Vol. 9, No. 2 February 1999

INSIDE GSA TODAY • 1999 Section Meetings Rocky Mountain, p. 17 A Publication of the Geological Society of America North-Central, p. 23

Hypercalcification: Paleontology Links Plate Tectonics and Geochemistry to Sedimentology Steven M. Stanley Lawrence A. Hardie Morton K. Blaustein Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, MD 21218

ABSTRACT During the Phanerozoic Eon, the mineralogies of nonskeletal marine cements and oolites have oscillated on a 100–200 m.y. scale between aragonite ± high-Mg calcite (aragonite seas) and low-Mg calcite (calcite seas). Oscilla- tions in the carbonate mineralogy of dominant reef-building and sediment- producing organisms are in harmony with the oscillations for nonskeletal carbonates. These oscillations, together with synchronous oscillations in the mineralogy of marine potash evapor- ites, can be explained by secular varia- tion in the Mg/Ca ratio of seawater An aragonitic brain coral, Diploria strigosa, of late Pleistocene age, from the Cockburn Town fossil coral reef, San Salvador Island, Bahamas. This reef formed during the most driven by changes in the spreading rates recent interval of aragontie seas. Photo by Al Curran, Smith College. along midocean ridges. The temporal patterns for biocalcification have come to light through a focus on (1) simple taxa that exert relatively weak control over the milieu in which they secrete their skeletons, and (2) taxa that hyper- calcify—i.e., secrete massive skeletons or are exceptionally productive, for example, in forming voluminous chalk deposits. Most major reef-building and sediment-producing taxa belong to both of these categories. It appears that the Mg/Ca ratio of seawater has not only controlled Phanerozoic oscillations in hypercalcification by simple taxa, such as calcareous nannoplankton, sponges, and bryozoans, but has strongly influ- enced their skeletal evolution.

Figure 1. Effect of changes in the rate of seafloor spreading (ocean crust production) on global sea INTRODUCTION level, the flux of MOR hydrothermal brine, and the chemistry of seawater as predicted by Spencer and Following an era of specialization Hardie (1990) and Hardie (1996). A—high-spreading-rate conditions; B—low-spreading-rate conditions. in the earth sciences, many conceptual Red arrows—MOR brine paths (thicknesses of the arrows are proportional to the brine flux but not to scale). Gray arrows proportional to spreading rates (not to scale). advances are now emerging through inter- disciplinary research. The flow of earth materials through chemical cycles, for example, links diverse scientific fields, as mineralogy of dominant reef-building and In a seminal study of oolites and early do sequences of causal relationships that sediment-producing organisms can be marine cements, Sandberg (1983) showed connect noncyclical physical, chemical, linked to shifts in seawater chemistry that nonskeletal carbonate precipitation and biological phenomena. We have con- controlled by changes in global spreading cluded that Phanerozoic oscillations in the rates along mid-ocean ridges (Fig. 1). Hypercalcification continued on p. 2 IN THIS ISSUE GSA TODAY February Vol. 9, No. 2 1999 Hypercalcification: Paleontology Links Washington Report ...... 12 Plate tectonics and Geochemistry to GSA On the Web ...... 12 GSA TODAY (ISSN 1052-5173) is published monthly Sedimentology ...... 1 by The Geological Society of America, Inc., with offices at 3300 GSAF Update ...... 14 Penrose Place, Boulder, Colorado. 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Nonmembers & Institutions: Free with paid subscription to both GSA Bulletin and Geology, otherwise $50 for U.S., Canada, and Mexico; $60 else- Hypercalcification continued from p. 1 low-magnesium calcite to precipitate where. Contact Subscription Services. Single copies may be requested from Publication Sales. Also available on an instead of aragonite. annual CD-ROM, (together with GSA Bulletin, Geology, GSA in Phanerozoic seas has oscillated between It has long been recognized that Data Repository, and an Electronic Retrospective Index to aragonite and calcite (Fig. 2). It has been changes in the Mg/Ca ratio of seawater journal articles from 1972); $89 to GSA Members, others call GSA Subscription Services for prices and details. Claims: widely held that relatively low levels of can dictate whether calcite or aragonite For nonreceipt or for damaged copies, members contact atmospheric pCO2 have produced “arago- precipitates from seawater. Experiments Membership Services; all others contact Subscription Ser- nite seas,” while relatively high levels have demonstrating this relationship (Fücht- vices. Claims are honored for one year; please allow suffi- cient delivery time for overseas copies, up to six months. produced “calcite seas” (Wilkinson and bauer and Hardie, 1976, 1980), which are Algeo, 1989; Mackenzie and Morse, 1992). in accord with data for natural saline lakes STAFF: Prepared from contributions from the GSA staff and membership. Calculations using the computer program (Müller et al., 1972), indicate that, at 25 °C Executive Director: Donald M. Davidson, Jr. PHRQPITZ (Plummer et al., 1988) show, and present seawater ionic strength and Science Editors: Suzanne M. Kay, Department of however, that pCO2 is not a viable control atmospheric pCO2, a ratio for Mg/Ca of Geological Sciences, Cornell University, Ithaca, NY 14853; Molly F. Miller, Department of Geology, Box 117-B, Vanderbilt (Stanley and Hardie, 1998). Seawater of ~2 separates a regime of calcite precipita- University, Nashville, TN 37235 modern composition would be supersatu- tion from a regime of aragonite ± high-Mg Forum Editor: Bruce F. Molnia, U.S. Geological Survey, rated with respect to calcite and undersat- calcite precipitation (Fig. 3). MS 917, National Center, Reston, VA 22092 Director of Publications: Peggy S. Lehr urated with respect to aragonite only for Spencer and Hardie (1990) introduced Managing Editor: Faith Rogers a narrow range of pCO2, within which all a quantitative model for calculating the Assistant Editor: Vanessa Carney Production Manager: Jon Olsen values are more than an order of magni- chemistry of ancient seawater based on Production Editor and Coordinator: Joan E. Manly tude greater than that of the present—a the premise that the composition of mod- Graphics Production: Joan E. Manly, Leatha L. Flowers level almost certainly not attained during ern seawater results primarily from the ADVERTISING: Classifieds and display: contact Ann the Cretaceous interval of calcite seas mixing of average riverwater (a Ca-HCO3 Crawford, (303) 447-2020; fax 303-447-1133; acrawford@ (Berner, 1994). In fact, such high levels water) and mid-ocean ridge (MOR) geosociety.org. of pCO2 would cause aragonitic shells of hydrothermal brines (Na-Ca-Cl waters). Issues of this publication are available as electronic Acrobat organisms to begin dissolving immediately This model predicts that relatively minor files for free download from GSA’s Web Site, http://www. geosociety.org. They can be viewed and printed on various after their secretion. Furthermore, experi- changes in the flux of MOR hydrothermal personal computer operating systems: MSDOS, MSWin- ments show that for present-day seawater brines would change the Mg/Ca, Na/K, dows, Macintosh, and Unix, using the appropriate Acrobat at 25 °C (Mg/Ca mole ratio = 5.17), raising and Cl/SO ratios in seawater enough to reader. Readers are available, free, from Adobe Corporation: 4 –4.5 –1.0 http://www.adobe.com/acrobat/readstep.html. pCO2 from 10 to 10 atm simply low- drastically alter the primary mineralogy This publication is included on GSA’s annual ers the MgCO3 content of precipitated cal- of nonskeletal marine carbonates and CD-ROM, GSA Journals on Compact Disc. cite from 12 to 7 mol% (Burton and Wal- evaporites. Call GSA Publication Sales for details. 50% Total Recoverd Fiber ter, 1991); it does not cause Printed in U.S.A. using pure soy inks. 10% Postconsumer

2 GSA TODAY, February 1999 CALL FOR NOMINATIONS POSITION AVAILABLE History of EXECUTIVE DIRECTOR Geology Award The Geological Society of America (GSA) is seeking an individual to assume the duties of Executive Director as early as June 1, 1999. The selected individual will: The History of Geology Award is pre- • Work with the Executive Committee and Council of GSA to implement a newly sented annually to an individual who adopted Strategic Plan. Work closely with GSA Foundation Board and staff to coordi- has made contributions of fundamental nate and promote the directions and policies of the GSA Council. importance to our understanding of • Maintain collaborative relationships with representatives of other national and interna- the history of the geological sciences. tional geoscience societies and organizations and actively pursue joint ventures that Outstanding contributions might enhance the financial and scholarly status of the Society. include publication of papers or books • Lead the GSA Headquarters staff of 65 persons. Articulate the vision and mission of the of distinction that contribute new and Society to staff and members through teamwork and collaborative efforts. Staff activi- profound insight into the history of ties include membership services; meetings; publications; education, public policy, and geology (based either on original outreach; marketing and strategic communications; financial services; and information research or on a synthesis of existing technology. knowledge); discovery of and making The new Director will work at the GSA headquarters in Boulder, Colorado, and will hold a available to scholars of rare resource position with competitive compensation and benefits. materials; providing comprehensive bibliographic surveys; editing a themat- ically integrated collection of articles; REQUIREMENTS organizing meetings and symposia that • Provide leadership to diverse groups such as committees, associated societies, staff, and generate interest in the history of geol- volunteers through collaborative teamwork. ogy; innovative research into original • Commitment to strong interpersonal communication among and between staff, mem- sources; creative interpretations of data; bers, and volunteers. Proven record of motivating staff to develop new sources of rev- translations of key materials; and enue and to use technology to improve efficiencies. exceptional services to the GSA History • Master’s degree in geosciences; Ph.D. preferred. Extensive management experience of Geology Division. and achievements in the areas of accrual budgeting, financial planning and invest- ments, and personnel management. Additional preparation in education, marketing, To nominate a deserving individual, and/or business management encouraged. send a letter of nomination that • Commitment to geoscience research, public outreach and education programs, and describes the contributions that war- scholarly publishing. rant the award, along with supporting • Familiarity with marketing and public relations. materials, including the candidate’s • Demonstrated familiarity with the geoscience community and GSA programs. curriculum vitae to the chair of the award committee, Gerard V. Middle- Submit a resume, the names and addresses of three references, and a letter describing ton, Dept. of Geology, McMaster your interest in the position to: University, 1280 West Main, Hamilton, Executive Director Search Committee ON L8S 4M1, Canada (middleto@ The Geological Society of America mcmaster.ca; fax 905-522-3141). All P.O. Box 9140 nominations are valid for three years. Boulder, CO 80301-9140 Nomination deadline: April 1, 1999. The deadline for applications or nominations is March 15, 1999.

Mid-ocean ridges act as huge rock- first-order sea-level curves as a proxy for Na-Mg-K-Cl-SO4 brines, respectively, fluid ion exchange systems for Ca2+ and the record of ocean crust production dur- which lie on either side of a fundamental 2+ 2+ Mg , Ca being released to the fluid and ing the Phanerozoic Eon, Hardie (1996) chemical divide, the “CaSO4 divide” Mg2+ being consumed by the rock in the employed the Spencer-Hardie model to (Hardie and Eugster, 1970). Because both 2+ 2– conversion of oceanic basalts to green- predict the mineralogies of nonskeletal Mg and SO4 are extracted from seawa- stones and amphibolites by interaction marine carbonate ooids and cements as a ter at mid-ocean ridges, whereas Ca2+ and with hot seawater (Fig. 1). Low spreading function of secular changes in the Mg/Ca K+ are released, MOR hydrothermal brines rates (= low hydrothermal brine fluxes; ratio of seawater. The results are in close are of the calcium chloride type. There- Baker et al., 1995) should lead to elevated agreement with Sandberg’s (1983) periods fore, during periods of high spreading Mg/Ca mole ratios in seawater of the open of aragonite seas and calcite seas, as shown rates, the elevated fluxes of MOR brine oceans; if this ratio rose above ~2 for in Figure 2 (see also Hardie, 1996, Fig. 5). will drive seawater toward a calcium chlo- warm surface seawater, then aragonite ± Potash evaporites in the geological ride composition that on evaporative con- high-Mg calcite would precipitate instead record fall into two main chemical groups: centration would produce KCl evaporites. of low-Mg calcite (Fig. 2), as occurs in (1) KCl evaporites characterized by potas- On the other hand, low spreading rates today’s oceans. Conversely, high spreading sium chloride salts such as sylvite (KCl) would push seawater toward MgSO4- rates (= high hydrothermal brine fluxes; and an absence of magnesium sulfate salts, enriched composition and precipitation Baker et al., 1995) should lower the and (2) MgSO4 evaporites characterized by of MgSO4-type evaporites. Calculations Mg/Ca mole ratio in seawater; if this ratio magnesium sulfate salts such as kieserite based on the Spencer-Hardie model pre- dropped below ~2, then low-Mg calcite (MgSO4 ·H2O) (Hardie, 1996). These two dict that KCl evaporites should have pre- would precipitate instead of aragonite ± evaporite types precipitate from two very cipitated from calcite seas and MgSO4 high-Mg calcite (as predicted, for example, different parent brines, Na-Ca-Mg-K-Cl for the Cretaceous Period; Fig. 2). Using brines (“calcium chloride” brines) and Hypercalcification continued on p. 4

GSA TODAY, February 1999 3 Hypercalcification continued from p. 3 dominant mineralogy of marine biocalci- tigate the effects of seawater chemistry fiers. Although such a trend has not been on biocalcification (Stanley and Hardie, evaporites from aragonite seas. The rock apparent to more recent workers (Lowen- 1998). First, we focused on what we call record confirms this correspondence stam and Weiner, 1989, p. 237), Wilkin- hypercalcifying tropical taxa. Forming one (Fig. 2; see also Hardie, 1996, Fig. 5). The son’s data led Mackenzie and Agegian subset of this group are species that have fact that the Spencer-Hardie and Hardie (1989, p. 20) to conclude that “the oscilla- secreted unusually massive skeletons for models successfully predict the Phanero- tory trend seen in non-skeletal carbonate the higher taxa to which they belong; zoic history of two different families of components … is not clearly apparent stony bryozoans of the Paleozoic are an nonskeletal minerals precipitated from in the mineralogy of fossil organisms.” example. A second, overlapping subset seawater—carbonates and potash evap- Wilkinson’s data also dissuaded Van de of hypercalcifiers includes species whose orites—makes a strong case that both Poel and Schlager (1994) from claiming populations engage in rampant carbonate models are fundamentally valid. such a correspondence, although their sur- production. Reef builders and major sedi- vey of bioclasts in Mesozoic and Cenozoic ment producers fall within this category. STRATEGIES FOR UNCOVERING carbonate rocks indicated maxima for As a second strategy, we hypothesized TRENDS IN BIOMINERALIZATION aragonitic components in Triassic and that relatively unsophisticated carbonate late Cenozoic strata. secretors—ones that exert weak control From sparse data, Wilkinson (1979) Rather than conducting a general sur- over the chemical milieu in which they proposed a unidirectional Phanerozoic vey, we adopted a double strategy to inves- secrete their skeletons—are strongly influ- trend from calcite to aragonite for the enced by the Mg/Ca ratio and temperature of seawater. Significant here is the obser- vation that magnesium increases with temperature in the skeletons of modern marine organisms, as in nonskeletal marine carbonates, but partition coeffi- cients vary among taxa and the effect of temperature is inversely related to biologi- cal complexity (Chave, 1954). Employing these two strategies, we uncovered a strong correspondence between the mineralogy of biologically simple hypercalcifying taxa and that of nonskeletal carbonates from Ordovician time to the present (Fig. 2). We conclude that although these taxa, including reef builders, need not have secreted skeletons that were in thermodynamic equilibrium with seawater, their skeletal productivity has been strongly influenced by the ambi- ent Mg/Ca ratio. The taxa that yield this pattern share one deficiency: they are unable to remodel their skeletons through resorption during their ontogeny. It appears that the inability to remodel is linked to unsophisticated modes of biocalcification that also result in reliance on favorable seawater chemistry. Foraminifera, though otherwise simple organisms, are sophisti- cated skeletal secretors, which employ an “almost unparalleled” variety of basic modes of mineralization (Lowenstam and Weiner, 1989, p. 670) and also have the ability to remodel their tests; there is no apparent overall temporal relationship between their predominant mineralogy and the Mg/Ca ratio of seawater. Reef builders are probably heavily influenced by the ambient Mg/Ca ratio for two rea- sons. First, they must meet the basic demands of hypercalcification. Second, nearly all organisms able to flourish in the severe competitive battle for space within reef-building communities have succeeded through vegetative or colonial growth. Thus, these organisms have characteristi- cally been simple forms, such as algae, Figure 2. Correspondence between secular oscillations for the carbonate mineralogy of dominant sponges, and corals, which are unsophisti- hypercalcifying marine taxa, the mineralogy of marine evaporites and nonskeletal carbonates, and the Mg/Ca ratio and absolute concentration of calcium (Ca) in seawater as calculated by Hardie (1996). The cated carbonate secretors. As described below, application of our boundary separating the nonskeletal nucleation fields of low-magnesium calcite (< 4 mol% MgCO3), which we will term calcite, and high-Mg calcite (> 4 mol% MgCO3) and aragonite is shown as a hori- strategies to the geologic record provides zontal line at Mg/Ca = 2 (after Stanley and Hardie, 1998). explanations for many previously puzzling

4 GSA TODAY, February 1999 ern type (scleractinians) joined them as high taxonomic diversity during Early dominant reef builders (Stanley, 1988). Cretaceous time but had failed to form The only discrepancy between the massive chalk deposits. Following the set- mineralogy of dominant reef builders and back of calcareous nannoplankton by the that of nonskeletal carbonates is for Late terminal Cretaceous extinction, massive Jurassic and Early Cretaceous time, when chalk deposition resumed in early Pale- scleractinian corals persisted as major reef ocene time. Then, as the Mg/Ca ratio builders. The continued success of this of seawater rose toward the aragonitic aragonitic group probably resulted from domain, widespread deposition of massive two circumstances. First, the Mg/Ca ratio chalk ceased, and it failed to resume even remained near the calcite-aragonite during the exceptionally warm Eocene boundary during this interval. Second, interval, when epicontinental seas were the high absolute concentration of Ca2+ widespread. during this interval may have promoted The attribution of extensive chalk nonequilibrium precipitation of all forms deposition to changes in seawater chem- of calcium carbonate. In mid-Cretaceous istry gains support from the observation time, when the Mg/Ca ratio descended to that an increase in the concentration of its lowest Phanerozoic level according to dissolved Ca2+ enhances calcification by the calculations of Hardie (1996), corals calcareous nannoplankton in the labora- relinquished to rudists their role as domi- tory (Blackwelder et al., 1976). Additional nant reef builders (Scott, 1984). As bivalve support comes from two puzzling tempo- mollusks, rudists were probably not ral patterns for coccoliths (Houghton, strongly influenced by seawater chemistry. 1991). One of these is a polyphyletic Figure 3. Experimentally determined nucleation Thus, although shells of radiolitids, the decline in the mean size of coccoliths fields of low-Mg calcite (red), high-Mg calcite + most successful reef-building rudists of the during the Cenozoic Era. The result was aragonite (blue), and aragonite (green) in MgCl2- CaCl2-Na2CO3-H2O solutions at 28 ˚C, atmo- Late Cretaceous, contained more calcite thinner calcitic encrustation of cells. spheric pCO2 and 1 atm total pressure (1976 than aragonite (Kauffman and Johnson, The second pattern pertains to the genus unpublished data of Füchtbauer and Hardie). 1988), it is most reasonable to view the Discoaster. Coccoliths of this genus were Red symbol—calcite with MgCO3 content up rudists as beneficiaries of the decline solid, circular shields early in the Ceno- to 4 mol%; half-solid red square—calcite with of aragonitic reef-building corals that zoic, but as the era progressed, they be- MgCO3 content >4, <6 mol%. MgCO3 content of high-Mg calcite in the blue symbol field increases occurred when the Mg/Ca ratio dropped. came increasingly diminished in volume systematically with increase in the Mg/Ca ratio in Support for this interpretation comes from by marginal embayments. By the time the aqueous solution (see Füchtbauer and Hardie, the previously unexplained failure of Discoaster became extinct in the Pliocene, 1976, 1980). Black star—modern seawater (SW). corals to build large reefs for more than all of its members secreted spindly, star- 30 m.y. after the disappearance of the rud- shaped coccoliths that covered only a ists at the end of the Cretaceous Period. small fraction of the cell surface (Fig. 4). Scleractinian corals existed in considerable These trends for coccoliths can be viewed phenomena in the history of reef building diversity early in the Cenozoic Era, but as amounting to evolutionary osteoporosis, and sediment production and in the evo- produced only small, inconspicuous bio- caused by an increase in the Mg/Ca ratio lution of calcareous taxa. herms, even during the extremely warm of seawater that was accompanied by a de- Eocene interval. Not until early in the cline in the concentration of Ca2+ (Fig. 2). DOMINANT REEF BUILDERS Oligocene did corals begin to produce The Mg/Ca model also provides an Before Late Ordovician time, reefs massive reefs throughout the world (Frost, explanation for patterns of hypercalcifica- were built by taxonomically problematical 1977), despite the fact that warm seas had tion for green algae. Aragonitic codiaceans taxa of uncertain mineralogy. For this rea- contracted toward the equator (Zachos (especially Halimeda) produce vast quanti- son, we began our analysis of the mineral- et al., 1994). At this time, the Mg/Ca ratio ties of carbonate sediment today, and ogy of reef builders with the reef commu- of seawater was rising far into the arago- dasycladaceans were so productive during nity that flourished from Late Ordovician nitic regime (Fig. 2). Aragonite II that they have been regarded to Late Devonian time in the calcite sea We have provided elsewhere a more as the Halimeda of the Triassic (Elliott, designated Calcite I (Fig. 2). In accordance detailed picture of the correspondence 1984). On the other hand, the massive, with our hypothesis, this community was between the mineralogy of major reef calcitic receptaculitids were significant dominated by calcitic taxa: stromato- builders and nonskeletal marine carbon- sediment producers throughout Calcite I. poroid sponges and several groups of ates (Stanley and Hardie, 1998). Aspects of calcitic corals (Oliver and Coates, 1987). the pattern we have described were noted EVOLUTIONARY TRENDS The Late Devonian mass extinction by Van de Poel and Schlager (1994) and The Cenozoic evolutionary trend decimated the calcitic reef community. Hallock (1997). toward weakly calcified nannoplankton Late in the Mississippian Period, the species appears to reflect the influence Mg/Ca ratio of seawater shifted far into DOMINANT SEDIMENT of seawater chemistry (Fig. 4). Among the aragonitic regime (Aragonite II), and PRODUCERS cheilostome bryozoans, changes in the new reef-building communities of arago- The widespread deposition of massive Mg/Ca ratio appear to have influenced nite and high-Mg calcitic algae and chalk during Late Cretaceous time is the evolution of skeletal mineralogy. The sponges emerged (Fig. 2). Members of another phenomenon of hypercalcifica- cheilostomes originated as a calcitic group these communities formed the enormous tion that has long defied explanation but during the Cretaceous Period (Calcite II), Horseshoe Atoll of central Texas and the can be accounted for by a change in sea- although a few species of one subgroup Permian reef complex of west Texas. Arag- water chemistry: it coincided with the secreted a combination of calcite and arag- onitic members of the same and similar interval during which the Mg/Ca ratio was onite (Boardman and Cheetham, 1987). taxa emerged as the reef-building com- at its lowest level during the past 500 m.y. Fully aragonitic species did not arise until munity of the Middle Triassic, and in Late (Fig. 2). Calcareous nannoplankton— Triassic time aragonitic corals of the mod- potential chalk producers—had attained Hypercalcification continued on p. 6

GSA TODAY, February 1999 5 reefs. If, long after forming, reef carbonate Figure 4. becomes metamorphosed during orogene- Stratigraphic ranges sis, it will release CO to the atmosphere of typical species of 2 Discoaster, a genus (Berner, 1994). The flux of oxidized carbon of calcareous nanno- to reef carbonate reservoirs would have plankton whose calcitic been reduced at times, such as the early skeletal elements Cenozoic, when an unfavorable Mg/Ca underwent a striking ratio suppressed reef building. Carbonate net evolutionary trend during the sharp storage in reefs increased dramatically Cenozoic rise in the early in Oligocene time, following the Mg/Ca ratio of sea- shift from calcite to aragonite seas. At water. Species with about the same time, through reduced heavy, shield-shaped productivity during the dramatic rise in coccoliths gave the Mg/Ca ratio of seawater, nannoplank- way to species with delicate, star-shaped ton began contributing progressively less coccoliths. (Modified carbonate to the deep sea for possible from Houghton, future subduction and release of CO2. 1991.) Thus, during the past 30 m.y. or so, the increasing Mg/Ca ratio of seawater has influenced the relative proportions of total carbonate that have accumulated in the Hypercalcification continued from p. 5 tial to optimize their skeletal structures deep sea and in shallow-water reefs, where without inhibition by the Mg/Ca ratio of the mean residence time for oxidized the Eocene Epoch, when the Mg/Ca ratio seawater. Ammonoids, which secreted thin carbon is much longer. of seawater had risen markedly. Today shells within which the gas pressure was most cheilostome species secrete high-Mg about 1 atm, must have been served well ACKNOWLEDGMENTS calcite, but many tropical species secrete by the relatively great bending strength aragonite (Rucker and Carver, 1969); this of their nacreous aragonite. Ammonoids We thank Ronald E. Martin and distribution corresponds to the tempera- should therefore have benefited from their George D. Stanley for helpful reviews of ture pattern for nonskeletal precipitation ability to secrete aragonite readily even in our manuscript. of carbonates in laboratory experiments calcite seas. Thus, although being rela- (Morse et al., 1997). tively independent of the ambient Mg/Ca REFERENCES CITED Several workers have noted that the ratio leaves a taxon such as the Ammo- Baker, E. T., German, C. R., and Elderfield, H., 1995, mineralogy of calcareous sponges has fre- noidea unable to benefit from a favorable Hydrothermal plumes over spreading-center axes: quently coincided with that of nonskeletal ratio, all else being equal, this indepen- Global distributions and geophysical inferences, in Humphries, S., et al., eds., Seafloor hydrothermal carbonates during the Phanerozoic (Reit- dence confers long-term ecologic stability. systems: Physical, chemical, biological and geological ner, 1987; Gautret and Cuif, 1989; Wood, Conversely, although unsophisticated car- interactions: American Geophysical Union 1991). Our survey suggests that calcareous bonate secretors, such as algae, sponges, Monograph 91, p. 47–71. sponges have in fact been at the mercy of and corals, automatically benefit from the Berner, R. A., 1994, GEOCARB II: A revised model of seawater chemistry throughout their his- presence of a favorable Mg/Ca ratio, these atmospheric CO2 over Phanerozoic time: American Journal of Science, v. 294, p. 56–91. tory (Fig. 2). During the Cretaceous, for forms also suffer severe declines when Blackwelder, P. L., Weiss, R. E. and Wilbur, K. M., 1976, example, all of them appear to have been the ratio shifts to an unfavorable domain; Effects of calcium, strontium, and magnesium on the calcitic, but all present-day representatives they tend to follow a “boom-or-bust” coccolithophorid Cricosphaera (Hymenomonas) carterae. secrete aragonite, high-Mg calcite, or a pattern of productivity—and perhaps also 1. Calcification: Marine Biology, v. 34, p. 11–16. combination of these minerals (Hartman, taxonomic diversity—in the course of Boardman, R. S., and Cheetham, A. H., 1987, Phylum 1980). geologic time. Bryozoa, in Boardman, R. S. and Rowell, A. H., eds., Fossil invertebrates: Palo Alto, California, Blackwell, Martin (1995) has noted that some We think it likely that the Mg con- p. 497–549. suborders of foraminifera originated with centration in skeletons of taxa that secrete Burton, E. A. and Walter, L. M., 1991, The effects of skeletal mineralogies corresponding to high-Mg calcite has been positively corre- PCO2 and temperature on magnesium incorporation those of nonskeletal carbonates, although, lated with the Mg/Ca ratio of seawater in calcite in seawater and MgCl2-CaCl2 solutions: Geochimica et Cosmochimica Acta, v. 55, p. 777–785. as we have already noted, there does not back through Phanerozoic time, just as appear to be a strong temporal correlation today the Mg concentration in calcite Chave, K. E., 1954, Aspects of the biogeochemistry of magnesium 1. Calcareous marine organisms: Journal between the Mg/Ca ratio of seawater and skeletons increases with increasing ocean of Geology, v. 62, p. 266–283. the mineralogy of highly productive temperature (Chave, 1954). Experimental Elliott, G. F., 1984, Climatic tolerance in some foraminifera. growth of modern species under varying aragonitic green algae of the post-Palaeozoic: Palaeo- ambient Mg and Ca concentrations could geography, Palaeoclimatology, Palaeoecology, v. 48, p. 163–169. DISCUSSION shed light on this possibility by demon- strating lability in skeletal mineralogy for Frost, S. H., 1977, Miocene to Holocene evolution of The fact that we have been able to Caribbean Province reef-building corals: Proceedings, individual organisms. Study of the abun- connect many previously problematical Third International Coral Reef Symposium, Miami, dance of exsolved microdolomite and of p. 353–355. phenomena with a single causal explana- trace elements in fossils may also expand Füchtbauer, H., and Hardie, L. A., 1976, Experimentally tion gives credence to the Mg/Ca model. our knowledge of skeletal Mg concentra- determined homogeneous distribution coefficients for The results have additional biologic and precipitated magnesian calcites: Application to marine tions for extinct taxa. geologic implications, some of which sug- carbonate cements: Geological Society of America Changes in carbonate productivity Abstracts with Programs, v. 8, p. 877. gest promising avenues for future research. resulting from shifts in the Mg/Ca ratio For many taxa, degree of ecologic Füchtbauer, H., and Hardie, L. A., 1980, Comparison of of seawater must have affected the carbon experimental and natural magnesian calcites: Bochum, stability exhibited over tens or hundreds cycle significantly in the course of geo- Germany, International Association of Sedimentolo- of millions of years seems to reflect the gists, p. 167–169. logic time. Today, a large proportion of degree to which seawater chemistry has Gautret, P., and Cuif, J.-P., 1989, Les démosponges carbonate and bicarbonate ions entering influenced skeletal mineralogy. Sophisti- calcifiées des bioherms du Jurassique supérieur du the ocean are incorporated into organic cated carbonate secretors have the poten-

6 GSA TODAY, February 1999 CALL FOR NOMINATIONS REMINDERS Memorial Preprints DISTINGUISHED SERVICE AWARD The GSA Distinguished Service Award recognizes individuals The following memorial preprints are now avail- for exceptional service to the Society. GSA Members, Fellows, able, free of charge, by writing to GSA, P.O. Box 9140, Associates, or, in exceptional circumstances, GSA employees may Boulder, CO 80301. be nominated for consideration. Any GSA member or employee may make a nomination for the award. Awardees are selected by Arthur A. Baker Robert M. Kosanke the Executive Committee, and all selections are ratified by the J. David Love Aureal T. Cross, Jack A. Council. Deadline for nominations for 1999 is MARCH 1, 1999. Simon, Tom L. Phillips Frederick Betz, Jr. JOHN C. FRYE ENVIRONMENTAL GEOLOGY AWARD In cooperation with the Association of American State Geolo- Rhodes W. Fairbridge Robert Luscher gists (AASG), GSA makes an annual award for the best paper on McMaster environmental geology published either by GSA or by one of the Thomas E. Bolton John A. Peck state geological surveys. The award is a $1,000 cash prize from the Godfrey S. Nowlan, endowment income of the GSA Foundation’s John C. Frye Memo- Charles H. Smith John Elliott Nafe rial Fund. Jack E. Oliver The paper must be selected from GSA or state geological sur- Robert Sinclair Dietz vey publications; it must be selected from those published during Steve Koppes John Mason Parker III the preceding three full calendar years; and the nomination must Stephen G. Conrad include a paragraph stating the pertinence of the paper. John Van Nostrand Nominated papers must establish an environmental problem Dorr II John Evans Riddell or need, provide substantive information on the basic geology or Jacob E. Gair Richard C. Schmidt geologic process pertinent to the problem, relate the geology to the problem or need, suggest solutions or provide appropriate Charles Lum Drake Robert H. Shaver land-use recommendations based on the geology, present the Bruce B. Hanshaw Donald E. Hattin, information in a manner that is understandable and directly Carl B. Rexroad usable by geologists, and address the environmental need or Melvin (Mel) Friedman resolve the problem. It is preferred that the paper be directly John M. Logan, Thomas A. Simpson, Sr. applicable by informed laypersons (e.g., planners, engineers). David W. Stearns Philip E. LaMoreaux, Deadline for nominations for 1999 is MARCH 1, 1999. Everett Smith, James D. Hume Charles W. Copeland NATIONAL AWARDS Charles E. Stearns The deadline is April 30, 1999, for submitting nominations for these four awards: William T. Pecora Award, National Medal of Science, Vannevar Bush Award, Alan T. Waterman Award.

sud Tunisien (Oxfordien de la région de Tataouine): Morse, J. W., Wang, Q., and Tsio, M. Y., 1997, Spencer, R. J., and Hardie, L. A., 1990, Control of sea- Geobios, v. 22, p. 49–63. Influences of temperature and Mg:Ca ratio on CaCO3 water composition by mixing of river waters and mid- precipitates from seawater: Geology, v. 25, p. 85–87. ocean ridge hydrothermal brines, in Spencer, R. J., and Hallock, P., 1997, Reefs and reef limestones in earth his- Chou, I.-M., eds., Fluid-mineral interactions: A tribute tory, in Birkeland, P., ed., Life and death of coral reefs: Müller, G., Irion, G., and Förstner, U., 1972, Formation to H. P. Eugster: Geochemical Society Special Publica- New York, Chapman and Hall, p. 13–42. and diagenesis of inorganic Ca-Mg carbonates in the tion 19, p. 409–419. lacustrine environment: Naturwissenschaften, v. 59, Hardie, L. A., 1996, Secular variation in seawater chem- p. 158–164. Stanley, G. D., 1988, The history of Mesozoic reef com- istry: An explanation for the coupled secular variation munities: A three-step process: Palaios, v. 3, p. 170–183. in the mineralogies of marine limestones and potash Oliver, W. A., and Coates, A. G., 1987, Phylum evaporites over the past 600 m.y.: Geology, v. 24, Cnidaria, in Boardman, R. S., and Rowell, A. H., eds., Stanley, S. M., and Hardie, L. A., 1998, Secular oscilla- p. 279–283. Fossil invertebrates: Palo Alto, California, Blackwell, tions in the carbonate mineralogy of reef-building and p. 140–193. sediment-producing organisms driven by tectonically Hardie, L. A., and Eugster, H. P., 1970, The evolution of forced shifts in seawater chemistry: Palaeogeography, closed-basin brines: Mineralogical Society of America Plummer, L. N., Parkhurst, D. L., Fleming, G. W., and Palaeoclimatology, Palaeoecology v. 144, p. 3–19. Special Publication 3, p. 273–290. Dunkle, S. A., 1988, A computer program incorporating Pitzer’s equations for calculation of geochemical Van de Poel, H. M., and Schlager, W., 1994, Variations Hartman, W. D., 1980, Morphology of the skeleton: reactions: U.S. Geological Survey Water-Resources in Mesozoic-Cenozoic skeletal carbonate mineralogy: Sedimenta (University of Miami) VIII, p. 193–214. Investigations Report 88-4153, 310 p. Geologie en Mijnbouw, v. 73, p. 31-51. Houghton, S. D., 1991, Calcareous nannofossils, in Reitner, J., 1987, A new calcitic sphinctozoan sponge Wilkinson, B. H., 1979, Biomineralization, paleocean- Riding, R., ed., Calcareous algae and stromatolites: belonging to the Demospongiae from the Cassian For- ography, and the evolution of calcareous marine Berlin and Heidelberg, Springer-Verlag, p. 217–266. mation (Lower Carnian; Dolomites, northern Italy) organisms: Geology, v. 7, p. 524–527. Kauffman, E. G., and Johnson, C. C., 1988, The mor- and its phylogenetic relationship: Geobios, v. 20, Wilkinson, B. H., and Algeo, T. J., 1989, Sedimentary phological and ecological evolution of Middle and p. 571–589. carbonate record of calcium-magnesium cycling: Upper Cretaceous reef-building rudistids: Palaios, v. 3, Rucker, J. B., and Carver, R. E., 1969, A survey of the American Journal of Science, v. 289, p. 1158–1194. p. 194–216. carbonate mineralogy of cheilostome Bryozoa: Journal Wood, R. A., 1991, Problematic reef-building sponges, Lowenstam, H. A. and Weiner, S., 1989, On biomineral- of Paleontology, v. 43, p. 791–799. in Simonetta, A. M., and Morris, S. C., eds., The early ization: New York, Oxford University Press, 324 p. Sandberg, P. A., 1983, An oscillating trend in Phanero- evolution of Metazoa and the significance of problem- Mackenzie, F. T., and Agegian, C. R., 1989, Biomineral- zoic nonskeletal carbonate mineralogy: Nature, v. 305, atic taxa: Cambridge, UK, Cambridge University Press, ization and tentative links to plate tectonics, in Crick, p. 19–22. p. 113–124. R. E., ed., Origin, evolution, and modern aspects of Sandberg, P. A., 1985, Nonskeletal aragonite and pCO Zachos, J. C., Stott, L. C., and Lohmann, K. C., 1994, biomineralization in plants and animals: New York, 2 in the Phanerozoic and Proterozoic, in Sundquist, E. T. Evolution of early Cenozoic marine temperatures: Plenum Press, p. 11–27. and Broecker, W. S., eds., The carbon cycle and atmo- Paleoceanography, v. 9, p. 353–387. Mackenzie, F. T., and Morse, J. W., 1992, Sedimentary spheric CO : Natural variations Archean to present: 2 Manuscript received November 15, 1998; carbonates through Phanerozoic time: Geochimica et American Geophysical Union Monograph 32, accepted December 7, 1998 ■ Cosmochimica Acta, v. 56, p. 3281–3295. p. 585–594. Martin, R. E., 1995, Cyclical and secular variation in Scott, R. W., 1984, Evolution of Early Cretaceous reefs microfossil biomineralization: Clues to the biogeo- in the Gulf of Mexico: Paleontographica Americana, chemical evolution of Phanerozoic oceans: Global and v. 54, p. 406–412. Planetary Change, v. 11, p. 1–23.

GSA TODAY, February 1999 7 SAGE REMARKS Making Visualization Accessible to Students

Daniel C. Edelson, Matthew Brown, Douglas N. Gordin, Duane A. Griffin School of Education and Social Policy and Institute for the Learning Sciences, Northwestern University

Scientific Visualization tist or open the pages of a geoscience jour- scientists do is extremely low. Recognizing for Learning nal without finding a computer-rendered the potential value of scientific visualiza- Scientific visualization technologies visualization of scientific data. However, tion as a technology to support science have had an enormous impact on the geo- if you were to walk into a classroom, dorm learning, we have been engaged for several sciences. Visualization as a technology for room, or laboratory where students are years in the development of tools to make both investigation and communication working on their homework for a “geo” visualization and data analysis accessible has become almost ubiquitous. It is diffi- class, the odds of finding them construct- to learners. cult to walk into the office of a geoscien- ing or analyzing visualizations the way Visualization offers great promise for education (Gordin and Pea, 1995) for sev- eral reasons. The same advantages that sci- entific visualization offers to scientists also hold for students. Visualization exploits the power of the human visual system for finding patterns in imagery, allowing an individual to interpret data visually, with- out requiring sophisticated mathematical operations. Therefore, visualization can remove mathematical skills as a gatekeeper to working with scientific data. As a tech- nology for scientific investigation, visual- ization provides the opportunity to engage students in authentic inquiry as part of the learning process. Participation in meaningful inquiry is increasingly being recognized as a critical component of science education, as evidenced by the prominent role of inquiry in the national science education standards (National Research Council, 1996). Inquiry activities allow students to better understand the practice of science and interpret the results emerging from scientific research. “Literacy” with visualization has become an important skill for both practicing sci- entists and informed citizens. On the one hand, the use and manipulation of visual- ization is growing across a broad range of scientific disciplines, as well as mathemat- ics, information processing, and finance. On the other, images and animations pro- duced through the techniques of scientific visualization are becoming increasingly Figure 1. A WorldWatcher visualization window. common in both the print media and on television. It hasn’t been easy to bring visualiza- tion into the classroom, even if you have the appropriate technology infrastructure. If you are an earth or environmental sci- Figure 2. A World- ence teacher at the secondary school or Watcher diagrammatic college level and you want to give your interface to a library of students the experience of working with data illustrating Earth’s scientific visualization, you have histori- energy budget. Click- cally faced a frustrating choice. You can ing on any variable either teach your students how to use name in the diagram brings up a list of one of the powerful, general-purpose visu- dates to select. alization tools used by scientists, or you can have them view visualizations with an image viewer. Teaching students to use sci- entists’ tools is difficult, if not impossible, to do with many populations of students

8 GSA TODAY, February 1999 CALL FOR NOMINATIONS To reward and encourage teaching excellence in CALL FOR APPLICATIONS AND NOMINATIONS FOR beginning professors of earth science at the college level, the Geological Society of America announces: Geology Co-Editor

GSA is soliciting applications and nominations for the THE EIGHTH ANNUAL position of co-editor of Geology, to serve a three-year term, beginning in June 1999, as one of a two-editor team. Desirable characteristics for the successful candidate include: 1. Broad interest and experience in geology; Biggs Award international recognition 2. Iconoclastic; willing to take risks and try innovations For Excellence In Earth Science 3. Familiar with many earth scientists and their work Teaching For Beginning Professors 4. Sense of perspective and humor 5. Organized and productive ELIGIBILITY: All earth science instructors and faculty at 2- 6. Willing to work closely with GSA headquarters staff and 4-year colleges who have been teaching full time for 10 7. Able to make decisions years or less. (Part-time teaching is not counted in the 10 years.) 8. Sense of fairness 9. Familiar with new trends in geoscience AWARD AMOUNT: An award of $750 is made possible as a 10. Willing to consider nontraditional research in result of support from the Donald and Carolyn Biggs Fund, geosciences the GSA Geoscience Education Division, and GSA’s Education, Outreach, & Policy Programs. This award also GSA provides the editor with a small stipend as well as includes up to $500 in travel funds to attend the award expenses for secretarial assistance, mail, and telephone. presentation at the GSA annual meeting. If you wish to be considered, please submit a curriculum NOMINATION PROCEDURE: For nomination forms vitae and a brief letter describing why you should be chosen. contact Gwenevere Torres, Project Coordinator, Education, If you wish to nominate another, submit a letter of nomina- Outreach, & Policy Programs, Geological Society of America, tion and the individual’s written permission and c.v. Send P.O. Box 9140, Boulder, CO 80301, [email protected].. nominations and applications to Peggy S. Lehr, Director of DEADLINE: Nominations and support materials for Publications, Geological Society of America, P.O. Box 9140, the 1999 Biggs Earth Science Teaching Award must be Boulder, CO 80301, by April 14, 1999. received by April 30, 1999.

and consumes precious time that any WorldWatcher • Alternative representations. Differ- teacher would prefer to devote to learning WorldWatcher is a tool for the visual- ent representations of data can support science. On the other hand, image view- ization and analysis of gridded, geographic different forms of analysis. Therefore, ers, while they are easy to use, only allow data (Fig. 1). The design of WorldWatcher WorldWatcher provides multiple geo- students to view visualizations constructed has been focused on understanding the graphic projections for data, as well as by others, not to construct, customize, or supports required by learners to enable alternative representations such as his- manipulate them themselves. In other them to engage in meaningful investiga- tograms, line plots, and scatter plots. words, they do not allow students to work tions with geographic data. • Record keeping and documenta- with visualizations in the way that scien- To support meaningful inquiries, we tion. Conducting a successful investiga- tists do. Recognizing the unsatisfactory determined that a visualization environ- tion requires that students be able to nature of both of these alternatives for ment must support the following opera- maintain records of their work. World- most teachers, we set out to create a visu- tions: Watcher provides a notebook facility alization environment for geographic data • Customization of visualizations. that allows students to record their that is designed specifically for students. In order to interpret data effectively activities in the form of text, images Our goal was to create a software environ- through visual representations, learners of visualizations, and hypermedia links ment that provides the power of scientists’ must be able to customize those repre- to data. This same notebook facility is tools for the creation and customization sentations to highlight important pat- used to provide documentation for of visualizations and the analysis of data, terns in the data. In WorldWatcher, the data and operations available in while providing the support and structure users are able to modify the colors used WorldWatcher. necessary to make these operations acces- to represent values, the range of values These four criteria are not unique to a sible to students at the high school and displayed, the spatial resolution, and tool for students. They reflect the require- college level. Through a three-year, NSF- the magnification of an image. ments for supporting inquiry and apply funded educational research project, • Quantitative analysis of data. equally to scientists’ tools. However, the we developed a geographic visualization While a visual representation can dra- goal of supporting science learning adds and data analysis program, called World- matically improve a person’s ability to additional criteria. Because students lack Watcher, that achieves this balance. interpret data, it is not a substitute for the background knowledge that scientists WorldWatcher has been used successfully quantitative analytic techniques. World- bring to their use of visualization tools, in middle schools, high schools, and col- Watcher provides tools for simple statis- WorldWatcher is designed to provide leges, requiring no more than 45 minutes tical and arithmetic operations on data. the additional support students require of use to master its primary capabilities. It also allows users to identify specific regions within visualizations by specify- ing selection criteria. SAGE Remarks continued on p. 10

GSA TODAY, February 1999 9 SAGE Remarks continued from p. 9 assemble new WorldWatcher data libraries, supported investigations of global data build diagrammatic interfaces to these sets, and simple climate models, with role (Edelson and Gordin, 1998). This support libraries, and create documentation and playing and presentations in order to cre- takes several forms. First, visualization default display parameters for the data in ate a realistic setting for the investigation windows provide contextual information the libraries. These tools are designed to of hotly debated scientific issues. For exam- including continent overlays, latitude and enable scientists and curriculum develop- ple, in one set of activities, students con- longitude markings, and an active readout ers to write new WorldWatcher curriculum duct a traditional laboratory investigation displaying the current cursor location and units around any collection of raster (grid- of the effect of different colored materials underlying data values. Second, all data ded) data. on the absorption of light. They then files in WorldWatcher are tagged with apply the knowledge gained through this default visualization parameters that spec- Global Warming Curriculum lab to global climate processes by investi- ify initial settings for the color scheme, One of the primary curriculum gating WorldWatcher data sets showing range, units, and display resolution of the development efforts for WorldWatcher dominant ground cover, surface reflectiv- data. These default values enable learners has focused on the global warming con- ity, and absorbed solar energy for Earth. In to begin the interpretation of unfamiliar troversy as a motivating context for earth the culminating activity for this part of the data without needing to identify appropri- and environmental science education. curriculum, they must combine these find- ate visualization parameters first, as a sci- The Global Warming Project, designed in ings with other information about the entist would. Third, WorldWatcher pro- a partnership between teachers from the Earth-Sun relationship, and—using graphs vides diagrammatic interfaces to its data Chicago public schools and Northwestern and scientific visualizations to illustrate libraries (Fig. 2). These diagrammatic inter- University researchers, exemplifies our their points—explain to the UN secretary- faces play an important instructional role goal of integrating WorldWatcher into general the role that solar energy and by visually illustrating the relationships extended classroom investigations of real physical geography play in determining among variables. Finally, WorldWatcher scientific issues. Lasting for six to eight surface temperatures. In other parts of the provides operations not found in scien- weeks, the Global Warming Project places curriculum, students explore other relevant tists’ tools that were created specifically middle school and high school students in processes, such as the carbon cycle and the to support educational activities. For the role of scientific advisors to the secre- greenhouse effect, through similar combi- example, WorldWatcher contains a facility tary general of the United Nations, for nations of computer-based and conven- that allows users to create new data using help in finding out what the “global tional activities. a paint program interface. This facility is warming” issue really is about and what, used in learning activities in which learn- if anything, should be done about it. Acknowledgments ers “draw” maps to represent the state of To accomplish this goal, students The WorldWatcher software was their current understanding of a phe- must investigate how Earth’s climate written by Brian Clark. Roy Pea and Louis nomenon or to represent hypothetical works and how to detect any potential Gomez have also made critical contribu- situations. WorldWatcher also allows changes brought about by human activi- tions to the design of WorldWatcher and learners to print out cut-and-fold images ties. In a series of structured activities, its accompanying curricula. This research of two-dimensional visualizations that students investigate the meaning of tem- was supported by the National Science they assemble into three-dimensional perature change, the processes of energy Foundation program in Advanced Applica- polyhedral “globes.” transfer that control the climate on Earth, tions of Technology under grant RED- In addition to support for students, and the role of the atmosphere in main- 9453715. WorldWatcher is available at the design of WorldWatcher takes into taining Earth’s climate balance. Along the http://www.worldwatcher.nwu.edu/. account the needs of curriculum designers way, students present a series of back- and teachers. For example, the same note- ground briefings on their findings. At the REFERENCES CITED book facility that allows students to record conclusion of the unit, groups of students Edelson, D. C., and Gordin, D., 1998, Visualization for their work was designed to be used by must each advise a specific nation about learners: A framework for adapting scientists’ tools: teachers or curriculum developers to create the risks that might accompany predicted Computers and Geosciences, v. 24, p. 607–616. electronic “handouts” for students. These global climate change, and they offer con- Gordin, D. N., and Pea, R. D., 1995, Prospects for scien- handouts can contain instructions, back- crete, scientifically justifiable solutions for tific visualization as an educational technology: Journal of the Learning Sciences, v. 4, p. 249–279. ground information, and direct links to responding to or moderating these effects. National Research Council, 1996, National Science Edu- data. WorldWatcher also provides a suite The Global Warming Project combines cation Standards: Washington, D.C., National Academy of tools to allow nonprogrammers to hands-on labs, class discussions, computer- Press. ■

Alternates Receive visit 1998 Student Research Grants Each year when the Committee on Research Grants selects student grant recipients they also select an alternate group of recipients in the event that some of the grantees return US part or all of their funds because they have received funding elsewhere or have changed their research plans. As the returned funds become available, they are re-awarded by @http:// the Research Grants Administrator to the alternates named by the committee. In 1998 ten alternates received funding following the initial awarding of grants. They www are: Peter Sak, Pennsylvania State University; Ziya Cetiner, University of Idaho; Kelly Christin MacGregor, University of California, Santa Cruz; Molly A. Trecker, University of geosociety.org California, Santa Barbara; Sally L. Letsinger, Indiana University; Andrew J. Hooper, Uni- versity of North Carolina at Chapel Hill; Christopher M. Jengo, Bowling Green State Uni- shop the GSA Bookstore versity; Shafiul H. Chowdhury, Western Michigan University; Yiqiao Zou, New Mexico Institute of Mining and Technology; Garret L. Hart, University of Wisconsin—Madison. on the Web!

10 GSA TODAY, February 1999

WASHINGTON REPORT

Bruce F. Molnia, [email protected] Washington Report provides the GSA membership with a window on community. These reports present summaries of agency and interagency the activities of the federal agencies, Congress and the legislative pro- programs, track legislation, and present insights into Washington, D.C., cess, and international interactions that could impact the geoscience geopolitics as they pertain to the geosciences. An International Think Tank Takes a Glance at Education— OECD Indicators

The Organisation for Economic and education. These activities, which mir- • In France, obtaining a baccalaureate, the Co-operation and Development (OECD) ror the policy-making structures in the equivalent of a U.S. high school diploma, is a 29-member international consortium ministries of many governments, are per- ensures free enrollment in a university. The (Australia, Austria, Belgium, Canada, Czech formed in conjunction with national pol- United States remains one of the highest Republic, Denmark, Finland, France, Ger- icy-makers who ultimately use the analyses. spenders per student on education. many, Greece, Hungary, Iceland, Ireland, Annually, the OECD analyzes the • The United States stacks up well in Italy, Japan, Korea, Luxembourg, Mexico, state of education within its member teachers’ salaries—until the total spent Netherlands, New Zealand, Norway, countries and reports its findings to pro- on teachers’ salaries is calculated as a Poland, Portugal, Spain, Sweden, Switzer- vide international decision-makers with percentage of overall wealth. land, Turkey, United Kingdom, and United a scorecard showing where their countries • In the United States, the disparities States) that provides a forum for govern- rank and “reinforce accountability in between the highest and lowest perform- ments “to discuss, develop and perfect eco- national education systems.” The latest ing students are relatively large, increasing nomic and social policy.” The member review, Education at a Glance—OECD between the fourth and eighth grades. countries address common problems and Indicators 1998 Edition, a 432-page analy- High-achieving and low-achieving pupils attempt to coordinate domestic and inter- sis of education in 23 countries, was grow progressively further apart in perfor- national policies (i.e., establishing legally released in late November 1998. Some mance while they are at school. The gap binding codes for free flow of capital and of its more interesting findings include: between the highest and lowest perform- services). The forerunner of the OECD was • In the United States, Canada, Mexico, ing students is generally wider at age 13 the Organisation for European Economic and Spain, high school graduation rates than at age 9. In Korea, student perfor- Co-operation (OEEC), formed in the 1940s remain below 75%, although second- mance at age 9 is relatively uniform. to administer American and Canadian aid chance opportunities in Canada and the At age 13 it is more variable than in any under the Marshall Plan for the reconstruc- United States do allow dropouts the other OECD country. tion of Europe. Since it evolved out of the opportunity to complete high school at • Schools in some countries succeed in OEEC in 1961, the OECD has worked to older ages. (The latest statistics I obtained limiting this rise in dispersion. In Scotland build strong economies in its member from the U.S. Department of Education’s and in Greece, student scores do not countries, improve efficiency, hone market National Center For Education Statistics become significantly more dispersed over systems, expand free trade, and contribute showed that in the United States, for stu- the four grade years. to economic growth in industrialized and dents age 18 to 24, an estimated 83% of • Indicators show a continuation of a developing countries. whites, 77% of blacks, and 57% of Hispan- recent trend of increased educational A secretariat in Paris oversees ics received high school diplomas.) By spending as a proportion of national exchanges between OECD member govern- comparison, in Belgium, Finland, Japan, income, particularly at the university level. ments and provides for a flow of informa- New Zealand, Norway, and Poland, high This increase follows a several-decades tion and analyses between member school graduation rates are above 93%. trend of relatively stable spending. nations. The 1,850 employees of the OECD • Indicators show a clear private eco- • Universally, as education systems con- Secretariat collect data, monitor trends, nomic gain from participation at higher tinue to expand to meet growing youth analyze and forecast economic develop- levels of education. High unemployment populations, governments are having diffi- ments, investigate social changes, and in some European countries may be driv- culty meeting mounting bills for a greater study evolving patterns in trade, environ- ing people to seek higher education in number of students. ment, agriculture, technology, taxation, order to find jobs. • Most countries are spending more. Between 1990 and 1995 education spend- ing grew at a faster rate than national income in 14 out of 19 countries where information was available. In 10 countries, GSA ON THE WEB it grew more than 5% faster than income. Visit the GSA Web Site at http://www.geosociety.org. However, in Italy and Turkey, spending From our home page you can link to many information relative to Gross Domestic Product (GDP) resources. Here are some highlights: fell by 20% or more. GDP is the market value of all final goods and services pro- duced within a country during a given Check out GSA's Strategic Plan, recently posted on our Web site. period of time. Overall, educational spend- For specifics of this plan, click on GSA Strategic Plan under the heading ing accounts for at least 5% of the GDP. "What's Hot at GSA." Your comments are particularly welcome—please send • The increase in spending reflects rising them to [email protected]. educational aspirations. In countries where public funds are the primary source for financing education, serious pressure is being exerted on tight public budgets.

12 GSA TODAY, February 1999 • “Educational expectancy”—the average number of years spent at school during childhood and youth—is rapidly rising. In the first half of the 1990s, it rose from an average of less than 15 to 16+ years in the OECD countries. DIRECTOR, SCHOOL OF • The number of university students has GEOLOGY & GEOPHYSICS, increased in all countries between 1990 and and 1996. In half of the countries, the EBERLY FAMILY CHAIR IN increase is more than 30%. GEOLOGY AND GEOPHYSICS • Although education is primarily pub- licly funded, private spending is becoming at the increasingly important and accounts, UNIVERSITY OF OKLAHOMA on average, for 9% of educational funds. • Private spending accounts for more Applications and nominations are now being accepted for the position of Director, than half of final spending on university School of Geology & Geophysics at the University of Oklahoma, Norman. The education in three countries—Japan, Korea, and the United States. endowed Eberly Family Chair in Geology & Geophysics provides discretionary • On average, 34% of young people enroll resources to support the teaching and research activities of the Director. in university-level studies; 22% emerge with a degree. About two-thirds of stu- The School of Geology and Geophysics is internationally recognized for innova- dents enrolling in degree courses at tive, state-of-the-art research in petroleum-related fields, and attracts students who universities actually complete them. seek employment in the energy industry. The School has academic strengths in • University completion rates range from sedimentary systems, exploration and environmental geophysics, structural geol- above 80% in Hungary, Japan, and the ogy and rock mechanics, and organic and inorganic geochemistry. The School's United Kingdom to below 40% in Italy. faculty are committed to teaching and research in the basic geosciences, and are • Having a well-educated parent at least increasingly active in interdisciplinary programs beyond the School. doubles the chance of being well edu- cated. This emerges from a new indicator of “inter-generational educational mobil- The School is part of the College of Geosciences, whose other academic programs ity,” which compares number of adults are the School of Meteorology and the Department of Geography. The School is who are university graduates to the high- housed in the Sarkeys Energy Center and, along with other units in the Colleges of est educational level of their parents. Engineering, Arts & Sciences, and Business, is a key unit in that Center's multidis- • Typically, people whose parents do not ciplinary research and technical outreach activities. The School has close ties to have a high school education have a lower the Oklahoma Geological Survey and the Oklahoma Museum of Natural History. than one-in-five chance of becoming uni- versity graduates. Those whose parents are The School seeks a Director who will strengthen and enhance its leadership posi- university graduates have a two- to three- tion in petroleum geosciences, anticipate and react positively to the on-going rapid in-five chance of also becoming university graduates. changes in the geosciences, work with all stakeholders to forge a vision for the • Differences in level of educational com- School's future and bring it to reality, and work effectively to augment the School's pletion correlate with future earnings and funding base from private, industry, and government sources. Specific qualifica- career success in adulthood. By mid-career, tions for the Director include: career experience well beyond the doctorate in the level of education that adds most academia, industry, or government sufficient for tenure at the Full Professor level; to individuals’ earnings is university. an internationally recognized research program; demonstrated leadership skills; an On average, university graduates earn understanding and appreciation of all the research disciplines in the School; and 20%–100% more than high school demonstrated ability to communicate effectively with faculty, students, administra- graduates. tors, alumni, and industry representatives. The area of research expertise is open. • Adults who are university graduates also receive, on average, twice as much train- ing as high school graduates, who in turn Review of applications will begin February 15, 1999. Applications will be consid- receive twice as much as those with less ered until the position is filled. Applications and nominations should be sent to than a high school education. Thus, edu- Dr. John T. Snow, Dean, College of Geosciences, The University of Oklahoma, cation combines with other influences to 100 E. Boyd, Rm. 710, Norman, OK 73019-1008; telephone 405-325-3101/FAX make adult learning least common among 405-325-3148/e-mail [email protected]. Additional information may be obtained by those who need it most. viewing the College of Geosciences web site at http://geosciences.ou.edu. • Across OECD countries, men who are university graduates have an average of six The University of Oklahoma is an more years of employment than men who Affirmative Action, Equal Opportunity have not completed upper secondary edu- Employer. cation; for women the gap is 11 years. This 1998 report, Education at a Glance—OECD Indicators 1998 Edition, is available from the OECD Media Relations Division, OECD Washington Center, 2001 L Street, NW, Suite 650, Washington, DC 20036-4922, (202) 785-6323, toll-free number for orders 1-800-456-6323. ■

GSA TODAY, February 1999 13 GSAF UPDATE Digging Up the Past Robert L. Fuchs, Foundation Trustee Most Memorable geologic experience: Is There a Trust in Your Future? “What could be more memorable than meeting A recent article in one of the national ment of a trust. While probate records and a geologist who was business magazines began with the question real estate deeds are open to the public, later to become your “Have you set up a trust?” and went on to trusts cast a cloak of secrecy over an estate. wife and geological state, “If you haven’t, get cracking. No mid- The world does not need to know what partner?” dle-class family should be without one.” you have when you are alive, and to —Bruce F. Curtis Trusts have always been the financial whom your assets are left. tools of the rich, but inflation and Finally, a trust can be used to segregate changes in tax laws have lowered the your estate from certain heirs. This may be income and/or asset level at which trusts impossible to do in some states, where, for start to make sense for many people. example, you cannot totally disinherit a ciary. The trustee, who could be you, the You may be one of these. There are several spouse or children. Relatives who have Foundation, or a third party, sells the reasons why this has happened. been cut off have a much more difficult assets and places the proceeds in income- First, trusts are a very effective way time attacking your trust than your will. producing securities (which can be tax-free to minimize taxes. As inflation has caused There are a number of trust types municipal bonds). Recent lowering of the individual incomes and estates to increase, to suit particular needs in particular loca- capital gains tax rate has made growth the estate tax exemption of $650,000 in tions, such as the qualified terminable stocks an advantageous holding for 1999 has not kept pace with this increase. interest trust (QTIP), the generation- CRUTs. The income stream from the trust Many now find themselves above this skipping trust, the kiddie trust for college is paid to you (or your spouse) for life, and exemption level. Estate and income taxes tuition, and the grantor retained income the principal reverts to the Foundation can be reduced by shifting assets to a char- trust (GRIT). This is the domain of estate after death. There is no capital gains tax to itable remainder trust or a life insurance attorneys. The revocable living trust may pay at the time of the asset sale; your trust trust, for example. make a lot of sense for you if you live in receives the full value of the proceeds. Trusts can be used to avoid probate. one of the “heavy probate” states or have In addition to deferring this tax, there is In about a third of the states, probate is residences or property in more than one a year-of-gift tax deduction, adjusted for a costly, time-consuming, uncomfortable state. There is some work involved in set- life expectancies and the future income process. A revocable living trust can trans- ting one up, such as ensuring that all your stream. These tax advantages together fer assets to heirs outside of a will, and this assets are in fact transferred to the trust. can add up to a very powerful economic is usually done within a short time after However, your heirs may very well some incentive to create a CRAT or a CRUT. death. Fees for lawyers and court adminis- day appreciate your time and effort. A panoply of literature and software tration are greatly reduced in the process, The charitable remainder trust comes is available if you want to learn more or even eliminated. Not only is such a in two versions, the annuity trust (CRAT) about trusts. Call the Foundation at (303) trust important in states such as Califor- or unitrust (CRUT). Either can provide sig- 447-2020, extension 154, and we can give nia, New York, and Florida, ownership of nificant tax advantages during your life- you a few titles. In fact, we can send you property in other states can cause your time. The process of forming one of these an introductory booklet, “Trusts in Finan- will to be probated in those states even trusts is not particularly difficult. First you cial Planning,” which can help you decide though probate is not a significant prob- create and transfer assets to a trust that if there really is a trust in your future. You lem in your state of residence. names a charity or charities such as the may use the accompanying coupon to Privacy is an attribute of the establish- GSA Foundation as the remainder benefi- order this booklet. ■

Donors to the Foundation, November 1998

Claude C. Albritton Building Expansion Shirley Dreiss George R. Thompson* Edward A. Sudicky* Memorial Gordon P. Eaton*◆ Memorial Chunmiao Zheng History of Geology Vance T. Holliday Mary Jo Baedecker Cordilleran Section Award Institute for John C. Kraft Philip C. Bennett*◆ Endowment Norman B. Cranford◆ Environmental Robert Gordon Schmidt Maryellen Cameron*◆ Ian S. E. Carmichael◆ Gretchen Luepke Education Alan R. Dutton Biggs Excellence Paul E. Hammond◆ Gail M. Ashley Robert H. Fakundiny Hydrogeology in Earth Science Aaron Bobar Allan V. Cox Student David B. Rogers Division Award Education James E. Evans Scholarship Award Mary P. Anderson James F. Brooks Dwornik Planetary Ann I. Guhman George R. Thompson* Mary Jo Baedecker Parvinder S. Sethi◆ Geoscience Award Gretchen Luepke Jean M. Bahr Kurt M. Wilkie Doris M. Curtis John B. Adams Charles C. Rich John Van Brahana* Memorial Ronald Greeley* Ruth A. M. Schmidt Birdsall Award Anne E. Carey Siegfried Muessig* George E. McGill Jung Ok Shin George T. Cardwell James S. Dinger Ruth A. M. Schmidt* James R. Zimbelman Samuel E. Swanson*◆ Larry A. Jackson Charles W. Fetter* F. Michael Wahl*◆ Stavros S. Papadopulos Charles Lum Drake GEOSTAR Mark S. McBride International Award Charles F. Bisbee Stavros S. Papadopulos International Robert H. Fakundiny Gretchen Luepke Robert W. Ritzi Division Award *Century Plus Roster Peter S. Meyer◆ Walter C. Pusey III Frank W. Schwartz* Holly J. Stein◆ (gifts of $150 or more). James K. Roche◆ John M. Sharp, Jr. ◆Second Century Fund.

14 GSA TODAY, February 1999 John C. Frye Research Grants Environmental Charles A. Baskerville GSA Foundation Award Frederick B. Bodholt 3300 Penrose Place Michael R. Fisher Gary McG. Boone P.O. Box 9140 John P. Kempton William D. Carlson Boulder, CO 80301 Joan R. Clark John T. Dillon Alaska (303) 447-2020 • [email protected] Ronald B. Cole Scholarship Award Charles W. Collinson Christopher C. Puchner Brian J. Cooper Enclosed is my contribution in the amount of $______for the Sarah M. Roeske Russell C. Evarts* ______Fund. Ruth A. M. Schmidt* John A. Fagerstrom Please add my name to the Century Plus Roster (gifts of $150 or more). J. Hoover Mackin Martin B. Farley Award Michael R. Fisher I would like to learn more about trusts. Please send me a copy of the Daniel S. Barker Michael O. Garcia booklet entitled “Trusts in Financial Planning.” Robert E. Boyer* Swapan S. Ghosh◆ PLEASE PRINT William B. Bull Allen F. Glazner◆ P. Thompson Davis Fraser E. Goff Name ______Edwin H. East William K. Hart Robert H. Fakundiny David F. Hess Address ______William B. Hall William R. Holman Harvey M. Kelsey III Elizabeth Jacobson City/State/ZIP ______James C. Knox Myra Keep Phone ______Mary E. Savina◆ Wayne Kemp Robert Metz Carol G. and John T. William G. Minarik McGill Fund Tina M. Niemi Joan R. Clark Mark T. Duigon Ocean Energy, Inc.* Larry A. Jackson Stephen F. Personius Kelly M. Hazen◆ Roy E. Ervin William A. Oliver, Jr.* Memorial Fund Walter C. Pitman III Gregory J. Leonard EXXON Exploration Margaret M. O’Neill Lillian D. Berg Donald B. Potter◆ Samuel T. Martner Company* William C. Overstreet◆ in memory of Matt J. Pranter James R. Underwood, Jr.◆ Paul Geoffrey Feiss*◆ David H. Palmer◆ Joseph W. Berg, Jr.* Walter C. Pusey III Nanci E. Witbeck* Warren I. Finch Jeffry A. Parsons Avery and Colette John R. Reid, Jr. William S. Fyfe◆ Charles B. Peeples III Unrestricted Drake, Jr. in memory of Harold H. Stowell Joseph S. Gates William J. Perry, Jr. Francis D. Anderson Bruce B. Hanshaw* Desiree E. Stuart- Julian R. Goldsmith◆ Harriet E. Powell Thomas H. Anderson Gordon W. Prescott◆ Alexander William C. Goth D. P. Price Frank G. Andrews Bennie W. Troxel Lois T. W. Grady William C. Prinz Minority Fund Walter B. Ayers, Jr.◆ Robert J. Twiss Reinhard O. Greiling Walter C. Pusey III Michele L. Aldrich*◆ W. Robert A. Baragar Gregory S. Vandeberg Dennis H. Grindle William D. Romey◆ Charles A. Baskerville Manuel A. Barrantes Albert E. Wood* William R. Hackett Gerald M. Ross Ruth A. M. Schmidt William A. Bassett John K. Hall Sandra L. Rutherford SAGE Thomas Beard North-Central William B. Hall Takayuki Sakamoto Alicia K. Armstrong◆ Edward Scudder Belt◆ Section Endowment Paul E. Hammond◆ William M. Schill◆ Thomas M. Berg Daniel Bernoulli North-Central Section*◆ Joseph H. Hartshorn*◆ David M. Scotford Jeremy M. Boak◆ Charles F. Bisbee Richard L. Hay◆ Kenneth D. Seborowski Northeastern Section John R. Carpenter D. L. Blackstone◆ Alan S. Horowitz◆ Charles E. Seedorff* Endowment Tom Ann Casey John D. Bloch Peter J. Hudleston*◆ Seymour L. Sharps Joseph E. Nadeau◆ Robert A. Christman Arthur L. Bloom Cornelius S. Hurlbut, Jr.◆ Gordon G. Start William D. Romey◆ James A. Drahovzal Arthur A. Bookstrom Arthur Mekeel Hussey II Rowland W. Tabor Eric K. Ericson T. Leo Broin Penrose Conferences Larry A. Jackson Mya Mya Than◆ John L. Fauth William P. Brosge*◆ Sigmund Snelson Allen H. Johnson Theodoros Toskos Gretchen Luepke Bruce A. Brown Lisle T. Jory Bennie W. Troxel Desmond and Judy E. Allen Merewether Ian S. E. Carmichael*◆ E. A. Keller Peter R. Vail Pretorius Fund Roger B. Morrison Eric S. Cheney John P. Kempton◆ Bradley A. Wake Anonymous* Daniel P. Murray Edward H. Chown Kathryn C. Kilroy◆ John H. Wall Michael J. Passow◆ Kenneth W. Ciriacks*◆ Publications Konrad B. Krauskopf◆ A. L. Washburn◆ Pamela Polite-Fisco Sandra H. B. Clark Anonymous* Ronald B. Krauth Fred Webb, Jr. Charles C. Rich in memory of Albert G. Holba Gary F. Land Malcolm P. Weiss◆ Ruth A. M. Schmidt Bruce B. Hanshaw◆ Daniel J. Miller* Robert T. Littleton Raelyn E. Welch◆ Patricia O. Seaward Ronald J. Clendening◆ Donald D. Miller Helen Tappan Loeblich* John O. Wheeler Sigmund Snelson Susan Howes Conrad Martin G. Miller* Mark J. Logsdon* Robert T. White Brian J. Cooper Gerard M. Stampfli Southeastern Section Robert J. Malcuit William M. Whiting Doak C. Cox Endowment Ennio Marsella Donald R. Wiesnet Rip Rapp Richard Crook, Jr. Paul Geoffrey Feiss◆ Thane H. McCulloh Isaac J. Winograd Archaeological Graham R. Curtis John P. Kempton◆ Edgar J. McCullough, Jr.◆ James C. Wise Geology Award Jelle Zeilinga De Boer Roger B. Morrison Leonard Alton Wood Richard K. Dunn Shoemaker Edward C. de la Pena Sharon Mosher Margaret S. Woyski Memorial Fund for Robert W. Decker Bruce L. “Biff” Reed Joseph E. Nadeau◆ Frederick P. Zoerner Crater Studies Rodger E. Denison*◆ Scholarship James T. Neal Milford J. Benham◆ Bruce R. Doe Women in Science John H. Fournelle Occidental Oil & Gas Mary G. Chapman Julie M. Donnelly-Nolan Ruth A. M. Schmidt Corporation*

GSA TODAY, February 1999 15 16 GSA TODAY, February 1999 Final Announcement REGISTRATION Preregistration deadline: ROCKY MOUNTAIN SECTION, GSA March 5, 1999 51st Annual Meeting Preregistration is recommended for field trips and special activities because of The Last Best Rocky Mountain participation limits and required guaran- GSA Meeting of the Millennium tees. Use the Preregistration Form pro- vided in this announcement. Save time and money—preregister today! Pocatello, Idaho Full payment must accompany regis- April 8–10, 1999 tration. Unpaid purchase orders are not http://wapi.isu.edu/rm-gsa99 accepted as valid registration. Charge ★ cards are accepted as indicated on the pre- registration form. Please recheck the card number given, as errors will delay your daho State University will host the 1999 Geological Society registration. The confirmation card will of America Rocky Mountain Section meeting in Pocatello, Idaho. The meeting will be be your receipt. No other receipt will be held at Cavanaugh’s Pocatello Hotel and Convention Center off Interstate Highways I given. 86 and 15, approximately 150 miles north of Salt Lake City, 50 miles southwest of Idaho Register one professional or student Falls, and 120 miles east of Twin Falls, Idaho. Flanked by foothills and mountains of the per form. Copy the form for your records. Bannock and Portneuf ranges, Pocatello is located in the valley of the Portneuf River near Badges must be worn for access to all the margin of the Basin and Range and Snake River Plain geologic provinces. activities, 7 p.m. Wednesday through noon Saturday. Guest registration is SETTING AND ACCESS 3. Pocatello Super 8 Motel required for those attending meeting 1330 Bench Road, Pocatello, ID 83201 activities, including technical sessions. Pocatello is easy to access by air via Phone (208) 234-0888 Guest registrants must be accompanied by 12 flights each day from Boise on Horizon Reservations (800) 800-8000 a registered attendee. A guest is defined as Airlines, and from Salt Lake City on Sky- a nongeologist spouse or friend of a pro- west Airlines (Delta Connection). April 4. Holiday Inn fessional or student registrant. weather in eastern Idaho is always beauti- 1399 Bench Road, Pocatello, ID 83201 Students and K–12 professionals ful; days are typically 40–60 °F; nights are Phone (208) 237-1400 must show a current ID on site in order cool, with possible frost, or light snow. We Reservations (800) 200-8944 to obtain these rates. Students or K–12 look forward to an enjoyable and produc- 5. Ameritel Inn educators not having a current ID when tive meeting of “Poky ‘99—Spuds ‘R’ Us,” 1500 Bench Road, Pocatello, ID 83201 registering on site will be required to pay The Last Best Rocky Mountain GSA Meet- Phone (208) 234-7500 the professional fee. ing of the Millennium. See you in Reservations (800) 600-6001 On-site registration will be available Pocatello! at Cavanaugh’s from 4 to 7 p.m. Wednes- 6. Best Western Cotton Tree Inn day, 7:30 a.m. to 4 p.m. Thursday and Fri- ACCOMMODATIONS 1415 Bench Road, Pocatello, ID 83201 day, and 7:30 to 11 a.m. Saturday. Phone (208) 237-7650 A block of rooms has been reserved at Members pay less! You can join now or Reservations (800) 622-6886 Cavanaugh’s Pocatello Hotel and Conven- at the meeting. Come visit the GSA Mem- tion Center for April 7 through 10, 1999. A special rate of $60 per room is guaran- Rocky Mountain continued on p. 18 teed for GSA reservations made before POCATELLO AREA March 29, 1999. All rooms feature coffee, irons, hair dryers, and dataports. Cavanaugh’s is a full-service hotel with a restaurant, lounge, swimming pool, whirlpool, airport shuttle, and free park- ing. It is inexpensive and provides a con- venient location for all activities related to the GSA meeting. Additional space is available in nearby hotels, all within a few minutes’ walking distance. Attendees must settle with hotels on an individual basis (add 8% tax). 1. Cavanaugh’s Pocatello Hotel (Meeting Headquarters) 1555 Pocatello Creek Road Pocatello, ID 83201 Phone (208) 233-2200 Reservations (800) 325-4000 FAX (208) 234-4524 [email protected] 2. Comfort Inn 1333 Bench Road, Pocatello, ID 83201 Restaurants, etc.: A = Applebees; F = Frontier Phone (208) 237-8155 Pies; Sp = Sandpiper; Su = Subway; P = Perkins; Reservations (208) 237-8155 K = Circle K; J = Jack in the Box

GSA TODAY, February 1999 17 Rocky Mountain continued from p. 17 REGISTRATION FEES Bozeman, (406) 994-6913, Lageson@ montana.edu; Jim Sears, University of bership Services area for new member appli- Full One day Montana, Missoula. The unifying theory cations, reinstatements, dues payment, Professional— of the Yellowstone–Snake River Plain address changes, questions, or concerns. Member $60 $40 hotspot and associated topographic bulge Contact GSA for further information. Nonmember $60 $40 has spawned many types of studies. This symposium will cover the past 15 m.y. Cancellations, Changes, Student— of tectonics, volcanism, and drainage and Refunds Member $30 $15 development. All requests for registration additions, Nonmember $30 $15 Tectonic and Magmatic Evolution changes, and cancellations must be made K–12 Professional $30 $15 of the Snake River Plain. Bill Bonnich- in writing and received by March 12, 1999. Guest or Spouse $10 sen, Idaho Geological Survey, University GSA will refund or credit preregistration of Idaho, Moscow, ID 83844-3014, (208) fees for cancellations received in writing high integrity, and warm friendship for 885-8928, [email protected]; Craig White, by that date. No refunds or credits will be more than four decades. This banquet will Boise State University; Mike McCurry, made on cancellation notices received feature remarks by Lehi, and will extend Idaho State University. This oral and after March 12. Refunds will be processed to him thanks and congratulations from poster symposium, organized in conjunc- after the meeting. There will be no refunds the Rocky Mountain Section for his dedi- tion with an upcoming Idaho Geological for on-site registration and ticket sales. cation and leadership in studies of the Survey memoir, will focus on magmatism Accessibility for Registrants regional geology of Utah. and tectonics of the Snake River Plain, with Special Needs GSA Rocky Mountain Section which crosses the edge of cratonic North GSA is committed to making every Management Board Breakfast. Friday, America, and reflects much-debated man- event at the 1999 Rocky Mountain Section April 9, 1999, 6:30–8 a.m., Cavanaugh’s. tle influence. meeting accessible to all people. Special Idaho Association of Profes- Lehi Hintze Symposium on the requirements, such as an interpreter or sional Geoscientists (IAPG) Annual Geology of Utah. Bart Kowallis, Dept. wheelchair, will be provided upon request. Luncheon Meeting. Cavanaugh’s, of Geology, Brigham Young University, Please let us know your needs by Friday, April 9, noon. Price: $12. IAPG 258 ESC, Provo, UT 84602 (801) 378-8143, March 10, 1999. is the only comprehensive geoscience [email protected]. This symposium is organization in Idaho. A speaker will be dedicated to one of the fathers of Utah WELCOMING PARTY arranged. There will also be an update geology. Talks will cover all aspects of from the Idaho State Board for Registra- Utah geology, with an eye toward com- An informal ice-breaker reception tion of Professional Geologists. pleteness and updating progress on many will be held Wednesday, April 7, from Fun Run or Walk (5 km run, long-standing controversies, many of 7 to 9 p.m. next to the indoor pool at 2 km walk). Friday, April 9, 5:30 p.m., which relate to the long career of Lehi Cavanaugh’s. Don’t miss this opportunity hosted by the Idaho State University Geol- Hintze. to visit old friends and make new ones. ogy Club. First prize is a discovery flight Active Tectonics in the Basin and This will be a good opportunity to learn around Pocatello for the top finishers in Range. Bob Smith, 702 Browning Bldg., more about special events, spouse activi- male and female categories. Entry is FREE Dept. of Geology and Geophysics, Univer- ties, and the sites around Pocatello. Light to registered meeting participants. For sity of Utah, 135 So. 1460 East, Salt Lake food and beverages will be served. Atten- more information, contact Jordan City, UT 84112-0111, (801) 581-7129, dees must register before the party and will Vaughn, Geology Club, Dept. of Geology, [email protected]. This symposium receive a complimentary beverage coupon. Idaho State University, Pocatello, ID will concentrate on active tectonism and 83209, (208) 236-3235. neotectonics of the Basin and Range GUIDEBOOK Spuds ‘R’ Us Millennium Bash. province, including recent advances in A peer-reviewed monograph Friday, April 9, 7:30 p.m.–midnight, hosted observations, models, and geologic mani- Guidebook to the Geology of Eastern Idaho by the Idaho State University Department festation of active intraplate extension. (Scott Hughes and Glenn Thackray, of Geology, at the Booth Barn located near Topics include mechanisms of extension, editors) will be published by the Idaho the meeting. A shuttle van to and from especially how the Basin and Range is Museum of Natural History in conjunc- Cavanaugh’s will be provided. All atten- deforming today and how it fits into a tion with the meeting. Articles will dees and their spouses or friends are wel- framework of western U.S. deformation, include scientific discussion and road logs come. Really live music is planned. Cost: $5. seismicity, paleoseismicity, basin origin, to accompany the field trips, plus compre- geodetics, magmatism, epeirogeny, etc. hensive field guides and articles that TECHNICAL SESSIONS The symposium, while regional in focus, extend beyond the trips offered at the Symposia is global in significance because of the meeting. Cost for the guidebook is $25 We have an exciting program of sym- emphasis on continental intraplate purchased at the meeting, and $30 pur- posia dealing with geoscience in the inter- extension. chased after the meeting. All professional mountain West. Address general questions Proterozoic Rocks of Northern registrants for the meeting will receive a to Technical Program Chair Paul Link, Idaho and Vicinity. Reed S. Lewis, $10-off coupon for on-site purchase of the Dept. of Geology, Idaho State University, Idaho Geological Survey, Moscow, ID guidebook. Pocatello, ID 83209-8072, (208) 236-3846, 83842, (208) 885-7991, [email protected]; [email protected]. Mark McFadden, University of Idaho. Pro- SPECIAL EVENTS Past and Present Tectonics of the terozoic rocks underlie much of northern Circum-Yellowstone Bow Wave: Idaho and the surrounding area and are Rocky Mountain Section Southwest Montana, Northwest key to understanding the complex struc- Banquet in Honor of Lehi Hintze. Wyoming, and Southeast Idaho. tural history of the region. Symposium Cavanaugh’s, Thursday, April 8, 7 p.m. Rob Thomas, Dept. of Environmental topics include stratigraphy, structure, Price: $20 (choice of beef roulades, Sciences, Western Montana College of the geochronology, and mineral deposits chicken cordon bleu or vegetarian pasta University of Montana, Dillon, MT 59725- within the Proterozoic, with an emphasis primavera). Lehi Hintze has been a model 3598, (406) 683-7615, [email protected]; on the Belt Supergroup and the Yellow- of careful work, considerate mentoring, Dave Lageson, Montana State University, jacket Formation.

18 GSA TODAY, February 1999 Hydrologic, Geologic, and Biological tions, as well as environmental problems able to and from Cavanaugh’s. Cost: $50. Constraints on Waste Remediation solved or created by these minerals. Instructors: Keith Weber, (208) 236-2757, Technologies at the Idaho National Innovative Science Teaching in [email protected], and Michelle Byrd. Engineering and Environmental Idaho. Terry Kuroda, Meridian High Minimum: 10. Laboratory. Roy Mink, Idaho Water School, 1900 West Pine, Meridian, ID Introduction to ArcView GIS 3.1— Resources Research Institute, University 83642, (208) 888-4905. Some of the Half Day. This introductory workshop on of Idaho, Moscow, ID 83844-3011, (208) innovative members of the Idaho Science Saturday, April 10, 1 to 4 p.m., will cover 885-6431, [email protected]; Dale Ralston, Teachers Association will present posters, the first half of the Wednesday workshop. University of Idaho; Paul Link and John talks, and workshops that will be of inter- Educators and meeting guests are encour- Welhan, Idaho State University. This sym- est to K–12 educators at the elementary, aged to sign up for this session. The work- posium will focus on methods of charac- middle school, and high school levels. shop will be held in the newly constructed terizing and modeling the geology, con- Saturday morning, April 10. GIS Lab in the basement of Graveley Hall taminant hydrology and microbial Academic Service Learning in the on the Idaho State University Campus. ecology of the eastern Snake River Plain. Geoscience Curriculum. Sheila Roberts, A shuttle van will be available to and Presentations will include geology, geo- Dept. of Environmental Sciences, Western from Cavanaugh’s. Cost: $25. Instructor: physics, geochemistry, hydrogeology, and Montana College of the University of Michelle Byrd, [email protected]. microbiology of the regional aquifer sys- Montana, Dillon, MT 59725, (406) Minimum: 10. tem and its geologic environment and 683-7017, [email protected]; Dave their application to hazardous and Mogk, Montana State University, FIELD TRIPS radioactive waste remediation. (406) 994-6916, [email protected]. All field trips will depart from and Source-Water Protection in the Academic service-learning promotes return to the main parking lot of Rocky Mountain Region: Unique integration of research and service in Cavanaugh’s Hotel and Convention Cases and Lessons Learned. Willis undergraduate education. A well-designed Center. For general questions regarding Weight, Dept. of Geological Engineering, project supports the curriculum, motivates field trips, contact Glenn Thackray, Field Montana School of Mines of the Univer- students, and provides a professional ser- Trip Chair, ISU Geology, (208) 236-3560; sity of Montana, Butte, MT 59701, (406) vice. Service learning is also an underuti- [email protected]. For detailed information 496-4329, [email protected]. Geo- lized opportunity for outside funding. concerning a specific trip, please contact logically speaking, source-water topics in This half-day symposium-workshop will the trip leader. All field trip fees include the Rocky Mountain region are especially include talks to introduce the topic and transportation, lunch, and field trip guide. intriguing. Limited supply and heteroge- provide successful case studies, funding neous source terranes make for critical ideas, and a work session on project Premeeting Trips water-quality issues. design. 1. Past and Present Tectonics of Paleozoic Stratigraphy, Structure, the Greater Yellowstone Tectonic and Tectonics of Northeast Nevada. PROJECTION EQUIPMENT Parabola. Tuesday, April 6 (8 a.m.) Walt Snyder, Dept. of Geosciences, Boise through Wednesday, April 7 (6 p.m.). Projection equipment will be pro- State University, Boise, ID 83725, (208) David R. Lageson and David Adams, Dept. vided for 2″ × 2″ slides that fit standard 385-3645; [email protected]; Jim of Earth Sciences, Montana State Univer- 35 mm carousel trays. Two slide projec- Trexler and Pat Cashman, University of sity, Bozeman, MT 59717, (406) 994-6913, tors, an overhead transparency projector, Nevada, Reno. This symposium will cover [email protected]; Lisa Morgan and and two screens will be available. Authors not only the specifics of northeast Nevada, Ken Pierce, U.S. Geological Survey; Bob are strongly encouraged to bring their own but also the big-picture upper Paleozoic Smith, University of Utah. carousel trays. A very limited number will framework. The presentations will include This field trip will focus on new, be available in the speaker-ready room. regional aspects of the Antler and Sonoma ongoing research in structural geology, orogenies. volcanology, geophysics, and active POSTER SESSIONS Glacial and Lacustrine Records tectonics on the south side of the Snake of Late Pleistocene and Holocene Three one-half day poster sessions are River Plain. Highlights will include new Climate in the Western Interior. planned. Each poster booth will contain 40Ar/39Ar ages on hotspot-derived ignim- Glenn Thackray, Dept. of Geology, Idaho one 4′ high × 8′ wide board. brites, new thinking on large “gravity- State University, Pocatello, ID 83209, slide” blocks in the Grand Valley and (208) 236-3560, [email protected]: Gary EXHIBITS Jackson Hole, new research results on the Gianniny, Bucknell University. Late Qua- Miocene calc-alkaline Jackson Hole vol- Exhibits by businesses and education ternary climate in western North America canic field, new data on active deforma- and government institutions will be has been influenced by a variety of factors, tion of Jackson Hole (hanging wall of the adjacent to technical session rooms including orography, ice-sheet effects, and Teton normal fault), and information on at Cavanaugh’s. Exhibits will be open large-scale oceanic and atmospheric circu- the recently unveiled southeast Idaho Wednesday, 5 to 8 p.m., Thursday and lation. This symposium will examine a lineament. In addition, aspects of pre- Friday, 8 a.m. to 5 p.m., and Saturday, variety of climatic proxy records from the Neogene tectonic deformation in the 8 a.m. to noon. For further information, western interior, with the aim of elucidat- Sevier and Laramide orogenic belts will contact Joe Kruger, Dept. of Geology, Idaho ing paleoclimatic patterns across the be viewed and discussed in the context of State University, Pocatello, ID 83209-8072, region during late Pleistocene and “reactivation.” Two days (overnight stay (208) 236-3871, [email protected]. Holocene time. in Jackson). Cost: $120 (2 lunches, 1 night Zeolites and Phosphate Mineral lodging). Limit: 23. WORKSHOPS Deposits in Idaho. Mickey Gunter, 2. Teton Canyon, Mesa Falls, and Dept. of Geology and Geological Engi- ArcView GIS 3.1—Full Day. This all- the West Slope of the Teton Range, neering, University of Idaho, Moscow, ID day session on Wednesday, April 7, will Idaho-Wyoming. Tuesday, April 6 83844-3022, (208) 885-6015. This sympo- cover the fundamentals of the newest (8 a.m.–6 p.m.). Glenn Embree and Roger sium will cover a broad range of these two release of ArcView. The workshop will be Hoggan, Dept. of Geology, Ricks College, industrially important mineral groups. held in the newly constructed Idaho State Rexburg, ID 83460, (208) 356-1904. Papers will cover such aspects as crystal University GIS Lab in the basement of chemistry, mineral deposits, and applica- Graveley Hall. A shuttle van will be avail- Rocky Mountain continued on p. 20

GSA TODAY, February 1999 19 Rocky Mountain continued from p. 19 opportunity for discussion on how to cap- Paul Link and Chilton Phoenix, Idaho ture uncertainty in dating flood-plain allu- State University, (208) 236-3846, On this trip we will examine the geol- vium, soils, and landforms; uncertainty in [email protected]. ogy of the eastern end of the Snake River paleoflood discharge estimation and stable This bus tour will cover the highlights Plain, the southern flank of the Island Park channel configuration; and incorporation of the geology and history of southeastern caldera, and the western slope of the Teton of this information into flood frequency Idaho including the Lake Bonneville flood, Range, Wyoming. Emphasis will be on the analysis. Other stops will focus on parts of Red Rock Pass, Bear River Massacre site, Last Pliocene and Pleistocene bimodal volcan- the late Pleistocene soil chronosequence Chance Canal flume, Sheep Rock, and the ism of the Yellowstone–Snake River Plain developed in Big Lost River alluvium at Oregon Trail near Soda Springs. No strenu- system. Large scale (>100 m amplitude) INEEL and the implications of this ous walking. Teachers and the general pub- secondary deformation structures in the chronosequence for the timing and mag- lic are especially invited. Cost includes a Huckleberry Ridge Tuff and subjacent units nitude of glacial outburst floods. We will copy of Rocks, Rails, and Trails by Link and will be examined in detail. We will visit the also look at eolian and lacustrine deposits Phoenix. Cost: $25 (1 lunch). Limit 44. Teton Dam site and discuss the causes of its and associated soils around the Birch 8. Rocks, Rails, and Trails 2: The 1976 failure. Weather permitting, we will Creek playa, the terminus of the Big Oregon and California Trails and examine the Archean through upper Paleo- Lost River, as indicators of the maximum Hagerman Fossil Beds. Sunday, zoic rocks and Pleistocene glacial features extent of the Holocene playa and Lake April 11 (9 a.m.–7 p.m.), Paul Link and of the west slope of the Teton Range. Terreton. Cost: $50 (1 lunch). Limit: 19. Chilton Phoenix, Idaho State University, This trip may be linked with trip 3, with 5. Folded and Faulted Salt Lake (208) 236-3846, [email protected]; Greg overnight accommodations in Pocatello. Formation Above the Miocene to McDonald, Hagerman Fossil Beds Cost: $35 (1 lunch). Limit: 26. Pliocene(?) New Canyon and Clifton National Monument. 3. Cedar Butte and Cogenetic Detachment Faults, Malad and Ban- The second half of this tour for Quaternary Rhyolite Domes of nock ranges, Idaho. Wednesday, April 7 geologists, teachers, and the general public the Eastern Snake River Plain. (8 a.m.–6 p.m.). Jeffrey C. Evans and will cover the Oregon and California Trail Wednesday, April 7 (8 a.m.–6 p.m.). Susanne U. Janecke, Dept. of Geology, routes and geology through Massacre Michael McCurry, Idaho State University, Utah State University, Logan, UT 84322, Rocks, Raft River, Silent City of Rocks, (208) 236-3960, [email protected]; (435) 797-3877, [email protected]. Shoshone Falls, Perrine Bridge, Thousand Bill Hackett; Karl Hayden. Explore the complexly folded and Springs, and Hagerman Fossil Beds Quaternary rhyolites produced some faulted basin-fill deposits of the Miocene- National Monument. Lunch at Bath Rock of the most distinctive topographic and Pliocene Salt Lake Formation above two will afford an opportunity to climb to the geologic components of the Eastern Snake little-known detachment faults in the top of the rock, and sample the bathtub. River Plain. Beginning at East Butte, a northeast corner of the northern Basin Those wishing to take this climb need 0.6 Ma rhyolite dome, we will describe the and Range province. Structural features walking shoes with good tread. Cost in- petrology, geochemistry, and volcanology include extensional folds with a bewilder- cludes a copy of Rocks, Rails, and Trails by of high-silica rhyolite domes, flows, and ing range of orientations and multiple Link and Phoenix (for those not participat- pyroclastic rocks along the axial volcanic generations of normal faults. Notable ing in Part 1). Cost: $35 (1 lunch). Limit 44. zone of the area. Most of the trip will stratigraphic features include unroofing 9. The Putnam Thrust Plate, Idaho: focus on Cedar Butte volcano, a volcanic sequences and rapid rounding of quartzite Dismemberment and Tilting by Ter- center that produced a remarkably wide cobbles. The Sevier Desert detachment is a tiary Normal Faults. Saturday, April 10 spectrum of volcanic rocks, ranging from likely analog to this extensional system in (12:30 p.m.) through Sunday, April 11 basaltic trachyandesite to high-silica rhyo- age, structural setting, and overall geome- (6 p.m.). Karl Kellogg, U.S. Geological lite. We will examine key parts of the vol- try. Cost: $30 (1 lunch). Limit: 26. Survey, Box 25046, MS 913, Denver, CO cano including a rhyolite lava flow, poly- 6. Southeast Idaho Phosphate Field. 80225, (303) 236-1305, [email protected]; modal tephra cone, trachyandesite lava Wednesday, April 7 (8 a.m.–6 p.m.). David Rodgers, Mark Kiessling, and Jim flow, and compositionally zoned dikes. Ray Petrun, Solutia, Inc., Box 816, Soda Riesterer, Idaho State University; Frank Expect a long day in the field; bring boots Springs, ID 83246, (208) 547-3391, Hladky, Oregon Department of Geology for short hikes, binoculars, a camera, and ext. 341, [email protected]; and Mineral Industries. sunscreen. This trip may be linked with Al Haslam, Agrium Corporation. This trip will focus on major contrac- trip 2, with overnight accommodations in This trip into southeastern Idaho will tional structures in the hanging wall of Pocatello. Cost: $30 (1 lunch). Limit: 27. include a scenic and geologically varied the Putnam thrust and how these struc- 4. Holocene Flood History, Geomor- drive from Pocatello south down Marsh tures were modified by Neogene exten- phology, and Holocene–Late Pleis- Valley between the Portneuf and Bannock sion. The thrust system, which involves tocene Soils, Big Lost River and Ranges, then east following the Portneuf Neoproterozoic to Triassic rocks, is charac- INEEL, Idaho. Wednesday, April 7 River into Gem Valley, through the terized by multiple fault splays that may (8 a.m.–6 p.m.). Dean A. Ostenaa, Daniel R. Chesterfield Range, and into the Peale define a foreland dipping duplex. Rocks Levish, and Ralph E. Klinger, Geophysics, Mountains north of Soda Springs, Idaho. elsewhere in the thrust sheet are involved Paleohydrology, and Seismotectonics There we will tour two mines currently in a spectacular fold nappe defined by Group, D-8330, U.S. Bureau of Reclama- mining the Phosphoria Formation, a inverted and structurally thinned units. tion, P.O. Box 25007, Denver, CO 80225, world-class phosphate deposit of Permian Normal faults and tilting associated with (303) 445-3177, fax 303-445-6478, doste- age. Field trip participants will have a Basin and Range and Snake River Plain [email protected]; David T. Simpson, Wood- chance to examine and discuss several development were superimposed on the ward-Clyde Consultants; Erick A. Bestland exposed sections of the Phosphoria Forma- older thrust system, resulting in dismem- and Linda E. Mark, Idaho State University. tion and related units, as well as active berment and tilting of the contractional On this field trip we will examine the mining and reclamation operations. structures. Criteria to discriminate con- stratigraphic and geomorphic record of Cost: $30 (1 lunch). Limit 26. tractional and extensional structures will Holocene floods on the Big Lost River at be emphasized throughout the trip. Sev- Postmeeting Trips INEEL (Idaho National Engineering and eral hikes across moderately steep terrain 7. Rocks, Rails, and Trails 1: Lake Environmental Laboratory) in the context are planned. Participants will return to Bonneville Flood and the Oregon of using this information for applied Trail. Saturday, April 10 (12:30–6 p.m.), flood hazard assessment. This will include Rocky Mountain continued on p. 22

20 GSA TODAY, February 1999 Amount ______$ ______$ ______$ ______FREE FREE FREE REMITTED $______(409) $ 65 1(411) $ ______$ 55 1 ______$ TOTAL FEES TOTAL (33) $15 1 $ ______April 9 (307) $ 5 __ $ ______April 9April 9 (305) $ 12 (306) __ $ ______April 8 April 8 (201) $April 9 32 __April 9 $ (202) ______$ (203) 8 __April 7 $ ______April 10 (601) $ (602) 50 $ __ 25 __ $ April 6Ð7 ______(401) $ ______$120 1 $ ______April 11 (408)April 10Ð11 $ 35April 10 1 (410) $ April 11Ð12 ______$ 30 1 $ ______April 9 (304) April 7April 7 (405) $ 30 (406) 1 $April 10 30 $ ______1 (407) $ $ 25 ______1 $ ______. . . April 7 (404) $ 50 1 $ ______...... Beef roulades (301) $ 20 __ $ ______...... Vegetarian pastaVegetarian (303) $ 20 __ $ ______Full Meeting One Day Qty...... Chicken cordon bleu (302) $ 20 __ $ ______...... $60 (14) $40 (15) 1 $ DR CR ...... (10) $60...... (10) $40 (11) 1 $ ...... $30 (32) ...... $30 (60) $15 (61) 1 $ ...... $10 (90) 1 $ ...... $30 (30) $15 (31) 1 $ ...... FOR OFFICE USE Morning preferred Afternoon preferred Holocene Flood History, Geomorphology, Big Lost River Geomorphology, Holocene Flood History, Lake Bonneville, Oregon Trail Hagerman Fossil Beds Ore., Calif. Trails, A ______CK#______V ______M ______Bal. A/R 1233 ______Ref. A/P 2006 ______Refund ck# ______3. IAPG Luncheon 5. Spuds ‘R’ Us Millennium Bash 4. Fun Run/Walk 2. Bird Watching PREREGISTRATION FEES PREREGISTRATION Professional Member SPECIAL EVENTS 1. Annual Banquet SPECIAL ACTIVITIES 1. Horseback Riding 3. Idaho Museum of Natural History WORKSHOPS GIS 3.1 (Full Day) 1. ArcView GIS 3.1 (Half Day) 2. Introduction to ArcView FIELD TRIPS Greater Yellowstone 1. Past and Present Tectonics, Range.. Slope Teton Canyon, Mesa Falls, West 2. Teton . . April 63. Cedar Butte & Cogenetic Quaternary Rhyolite Domes . . April 7 (402) $4. 35 (403) 1 $ 30 $ ______1 $ ______9. Putnam Thrust Plate, Idaho Part 1 & Environmental Geology, Mafic Volcanism 10. Part 2 & Environmental Geology, Mafic Volcanism 11. 2. GSA Rocky Mtn. Management Board Breakfast Professional Nonmember Student Member Professional KÐ12 Guest or Spouse 5. Folded and Faulted Salt Lake Formation 6. Southeast Idaho Phosphate Field 1: Rocks, Rails, & Trails 7. 2: Rocks, Rails, & Trails 8. Student Nonmember I Pocatello, Idaho April 8–10, 1999 ⁄ fax Expires Home Phone Business Phone I ( ______) ______-______( ______) ______-______( ______) ______-______ORM F Employer/University Affiliation Mailing Address (use two lines if necessary) March 5 March Name as it should appear on your guest’s badge City State March 12 March Name as it should appear on your badge (last name first) City State or Country City State or Country ZIP Code Country (if other than USA)

Please print clearly ¥ BADGE YOUR THIS AREA IS FOR I I I I GSA ROCKY MOUNTAIN SECTION MEETING, MOUNTAIN GSA ROCKY 9140, BOULDER, CO 80301 BOX P.O. GUEST INFORMATION ¥ Please print clearly ¥ badge This area is for I I I I I Please inform us by March 10 of any Please inform us by March 10 special considerations that you or I will need special considerations. REREGISTRATION Check American Express VISA MasterCard I I I I your guest require. Remit in U.S. funds payable to: funds payable Remit in U.S. Mountain Section Meeting GSA Rocky 1999 P GSA Rocky Mountain Section Circle member affiliation: (A) GSA (B) AWG (C) NAGT (D) PS (E) SEPM Deadline: Preregistration Cancellation Deadline: MAIL TO: be prepaid. must (All preregistrations Purchase Orders not accepted.) Payment by (check one): I Card Number I Signature

GSA TODAY, February 1999 21 Rocky Mountain continued from p. 20 logical and touring sites within 0–3 hours’ cial state-supported museum located on drive include Yellowstone National Park, the Idaho State University campus and to Pocatello for Saturday night lodging and Jackson Hole, the Teton Range, Menan see some of the sites around the campus. meals, which are not included in the trip Buttes, Silent City of Rocks, Craters of the cost. Cost: $65 (2 lunches). Limit: 20. Moon National Monument, Sun Valley, STUDENT TRAVEL SUPPORT 10. Mafic Volcanism and Environ- Lava Hot Springs, Idaho Museum of Natu- mental Geology of the Eastern The GSA Rocky Mountain Section has ral History, and Shoshone-Bannock Native Snake River Plain, Part 1. Saturday funds to support travel to the meeting for American Reservation. afternoon, April 10 (12:30–6 p.m.). Scott students. Please submit requests to Ken Horseback Riding, Thursday, April 8, Hughes, Idaho State University, (208) Kolm, Div. of Environmental Science and Group 1 (morning) and Group 2 (after- 236-4387, [email protected]; Bill Hackett, Engineering Dept., Colorado School of noon); indicate which group is desired. WRH Consultants; Dick Smith, Lockheed- Mines, Golden, CO 80401, kkolm@mines. Transportation to and from Cavanaugh’s Martin Idaho Technologies Corporation; colorado.edu. Applications must be and a snack will be provided. Mini- John Welhan, Idaho Geological Survey. received by February 1, 1999. mum: 4; maximum: 7. Cost: $32. Part 1 highlights Quaternary basaltic fis- Bird Watching, Friday, April 9, 7 a.m.– sure eruptions that produced coalescent DETAILED INFORMATION noon. Chuck Trost, professor, Idaho State monogenetic shields, and phreatomag- University Department of Biological Sci- Other information concerning matic eruptive centers that produced tuff ences, will show participants viewing sites registration, lodging, activities, and the cones and rings. Field stops will be at the for shorebirds and birds of prey within program will be provided in the Rocky Holocene Hells Half Acre lava field and the easy driving distance from Pocatello. Mountain Section Abstracts with Programs. late Pleistocene Menan Buttes tuff cone Transportation to and from Cavanaugh’s Address general questions to Scott Hughes, complex. Discussion will focus on the con- and lunch will be provided. Cost: $8. Idaho State University, (208) 236-4387, struction of these volcanoes and the rela- Idaho Museum of Natural History, [email protected]; or visit our Web site at tion of eastern Snake River plain volcan- Friday, April 9, 2–4:30 p.m. This FREE out- http://wapi.isu.edu/rm-gsa99, for addi- ism to the adjacent Basin and Range ing will allow participants to visit the offi- tional details and information updates. ■ province. A no-host optional evening ses- sion with food and beverages is planned. Cost: $30 (1 lunch). Limit: 26. 11. Mafic Volcanism and Environ- ORDER FORM—1999 GSA Abstracts with Programs mental Geology of the Eastern To purchase copies of GSA Abstracts with Programs, you may use this form. Prepayment Snake River Plain, Part 2. Sunday, is required. Members, provide member number and deduct your 20% discount. April 11 (8 a.m.) through Monday, Check your records to make sure you have not previously purchased any of these publications April 12 (6 p.m.). Scott Hughes, Idaho on your dues statement, or through Publication Sales. No refunds for duplicate orders. State University, (208) 236-4387, hugh- [email protected], Bill Hackett, WRH Consul- List Meeting Meeting Dates Price Quantity Amount tants; Dick Smith, Lockheed-Martin Idaho Technologies Company; Steve Anderson, South-Central 3/15–3/16 $15 $ U.S. Geological Survey. Northeastern 3/22–3/24 $15 $ Part 2 emphasizes Quaternary mafic Southeastern 3/25–3/26 $15 $ volcanism on the axial volcanic zone and the Great Rift, dike-induced structures, Rocky Mountain 4/8–4/10 $15 $ phreatomagmatic eruptions, surficial pro- North-Central 4/22–4/23 $15 $ cesses, hydrogeology, and glacial cata- Cordilleran 6/2–6/4 $15 $ clysmic flooding. Field stops will illustrate Annual Meeting (Denver) 10/25–10/28 $38.75 $ inflationary lava flow emplacement, basaltic shield growth, and fissure systems Check here if GSA Member Total $ represented at several monogenetic lava Members deduct 20%. It will not be applied later. ➝ –20% $ fields. We will also visit Craters of the Member # ______TOTAL $ Moon lava field, a polygenetic and compo- sitionally evolved eruptive system along SHIP TO: the northern end of the Great Rift, and the Name ______Massacre volcanic complex, a sequence of basaltic tuffs and lava flows representing Address ______several phreatomagmatic vents along the Address ______Snake River. Participants will return to Pocatello for Sunday night lodging and City______State ____ ZIP ______Daytime Phone ______meals, which are not included in the trip cost. A no-host optional evening session METHOD OF PAYMENT: with food and beverages is planned. CHECK or MONEY ORDER (payable in U.S. funds on U.S. bank) Cost: $55 (2 lunches). Limit: 26. Credit Card (Please print information) MC VISA AmEx Diners (circle one) Exp. Date ______SPECIAL ACTIVITIES Card No. ______Special activities are primarily offered for spouses and friends of meeting partici- Signature of Cardholder ______pants; however, they are not exclusive to TO ORDER BY MAIL: Send this form to GSA Publication Sales, P.O. Box 9140, Boulder, CO 80301-9140 meeting participants. Preregistration is sug- gested to get a head count. Besides the list TO ORDER BY PHONE OR FAX using a major credit card below, there are many opportunities for fax (24-hour line): 303-447-1133; or phone (303) 447-2020 or 1-800-472-1988 (8:00 a.m. to 4:30 p.m. MT) family activities and travel in southeastern ON-SITE PURCHASES may be made in the registration area at each meeting. Supplies are limited. Idaho and surrounding areas. Popular geo-

22 GSA TODAY, February 1999 Final Announcement March 19, 1999, will be charged the on- site rate. Early registration is strongly recom- NORTH-CENTRAL SECTION, GSA mended for all field trips, workshops, and 33rd Annual Meeting special activities because of limits on the number of participants. Champaign, Illinois ★ Registration badges must be worn for April 22–23, 1999 access to all activities. Guest registration is required for attendance at the welcoming party, annual dinner, scheduled lun- cheons, and field trips. Guest rates are he Illinois State Geological Survey, Department of Geology at the available for persons accompanying a pro- University of Illinois in Champaign-Urbana, and the U.S. Geological fessional, student, or K–12 professional Survey Water Resources Division—Urbana, Illinois Office will host the 33rd T registered for the meeting. Annual Meeting of the North-Central Section of the Geological Society of America. A current student ID is required to The meeting will be held at the Clarion Hotel and Convention Center in Champaign. obtain student registration rates. Students Societies and organizations meeting with the North-Central Section include the Associa- who cannot produce a current student ID tion for Women Geoscientists, Central Section of the National Association of Geoscience when they pick up their registration mate- Teachers, Great Lakes Section of SEPM, and North-Central Section of the Paleontological rials will be charged the full professional Society. These organizations welcome you to Champaign-Urbana for two full days of sci- registration fee. entific exchange, plus field trips and workshops. The Abstracts with Programs book may be purchased with your GSA membership SETTING culture, and opportunities in Champaign- renewal, or on site in the registration area. Urbana. Members pay less! You can join Champaign-Urbana (population now or at the meeting. Come visit the 100,000), home of the main campus of the REGISTRATION GSA Membership Services area for new University of Illinois, is situated in east- member applications, reinstatements, central Illinois on a landscape consisting Registration is required for all who dues payment, address changes, questions, of broad, low end moraines and till plains participate in any event at the meeting, or concerns. Contact GSA for further formed during the retreat of the Wiscon- including technical sessions, symposia, information. sin Episode glacier some 17,000 years ago. workshops, field trips, exhibits, and Access. The GSA North-Central Sec- This glacial terrane is the setting for some planned social events. tion is committed to making all events at of the world’s richest farmland. Cham- the 1999 meeting accessible to all people paign-Urbana lies within the northern Preregistration deadline: interested in attending. The Clarion Hotel part of the Illinois Basin, a mineral-rich March 19, 1999 and Convention Center complies with all cratonic basin underlying much of Illinois Preregistration is encouraged to aid ADA requirements. If you have special and adjacent parts of Indiana and Ken- local committees in making final plans requirements of any kind, please indicate tucky. The University of Illinois campus for the meeting. A discount is available to this on the registration form or call Den- is recognized widely as a major center for those who preregister by using the form nis R. Kolata at (217) 244-2189. We will computing and technology and is a leader provided in this announcement. Preregis- be happy to make whatever arrangements in building the national and global infor- tration is required for field trips and we can to enable full participation in the mation superhighway. Visit our Web site workshops. Return the registration meeting. If possible, please let us know by (http://www.isgs.uiuc.edu/isgshome/fra1. form provided herein with full March 19, 1999, so that we will have time html) to learn more about the history, payment by check or credit card to to make any necessary arrangements. the Geological Society of America CANCELLATIONS, CHANGES, AND North-Central Meeting, P.O. Box REFUNDS 9140, Boulder, CO 80301-9140. Full MARK YOUR All requests for registration additions, payment MUST accompany registration. changes, and cancellations must be made CALENDAR! Please preregister only one professional, in writing and received by March 26, 1999. one student, or one K–12 professional per Shlemon mentors will be presenting Faxes to 303-447-0648 or 303-447-1133 form. Guests preregistering for the meet- one-day workshops during the GSA will be accepted. Advance registrations ing may register on the same form. A con- Northeastern, North-Central, and will be refunded for all such cancellations. firmation letter from GSA will be your Cordilleran section meetings for receipt. Preregistration forms received after graduate and senior undergraduate North-Central continued on p. 24 geology students on opportunities and challenges in applied geosciences. Northeastern Section REGISTRATION FEES March 21, 1999 Advance* On-Site North-Central Section Full meeting One day Full meeting One day April 24, 1999 Professional Member $65 $40 $75 $50 Cordilleran Section Professional Nonmember $70 $45 $80 $55 to be announced Student Member $30 $15 $35 $20 For more information, please contact Student Nonmember $35 $25 $40 $30 Stacey Ginsburg at (303) 447-2020, K–12 Professional $25 $30 ext. 194, or e-mail sginsburg@ Guest or Spouse $10 $15 geosociety.org. *By March 19, 1999

GSA TODAY, February 1999 23 North-Central continued from p. 23 2. Studies in Hydrogeology. uiuc.edu, and B. Brandon Curry (217) A. Characterizing Agricultural Impacts 244-5787, [email protected], Illinois NO REFUNDS WILL BE MADE ON CAN- on Shallow Groundwater Quality. State Geological Survey. CELLATION NOTICES RECEIVED AFTER Edward Mehnert, (217) 244-2765, C. The Importance of Geologic Mapping MARCH 26, 1999. Refunds paid by credit [email protected], and William S. for Environmental Studies. Richard C. card will be credited according to the card Dey, (217) 244-2779, fax 217-244-2785, Berg, (217) 244-2776, fax 217-333- number on the preregistration form. NO [email protected], Illinois State Geo- 2830, [email protected], Illinois State refunds will be given for on-site registra- logical Survey. Geological Survey. tion or ticket sales. B. Modeling Geologic Environments for D. Geologic Mapping in Glaciated Areas: Hydrogeologic Applications. Advances and Applications (Posters). ON-SITE REGISTRATION Donald A. Keefer, (217) 244-2786, Barbara J. Stiff, (217) 244-2510, fax 217- SCHEDULE [email protected], and David R. 333-2830, [email protected], Registration will be held in the lobby Larson, (217) 244-2770, fax 217-244- Illinois State Geological Survey; of University Hall at the Clarion Hotel and 2785, [email protected], Illinois Peter T. Lyttle, (703) 648-6943, Convention Center. Registration hours are: State Geological Survey. fax 703-648-6937, [email protected], Wed., April 21 ...... 4:30 to 9 p.m. C. Chemical and Isotopic Studies U.S. Geological Survey, Reston. Thurs., April 22 . . . 7:30 a.m. to 4:30 p.m. of Groundwater. Keith C. Hackley, 8. Tectonics and Seismicity in the Fri., April 23 ...... 7:30 a.m. to noon. (217) 244-2396, fax 217-244-2785, Midcontinent U.S. John H. McBride, [email protected], Illinois State (217) 333-5107, fax 217-333-2830, STUDENT PAPER AWARDS AND Geological Survey; Thomas M. John- [email protected], Illinois State TRAVEL ASSISTANCE GRANTS son, (217) 244-2002, fax 217-244-4996, Geological Survey. The North-Central Section of GSA will [email protected], University of Illi- 9. Economic Geology of Mineral and award $100 each for up to eight papers nois. Energy Resources of the Midconti- judged best in their respective technical D. Innovative Field Techniques and nent United States. Subhash B. Bhag- session. The principal author and presen- Equipment (Posters). Edward Mehnert, wat, (217) 333-7409, fax 217-333-2830, ter must be a graduate or undergraduate (217) 244-2765, fax 217-244-2785, [email protected], Illinois State Geo- student. Abstracts of papers submitted for [email protected], Illinois State logical Survey. consideration for these awards should be Geological Survey. A. Construction Aggregates and Associ- so indicated on the abstract form. 3. Functional Morphology and ated Minerals. Grants for travel assistance of up to Paleobiology of Extinct Vertebrates B. Industrial Minerals Other Than Con- $200 (exclusive of field trip fees) are avail- (Sponsored by North-Central Section of the struction Aggregates. able to student members and associates of Paleontological Society). James Farlow, C. Fossil Fuels and Associated Minerals. GSA. The assistance will be offered on a (219) 481-6251, fax 219-481-6880, D. Economics of Groundwater first-come, first-served basis, with priority [email protected], Indiana University/ Resources. given to students presenting oral or poster Purdue University at Fort Wayne, Fort 10. Outreach: A Necessity for Our papers. To be eligible for travel assistance Wayne, IN 46805-1499. Profession (Sponsored by Central Section grants, students must be currently 4. Heinz A. Lowenstam Symposium of the National Association of Geoscience enrolled in an academic department and on the Silurian System of the Cen- Teachers). Myrna M. Killey, (217) 244-2409, certify their student membership in GSA. tral United States. Donald G. Mikulic, [email protected], and Janis D. Treworgy, Applications for travel assistance grants (217) 244-2518, fax 217-333-2830, (217) 244-6942, [email protected], may be obtained from Jay D. Bass, Dept. [email protected], Illinois State Illinois State Geological Survey, fax 217- of Geology, University of Illinois, 1301 Geological Survey; Joanne Kluessendorf, 333-2830. W. Green St., Urbana, IL 61801-2999, (217) 367-5916, fax 217-244-4996, A. Oral Session. (217) 333-3542, fax 217-244-4996, [email protected], University of Illinois. B. Poster Session—Hands-On and High- [email protected]. Applica- 5. Paleozoic Environments of the Tech Activities: Making Geoscience tions for travel assistance must be received Midcontinent United States (Sponsored Readily Understandable. no later than March 12, 1999. by Great Lakes Section of SEPM). Bruce W. 11. Geoarchaeological Burial Proc- Fouke, (217) 244-5431, fax 217-244-4996, esses. Donald L. Johnson, (217) 333-0589, TECHNICAL PROGRAM [email protected], Dept. [email protected], Dept. of Geography, of Geology, University of Illinois, 1301 W. University of Illinois, 220 Davenport Hall, Questions regarding the technical Green Street, Urbana, IL 61801-2999; Urbana, IL 61801; E. Arthur Bettis III, program should be addressed to C. Pius Zakaria Lasemi, (217) 244-6944, fax 217- (319) 335-1578, [email protected], Weibel, North-Central Section Program 244-2785, [email protected], Illinois University of Iowa. Coordinator, Illinois State Geological Sur- State Geological Survey. 12. Midwestern Geologists: Late 19th vey, 615 E. Peabody Dr., Champaign, IL 6. Coastal Geology in the Great Century–Early 20th Century. Ralph L. 61820, [email protected]. Technical Lakes Region: Accomplishments of Langenheim, Jr., (217) 333-1338, fax 217- sessions will begin at 8 a.m. on Thursday, the 20th Century: Challenges for the 244-4996, [email protected], Dept. April 22, 1999, and will conclude at 5 p.m. 21st Century. Michael J. Chrzastowski, of Geology, University of Illinois, 1301 W. on Friday, April 23, 1999. (217) 244-2194, fax 217-244-0029, Green St., Urbana, IL 61801-2999. Symposia [email protected], Illinois State 13. Is “Geology and Public Policy” Note: Illinois State Geological Survey address Geological Survey. Just Another Oxymoron? Thomas J. is 615 E. Peabody Dr., Champaign, IL 61820. 7. Geologic Mapping in Glaciated Areas. Evans, (608) 263-4125, fax 608-262-8086, 1. Karst Hydrology and Associated A. Great Lakes Coalition on Geologic [email protected], Wisconsin Geo- Water Quality in the Midcontinent. Mapping in Glaciated Areas. logical and Natural History Survey, 3817 Samuel V. Panno, (217) 244-2456, William W. Shilts, (217) 333-5111, Mineral Point Rd., Madison, WI 53705. [email protected], and C. Pius Weibel, fax 217-244-7004, [email protected], (217) 333-5108, fax 217-244-2785, Illinois State Geological Survey. PROJECTION EQUIPMENT [email protected], Illinois State Geolog- B. Nature of the Sediment Record and Two standard 35 mm carousel pro- ical Survey. How It Affects Mapping. Ardith K. jectors for 2″ × 2″ slides and two viewing Hansel, (217) 333-5852, hansel@isgs.

24 GSA TODAY, February 1999 screens will be provided in each meeting Archer, (785) 532-2244, [email protected], grades 4–8, pre-service teachers, and oth- room. An overhead projector for trans- Kansas State University; Norman C. Hes- ers who work with upper elementary and parencies will be available for each room ter, Indiana University, Bloomington. secondary teachers and students. Partici- as well. A speaker-ready room equipped This one-day course will focus on pants will receive classroom materials with projectors will be available for review the recognition, depositional setting, and including recent posters, maps, slide sets, of slides and overheads and for speaker significance of modern and ancient tidal activity workbooks, and much more. Sat- preparation. Each carousel to be used in rhythmites. Tidal rhythmites consisting of urday, April 24, 1999, 8 a.m. to 5 p.m., an oral presentation should be clearly very thin to thickly laminated sediments Grange Room, Clarion Hotel and Conven- identified with the speaker’s name, session that preserve distinct tidal periodicities are tion Center, $10 (includes lunch). number, and speaker number. Carousels known from a variety of modern (meso- 3. Introduction to Geographic Infor- must be turned in to the projectionists at to macrotidal) and ancient (Precambrian, mation Systems: Applications for the beginning of the appropriate technical Paleozoic, and Cretaceous) depositional Geologic Mapping. Robert J. Krumm, session. settings. Many examples of ancient tidal (217) 333-4085, fax 217-333-2830, Speakers are encouraged to load slides rhythmites have been found in succes- [email protected], Illinois State in their own carousels. A few carousels will sions once thought to have been totally Geological Survey, 615 E. Peabody Dr., be available for loan to those unable to nonmarine. Thus, their recognition has Champaign, IL 61820. supply their own, but these will be loaned obvious implications for the understand- This workshop will be targeted at peo- out on a first-come, first-served basis and ing of depositional environments and ple who are either just beginning to work must be returned to the speaker-ready paleogeography. with GIS or are still looking at GIS. It will room immediately following the technical Exercises and discussions will range provide an introduction to basic concepts, session in which they are used. from physical (cores and slabs) to analyti- issues, and acronyms, and in particular, cal (time-series, geochemical, geophysical will focus on the use of GIS to support POSTER SESSIONS log, and petrological analyses). Techniques geologic mapping activities. The workshop will be presented for studying tidal rhyth- Students and professionals are will not include hands-on instruction, but mites, their depositional context, the encouraged to take advantage of this effec- we will present a number of on-line soft- recognition of astronomically forced tidal tive means of presentation. Please indicate ware demonstrations. We will present an cycles, and the application of tidal, rhyth- poster session on the GSA abstract form. overview of GIS technology including soft- mite-bearing facies to sequence stratigra- Each poster booth will contain two ware, hardware, and digital databases. We phy, basin analysis, paleoclimatology, and attached panels, each 4 × 4 feet, made of will provide information on no-cost and paleoastronomy. Discussions will also soft particle board and arranged at table low-cost software and data, as well as include the economic implications of the height. Poster sessions will be in the Internet GIS applications, including how occurrence of tidal rhythmites and associ- Alumni Room of the Clarion Hotel and to find on-line databases and how to serve ated facies to the exploration and produc- Convention Center. Posters will be avail- maps on the World Wide Web. In addi- tion of energy resources (hydrocarbons able for viewing for four hours during tion, we are prepared to address other spe- and coal). Specifically, we will discuss each session. cific topics, and we welcome input from what the recognition of tidal, rhythmite- Special Poster Session on Under- those attending the workshop. If you have bearing facies implies regarding sandstone graduate Research (Sponsored by the specific ideas or suggestions for topics that geometries and architecture within estuar- Geology Division of the Council on Under- you would like to see addressed in this ine and tide-dominated deltaic systems as graduate Research). These posters, written workshop, please contact Robert Krumm. well as their association with freshwater and presented by undergraduate students, Saturday, April 24, 1999, 9 a.m. to 4 p.m., deposits such as low-sulfur coals. Formal will form a separate poster session or be Illinois State Geological Survey, Confer- presentations by the instructors will be part of another poster session, depending ence Room (Room 101), $35 (includes combined with group exercises and discus- on the response. Co-authored papers for lunch). sions utilizing cores, geophysical logs, and which the student is senior author will slabs. Wednesday, April 21, 1999, 8 a.m. 4. Roy Shlemon Mentors in Applied also be considered. Undergraduate stu- to 5 p.m., Patio Room, Clarion Hotel and Geology Program: Workshop for dents who have been involved in research Convention Center; $45 for students Students (Sponsored by the Institute for are strongly urged to submit abstracts on (includes course notes, lunch, two coffee Environmental Education). This program their research projects, activities, tech- breaks; does not include SEPM Tidal brings experienced geologists currently niques, and/or preliminary results. For Rhythmite poster); $67 for professionals practicing in various fields of applied geol- additional information, contact Robert D. (includes course notes, lunch, two coffee ogy (Mentors) together with graduate and Shuster, (402) 554-2457, fax 402-554-3518, breaks, and SEPM Tidal Rhythmite poster). advanced undergraduate geology students [email protected], Dept. of for a one-day workshop that focuses on Geography-Geology, University of 2. Exploring the Solar System in the professional opportunities and challenges Nebraska at Omaha, Omaha, NE 68182. Classroom: Hands-On Approach. in the applied geosciences. Thomas A. Cassandra R. Coombs, (803) 953-8279, Prickett, internationally known consulting WORKSHOPS [email protected], Dept. of Geology, groundwater hydrologist, will present the College of Charleston, 58 Coming St., Preregistration is encouraged so that workshop. There is no charge to students; Charleston, SC 29424; Eileen Herrstrom, organizers may prepare adequate numbers however, preregistration is required as (217) 244-6172, fax 217-244-4996, of printed materials. Additional informa- space may be limited. Use the registration [email protected], University of Illinois. tion can be obtained from the organizers, form included in this announcement. Have you ever wondered what whose names and addresses are given Saturday, April 24, 1999, 8 a.m. to 5 p.m., another planet’s surface looked like, or below. Champaign-Krannert-Urbana Rooms, how it formed? Come explore our solar 1. Great Lakes Section—SEPM Short Clarion Hotel and Convention Center; system in a fun-filled, action-packed, day- Course—Tidal Rhythmites. Erik P. no charge; includes lunch. long workshop. We will use numerous Kvale (812) 855-1324, [email protected], hands-on activities to explore geologic and Maria Mastalerz (812) 855-9416, fax processes that operate on Earth and on 812-855-2862, [email protected], other bodies in our solar system. Work- Indiana Geological Survey, 611 Walnut shop activities are targeted at teachers of Grove, Bloomington, IN 47405; Allen W. North-Central continued on p. 26

GSA TODAY, February 1999 25 North-Central continued from p. 25 (573) 882-3231, geosccw@showme. the price difference is just the cost of the missouri.edu, University of Missouri, motel (double occupancy). Cost: $115. FIELD TRIPS Columbia; James E. Vandike, (573) Plan B. Depart from Super 8 Motel 368-2194, Missouri Department of Natural in St. Charles, Illinois on Saturday, Field trip coordinators are Janis D. Resources, Division of Geology and Land April 24, at 7:45 a.m. and return to Treworgy (217) 244-6942, [email protected]. Survey. Super 8 by 5 p.m. Cost: $75. edu, and Myrna M. Killey (217) 244-2409, Classic karst terrains, replete with fax 217-333-2830, [email protected], 4. Silurian Depositional Environ- large, closely spaced sinkholes, extensive Illinois State Geological Survey, 615 E. ments and Sequence Stratigraphy cave systems, and large springs await the Peabody Dr., Champaign, IL 61820. All of the Northern Edge of the Illinois participant. Compare and contrast the inquiries about field trip arrangements Basin. Donald G. Mikulic, (217) 244-2518, landscapes of the Illinois loess-covered, should be directed to Janis Treworgy. All fax 217-333-2830, [email protected], Mississippian limestones with Missouri’s trips begin and end at the east entrance to Illinois State Geological Survey, 615 E. thinly covered, Ordovician dolomites that the Clarion Hotel and Convention Center, Peabody Drive, Champaign, IL 61820; bound the Mississippi River valley. Explore 1501 South Neil St., Champaign, IL 61820. Joanne Kluessendorf, (217) 367-5916, fax the well-decorated, branch-work labyrinth Parking is available at the hotel. Trip 217-244-4996, [email protected], Univer- of Illinois Caverns. Investigate a cave charge includes van or coach transporta- sity of Illinois. spring that becomes a picturesque water- tion, double occupancy lodging on We will visit classic exposures in fall as it plunges 50 feet down a tufa- overnight trips, guidebook, meals, and northeastern Illinois that have played an encrusted, limestone bluff. Discover why snacks (except as indicated for each trip). important role in determining the Silurian 60% of all wells drilled in the Illinois sequence stratigraphy and depositional sinkhole plain produce undrinkable water. Premeeting history of the region. Taking advantage Prepare to experience karst geology and 1. Glacial Sediments, Landforms, of the extensive quarry exposures, we will hydrogeology from the surface and subsur- Paleosols, and a 20,000-Year-Old examine the entire Silurian section. The face, and don’t forget your hiking boots, Forest Bed in East-Central Illinois. Thornton reef, which is one of the best- hard hat, and flashlight. Ardith K. Hansel,(217) 333-5852, exposed Paleozoic reefs in the world, will Depart Saturday, April 24, at 7 a.m. [email protected], and Richard C. Berg, be highlighted. Many seminal concepts of (no breakfast included) and return Sunday, (217) 244-2776, [email protected], reef paleoecology were formulated at this April 25, by 6 p.m. Cost: $150. Illinois State Geological Survey, 615 E. reef by Heinz Lowenstam and others. Peabody Drive, Champaign, IL 61820, 3. Quaternary Geology, Geomorphol- Understanding reef growth there has aided fax 217-333-2830; Vince Gutowski, (217) ogy, and Climatic History of Kane the economic development of the aggre- 581-3825, [email protected], Eastern County, Illinois. B. Brandon Curry, gate and petroleum industries in the Great Illinois University. (217) 244-5787, [email protected], Lakes area. We will traverse classic Wisconsin and David A. Grimley, (217) 244-7324, Depart Friday, April 23, at 6:30 p.m. Episode end moraines, till plains, and lake [email protected], Illinois State (after dinner) and return Saturday, plains from Champaign southward to the Geological Survey, 615 E. Peabody Dr., April 24, by 7:30 p.m., with a dinner stop Shelbyville moraine and make a brief loop Champaign, IL 61820, fax 217-333-2830; en route (not included in cost). Cost: $85. beyond the moraine to view the more dis- Jay Stravers, (815) 753-7927, fax 815- 5. Neotectonics of the Southern sected Illinoian till plain. En route, we will 753-1945, [email protected], Northern Illinois Basin. W. John Nelson, (217) visit Charleston Quarry, where a buried Illinois University. 244-2428, fax 217-333-2830, jnelson@ 20,000-year-old forest rooted in the Farm- We will use a multidisciplinary isgs.uiuc.edu, Illinois State Geological dale Geosol overlies the last interglacial approach to understand the Quaternary Survey, 615 E. Peabody Drive, Champaign, soil. Depressions in the Farmdale Geosol geology and landforms of Kane County, IL 61820; Richard W. Harrison, (703) (mastodon footprints?) will be examined, a rapidly developing area west of Chicago. 648-6928, [email protected], U.S. Geologi- as well as proglacial lacustrine, fluvial, and We will examine the sedimentary facies of cal Survey, Reston; David Hoffman, (573) subaqueous flow deposits beneath sub- four glacigenic diamicton units and sorted 368-2144, [email protected], glacial till that contains sand lenses and sediment, and relate these units to recent Missouri Department of Natural Resources. bodies (deformed subglacial channel 1:24,000-scale mapping. Of special interest This two-day trip will highlight Qua- fills?). After lunch at Fox Ridge State Park, are (1) an interstadial deposit that con- ternary tectonic faulting just north of the where a series of ravines in the Shelbyville tains 15,000-year-old seeds, leaves, ostra- active New Madrid seismic zone in south- moraine can be seen, we will visit Tuscola codes, and molluscs that lived under tun- eastern Missouri and southern Illinois. We Quarry, where deposits of three glacial dra conditions, (2) several 25,000-year-old will visit trenches and stream banks that episodes and four nonglacial episodes are spruce tree stumps in the Farmdale Geosol display multiple episodes of deformation exposed. Mapping techniques in terrain above the Sangamon Geosol, and (3) the ranging from early Tertiary through with few exposures will be discussed at late glacial and postglacial climatic history Holocene. These findings demonstrate this stop. and paleohydrology of Nelson Lake. We that tectonic activity has occurred in dif- Depart at 8 a.m. on Wednesday, will stop at the threatened spring-fed trout ferent regions of the northern Mississippi April 21, and return by 4:30 p.m. Hard ponds of Fisherman’s Inn and traverse sev- embayment area at various times during hats required at quarry stops. Cost: $45. eral moraines, the Kaneville esker, ice-stag- the Quaternary. The New Madrid seismic nation topography, lake basins, outwash zone is only the most recent manifestation Postmeeting channels, and the gorgeous Fox River of this activity. 2. Geology, Hydrology, and Water Valley. Depart Friday, April 23, at 5:30 p.m. Quality of the Karst Regions of Plan A. Depart from Champaign on (includes dinner en route) and return Southwestern Illinois and South- Friday, April 23, at 5:30 p.m. and return to Sunday, April 25, by 5 p.m. Cost: $170. eastern Missouri. Samuel V. Panno, Champaign Saturday, April 24, by 9:30 p.m. (217) 244-2456, [email protected], and Dinner both nights is en route, but not 6. Depositional Facies and Sequence C. Pius Weibel, (217) 333-5108, weibel@ included in trip cost. If you drive your Stratigraphy of the Middle Mississip- isgs.uiuc.edu, Illinois State Geological Sur- own car to St. Charles and wish to lodge pian Warsaw Shale and Salem, St. vey, 615 E. Peabody Dr., Champaign, IL with the group, please register for Plan A; 61820, fax 217-244-2785; Carol Wicks, North-Central continued on p. 28

26 GSA TODAY, February 1999 Amount ______1 $ ______1 $ ______1 $ ______FREE FREE FREE REMITTED $______TOTAL FEES TOTAL April 22April 22 (302) $April 23 12 __ (303) $April 23 22 $ ______(304) $ 10 $ ______(305) $ ______April 21 $67 Professional (601) __Student______$ $ (601) 45April 24 __April 24 $ ______(603) $ 35 __ (604) $ ______April 21April 24Ð25 $ (401) (402) $150 45 1 $ 1 Plan A ______$ ______Plan B (403) $115 1 (404) $April 23Ð25 $ 75 ______(406) $170 1 April 24Ð25 1 $ (407) $ 125 ______$ ______1 $ ______April 23 (306) $ 11 __ $ ______...... (32) $35(60) $25(90) $10 (33) $25 1 $ ______1 $ 1 ______$ ______(30) $30 $15 (31) 1 $ ______Full Meeting One Day Qty...... $70 (14) $45 (15) 1 $ ...... (10) $65...... (10) $40 (11) 1 $ ...... DR CR ...... FOR OFFICE USE Member fee applies to any current Professional OR Student of GSA or Associated Societies listed at left. Discount does not apply to guest registrants. A ______CK#______V ______M ______Bal. A/R 1233 ______Ref. A/P 2006 ______Refund ck# ______PREREGISTRATION FEES PREREGISTRATION Professional Member* * SOCIAL EVENTS 1. GSA N-C Section Management Board Breakfast . . . April 223. Annual Banquet (301) Breakfast 4. AWG 5. GSA N-C Campus Reps Breakfast WORKSHOPS 1. GL Section SEPM Course—Tidal Rhythmites 2. Exploring the Solar System: Hands-On Approach . . April 243. Intro to Geographic Information Systems 4. Roy Shlemon Mentors Program (602) $ 10 __ $ FIELD TRIPS ______1. Glacial Sediments, Landforms, Paleosols Quality—Karst Regions Water Hydrology, 2. Geology, . . 3. Quaternary Geol., Geomorphol., Climate History . . . April 24 4. Silurian Depositional Environments, Illinois Basin . . . April 235. Neotectonics of the Southern Illinois Basin 6. Depositional Facies, Sequence Stratigraphy (405) $ 85 1 $ ______2. Paleontological Society/SEPM Luncheon 6. NAGT Luncheon KÐ12 Professional KÐ12 Guest or Spouse Professional Nonmember Student Member* Student Nonmember I April 22–23, 1999 ⁄ fax Expires Home Phone Business Phone Champaign-Urbana, Illinois I ( ______) ______-______( ______) ______-______( ______) ______-______ORM F Employer/University Affiliation Mailing Address (use two lines if necessary) March 19 March Name as it should appear on your guest’s badge City State March 26 March Name as it should appear on your badge (last name first) City State or Country City State or Country ZIP Code Country (if other than USA)

Please print clearly ¥ BADGE YOUR THIS AREA IS FOR GSA NORTH-CENTRAL SECTION MEETING GSA NORTH-CENTRAL 9140, BOULDER, CO 80301 BOX P.O. I I I I

GUEST INFORMATION ¥ Please print clearly ¥ badge This area is for I I I I I Please inform us by March 19 of any Please inform us by March 19 special considerations that you or (A) GSA (B) AWG (C) NAGT (D) PS (E) SEPM I will need special considerations. REREGISTRATION I I I I your guest require.

P GSA North-Central Section Circle member affiliation (to qualify for registration discount): Deadline: Preregistration Cancellation Deadline: MAIL TO: to: funds payable Remit in U.S. GSA North-Central Section Meeting 1999 be prepaid. must (All preregistrations Purchase Orders not accepted.) Payment by (check one): CheckI Card Number American Express VISAI Signature MasterCard

GSA TODAY, February 1999 27 North-Central continued from p. 26

Louis, and Ste. Genevieve Limestones in Western Illinois. Zakaria Lasemi, (217) 244-6944, [email protected]; Rodney D. Norby, (217) 244-6947, [email protected]; Joseph A. Devera, (618) 985-3394, [email protected]; and Hannes E. Leetaru, (217) 333-5058, [email protected], Illinois State Geological Survey, 615 E. Peabody Dr., Champaign, IL 61820, fax 217-244-2785; Bruce W. Fouke, University of Illinois at Urbana-Champaign. This trip will focus on the deposi- tional facies of the middle Mississippian (Meramecian) formations as seen in road- cuts and quarries in the East St. Louis area of Illinois. We will discuss litho- and bios- tratigraphic relationships, examine oolitic shoals and the shoaling-upward cycles within the Salem and Ste. Genevieve Limestones, analyze sequence stratigraphic relationships, present the regional struc- tural picture, examine faults, and discuss depositional facies in relation to limestone resources and hydrocarbon reservoirs. Depart Saturday, April 24, at 7 a.m. (no breakfast included) and return Sunday, CHAMPAIGN-URBANA April 25, by 5 p.m. Hard hats required at REA APS quarry stops. Cost: $125. A M

BUSINESS MEETINGS AND (cost: $10). Preregistration is SOCIAL EVENTS required for both. All special events and business meet- A luncheon will be held at ings will be held at the Clarion Hotel and noon Friday, April 23, in the Patio Convention Center. A Welcoming Rooms for the Central Section Reception will be held on Wednesday of the National Association evening, April 21, 1999, 6 to 8:30 p.m., of Geoscience Teachers. in the Alumni Room. Cost: $11. The GSA North-Central Section Management Board will hold its busi- SPECIAL ACTIVITIES ness meeting with breakfast on Thursday AND EVENTS morning, April 22, 1999, in the Skylight Alternative opportunities for Room, beginning at 7 a.m. registrants and guests will be The North-Central Section of available during the meeting, including ACCOMMODATIONS the Paleontological Society and the informally organized and hosted trips to Great Lakes Section of SEPM will A large block of rooms has been sites of interest in the Champaign-Urbana meet jointly for lunch at noon on Thurs- reserved at the Clarion Hotel and Conven- area. Registration is not required for these day, April 22, in the Skylight Room. Please tion Center, the meeting center and loca- ad hoc events, but those who might be register in advance for this luncheon. tion of all major meeting events, and interested should leave their local address Cost: $12. smaller blocks of rooms have been and telephone number at the Registration The Annual Banquet will be reserved at other nearby hotels. Meeting Desk in the lobby outside University Hall held in the Skylight Room on Thursday registrants and guests are responsi- at the Clarion Hotel and Convention evening, April 22, preceded by a social ble for making their own lodging Center. hour beginning at 6 p.m. Please register arrangements. Reservations should be in advance. Cost: $22. made no later than March 20, 1999, MEALS A Special Address will follow the to guarantee the special room rates that Annual Banquet at 8 p.m. in the Wiscon- There are numerous restaurants have been negotiated for this meeting. sin Room on the main floor and accessible within easy walking distance of the Be sure to indicate that you are participat- to those who do not attend the banquet. Clarion Hotel and Convention Center. ing in the North-Central Section of the There is no charge for attendance at this A selected list of restaurants with addi- Geological Society of America meeting event. tional information on price ranges, avail- to receive the special room rate. Meeting Breakfast meetings are scheduled for able ethnic cuisines, and addresses will be registrants are encouraged to take advan- 7 a.m., Friday, April 23, for GSA North- included in the registration materials tage of the more economical and conve- Central Section Campus Representa- available at the meeting. nient facilities at the Clarion Hotel and tives in the Patio East Room (no charge) Convention Center by registering to stay and the Association for Women Geo- at the meeting center. scientists in the Patio West Room

28 GSA TODAY, February 1999 1. Clarion Hotel and Convention Center. 1501 South Neil St., Champaign, Active Strike-Slip and Collisional Tectonics of the IL 62820, (217) 352-7891; $49 Single, $60 llee Northern Caribbean Plate Boundary Zone Double, $80 Triple. aabb edited by J. F. Dolan, 2. Radisson Suite Hotel. 101 Trade iill P. Mann, 1998 Centre Dr., Champaign, IL 62820, RECENT RELEASESvaa AAv This volume presents an integrated set (217) 398-3400; $62 Single, $72 Double. ww 3. Quality Hotel—University Center. oo of four chapters on the geological, 302 E. John St., Champaign, IL 62820, NN geophysical, and seismological nature of (217) 383-2277; $56 Single, $64 Double. a 1,000-km-long segment of the active 4. Hampton Inn at U of I. 1200 W. Caribbean-North America plate boundary between University Ave., Urbana, IL 61801, Puerto Rico and southern Cuba. The complex plate (217) 337-1100; $59 Single, $65 Double. boundary zone revealed by these combined onland GETTING TO CHAMPAIGN and offshore data encompasses an along-strike The Clarion Hotel and Convention transition from oblique subduction to strike-slip Center is located in Champaign adjacent deformation; a zone of active collisional under- to the campus of the University of Illinois. thrusting of high-standing Bahamas carbonate banks; Champaign is reached by major highways a major restraining bend similar in character to the including I-74, I-72, I-57, U.S. Hwy. 150, Big Bend region of the San Andreas fault system in and U.S. Hwy. 45. Champaign is served by several airlines via the University of Illi- California; and opposing subducted slabs that collide nois Willard Airport, is a hub for Grey- in the upper mantle beneath western Puerto Rico. hound Bus, and is served by Amtrak from This is the first comprehensive description of the Chicago or New Orleans. Septentrional fault — the major plate-boundary, sinistral strike-slip fault — and the offshore zone of PARKING predominantly contractional deformation formed Parking at the Clarion Hotel and between the obliquely colliding Bahamas banks and Convention Center is abundant and free the island of Hispaniola. The authors also discuss to registrants who are also staying in the hotel. earthquakes, while placing constraints on the mechanics and geometry of the deep plate EXHIBITS boundary, as well as on the orientation of relative Exhibits of educational and commer- plate motions. This combined data set delineates cial organizations will be on display in the the relations between plate motions, the active Alumni Room of the Clarion Hotel and faults that accommodate these motions, the Convention Center close to the symposia, earthquakes generated by these faults, and the technical sessions, and displays and in the same room as the poster sessions. Exhibit seismic hazards that the earthquakes pose to this space must be reserved by March 19, 1999. densely populated and rapidly developing region. For further information, contact Jen- SPE326, 186 p., indexed, ISBN 0-8137-2326-4, $60.00, Member price $48.00 nifer K. Hines, (217) 244-2410, fax 217- 244-0802, [email protected], Illinois Late Cenozoic Xianshuihe-Xiaojiang, Red River, and Dali Fault Systems of State Geological Survey, 615 East Peabody Southwestern Sichuan and Central Yunnan, China Dr., Champaign, IL 61820. by E. Wang, B. C. Burchfiel, L. H. Royden, Chen Liangzhong, ADDITIONAL INFORMATION Chen Jishen, Li Wenxin, 1998 The Tibetan plateau and its surrounding mountain ranges and basins are a natural Visit our Web site at http://www.isgs. uiuc.edu/isgsroot/gsa-site/gsahome.html laboratory in which to study geological processes ranging from continental collision for the latest information. Inquiries, tectonics to effects of plateau development on climate. Three active fault systems, the requests, or suggestions should be directed Xianshuihe-Xiojiang, Red River, and Dali, offer clues about the extrusion of crustal to General Chair Dennis R. Kolata, (217) fragments eastward from the Tibetan plateau, how far back into time the present pattern of 244-2189, fax 217-333-2830, kolata@ deformation can be projected, and the relation between these fault systems and the isgs.uiuc.edu, GSA North-Central Section, Illinois State Geological Survey, 615 East intracontinental deformation of the India-Eurasia collision zone. The region of these fault Peabody Dr., Champaign, IL 61820. ■ systems is an example of rapid changes in partitioning of strain during 5 m.y. in a rotational tectonic regime. SPE327, 112 p., ISBN 0-8137-2327-2, $41.00, Member price $32.80

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GSA TODAY, February 1999 29 Penrose Ophiolites and Oceanic Crust: New Insights from CONFERENCE Field Studies and Ocean Drilling Program REPORT

Conveners pollination of ideas from investigators in Yildirim Dilek, Department of Geology, Miami University, Oxford, OH 45056, both oceanic and continental terranes and [email protected] diverse approaches of field geology, geo- Eldridge M. Moores, Department of Geology, University of California, Davis, CA 95616, chemistry, and geophysics. [email protected] In the first session, Ken Macdonald Don Elthon, National Science Foundation, Arlington, VA 22230, [email protected] presented the evidence and significance of Adolphe Nicolas, Université Montpellier II—CNRS, 34095 Montpellier, France, off-axis volcanic activity for melt distribu- [email protected] tion beneath mid-ocean ridges and for the evolution of oceanic crust. He noted that the highly asymmetric zone of primary Ophiolites have been of particular on ophiolites, during which the definition melting at the East Pacific Rise near 17°S, importance in the reconstruction of of an ophiolite was developed. as deduced from the MELT (Mantle Elec- ancient plate boundaries ever since their The conference, “Ophiolites and tromagnetic and Tomography) experi- recognition as on-land fragments of Oceanic Crust: New Insights from Field ment, mimics the asymmetric distribution oceanic lithosphere. The internal architec- Studies and Ocean Drilling Program” was of seamount chains and the asymmetry ture of well-preserved ophiolite complexes convened in Marshall, California, Septem- in seafloor subsidence in the area. He con- shows that ophiolites are good structural ber 13–17, 1998. It brought together 86 cluded that processes occurring as deep as analogues for oceanic crust, providing earth scientists, with backgrounds ranging 200 km beneath the oceanic crust may three-dimensional exposures and age rela- from structural geology, tectonics, and have an imprint on the seafloor that can tions to study the nature of extensional geophysics to petrology and geochemistry. be mapped. Jeff Karson emphasized the tectonics and magmatic construction in Participants, of whom 12 were students, complexity and the heterogeneity of the oceanic spreading environments. Thus, came from 12 countries. internal structure of both modern oceanic ophiolites complement significantly our crust and ophiolite. This complex struc- knowledge of the architecture and genera- PRESENTATIONS AND PANEL ture is an artifact of highly asymmetric tion of oceanic crust that is derived DISCUSSIONS magmatic and tectonic processes operat- mainly from seismic images and drill holes ing at mid-ocean ridges which create The conference was organized into at mid-ocean ridges. However, the geody- “tectonic windows,” major faulted escarp- five major sessions: 1—Structural and namic setting of many ophiolites remains ments on the seafloor, where crustal and magmatic processes at oceanic spreading controversial, as a result of petrological mantle structures can be investigated in centers; 2—Ophiolite–ocean crust analogy and geochemical observations that imply three dimensions. Henry Dick presented and field observations; 3—Petrology and magmatic affinities to subduction zone a comparison of structural and magmatic geochemistry of oceanic crust and ophio- settings, rather than mid-ocean ridge envi- processes at spreading centers, as seen lites; 4—Hydrothermal alteration and ronments. Recent multidisciplinary stud- from in situ lower oceanic crust and shal- mineralization of oceanic crust and ophio- ies of intact ophiolites and drilled core low mantle. He discussed the occurrence lites; 5—Active margin tectonics, orogeny, samples of modern oceanic crust from var- of large variations in the stratigraphy of and emplacement mechanisms of ophio- ious mid-ocean ridge and subduction zone the ocean crust at slow-spreading ridges, lites. The invited talks introduced an settings have provided significant infor- reflecting along-axis transport of melt in overview of current ideas, observations, mation on the mantle heterogeneity, the lower crust from a central intrusive and interpretations on various themes magma chamber processes, melt migra- center, and the significance of synmag- and case studies related to these topics. tion, and geochemical evolution of matic deformation in melt transport and In addition, the two evening sessions magma in these modern tectonic settings igneous differentiation. These observa- on Ophiolites and the Sedimentary Record and in ancient spreading environments, tions indicate that the evolution of slow- (Robert Coleman and Emile Pessagno, Jr.) thus leading toward a better understand- spreading oceanic crust deviates signifi- and Current Thoughts on the California ing of oceanic crust formation and toward cantly from the Penrose ophiolite Coast Ranges (John Shervais, Ray Inger- resolving the structural-geochemical paradigm. Peter Kelemen addressed the soll, and Clifford Hopson) highlighted conundrum. Within this context, we orga- topics of magmatic processes and melt some of the unresolved questions and out- nized a Geological Society of America Pen- transport in the mantle and the nature of standing controversies on the geological rose Conference to bring together a multi- crust-mantle transition. He discussed the evolution of the Jurassic ophiolites and disciplinary group of geoscientists from probability of porous flow processes con- the Mesozoic active margin tectonics of the communities of ophiolite geology and trolling the first-order geometry of melt- the western United States, and provided a marine geology and geophysics to reevalu- transport networks beneath ridges and stimulus for the field trip to the California ate the existing models on oceanic crust producing trace element enrichments. Coast Ranges on the third day of the generation, ophiolite formation, and ophi- In the second session, Eldridge meeting. Another informal evening ses- olite-ocean crust analogy; to explore the Moores discussed the significance of the sion gave us an opportunity to learn about possibility of reaching a new consensus scale and distribution of mantle hetero- the geology of oceanic crust exposed on on the architecture of oceanic lithosphere; geneity for the generation of ophiolitic Macquarie Island (Australia) through Rick and to discuss the significance of ophio- magmas. The composition of magmas Varne’s (University of Tasmania) slide pre- lites and oceanic crust for the present plate at spreading centers may depend upon sentation. A daily panel discussion facili- tectonic processes and for processes in the a complex tectonic history lasting for tated exchange among the diverse partici- geological past. The timing of this meeting millions of years. Moores stated that geo- pants. This format was most effective in nearly coincided with the 25th anniver- chemical indicators must be used inte- providing a forum that promoted active sary of the first Penrose Field Conference grally in concert with geological informa- participation of all attendees and cross-

30 GSA TODAY, February 1999 tion to obtain the most robust tectonic Penrose Conference Participants interpretation of a given ophiolite. Tjerk Peters presented the geology of the Jeffrey Alt Patricia Fryer Tenuaki Ishii Julian Pearce Piera Spadea Neil Banerjee Harald Furnes Barbara John Emile Pessagno, Jr. Debra Stakes Masirah ophiolite on the southeast Ara- Jean Bédard Jennifer Georgen Jeffrey Karson Tjerk Peters Marnie Sturm bian continental margin and discussed its Donna Blackman A. Mohamad Ghazi Peter Kelemen Philippe Pezard Guenter Suhr evolution at a ridge-transform intersection Françoise Boudier Kathryn Gillis Deborah Kelley Stephen Phipps Damon Teagle in the proto–Indian Ocean. The unusually Roger Buck Nicola Godfrey Martin Kleinrock Victor Ramos Craig Thomas John Chen David Goldberg Astri Jaeger Kvassnes Elisabetta Rampone Ricardo Tribuzio thin (~500 m) plutonic sequence in the James Cochran Robert Gregory Jian Lin Paul Robinson Brian Tucholke Masirah ophiolite might have been related Robert Coleman Bradley Hacker Ken Macdonald Sarah Roeske Rick Varne to a weak magma supply as a result of the Henry Dick Gregory Harper Bruce Malfait Daniel Kent Ross Scott Veirs “cold-edge effect” of the bounding conti- Arjan Dijkstra Ron Harris Craig Manning Jane Scarrow John Wakabayashi Grenville Draper Rachel Haymon Rodney Metcalf Hans Schouten Timothy Wallin nental blocks, rather than tectonic thin- Stephen Edwards Ben Holtzman Jay Miller Anjana Shah Scott White ning. Jean Bédard described syntectic Andrew Fisher Clifford Hopson Thomas Moore John Shervais Aaron Yoshinobu assimilation processes and magmatic Martin Fisk Susan Humphris Pierre Nehlig Alan Smith Rovert Zierenberg differentiation patterns in the plutonic Gretchen Steve Hurst Julie Newman Jonathan Snow Frueh-Green Ray Ingersoll Yujiro Ogawa Rachel Sours-Page sequence of the Bay of Islands (Newfound- land) ophiolite and discussed their signifi- cance in development of melt evolution ophiolites. He concluded that the cored tion zone, and the heat source of a and crustal heterogeneity at all scales. This section from the Southwest Indian Ridge seafloor large massive sulfide deposit. Her discussion suggests that the assumption is unlike typical “Penrose-type ophiolites” calculations suggest that there is an insuf- of fractional crystallization being the only and that ophiolites representing an ultra- ficient amount of new material intruded process controlling melt evolution may slow-spreading ridge environment might at the ridge axis each year at steady state generate incorrect calculations of parental not have been preserved in the rock to provide the heat necessary to drive a melts, leading to erroneous conclusions record. large hydrothermal system (1000 MW), about mantle sources and processes. Hans In the fourth session, Jeff Alt dis- and therefore heat must be extracted Schouten compared the structure of the cussed the mechanism and effects of either from individual magma bodies or volcanic stratigraphy drilled in Ocean hydrothermal alteration in seafloor from heat stored at depth in the crust. She Drilling Program (ODP) Hole 504B at the spreading environments as recorded in then utilized this discussion to constrain Costa Rica Rift and in Hole CY-1/1A in the young oceanic crust and ophiolites. He the growth of large ophiolite-based mas- Troodos ophiolite, Cyprus, and suggested reviewed the main differences between sive sulfide deposits. that the contrasting kinematic histories hydrothermal effects in oceanic and ophi- In the final session, Nicola Godfrey and deformation in the lavas and sheeted olitic crust. Many ophiolites have a higher presented generalized crustal-scale cross dikes in 504B and near CY-1/1A may grade of metamorphism of volcanic rocks sections of the Great Valley in California reflect their contrasting mechanical and more continuous geothermal and at different latitudes which are based on response to lava burial, rather than metamorphic gradients than are seen in seismic-reflection, bore hole, gravity, and faulting. oceanic crust. The primary volatile con- aeromagnetic data, and discussed the Julian Pearce began the third session tents of the rocks, the abundances of 600-km-long, 70-km-wide ophiolitic slab by summarizing new and published meth- mafic phases and glassy groundmass, beneath the Great Valley forearc basin. ods, each of which yields a geochemical styles of faulting and fracturing, and mul- The existence of such an extensive ophi- fingerprint that can be related to present tiple phases of intrusion and eruption may olitic slab beneath the Great Valley basin tectonic settings empirically and/or using contribute to these differences. Rachel has strong implications for the tectonics of petrogenetic reasoning. He discussed sev- Haymon discussed the importance of shal- the coeval ophiolites in the Sierra Nevada eral modern analogues for oceanic crust low crustal magma supply and delivery foothills on the east and the Coast Ranges formation in suprasubduction-zone envi- configuration to ridge-crest hydrothermal on the west, and for the Mesozoic active- ronments and the processes affecting arc systems, on the basis of observations from margin tectonics of the western United magma composition in these settings. Elis- the East Pacific Rise and the Semail ophio- States. Bradley Hacker reviewed the recent abetta Rampone presented an overview of lite. She concluded that the distribution data on the thermochronology and ther- the petrogenesis of the Ligurian ophiolites and geochemical character of hydrother- mobarometry of the metamorphic sole in the Apennines of Italy and discussed mal alteration on ridge crests are funda- of the Semail ophiolite which imply the occurrence of the Jurassic MORB-type mentally different in magma-rich, dike- extremely rapid subduction (~200 km/m.y.) oceanic crust in the Internal Liguride belt dominated segments (fast-spreading), beneath a very young oceanic crust. The and variably old subcontinental litho- compared to magma-starved, fault-domi- key questions still remaining are the mag- spheric mantle in the External Liguride nated segments (slow-spreading). Debbie nitude, style, and age of extension of the belt. The data thus suggest that the Lig- Kelley discussed the geochemical, isotopic, Semail ophiolite, and the timing of high- urian ophiolites do not represent the rem- and thermal history of fluids circulating in pressure metamorphic events. Adolphe nants of mature oceanic lithosphere, but the oceanic crust from magmatic to Nicolas presented a comparative study rather an early stage of ocean crust forma- hydrothermal vent conditions and the of the inferred microplate tectonics of tion in the Ligurian Tethys. Stephen role of these fluids in crustal development the Semail ophiolite, the Easter Island Edwards addressed melt migration and and microbial processes. Her discussion microplate, and the Magellan Plateau, and reaction in conductive mantle lithosphere suggests that lower oceanic crust is a discussed the kinematics of rapid rotation with a specific reference to the Bay of potentially major reservoir for abiogenic at spreading centers and rotation-related Islands ophiolite and discussed the poten- methane in submarine hydrothermal sys- compressional deformation at the tip of tial of these processes to cause significant tems, and that carbon-bearing fluids in propagating ridges. Ophiolites that display chemical modification of melt and mantle gabbros may provide a critical energy evidence for large rotations (i.e., Troodos, at shallow depth. Paul Robinson reviewed source for diverse microbial populations in Semail) soon after their igneous accretion the structure, stratigraphy, and petrology the sub-seafloor. Susan Humphris pre- might have originated as a result of of lower oceanic crust, formed at the sented thermal and geochemical mass bal- microplate tectonics. Alan Smith reviewed Southwest Indian Ridge, that has been ances for the TAG active hydrothermal the current models on ophiolite emplace- drilled in ODP Hole 735 B, and compared mound and discussed their implications its characteristics to those of well-known for the time of formation, the size of reac- Ophiolites continued on p. 32

GSA TODAY, February 1999 31 Ophiolites continued from p. 31 participated in the first Penrose field con- SUMMARY ference on ophiolites in 1972; they also Participants collectively agreed that ment mechanisms and discussed the gave a short account of the progress made more integrated and interdisciplinary involvement of two distinct subduction in ophiolite and ocean crust studies since studies of modern oceanic crust and ophi- phases during the terminal obliteration of then. These discussions and the state- olites are needed to foster collaboration ocean floor. The origin of the forces that ments by other participants confirmed between the members of the marine geol- lead to the relative velocities appropriate that the original Penrose definition of ogy and geophysics community and ophi- for ophiolite emplacement is likely large- ophiolite has been very useful and remains olite geologists in order to address the scale changes in the geometry and relative effective in ophiolite–ocean crust compar- questions that arose during the panel dis- velocities at plate margins. isons, as long as the term is used indepen- cussions. Systematic and detailed struc- The poster sessions provided an dently of its origin and/or tectonic signifi- tural, kinematic, petrological, and geo- opportunity for participants to present cance. The Penrose definition needs to be physical process-oriented studies both in case studies and their results on different expanded, however, to include more infor- ophiolites and modern oceanic crust are aspects of the topics of the five major ses- mation about the geological context of important for modeling oceanic systems. sions, and an effective way of initiating individual complexes as revealed in the Of particular significance for future studies and stimulating discussions. The content underlying and overlying rock units. are establishing objective criteria for struc- varied from the geophysics of oceanic core tural reference frames (paleohorizontal complexes, thermal effect of a melt lens at FIELD EXCURSION and younging direction) in oceanic rocks, Moho, estimations of strain rates in the The third day of the conference was finding ways to constrain pressure-temper- uppermost mantle, and processes of shear- devoted to field examination of the ature-time paths for oceanic mafic and zone development in oceanic lithosphere, Coast Range ophiolite and ophiolitic rocks ultramafic rocks, and better defining the to the nature of magma—hydrothermal within the Franciscan Complex. The Coast geological significance of the geophysical transition in ophiolites and oceanic crust, Range ophiolite is a good example of the models for oceanic crust structure. textural and chemical evidence for micro- “ophiolite conundrum,” as abundantly Scientific drilling in the oceans bial alteration of the upper oceanic crust, demonstrated by the presentations of has been instrumental in advancing our PGE and Os isotope systematics of the Shervais, Ingersoll, and Hopson during knowledge of the oceanic lithosphere. The oceanic mantle, isotope evidence for the conference. Proposed emplacement priorities of future deep-earth sampling in recent contamination of the mantle mechanisms (as well as the general the marine environment include drilling beneath the Southern Chile Ridge, evi- regional geological setting) for the Coast an intact section of modern oceanic crust, dence for delivery of unpooled fractional Range ophiolite differ from those of typi- preferably 3 km into the basement, drilling melts to the oceanic crust as recorded in cal “Tethyan-type” ophiolites. The Coast the plutonic foundation of oceanic crust, gabbros, and significance of serpentine Range ophiolite structurally overlies the and drilling into the complete crust and and blueschist mud volcanism in conver- Franciscan subduction complex, rather crust-mantle boundary (goals of the gent margins. than the continental margin. The Great “Mohole” project), and finally a compre- The first panel discussion addressed Valley ophiolite, on the other hand, hensive program aimed at a fuller under- some overarching questions, such as how appears to overlie the continental margin standing of the structural and composi- melt is focused beneath spreading seg- (Godfrey). The structural complexity of tional variations in modern and ancient ments and how it is diffused into the the ophiolitic–subduction complex con- oceanic crust in relation to ophiolites. crust; how melt is translated into lower tact, as well as the present-day geometry crustal structure; the mode and nature of the contact, is a product of a series of ACKNOWLEDGMENTS of brittle and ductile behavior of lower complex tectonic interactions, including crust and upper mantle and associated We thank the Geological Society of its major reactivation during the late hydrothermalism; causes and conse- America for sponsoring the conference Cenozoic transform regime. quences of episodicity; diagnostic features and providing funds to enable student Following an introductory presenta- to distinguish the tectonic setting of ophi- participation, and the Joint Oceano- tion on the regional and local geology olites and to determine the spreading rate graphic Institutions/USSAC and the of the California Coast Ranges by Moores and magma budget in paleo–spreading Marine Geology and Geophysics Program and John Wakabayashi, participants had environments; and differentiating spread- of the National Science Foundation for an opportunity to examine one of the rare ing-related structures from emplacement- provision of grants to support travel by occurrences of a sheeted dike complex in related structures in ophiolites. The sec- participants and for field trip preparation. the Coast Range ophiolite in Mt. Diablo, ond panel discussion focused on melt We thank Lois Elms (Western Experience, as well as a depositional contact of the transport mechanisms in the mantle and Inc.) and the staff of the Marconi Confer- basal Great Valley Group sedimentary crust; constraints on the age of ophiolite ence Center (California State Parks) for rocks on volcanic rocks of the Coast generation and emplacement; what con- effective and efficient logistics throughout Range ophiolite in the Oakland Hills. At trols serpentinization and the depth of the meeting. John Wakabayashi kindly Tiburon, participants observed the mantle seawater penetration into the upper man- helped us organize and run an informative base of the Coast Range ophiolite in tle; what the reaction zone is and how a and stimulating field trip in the California which serpentinized peridotites are pre- sufficient volume of fluid moves through Coast Ranges. We thank RMC Lonestar sent at the structurally highest horizon in it; what makes large ore deposits in Company for help in arranging a stop on the Franciscan subduction complex. oceanic crust and ophiolites; how mantle the field trip at the Clayton Quarry in Mt. Blocks of eclogite, amphibolite, and temperatures, viscosity, and flow in supra- Diablo to examine a well-exposed sheeted blueschist occur as tectonic inclusions in subduction zone settings differ from those dike complex. We are grateful for the sup- the serpentinite. At the Nicasio Reservoir, at mid-ocean ridges; what we know about port and input provided to us by the par- a >1-km-thick pillow basalt section and the architecture of suprasubduction zone ticipants before, during, and after the con- an underlying gabbro possibly represent settings; and how distinct the composi- ference. We thank them all for the synergy part of a seamount that was incorporated tions of suprasubduction zone magmas are and excitement they brought to the meet- into the Franciscan complex in late Meso- from those of mid-ocean ridges. The final ing and for sharing their knowledge and zoic–early Cenozoic time. panel discussion started with a short remi- observations with the community. ■ niscence by each panel member, who had

32 GSA TODAY, February 1999 1999 Annual Meeting and Exposition

Denver, Colorado October 25–28 Colorado Convention Center

GENERAL CO-CHAIRS Mary J. Kraus and David Budd University of Colorado, Boulder

TECHNICAL PROGRAM CHAIRS Craig Jones and G. Lang Farmer University of Colorado, Boulder Proposal Deadline was January 6.

FOR FIELD TRIP INFORMATION Call Edna Collis at GSA (303) 447-2020, Crossing Divides ext. 134, [email protected]. No more field trips will be accepted.

FUTURE GSA MEETINGS FOR INFORMATION ON ANY GSA MEETING CALL THE 2000 Reno, Nevada, November 13–16 GSA MEETINGS DEPARTMENT 2001 Boston, Massachusetts, November 5–8 1-800-472-1988 or • (303) 447-2020, ext. 113 2002 Denver, Colorado, October 28–31 fax 303-447-0648 • [email protected] 2003 Seattle, Washington, November 2–5 Or see GSA’s Web page at http://www.geosociety.org

1999 GSA SECTION MEETINGS

SOUTH-CENTRAL SECTION — March 15–16, 1999, Lubbock, ROCKY MOUNTAIN SECTION — April 8–10, 1999, Pocatello, Texas. Information: Calvin Barnes, Dept. of Geosciences, Texas Idaho. Information: Scott S. Hughes, Dept. of Geology, Idaho Tech, Lubbock, TX 79409-1053, (806) 742-3106, [email protected]. State University, 785 South 8th Ave, Pocatello, ID 83209-8072, Preregistration deadline: February 5, 1999. (208) 236-4387, [email protected]. Preregistration deadline: March 5, 1999. NORTHEASTERN SECTION — March 22–24, 1999, Providence, Rhode Island. Information: O. Don Hermes, Dept. of Geology, NORTH-CENTRAL SECTION — April 22–23, 1999, Champaign- University of Rhode Island, Green Hall, Kingston, RI 02881, Urbana, Illinois. Information: Dennis R. Kolata, (217) 244-2189, (401) 874-2192, [email protected]. Preregistration deadline: fax 217-333-2830, [email protected]. Preregistration deadline: February 12, 1999. March 19, 1999. SOUTHEASTERN SECTION — March 25–26, 1999, Athens, CORDILLERAN SECTION — June 2–4, 1999, Berkeley, California. Georgia. Information: Samuel E. Swanson, Dept. of Geology, Submit completed abstracts to: George Brimhall, Dept. of Geology University of Georgia, Athens, GA 30602-2501, (706) 542-2415, & Geophysics, University of California, Berkeley, CA 94720-4767, [email protected]. Preregistration deadline: February 19, (510) 642-5868, [email protected]. Abstract 1999. deadline: February 19, 1999.

GSA TODAY, February 1999 33 February BULLETIN and GEOLOGY Contents

The Geological Society of America 240Ð253 Geochronology and geochemistry of Putnam-Nashoba terrane metavolcanic and plutonic rocks, eastern Massachusetts: Constraints on the early Paleozoic evolution of eastern North America Volume 111, Number 2, February 1999 Martin Acaster and M. E. Bickford 254Ð263 The dimensions and topographic setting of Antarctic subglacial lakes 159Ð176 Origin of the upper Capitan-Massive limestone (Permian), Guadalupe and implications for large-scale water storage beneath continental Mountains, New MexicoÐTexas: Is it a reef? ice sheets J. A. Fagerstrom and O. Weidlich Julian A. Dowdeswell and Martin J. Siegert 177Ð188 Ground-water, large-lake interactions in Saginaw Bay, Lake Huron: 264Ð274 Paleoclimatology and provenance of the glaciogenic Gowganda A geochemical and isotopic approach Formation (Paleoproterozoic), Ontario, Canada: A chemo- Jonathan J. Kolak, David T. Long, Jane M. Matty, Graham J. Larson, stratigraphic approach Duncan F. Sibley, and Terry B. Councell Grant M. Young and H. Wayne Nesbitt 189Ð203 Depositional setting and implications of Paleoproterozoic glacio- 275Ð290 Paleofluid-flow circulation within a Triassic rift basin: marine sedimentation in the Hamersley province, Western Australia Evidence from oil inclusions and thermal histories David McB. Martin Hsin-Yi Tseng, R. C. Burruss, T. C. Onstott, and Gomaa Omar 204Ð218 Late Holocene stratigraphy of the Tetimpa archaeological sites, 291Ð303 Ontogeny of a flood plain northeast flank of Popocatépetl volcano, central Mexico John A. Moody, James E. Pizzuto, and Robert H. Meade Maria S. Panfil, Thomas W. Gardner, and Kenneth G. Hirth 304Ð315 Importance of mechanical disaggregation in chemical weathering in 219Ð239 Fringe cracks: Key structures for the interpretation of the progressive a cold alpine environment, San Juan Mountains, Colorado Alleghanian deformation of the Appalachian Plateau Anthony R. Hoch, Michael M. Reddy, and James I. Drever Amgad I. Younes and Terry Engelder

VOLUME 27 NO. 2 P. 97Ð192 FEBRUARY 1999

99 Stratigraphic classification of ancient lakes: Balancing tectonic and 151 Back folds in the core of the Himalayan orogen: An alternative climatic controls interpretation Alan R. Carroll, Kevin M. Bohacs Laurent Godin, Richard L. Brown, Simon Hanmer, Randall Parrish

103 Mariana blueschist mud volcanism: Implications for conditions within 155 Carbon-isotope composition of Lower Cretaceous fossil wood: the subduction zone Ocean-atmosphere chemistry and relation to sea-level change P. Fryer, C. G. Wheat, M. J. Mottl Darren R. Gröcke, Stephen P. Hesselbo, Hugh C. Jenkyns

107 Widespread bacterial populations at glacier beds and their 159 Relating eolian bounding-surface geometries to the bed forms that relationship to rock weathering and carbon cycling generated them: Etjo Formation, Cretaceous, Namibia Martin Sharp, John Parkes, Barry Cragg, Ian J. Fairchild, Helen Lamb, Martyn Tranter Nigel Mountney, John Howell, Stephen Flint, Dougal Jerram

111 Abnormal reverse faulting above a depleting resevoir 163 Tectonic and sediment supply control of deep rift lake turbidite Francis Odonne, Isabelle Ménard, Gérard J. Massonnat, Jean-Paul Rolando systems: Lake Baikal, Russia C. Hans Nelson, Evgeny B. Karabanov, Steven M. Colman, Carlota Escutia 115 Redox state of the Archean atmosphere: Evidence from detrital heavy minerals in ca. 3250–2750 Ma sandstones from the Pilbara Craton, 167 Early Jurassic hydrothermal vent community from the Franciscan Australia Complex, San Rafael Mountains, California Birger Rasmussen, Roger Buick Crispin T. S. Little, Richard J. Herrington, Rachel M. Haymon, Taniel Danelian

119 Time-dependence of the stress shadowing effect and its relation to 171 Effects of climate and landscape development on the terrestrial the structure of the lower crust phosphorus cycle Shelley Kenner, Paul Seagall Gabriel M. Filippelli, Catherine Souch

123 Timing of collision of the North and South China blocks: Controversy 175 Synorogenic hydrothermal origin for giant Hamersley iron oxide ore and reconciliation bodies Qing-Ren Meng, Guo-Wei Zhang Christopher McA. Powell, Nicholas H. S. Oliver, Zheng-Xiang Li, David McB. Martin, Janos Ronaszeki 127 Ephemeral crustal thickening at a triple junction: The Mendocino crustal conveyor 179 Radiocarbon constraints on ice sheet advance and retreat in the Kevin P. Furlong, Rob Govers Weddell Sea, Antarctica John B. Anderson, John T. Andrews 131 Black Giants Anorthosite, New Zealand: A Paleozoic analogue of Archean stratiform anorthosites and implications for the formation 183 Scaling of sedimentation rates and drowning of reefs and of Archean high-grade gneiss terranes carbonate platforms George M. Gibson, Trevor R. Ireland Wolfgang Schlager

135 Revised age of the Rockland tephra, northern California: Forum Implications for climate and stratigraphic reconstructions in the 187 Environmental change controls of lacustrine carbonate, Cayuga Lake, western United States New York Marvin A. Lanphere, Duane E. Champion, Michael A. Clynne, L. J. Patrick Muffler Comment: Jane L. Teranes, Judith A. McKenzie Reply: Henry T. Mullins 139 Magmatic crystallization, isobaric cooling, and decompression of the garnet-bearing assemblages of the Jijal sequence (Kohistan terrane, 189 Sea level–climate correlation during the past 1400 yr western Himalayas) Comment: Johan C. Varekamp, Ellen Thomas, W. G. Thompson Luci Ringuette, Jacques Martignole, Brian F. Windley Reply: Orson van de Plassche, Klaas van der Borg, Arie F. M. de Jong

143 Occurrence, age, and implications of the Yagan—Onch Hayrhan 191 Structural analysis of metasedimentary enclaves: Implications for metamorphic core complex, southern Mongolia tectonic evolution and granite petrogenesis in the southern Lachlan L. E. Webb, S. A. Graham, C. L. Johnson, G. Badarch, M. S. Hendrix Fold Belt, Australia Comment: David H. Taylor, Vince J. Morand, Ross A. Cayley 147 Rapid strand-plain accretion in the northeastern Nile Delta in the Reply: James A. C. Anderson, R. C. Price, Peter D. Fleming 9th century A.D. and the demise of the port of Pelusium Glenn A. Goodfriend, Daniel Jean Stanley

34 GSA TODAY, February 1999 For GSA Members and Friends CALL TODAY! HOLD A SPOT FOR YOURSELF AND FRIENDS

1999 GeoVentures Fee Schedule GeoTrip GeoHostel Geology of Hells Canyon Lewis & Clark Expedition Dates June 17–25 July 17–22 No. of Days 9 6 Member Fee $1400SOLD $750 OUT Nonmember Fee $1500 $800 Deposit $200 $100 Balance Due May 1 June 1 100% Deposit refund date before before (less processing fee) April 1 ($50) June 1 ($20)

We encourage you to make your decision as soon as possible. Air Travel: We urge you to make air travel arrangements Single or Shared Accommodation: Some trip fees are via Lethia K. Estigoy of Conventions in America (CIA). based on double occupancy. However, if you wish single accom- Her direct telephone number is (619) 232-4298, flycia@ modations, a limited number of rooms are available at extra scitravel.com. Lethia is ready to help you find the least ex- cost on a first-come, first-served basis. In the case of double pensive routing to your destination. Please call her for a no- occupancies, we will do our best to help find a suitable room- obligation price quote at the above number or at CIA’s toll-free mate, but if none is found, the single rate will apply. number 1-800-929-4242. The fax number is 619-232-6497. Age Requirement: Participants must be at least 21 years old. Cancellation Processing Fee: Deposits and payments are Health Recommendations and Special Needs: You must refundable, less processing fee, up to the cut-off date. Termina- be in good physical and mental health. Any physical condition tion by an individual during a trip in progress for any reason requiring special attention, diet, or treatment must be reported whatsoever will not result in a refund, and no refund will be in writing when the reservation is made. We will do our best to made for unused parts of the trip. accommodate special needs, including dietary requirements Full Itineraries: A detailed itinerary and helpful travel and physical disabilities. Please feel free to discuss your information are available from GSA. Please feel free to contact situation with us; however, we reserve the right to decline any Edna Collis, GSA Professional Development Department, at 1-800- person as a member of a trip. We also reserve the right to 472-1988, ext. 134, or (303) 447-2020, fax 303-447-0648, require a person to withdraw from the trip at any time when [email protected]. such action is determined to be in the best interests of the health, safety, and general welfare of the group. See p. 36 and 37 for trip descriptions.

DEPOSIT NO. OF TOTAL PAID REGISTER TODAY! PER PERSON PERSONS DEPOSIT GH991—Hells Canyon $200 ____ $______Send a deposit to hold your reservation; please pay by check or credit card. You will receive further information and a confirmation of your GH992—Dillon SOLD OUT $100 ____ $______registration within two weeks after your reservation is received. TOTAL DEPOSIT $______

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Phone (business/home) MAIL OR FAX REGISTRATION FORM AND CHECK OR CREDIT CARD INFORMATION TO: Guest Name 1999 GSA GeoVentures, GSA Professional Development Department GSA Member # P.O. Box 9140, Boulder, CO 80301 CALL TODAY FOR MORE INFORMATION: fax 303-447-0648 1-800-472-1988, x134, or (303) 447-2020, e-mail: [email protected], fax: 303-447-0648, check for updates: http://www.geosociety.org MAKE CHECKS PAYABLE TO: GSA 1999 GeoVentures

GSA TODAY, February 1999 35 GeoTrip uplift outpaces stream erosion. Landslide, slump, avalanche, allu- vial fan, terrace, Bonneville flood, and Mazama ash deposits chroni- From Pacific Islands to cle the late Quaternary and Holocene. Indian and European histo- ries complement the geology and add to the breadth of the trip. Snake River Rapids: This is an exceptional hiking and rafting trip for the physically fit person to see Hells Canyon and to learn about its geology. June is a The Geology beautiful time to visit the canyon, and the weather should be coop- erative. Bears, cougars, wild sheep, turkeys, eagles, deer, and elk of Hells Canyon, are among the animals that might be seen. Bring a bathing suit and fly rod if inclined to swim or fish.

Oregon and Idaho Schedule Thursday, June 17: Travel to Boise, Idaho. Board bus at 3:00 p.m. for three-hour ride to Halfway, Oregon. Stay at the Halfway Motel. Dinner at Canyon Outfitters. Your leader, Tracy Vallier, will present a slide lecture and video program after dinner. Friday, June 18: Breakfast at Canyon Outfitters. Roadside field trip along the southern 22 miles of Hells Canyon between Oxbow, Oregon, and the Hells Canyon Dam. Dinner at Canyon Outfitters. Return to Halfway Motel. Saturday, June 19: Breakfast at Canyon Outfitters. Bus ride to the launch site below Hells Canyon Dam. Raft Wild Sheep Rapids. Camp at Granite Creek. Sunday, June 20: Hike through the Wild Sheep Creek Forma- tion. Boat to Rush Creek landslide and hike to the top. Return to the rafts and float to Sheep Creek campsite. Monday, June 21: Hike to outcrops where the Permian- Triassic unconformity is exposed. Return to rafts and float to Suicide Point. Hike two miles through the Permian Cougar Creek dike complex to the Kirkwood Creek campsite. Tuesday, June 22: Boat to Upper Pittsburg Landing. Moderate Photo by Tracy Vallier. Photo by Tracy hike (one-half mile and 600 feet elevation gain) to observe the entire geologic framework of the Pittsburg Landing area. Hike one mile downhill to a petroglyph site on a Bonneville flood terrace. Board rafts at Lower Pittsburg Landing and float to Tryon Creek campsite. Wednesday, June 23: Moderate hike up Tryon Creek to Hells Canyon. observe outcrops of the Wild Sheep Creek Formation and possibly June 17–25, 1999 • 9 days, 8 nights to collect ammonite molds in fine-grained sedimentary rocks. Return to rafts and float through a Triassic gabbro, several miles Scientific Leader: Tracy Vallier, of the Miocene Columbia River Basalt Group (Imnaha Formation), Lewis-Clark State College, Lewiston, Idaho and Triassic plutons. Float to China Bar campsite. Field trip leader Tracy Vallier began his studies in Hells Thursday, June 24: Hike to mine tunnel where secondary cop- Canyon 35 years ago and recently completed a guidebook, Islands per minerals can be seen. Return to the rafts and float to Mountain and Rapids: A Geologic Story of Hells Canyon, published by Con- Chief Mine and Eureka Bar, where mining history and a unique fluence Press, Lewis-Clark State College, Lewiston, Idaho. Tracy Hells Canyon settlement will be discussed. Float to Cottonwood retired in 1997 from the U.S. Geological Survey, where he worked Creek, passing the mouths of the Imnaha and Salmon rivers. as a marine geologist with interests in island arcs and deep-sea Optional strenuous climb to the Triassic-Jurassic unconformity, processes. Before joining the USGS, Tracy taught at Indiana State where rocks of the Jurassic Coon Hollow Formation overlie the University and worked with the Deep Sea Drilling Project at Scripps Triassic Wild Sheep Creek Formation. Dinner awaits at the Cotton- Institution of Oceanography. He taught at Whitman College in wood Creek campsite. Walla Walla, Washington, during autumn 1998, and he is now an Friday, June 25: Float through the Jurassic Coon Hollow adjunct professor at Lewis-Clark State College in Lewiston, Idaho. Formation, a small Late Jurassic quartz diorite pluton, and then through the Wild Sheep Creek and Doyle Creek Formations and Description the Upper Triassic Martin Bridge Limestone. Arrive at the takeout One hundred miles of rugged outcrops are exposed in Hells point, Heller Bar, by noon for lunch, and then board the bus for the Canyon of the Snake River between Oxbow, Oregon, and the ride back to Boise, arriving at approximately 6:00 p.m. mouth of the Grande Ronde River in Washington. Arguably the deepest major river canyon in the lower 48 states, the Snake River Lodging, Meals, and Transportation flows more than 8,000 feet below the highest peak of the adjacent Canyon Outfitters, Inc. will provide all meals, field instruction, Seven Devils Mountains. Explore the viscera of an Early Permian professional river guides, river-related equipment (including through Middle Jurassic volcanic massif that formed along the camping gear), and transportation from Boise, Idaho beginning magmatic axis of the Blue Mountains island arc. See the dike zones at 3:00 p.m. on Thursday, June 17 through arrival back in Boise that crystallized beneath the volcanoes, visit volcano-root plutons, on Friday, June 25, at approximately 6:00 p.m. study the Permian, Triassic, and Jurassic strata that include a 500- Lethia K. Estigoy of Conventions in America (CIA) is familiar meter-thick Upper Triassic limestone, and put your hand on the with the trip itinerary and can handle all reservations in and out of Permian-Triassic unconformity. Review the evidence that the pre- Boise. Call Lethia direct at (619) 232-4298, [email protected]. Tertiary rocks are exotic to North America. Lava flows of the Miocene Columbia River Basalt Group that overlapped the exotic Physical Requirements terrane now perch on canyon rims and, in places, line the steep This trip includes several difficult, always optional, hikes that canyon walls near river level. The canyon is growing deeper as are usually less than two miles round trip from the boats. Although

36 GSA TODAY, February 1999 GeoHostel Description SOLD OUT From 1804 to 1806, Meriwether Lewis and William Clark jour- Geology of the Lewis neyed through the recently acquired Louisiana Territory on the order of President Thomas Jefferson. Arguably, the pivitol leg of the and Clark Expedition— expedition was in present-day Montana and Idaho, from the three forks of the Missouri River, over the Continental Divide, to the The Three Forks of the Missouri River of No Return. This trip is a geological and historical tour of that famous landscape. Our expedition will have two base camps, River to the River of No Return, Dillon, Montana, and Salmon, Idaho. The geological component of this GeoHostel will include field trips to see Archean metamorphic Montana and Idaho rocks, Proterozoic and Phanerozoic sedimentary rocks, Quaternary glacial deposits, hot springs and caverns, Sevier and Laramide com- pressional structures, and Tertiary extensional structures associ- ated with the northern edge of the Yellowstone hotspot track. The historical component will include stops at important landmarks from the Lewis and Clark Expedition such as the Three Forks, Beaverhead Rock, Clark’s Lookout, Camp Fortunate, and the Con- tinental Divide. The trip will also include a full-day raft trip on the Salmon River—the “River of No Return”—to see the spectacular geology of the river’s canyon.

Lodging, Meals, and Ground Transportation The group will stay on Saturday, Sunday, Monday, and Thurs- day nights at Western Montana College, Dillon, and on Tuesday and Wednesday nights at the Stagecoach Inn in Salmon, Idaho. All lodging is based on single occupancy or doubles for couples. Meals will include plenty of hors d’oeuvres at the Welcoming Reception and Orientation on Saturday evening, daily breakfasts and sack lunches, dinner on Sunday, and a hearty farewell dinner on Thursday evening. Field trip transportation will be provided in Along the Lewis and Clark Trail in southwest Montana. Photo by Rob Thomas. air-conditioned, 15-passenger vans.

Western Montana College of the University of Alternative Housing in Dillon, Montana Montana, Dillon, and Stagecoach Inn, Salmon, Idaho Costs of alternative (non–Western Montana College) housing July 17–22, 1999, (Saturday through Thursday) would be in addition to the GeoHostel fee. Reservations should be 5 days, 6 nights made directly by the registrant. Several motels are located in Dillon. GSA has reserved a small block of rooms at the following properties: Scientific Leaders: Rob Thomas and Sheila Roberts, Centennial Inn, A Victorian Bed & Breakfast. Advance reserva- Western Montana College, Dillon, Montana tions are strongly recommended. Call the Centennial Inn direct Rob Thomas is currently an associate professor and chair of at (406) 683-4454. Current double-room rate is $75.00 per night. the Department of Environmental Sciences at Western Montana Best Western Paradise Inn. Advance reservations are strongly College in Dillon. Rob developed an interest in the geology of the recommended. Call Best Western direct at (406) 683-4214. Cur- Lewis and Clark Expedition as a result of 13 years of research and rent double-room rate is $57.00 per night. teaching in southwestern Montana. His focus has been on the origin and timing of extensional tectonism in southwestern Montana, the Fee and Payment dynamics of carbonate platform development and destruction, $750 for GSA Members. $800 for Nonmembers. Cambrian mass extinctions, and field-based geoscience program A $100 deposit is due with your reservation and is refundable development. through June 1, less $20 processing fee. Total balance is due: Sheila Roberts is currently an associate professor of geology June 1. Maximum number of participants: 32. in the Department of Environmental Sciences at Western Montana Included: Classroom programs and materials; field trip trans- College in Dillon. Her focus has been on Pleistocene paleoclimates portation; lodging for six nights (single-occupancy, or double for recorded in saline lacustrine sediments. Sheila is also a strong couples); breakfast and lunch daily, dinner on Sunday, river raft advocate for service-learning in the geosciences, and has mentored trip, and welcoming and farewell events. her students on a number of community service projects along the Not included: Transportation to and from Dillon, Montana; Lewis and Clark trail in southwestern Montana. As a native Mon- transportation during hours outside field trips; and other expenses tanan, Sheila is an enthusiastic and knowledgable guide to the his- not specifically included. tory and geology of the Lewis and Clark Expedition. See p. 35 for registration form.

at a reasonable pace, with many points to rest and to explore the through April 1, 1999, less $50 processing fee. Total balance due geology, these hikes should be undertaken only by persons in good May 1, 1999. Minimum age: 21. health who are physically active. Verification of health coverage Included: All meals beginning with dinner on June 17 and will be required. No rafting experience is necessary. ending with lunch on June 25. Transportation by bus from Boise to Halfway and from Heller Bar back to Boise. All river equipment Fee and Payment including tents, dry bags, sleeping bags, sleeping pads, and geologi- GSA Member: $1,400 Nonmember: $1,500 cal reading materials, including, Island & Rapids—A Geologic Based on 17 people. The trip may cost more if there are fewer reg- Story of Hells Canyon, by your leader, Tracy Vallier. istrants. A $200 deposit, due with your reservation, is refundable Not included: Airfare to and from Boise, Idaho. See p. 35 for registration form.

GSA TODAY, February 1999 37 CLASSIFIED ADVERTISING

Published on the 1st of the month of issue. Ads (or can- Department of Physics and Geology, Northern Kentucky UNIVERSITY OF TORONTO AT SCARBOROUGH cellations) must reach the GSA Advertising office one University, Highland Heights, KY 41099-1900. Applica- PHYSICAL SCIENCES DIVISION month prior. Contact Advertising Department (303) tions will be accepted until Feb. 23, 1999. Additional infor- ENVIRONMENTAL SCIENCE 447-2020, 1-800-472-1988, fax 303-447-1133, or E-mail: mation about the university and department can be found Applications are invited for a tenure-track faculty position [email protected]. Please include complete at: http://www.nku.edu/~physics/. in Environmental Science at the University of Toronto at address, phone number, and E-mail address with all Northern Kentucky University's goal is to become a Scarborough, Division of Physical Sciences. The appoint- correspondence. pre-eminent learner-centered metropolitan university with ment, at the Assistant Professor level, would be effective a primary focus on the intellectual, ethical and career starting January 1, 2000. A completed Ph.D. is expected. Per line development of its students. By offering its students broad The successful candidate will have teaching and research Per Line for each access with the opportunity to succeed, the University interests in Soil Science, with ancillary teaching and for addt'l month actively contributes to the social, economic and cultural research interests in one or more of the following: Geo- Classification 1st month (same ad) vitality of the northern Kentucky/greater Cincinnati region morphology, Soil Chemistry, Soil or Sediment Contamina- Situations Wanted $1.75 $1.40 and the entire Commonwealth of Kentucky. In support of tion/Remediation; Soil Mineralogy. Positions Open $6.50 $5.50 these commitments, the University encourages and sup- Candidates should send their curriculum vitae, state- Consultants $6.50 $5.50 ports a culture of scholarly achievement, intellectual free- ments of teaching and specializations and research inter- Services & Supplies $6.50 $5.50 dom and creative problem solving. As part of a commit- ests, and arrange to have letters from three referees for- Opportunities for Students ment to its own multicultural community, the University warded before June 1, 1999 to: Professor James first 25 lines $0.00 $2.35 aggressively seeks to enhance our aspirations and hire Thompson, Chair, Division of Physical Sciences, Uni- additional lines $1.35 $2.35 those who will take pleasure and pride in making its priori- versity of Toronto at Scarborough, Scarborough, ON., Code number: $2.75 extra ties an integral part of their professional lives. NKU is an M1C 1A4, phone: (416) 287-7197; fax 416-287-7204; AA/EOE. Women and minorities are strongly encouraged e-mail: jthompso@ scar.utoronto.ca Agencies and organizations may submit purchase order or to apply. In accordance with Immigration Canada requirements, payment with copy. Individuals must send prepayment this advertisement is directed towards Canadian Citizens with copy. To estimate cost, count 54 characters per line, CALIFORNIA INSTITUTE OF TECHNOLOGY and Permanent residents of Canada. In accordance with including all punctuation and blank spaces. Actual cost ASSISTANT PROFESSOR OF PLANETARY SCIENCE its Employment Equity Policy, the University of Toronto may differ if you use capitals, centered copy, or special The Division of Geological and Planetary Sciences of the encourages applications from qualified women and men, characters. California Institute of Technology is seeking a planetary members of visible minorities, aboriginal peoples and per- scientist for a tenure-track faculty position as assistant sons with disabilities. To answer coded ads, use this address: Code #, professor; however, exceptionally well qualified applicants GSA Advertising Dept., P.O. Box 9140, Boulder, CO may also be considered at the associate or full professor FACULTY APPOINTMENT — TENURE-TRACK 80301-9140. All coded mail will be forwarded within level. Initial appointment is for four years and completion GEOLOGY/ENVIRONMENTAL SCIENCE 24 hours of arrival at GSA Today office. of the Ph.D. is required. We are seeking highly qualified Bellevue Community College (BCC), a two-year college in candidates who are committed to a career in research and the beautiful and thriving Puget Sound region of Washing- teaching. Any outstanding individual with a commitment to ton state, invites applications for a teaching position in increasing our knowledge of the solar system is welcome Geology/Environmental Science to begin Fall Quarter to apply. 1999. BCC is the third largest of the state's 48 public and Situations Wanted We are especially interested in individuals whose private post-secondary institutions. The college enrolls research links existing or new techniques with current pro- approximately 18,000 students (9,000 FTEs) in nearly 70 GEOSCIENTIST, Asset Builder/Manager, proven oil & gas grams in the Division. Three examples are listed below: program areas. BCC is diverse, innovative, and renowned record, US and Abroad, On-shore and Off-Shore. (1) Remote observations of planets, including Earth, for quality instruction. A Masters Degree in geology or Respond (318) 981-4678. from space. We are interested in candidates who have closely related earth science field is required. For more experience and/or interest in designing instruments and information and application forms, please call our 24-hour analyzing data from spacecraft and who will aggressively Jobline at (425) 643-2082, or check our Homepage at Positions Open seek involvement in planetary missions. Caltech's connec- www.bcc.ctc.edu/joblist, or leave a TDD/TTY message at tion with JPL is a valuable resource. (425) 603-4184. Bellevue Community College is an Equal (2) Observational planetary astronomy aimed princi- Opportunity Employer and operates under an Affirmative HASLEM POSTDOCTORAL FELLOWSHIP pally at outer solar system bodies, protoplanetary disks Action Plan, in accordance with applicable federal and A postdoctoral research position in Paleontology is avail- around young stars, and searches for other planetary sys- state laws and regulations. The college strongly encour- able in the Department of Geology and Geological Engi- tems. Here Caltech's telescopes and association with JPL ages all qualified applicants to apply. neering and Museum of Geology at the South Dakota offer unmatched opportunities. School of Mines and Technology. A Ph.D. with specializa- (3) Exploration of Mars and preparation for sample LAKE TAHOE COMMUNITY COLLEGE tion in Paleontology is required and preference will be return. There are intellectual opportunities associated with EARTH SCIENCES INSTRUCTOR given to candidates with research interests in, or that can Mars exploration. The nation has embarked on an ambi- Now accepting applications for a full-time, tenure-track be applied to, paleontological studies of the Great Plains tious program based at JPL to explore Mars over the next instructor to begin Fall 1999. Starting salary: $38,492- and adjacent northern Rocky Mountain region. few decades, culminating in sample returns. The Divison's $47,608. District application required. Apply by 3/04/99. This full year appointment, renewable up to 3 years, is strength in geochemistry and planetary science provides a Contact Personnel Services. One College Dr., So. Lake being offered at a salary of approximately $30,000 plus strong base of support. Tahoe, CA 96150, (916) 541-4660 x226 or E-mail: benefits. Review of applicants will begin on April 15, 1999 Applications should include a curriculum vitae, a list of [email protected]. AA/EOE. and the fellowship will start on September 1, 1999. Appli- papers published and submitted (with refereed papers cations will be reviewed and considered until the position indicated), a brief essay describing the applicant's TENURE-TRACK FACULTY POSITION is filled. research interests and the program of research he or she EDINBORO UNIVERSITY OF PENNSYLVANIA Applications should include curriculum vitae and the proposes to carry out at Caltech, and the names and The Department of Geosciences at Edinboro University names of three references, submitted to Dr. James E. addresses of at least three references (including e-mail seeks applications for a tenure-track Instructor/Assistant Fox, Chairman, Department of Geology and Geological addresses if possible). Professor with expertise and teaching experience in one Engineering, South Dakota School of Mines and Technol- Applications should be sent to Professor E. M. Stolper, or more of the following areas: remote sensing, soils, ogy, Rapid City, SD 57701. The South Dakota School of Mail Stop 170-25, California Institute of Technology, paleolimnology or quaternary geology beginning August Mines and Technology is an equal-opportunity/affirmative Pasadena, CA 91125, USA. 1999. Salary and benefits are excellent and competitive. action employer and encourages women and minorities to Caltech is an Equal Opportunity/Affirmative Action Applicants should have ability and desire to teach intro- apply. employer. Women, minorities, veterans, and disabled per- ductory geology courses as well as upper level courses in sons are encouraged to apply. area of expertise. Ph.D. in geology required, ABD consid- NORTHERN KENTUCKY UNIVERSITY ered. Preference given to candidate who can integrate PETROLOGIST/MINERALOGIST FORT LEWIS COLLEGE applied technology in teaching and research. Demonstra- Position as a tenure-track Assistant Professor in geology ASSISTANT PROFESSOR OF GEOLOGY tion of excellent teaching skills as part of the interview is begins August, 1999. Ph.D. in geology and teaching expe- Tenure-track position anticipated Fall, 1999. Ph.D. required. rience in geology required. Applicants should possess a required. Primary teaching responsibilities include stratig- In accordance with the terms of the collective bargain- strong commitment to undergraduate teaching and con- raphy, sedimentology, paleontology, historical geology. ing agreement between the State System of Higher Edu- ducting a modest research program. Teaching experience Must be active in research/scholarly work, especially cation and APSCUF, you may be assigned to perform in mineralogy, igneous and metamorphic petrology is undergraduate research. Expertise in petroleum geology, work at off-campus sites and/or provide instruction desirable. Successful candidate will teach introductory environmental geology, hydrogeology, structural geology, through distance education. courses in geology, advanced undergraduate courses and or geophysics desirable. Additional teaching obligations Specifiy Position #170-0892 and send a letter of appli- labs (petrology, mineralogy, optical mineralogy and struc- may include general education courses. Send letter of cation, current vitae, transcripts and names/addresses/ tural geology), lead field trips, and collaborate with faculty application, resume, statement of teaching and research telephone numbers of three current references to Dr. Eric from various disciplines in the development and teaching goals, and names and addresses of three references, Randall, Dean of Science, Management, and Technolo- of integrative science courses. Send letter of application, postmarked by February 15, 1999, to: Dr. Douglas C. gies, Edinboro University of Penn., Department GSA, curriculum vitae, a separate statement of teaching philos- Brew, Department of Geology, Fort Lewis College, 1000 Edinboro, PA 16444. Application Deadline: March 19, ophy and research interests, and the names, addresses, Rim Drive, Durango, CO 81301-3999. Official transcripts 1999. Visit our home page at http://www.edinboro.edu/ phone numbers, and e-mail addresses of three references will be requested of semi-finalists. FLC is an AA/EOE. AA/EOE/M/F/V/D to: Dr. John Filaseta, Chair of Geology Search Committee,

38 GSA TODAY, February 1999 GEOLOGY/MATH — LEE COLLEGE for this position: 1) Knowledge of Quaternary palynological The Math, Engineering and Sciences Division of Lee Col- and/or Quaternary macrofossil research. 2) Knowledge of lege, a public 2-year Community College, located in Bay- Microsoft Access database and Microsoft Excel spread- town, 20 miles East of Houston, Texas, invites applications sheet software on a PC or Macintosh platform and for a regular contract appointment in Geology/Math. The demonstrated skill with ArcInfo or ArcView GIS software. successful candidate will have at least a Master’s Degree in 3) Knowledge of Quaternary paleobotanical and paleocli- Geology or related field and adequate credits to teach matic research techniques and literature in North America. developmental and/or college math. Preference will be 4) Ability to communicate results to other scientists and given to candidates with 18 graduate hours in geography, the public by publication and/or presentation teaching experience at the community college level, a back- This is a TERM position not-to-exceed 13 months with ground in GIS, and a strong demonstrated commitment to the possibility of renewal for up to 4 years with a starting field geology as an instructional tool. Teaching responsibili- salary range of $41,201 to $53,560 depending upon quali- ties include physical, historical, environmental, introductory fications. A complete copy of the vacancy announcement geology and developmental or college mathematics. Off #USGS-CR-99-104-D and application requirements can campus, night and weekend sections may be assigned. be found on-line at or may The starting salary range will be $31,947 to $38,611, be requested by calling Natalie Mashburn at (303) depending upon degrees and experience. Excellent college 236-5900 ext. 362. Interested persons should submit benefits will accrue with this position. Qualified candidates a complete application and college transcripts to: U. S. must submit a current resume, cover letter, copies of appli- Geological Survey, P.O. Box 24046, MS 612, Attn: Per- cable transcripts or evaluation of foreign transcripts (official sonnel Office, Denver, CO 80225. Applications must be transcripts required upon employment) and contact infor- received by February 26, 1999. U.S. citizenship is mation on 3 professional references to: Personnel Office, required. U.S. Geological Survey is an Equal Opportunity Lee College, P.O. Box 818, Baytown, TX 77522-0818; Affirmative Action Employer. Telephone: (281) 425-6875; fax 281-425-6568.

ENVIRONMENTAL GEOLOGY TENURE-TRACK POSITION Consultants ENVIRONMENTAL SCIENCE AND TECHNOLOGY TEMPLE UNIVERSITY GEOSCIENTIST, proven, cost-effective experience, The new College of Science and Technology of Temple ground water, oil & gas, environmental and natural University is undergoing a major expansion of its interdis- resource projects, US and Abroad. Respond (318) ciplinary program in Environmental Science and Technol- 981-4678. ogy. We invite applications for three tenure-track posi- tions, one each in Geology, Biology, and Engineering. Successful candidates will have an interest in achieving Services & Supplies excellence in teaching and research. They are expected to continue or develop an active, externally funded LEATHER FIELD CASES. Free brochure, SHERER research program involving both undergraduate and grad- CUSTOM SADDLES, INC., P.O. Box 385, Dept. GN, uate students. Appointments are possible at any aca- Franktown, CO 80116. demic level, appropriate to experience. Applicants for Associate Professor or Professor must have an externally DON'T KILL YOURSELF with the carcinogenic bromides, supported research program and a substantial publica- like tetrabromoethane for mineral separation. Use water- tions record. based non-toxic high-density agent Sodium Polytungstate. The Department of Geology seeks applications from Density ranges from 1.0 to 3.1 g/ml and up to 4.0 g/ml in field-oriented environmental geologists with specializa- combination with Tungsten Carbide. Sometu. Phone (818) tions in estuarine and coastal processes, sedimentation 786-7838; Fax 818-786-4343; website: www.sometu.com; and stratigraphy, surface water hydrology, surficial pro- e-mail [email protected] cesses, or global cycling. The position is to complement existing strengths in hydrogeology, geochemistry, stratig- raphy, and environmental geophysics. The individual is to teach undergraduate courses in geology and graduate Opportunities for Students courses in their field of specialization. Applicants should send a curriculum vitae, publication Research Grants Available. The Colorado Scientific list, a statement of research interests and teaching philos- Society invites graduate students to apply for research ophy, and the names, telephone numbers, and postal and grants, to be awarded in April 1999. Applicants must be e-mail addresses of four references to the Chair of the enrolled in a Masters or Ph.D. program at an accredited Search Committee, Department of Geology, Temple Uni- college or university. Approximately eight grants, ranging versity, Philadelphia PA 19122. Consideration began on from $500 to $1200 each, will be awarded for field-ori- February 1, 1999 and will continue until the position is ented research on the geology, geochemistry, and geo- filled. physics of the Rocky Mountain region. In addition, grants Additional information may be obtained from: David as large as $1000 are awarded for engineering geology Grandstaff, (215) 20408228, [email protected], or research (with no restriction on the geographic area of www.temple.edu/geology. interest), and one grant as large as $1000 is offered for Temple University is an equal opportunity/affirmative studies of the Heart Mountain Fault in northwest action employer. Applications from women and members Wyoming. Interested students can obtain application of underrepresented minorities are encouraged. forms and grant information directly from the Society web- site at http://shell.rmi.net/~css/ or by mail from the Chair of RESEARCH GEOLOGIST the Memorial Funds Committee, Colorado Scientific Soci- USGS, GLOBAL CHANGE AND CLIMATE TEAM ety, P.O. Box 150495, Lakewood, CO 80215-1405. Dead- The U.S. Geological Survey Global Change and Climate line for applications is March 20, 1999. Team is seeking a Research Geologist, GS-1350-11 to work on an existing project involving the paleoclimatic NASA Planetary Biology Internships. The Marine Bio- interpretation of Quaternary palynological and plant logical Laboratory, Woods Hole, Massachusetts, invites macrofossil records from North America, with an empha- applications from graduate students and seniors accepted sis on the arid and semi-arid western United States. to graduate programs for awards of $2200 plus travel to Applicants must posses a degree in geology plus 20 addi- participate in research at NASA centers and collaborating tional semester hours in any combination of mathematics, institutions for approximately 8 weeks. Typical intern pro- physics, chemistry, biological science, structural, chemi- grams include: global ecology, remote sensing, microbial cal, civil, mining or petroleum engineering, computer sci- ecology, biomineralization, and origin and early evolution ence, planetary geology, comparative planetology, geo- of life. Application deadline: 1 March 1999. For informa- physics, meteorology, hydrology, oceanography, physical tion/applications, contact: Michael Dolan, Planetary Biol- geography, marine geology, and cartography. In addi- ogy Internship, Department of Biology, Box 3-5810, Uni- tion, applicants must have an appropriate Master’s or versity of Massachusetts, Amherst, MA 01003-5810. equivalent graduate degree OR 1 year specialized experi- E-mail: [email protected]. Tel (413) 545-3223. An ence equivalent to the GS-9 level in the Federal service. Equal Opportunity/Affirmative Action Employer. The following knowledges, skills and abilities are desirable

GSA TODAY, February 1999 39 1999 AVAILABLE JUNE unique volume commemorating the AGSA Cordilleran Section Centennial with classic papers on Cordilleran geology and an update CLASSIC by leading geologists in the field. The book highlights the impact of Cordilleran geoscientists and their science on the global CORDILLERAN geologic framework.The editors selected 19 classic papers that made landmark contributions to the understanding of geologic processes. CONCEPTS: Each paper is reproduced together with a contemporary commentary about the status A VIEW FROM CALIFORNIA of the subject today.

PC/MAC- compatible CD includes • detailed full-color images of the San Andreas fault edited by • animation of the tectonic Eldridge M. Moores evolution of the San Doris Sloan Andreas system and Southeast Asian region Dorothy L. Stout valuable • spectacular photographs valuable of the Cordillera and related regions provided by NASA bboonnuuss!! • interesting selection of old California maps commemorating the Cordilleran Centennial, June 1999