7696, fax 90-312-299-2155, unver@ Oman. Information: Organizing Committee, 2000 Meetings hacettepe.edu.tr, http://www.mining-eng.org.tr. International Conference on the Geology of (Abstract deadline: October 31, 2000.) October Oman, Directorate General of Minerals, Ministry July October 22–24, American Society for Test- of Commerce and Industry, P.O. Box 550, Mus- July 7–10, American Rock Mechanics Asso- ing and Materials Committee E29 on Par- cat 113, Sultanate of Oman, geoconfoman@mpi. ciation’s DC Rocks 2001, 38th U.S. Rock ticle and Spray Characterization, Orlando, unibe.ch, www.geoconfoman.unibe.ch. (Abstract Mechanics Symposium, Washington, D.C. Florida. Information: Jim Olshefsky, ASTM, (610) and registration deadline: September 1, 2000.) Information: John Tinucci, Technical Program 832-9714, fax 610-832-9555, [email protected]. May Chair, PanTechnica Corporation, (952) November May 27–30, St. John’s 2001, Geological 937-5879, fax 952-949-4364, jtinucci@ November 9–12, Association for Women Association of Canada–Mineralogical Asso- pantechnica.com, www.armarocks.org. Geoscientists Fall Board of Directors Meet- ciation of Canada 2001 Joint Annual Meet- (Abstract deadline: October 1, 2000.) ing, Reno, Nevada. Information: AWG, P.O. Box ing, St. John’s, Newfoundland, Canada. Informa- August 280, Broomfield, CO 80038-0280, office@ tion: St. John’s 2001, c/o Department of Mines August 31–September 12, Field Excursion to awg.org. and Energy, St. John’s, NF A1B 4J6, Canada, (709) 729-2301, fax 709-729-3493, dmp@ the Skaergaard Intrusion, Kangerdlugssuaq, November 13–14, American Society for Test- zeppo.geosurv.gov.nf.ca, www.geosurv.gov.nf. East Greenland. Information: Jens C. Andersen, ing and Materials Committee E20 on Tem- ca/stjohns2001. Camborne School of Mines, University of Exeter, perature Measurement, Orlando, Florida. Redruth, Cornwall, UK, 44-1209-714866, fax Felicia Quinzi, ASTM, (610) 832-9738, fax 610- June 44-1209-716977, [email protected], 832-9555, [email protected]. June 19–22, 17th International Mining www.ex.ac.uk/CSM/news/confs.htm. (Deposit Congress and Exhibition of Turkey, Ankara, due by September 1, 2000.)

Hypoxia continued from p. 37 CLASSIFIED ADVERTISING expenditures of nearly $52 million in 1998 (www.opensecrets.org, June 2000). Published on the 1st of the month of issue. Ads (or can- (in cooperation with other faculty); training and supervision cellations) must reach the GSA Advertising office one of graduate and undergraduate teaching assistants; over- The American Farm Bureau alone month prior. Contact Advertising Department (303) sight of laboratory specimens and demonstration equip- reported spending over $4.5 million in 447-2020, 1-800-472-1988, fax 303-447-1133, or e-mail: ment; field trip planning and logistics; and oversight of that year. The fishing industry, by con- [email protected]. Please include complete department rock preparation, field, and/or computer equip- address, phone number, and e-mail address with all ment. This person will also teach one course each year trast, has been conspicuously absent correspondence. and may supervise student research. We seek a dynamic individual with a high level of intel- from nearly all aspects of the policy pro- Per line lectual curiosity and a demonstrated interest and ability in cess. Per Line for each undergraduate education. While the field of specialization for addt'l month Ultimately, substantive corrective is open, we encourage applications from individuals Classification 1st month (same ad) action will be slow in coming within the whose expertise complements existing department muddled political context of Gulf Situations Wanted $1.75 $1.40 strengths in metamorphic petrology and tectonics, paleon- Positions Open $6.50 $5.50 tology, sedimentology and structural geology. A Ph.D. is hypoxia. The fishing industry lacks the Consultants $6.50 $5.50 required at the time of appointment. resources and perhaps motivation to gal- Services & Supplies $6.50 $5.50 Applications should include curriculum vitae, a descrip- vanize public and congressional opinion Opportunities for Students tion of teaching philosophy and experience, and letters first 25 lines $0.00 $2.35 from at least three professional references. Send the and thus may be ineffective as a politi- additional lines $1.35 $2.35 applications to: Lab Coordinator Search, Professor M. L. cal catalyst. While the details of the sci- Code number: $2.75 extra Crawford, Department of Geology, Bryn Mawr College, entific arguments warrant further study 101 N. Merion Ave., Bryn Mawr, PA 19010-2899. Review Agencies and organizations may submit purchase order or of applications will begin Sept. 1, and the position will and debate, the preponderance of scien- payment with copy. Individuals must send prepayment remain open until filled. E-mail applications are also tific research has unambiguously identi- with copy. To estimate cost, count 54 characters per line, accepted—mail to [email protected]. fied agriculture as the single greatest including all punctuation and blank spaces. Actual cost Bryn Mawr College is a liberal arts college for women may differ if you use capitals, centered copy, or special with coeducational graduate programs in sciences, some contributor to Gulf hypoxia. Ultimately, characters. humanities and social work. The College provides a rigor- the issue of fertilizer-linked, seasonal ous education in the context of a diverse and pluralistic oxygen depletion in the Gulf of Mexico To answer coded ads, use this address: Code # ----, scholarly community and participates in consortial pro- GSA Advertising Dept., P.O. Box 9140, Boulder, CO grams with the University of Pennsylvania, Haverford and speaks directly to the level of environ- 80301-9140. All coded mail will be forwarded within Swarthmore Colleges. Bryn Mawr College is an equal mental perturbation that may be toler- 24 hours of arrival at GSA Today office. opportunity, affirmative action employer. Members of ated in the absence of catastrophic eco- underrepresented groups are especially encouraged to apply. For more information about the position, the nomic loss and imminent threat to Department and the College, visit www.brynmawr.edu/ public health—particularly given the Positions Open Acads/Geo. estimated cost of correction. Like all LABORATORY COORDINATOR/LECTURER CENTRAL MICHIGAN UNIVERSITY nonpoint-source pollution in which the DEPARTMENT OF GEOLOGY MINERALOGY/PETROLOGY BRYN MAWR COLLEGE ASSISTANT PROFESSOR TENURE-TRACK POSITION effect is spatially decoupled from the The Department of Geology at Bryn Mawr College invites cause, and in which scientific details are The Department of Geology invites applications for an applications for a coordinator of introductory laboratories entry-level tenure-track position beginning in August 2001. worked and reworked by multiple beginning January 2001. This is a full-time (9-month), con- We seek a person with the following qualifications: 1) tinuing, non-tenure-track position. Initial appointment will Ph.D. in geology with a specialty in mineralogy or petrol- groups, it will be a challenge to con- be for three years. Primary responsibilities will include: vince Congress and the public that ogy, 2) demonstrated excellence in teaching is preferred, design and supervision of laboratories for introductory 3) commitment to field-based studies, 4) demonstrated action is necessary. ■ courses in physical, historical, and environmental geology commitment to high-quality undergraduate research, 5)

38 GSA TODAY, August 2000 excellent communication skills. The successful applicant to recruit a geoscientist with the potential to develop an will be required to 1) teach mineralogy, introductory geol- innovative research programme on the sedimentary ogy, and courses in his or her specialty, 2) develop a suc- record using modern quantitative methods. Development cessful research program, and 3) develop and submit of South Pacific regional geologic interests, either onshore external grant proposals. or offshore, and a strong commitment to fieldwork is The Department of Geology currently has eight full- expected. Applicants should hold a Ph.D. degree or equiv- time faculty and 40 to 60 undergraduate majors. Teaching alent in an appropriate discipline and have postdoctoral loads will range from 9 to 12 contact hours per 15-week research experience. A commitment to high quality teach- semester. The department has a strong record of incorpo- ing at undergraduate and graduate level, and a willing- rating research into the undergraduate curriculum. For ness to contribute to field courses will be required. The more information, visit our departmental web site at appointee will also be expected to conduct research, to www.cst.cmich.edu/units/gel/. obtain external research funding and to supervise post- Central Michigan University enrolls approximately graduate students at the M.Sc. and Ph.D. levels. 18,000 students (87% undergraduate), and is located in The University's World Wide Web address is www. the heart of the Michigan Basin. The department has mod- canterbury.ac.nz. Academic enquiries only may be made ern and well-equipped facilities which include: automated to Professor J.W. Cole, fax 64-3-3642-769 or e-mail: ARL-SEMQ electron microprobe, Phillips XRD, VG-PQ2 [email protected]. ICP-MS, fluid inclusion lab, rock and mineral sample Appointment enquiries should be made to hr@regy. preparation facilities, a networked IBM and Mac computer canterbury.ac.nz. lab, geophysical instruments, in-house GIS, access to Applications, quoting Position No GS126, close on 30 other modern GIS and GPS systems, and two departmen- September 2000 with the Human Resources Manager, tal vans. In addition, the department has access to other University of Canterbury, Private Bag 4800, Christchurch, computing and analytical facilities on campus and at New Zealand. nearby universities. The University has a policy of equality of opportunity in Interested persons should send: 1) a resume, 2) state- employment. ments of teaching philosophy, research interests, and vision for undergraduate education, 3) unofficial tran- FACULTY POSITION IN BIOGEOSCIENCE scripts, and 4) three letters of reference to: DEPARTMENT OF GEOLOGY Mineralogist/Petrologist Search Committee, Department of UNIVERSITY OF MARYLAND, COLLEGE PARK Geology, Central Michigan University, Mt. Pleasant, MI The Department of Geology at UM is searching for a 48859. tenure-track faculty member who has made fundamental All applications and materials must be received by contributions in biogeoscience. We seek an outstanding October 6, 2000. scientist with research interests in the interdisciplinary CMU, an AA/EO institution, is strongly and actively com- field of geomicrobiology/mineralogy, or a closely related mitted to increasing diversity and providing equal opportu- field. Research strengths in the Department of Geology nity within its community. CMU does not discriminate in are in the broad areas of mineralogy, petrology and geo- employment against any person based on age, color, dis- chemistry, in particular, crustal evolution and granites and ability, gender, familial status, height, marital status, associated mineralization; structural geology and tecton- national origin, political persuasion, race, religion, sexual ics; hydrological processes and integration of geomorphol- orientation, veteran status, or weight (see www.cmich.edu/ ogy, hydrology and ecology to understand surface envi- aaeo.html). ronments; and, isotope geochemistry in support of these BOOKS: Geology, Paleontology, History of Geology. areas, and in mantle geochemistry, meteoritics, Used, out-of-print, and rare. Free catalog. Patricia L. GEOLOGIST/HYDROGEOLOGIST geochronology, carbonate diagenesis, sediment cycling, Daniel, BS, MS, Geology. 618 W. Maple, Indepen- OGDEN ENVIRONMENTAL AND ENERGY SERVICES stratigraphy and paleoclimate studies. The Department of dence, KS 67301, ph: (316) 331-0725, fax: (316) 331- Ogden Environmental and Energy Services has the need Geology encourages interdisciplinary approaches to the 0785, email: [email protected], website: for geologists/hydrogeologists in our San Rafael office. study of the Earth and participates in the Earth System http://users.hit.net/~pldaniel. MS geology/hydrogeology, CA registered geologist/hydro- Science Interdisciplinary Center, which is a new Center geologist, 8–10 yrs professional exp. in groundwater eval- formed by the University of Maryland and NASA/Goddard uations, site investigations, site remediation & project Space Flight Center to advance fundamental knowledge Opportunities for Students mgmt required. Prefer candidates with govt & commerical about the earth system through preeminent research and client exp. Please send resume to OEES, 980 Lincoln teaching programs. Graduate Student Support Opportunities in Earth Sci- Avenue, Ste. 200, San Rafael, CA 94901; fax (415) 454- The Department expects to fill this position by Summer ences, Lehigh University—The Department of Earth and 1001 or [email protected]. EOE/AA. 2001. Salary will be commensurate with experience. The Environmental Sciences of Lehigh University has Graduate appointee is expected to develop and maintain an active, Student Fellowships for highly qualified individuals. The ASSISTANT PROFESSOR externally-funded research program, to direct graduate department has active research programs in tectonic stud- SOUTHERN METHODIST UNIVERSITY students, and to participate fully in teaching at the gradu- ies (geochronology, stable-isotope geochemisty, low-tem- The Department of Geological Sciences at Southern ate and undergraduate levels, including courses in the perature geochemistry, seismology, high-resolution geo- Methodist University invites applications for a tenure-track introductory non-major program. physics, structural geology, paleomagnetism) and surficial faculty position in the broad areas of surficial processes or The University of Maryland is an affirmative processes (low-temperature geochemistry, fluvial and tec- geodynamics. We seek creative applicants with an excel- action/equal employment opportunity employer. Applica- tonic geomorphology, glacial geology, hydrology, and lim- lent understanding of fundamental physical principles and tions should be submitted by September 29, 2000, for nology). Please contact Prof. D. Morris, Dept. of Earth and processes, and a demonstrated ability to apply that under- best consideration, and should be submitted to: Chair, Environmental Sciences ([email protected]) or see our standing in a quantitative manner to important problems in Search Committee, Department of Geology, University of Web page for more details (www.ees.lehigh.edu). the earth sciences. The department seeks an individual Maryland, College Park, MD 20742, USA (electronic sub- who will complement existing strengths in one or more of missions to: [email protected]). Persons interested Graduate Study in Marine Sedimentology. The LSU the following areas: geochemistry, petrology/tectonics, in being considered for this position should provide a Department of Oceanography and Coastal Sciences is geophysics, planetary dynamics, terrestrial paleoecology. statement describing research and teaching interests, seeking applicants for graduate study in marine sedimen- We anticipate making the appointment at the assistant indicating how s/he envisions contributing to the Depart- tology. Potential research topics include sedimentology of professor level with the appointment to begin no later than ment's research and teaching activities, and a current cur- modern deltas, radioisotope geochronology of recent Fall, 2001. Applicants are required to have a PhD by the riculum vitae. Applicants should arrange to have a mini- deposits, and impacts of combined event sedimentation beginning of the Fall 2001 semester. The successful can- mum of four letters of recommendation sent directly to the and bioturbation on the sediment record. We are seeking didate will be expected to teach at the undergraduate and Chair of the Search Committee before September 29, a highly qualified individual with demonstrated capacity for graduate levels, supervise graduate research, and estab- 2000. The Search Committee encourages applicants to independent work. Qualified applicants will be considered lish an externally funded research program in his or her submit copies of up to two recent publications in support for a 4-year fellowship of $16,000 per year. Additional field of expertise. The committee will begin its review of of their candidacy. funding will be sought for additional years. Students seek- the applications on or about November 1, 2000. To ensure ing either the PhD or MS/PhD in geological oceanography full consideration, the application should be postmarked should apply by completing and submitting the graduate by November 1, 2000. Candidates should submit their cur- program preapplication (found at www.oceanography. riculum vitae, names and addresses of three references, Services & Supplies lsu.edu/application.html) for a start date as soon as and a written statement of teaching and research interests August 2000. For questions or to request a mailed preap- to: Dr. Lee McAlester, Chair, Department of Geological OLD STOCK & BOND CERTIFICATES WANTED! Buy & plication, contact Dr. Larry Rouse, Graduate Advisor, Sciences, P.O. Box 0395, Southern Methodist University, sell all topics especially mining. Contact Norrico, Box ([email protected], 225-388-2953) or Dr. Sam Bentley Dallas, Texas 75275-0395. Email: [email protected] 660077, Flushing, NY 11366; (718) 380-4009; norrico@ ([email protected], 225-388-2954), Coastal Studies Institute, and website: www.geology.smu.edu. SMU is an Affirma- compuserve.com. Howe-Russell Geosciences Complex, Louisiana State tive Action/Equal Opportunity/Title IX Employer. University, Baton Rouge, Louisiana 70803, USA. ■ RECENT, RARE, AND OUT-OF-PRINT BOOKS. Find our UNIVERSITY OF CANTERBURY on-line catalog at home.earthlink.net/~msbooks for books LECTURER/SENIOR LECTURER IN on Geology, Mining History, USGS, and Western Ameri- GEOLOGICAL SCIENCES cana; e-mail: [email protected]. For free printed cat- Applications are invited for a continuing (tenured) full-time alogs send your request and area(s) of interest to MS position as LECTURER or SENIOR LECTURER in the Book and Mineral Company, P.O. Box 6774, Lake DEPARTMENT OF GEOLOGICAL SCIENCES. We wish Charles, LA 70606-6774.

GSA TODAY, August 2000 39 GSA Annual Meeting and Exposition

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