March 2003

From Geological Society of America

GSA Southeastern and South-Central Sections to meet this week in Memphis

Boulder, Colo. – Geoscientists from around the country will gather this week in Memphis at a joint meeting of the Southeastern and South-Central Sections of the Geological Society of America. Hosted by the Department of Earth Sciences at the University of Memphis, the meeting takes places March 13-14 at the University of Memphis Conference Center. Approximately 600 scientists are expected to attend.

The program includes talks on local and regional geology, as well as talks on subjects of broad interest such as paleontology and planetary science. The Geological Society of America invites journalists to attend any session of interest, interview scientists, and visit the exhibit area. Information on complimentary media registration and procedures for arranging interviews during the meeting follow the program highlights below.


Dinosaurs and America's Interior Sea
During the last age of dinosaurs approximately 80 million years ago, the interior of North America was underwater, creating a seaway from the Arctic to the Gulf of Mexico. It ran down through Canada, the Dakotas, eastern Montana, Colorado, Wyoming, Kansas, Nebraska, Texas, and Mexico. David Schwimmer of Columbus State University will look at the origins of the dinosaurs living on the eastern side of the seaway. They appear to be very similar to those on the west side and both appear to have a common Asian ancestry. So how did those living on the east side of the seaway get across? Schwimmer will discuss relationships among the eastern carnivores and the likelihood that they arrived before the seaway flooded the continent.

Thursday, March 13, 4:20 p.m., Fogelman Executive Center 219.
View abstract at

David R. Schwimmer
Department of Chemistry and Geology
Columbus State University
[email protected]

Early Earth and Large Asteroid Impacts
Very early in Earth's history, 3.8-3.2 billion years ago, the young planet was bombarded a number of times by large asteroids. Gary Byerly of Louisiana State University and Donald Lowe of Stanford University began publishing studies of these impact events in the mid-1980s. For the first time, Byerly will discuss a synthesis of findings published in the last year and their implications, drawing on his own work plus that of colleagues at LSU, Stanford, UCLA, and UCSD. It now appears that three or more clusters of large impact events took place, profoundly influencing the physical and biological evolution of early Earth. Considering that a lunar impact cataclysm occurred in the same timeframe, Byerly suggests that evolution of the inner solar system might best be characterized by long stable periods separated by major clusters of asteroid impacts, rather than a long continuous decline in impact activity over time.

Thursday, March 13, 10:20 a.m., Fogelman Executive Center 219.
View abstract at

Gary R. Byerly
Department of Geology and Geophysics
Louisiana State University
[email protected]

Mapping Asteroid 4 Vesta
Asteroid 4 Vesta is one of the targets of NASA's upcoming DAWN spacecraft mission, scheduled to launch in May 2006. It is the third largest asteroid in the solar system, measuring approximately 500 km in diameter. Mike Kelley of Georgia Southern University will report on his studies of what appear to be fragments of the asteroid, referred to as Vestoids, which were ejected during large impact events early in solar system history. The more that is known about Vesta and its fragments before the NASA mission, the more sophisticated the science questions that can be addressed when the spacecraft reaches the asteroid in July 2010.

Thursday, March 13, 8:20 a.m., Fogelman Executive Center 219.
View abstract at

Michael S. Kelley
Department of Geology and Geography
Georgia Southern University
[email protected] 912-486-7913

Seismic Hazards: How Much Shaking Might We Expect?
Recent geologic work near Memphis and in southeastern Arkansas suggested the presence of three underground faults, dating back 10,000 years to a period of Earth's history known as the Holocene. Chris Cramer of the U.S. Geological Survey in Memphis will discuss new estimates of ground motion that might be expected should earthquake activity occur on these faults. Scenario seismic hazard maps suggest that an earthquake measuring 6.5 on either of the two faults near Memphis could generate peak ground accelerations in excess of 0.5 g over much of Shelby County and in downtown Memphis. While the likelihood of such an event is very small, the ground motions are similar to those expected from a repeat of the 1811-1812 earthquakes on the New Madrid seismic zone.

Thursday, March 13, 2:40 p.m., Fogelman Executive Center 215.
View abstract at

Chris Cramer U.S. Geological Survey [email protected] 901-678-4992

A Victim of Piracy? Why the Tennessee River Runs North in Hardin County
Robert Self of the University of Tennessee-Martin will shed some new light on why the Tennessee River takes an unusual northward course in West Tennessee. Clues as to why the river doesn't simply flow south to the Gulf of Mexico or west toward the Mississippi lie in the flow of the ancestral Tennessee River. Based on geologic studies of river terraces, Self proposes that approximately five million years ago, the ancient Tennessee River flowed westward, following the modern Hatchie River and flowing into the Mississippi north of Memphis. Later a shorter northward flowing stream may have intersected the Tennessee River. In a process known as stream piracy, that stream may have diverted the Tennessee River into its own northward flowing channel.

Friday, March 14, 1:20 p.m., Fogelman Executive Center 219.
View abstract at

Robert P. Self Department of Geology, Geography, and Physics University of Tennessee-Martin [email protected] 731-587-7444

** View the entire scientific program at**


Eligibility for complimentary media registration is as follows:

–Working press representing bona fide news media with a press card, letter, or business card from the publication.

–Freelance science writers, presenting a current membership card from NASW, ISWA, regional affiliates of NASW, or evidence of work pertaining to science published in 2001 or 2002.

–Public Information Officers of scientific societies, educational institutions, and government agencies.

Media representatives may register at the main meeting registration desk located in the third-floor lobby of the Holiday Inn. (The Holiday Inn is directly across from the Fogelman Executive Center on Central Avenue.) Registration will be open Wednesday, March 12, from 4-8 p.m., Thursday, March 13, from 8 a.m.-5p.m., and Friday, March 14, from 8 a.m.-12 noon. All media registrants will receive a name badge and the program/abstract book.

Media registrants may arrange on-site interviews after attending the session in which the talk is given or by leaving a note at the GSA Registration Desk requesting an interview before or after the talk. Interested media unable to attend may telephone the Registration Desk at 901-678-1511 and leave a message requesting a callback from the speaker.

For additional information before March 13, contact Ann Cairns, GSA Director of Communications, at 303-357-1056. During the meeting, March 13-14, contact the GSA Registration Desk at 901-678-1511.

This article comes from Science Blog. Copyright © 2004

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