VVOL.OL. 114,4, NNO.O. 3 A PPUBLICATIONUBLICATION OOFF TTHEHE GGEOLOGICALEOLOGICAL SSOCIETYOCIETY OOFF AAMERICAMERICA MMARCHARCH 22004004 CO2 as a primary driver of Phanerozoic climate, by Dana L. Royer, Robert A. Berner, Isabel P. Montañez, Neil J. Tabor, and David J. Beerling, p. 4 Mann Mentors Program, p. 21 GeoVentures 2004, p. 24 VOLUME 14, NUMBER 3 MARCH 2004 Cover: A polar, circum-Pacific landscape from GSA TODAY publishes news and information for more than the early Late Cretaceous (Turonian, ca. 90 Ma). 18,000 GSA members and subscribing libraries. GSA Today An early-autumn aurora borealis casts a blue lead science articles should present the results of exciting new glow on the landscape, which includes an research or summarize and synthesize important problems or active volcano. A champsosaur is visible issues, and they must be understandable to all in the earth science community. Submit manuscripts to science editors catching its freshwater prey against a backdrop Keith A. Howard,
[email protected], or Gerald M. Ross, of representative angiosperms, conifers, and
[email protected]. cycads. Geologic evidence suggests that the GSA TODAY (ISSN 1052-5173 USPS 0456-530) is published 11 Turonian was a time of globally warm temper- times per year, monthly, with a combined April/May issue, by The atures and elevated levels of atmospheric CO2. Geological Society of America, Inc., with offices at 3300 Penrose Art by Rebecca Horwitt. See “CO2 as a pri- Place, Boulder, Colorado. Mailing address: P.O. Box 9140, mary driver of Phanerozoic climate,” by Royer Boulder, CO 80301-9140, U.S.A.