CSULB Faculty, Students Present Research At GSA Annual MeetingPublished: December 15, 2010
Seven presentations on geological research projects conducted by CSULB Geological Sciences faculty and students as well as colleagues from other organizations took place recently during the annual meeting of the Geological Society of America (GSA) at the Colorado Convention Center in Denver.
The GSA is one of two major organizations for geologists and researchers in associated fields including archaeology. The annual meeting typically draws between 3,000 and 5,000 attendees, said CSULB associate professor Gregory J. Holk, who was involved in five of the projects. “It’s a great opportunity for students to meet the important researchers in their field.”
Several presentations were based on work done by Holk and others involved in CSULB’s Institute for Integrated Research in Materials, Environments, and Society, a state-of-the-art lab where faculty and students from the College of Natural Sciences and Mathematics and the College of Liberal Arts, as well as other outside researchers, conduct analyses relating to societies, environments and materials.
Holk described his students’ projects.
Judy Bernal, now a CSULB anthropology master’s student, discussed undergraduate experiments that investigated ancient technologies of making pottery and tiles. “Many of the chemical reactions that occur during that process are the same chemical reactions that occur during the metamorphism of rocks,” Holk said, noting that CSULB Anthropology professor Hector Neff also collaborated on this project.
Melissa Bernardino spoke about a project begun by Jacqueline Chavez, now a master’s student. Both of are California State University Sally Casanova Pre-Doctoral Scholars who are preparing to earn doctoral degrees following graduation from CSULB. Both did summer research at Caltech—Chavez worked there in 2008, while Bernardino was a 2009 Caltech Minority Undergraduate Research Fellow.
“At around 57 million years ago there was an episode of very rapid global warming and global temperatures,” Holk explained. “The Paleocene-Eocene Thermal Maximum is the closest analog in the geological record to what is happening now with respect to greenhouse gas-forced global warming. In order to understand what is happening now, we need to go back and try to understand similar events in the geological past.”
Chavez studied exposed carbonate rocks in the Santa Monica Mountains derived from coral reefs that existed during the thermal maximum period, while Bernardino worked in San Rafael Mountains near Santa Barbara, said Holk, who contributed by studying carbon isotopes from the rock samples. “It’s potentially turning out to be a significant project in that we’re the first to document this event occurring in Southern California,” said Chavez. Katherine Whidden of the U.S. Geological Survey in Denver also participated.
Two projects studying the Portuguese Bend landslide area of the Palos Verdes Peninsula were done through CSULB’s Geoscience Diversity Enhancement Project (GDEP), funded by a $1 million grant from the National Science Foundation to encourage underrepresented minority students to pursue college degrees and careers in geology, physical geography or archaeology.
One project involved Geological Sciences’ Matthew Becker, who holds the Conrey Chair in Hydrogeology; Holk’s graduate student Gabriela Valenzuela; two local high school and community college students; and retired USC Professor Robert Douglas, now with the Abalone Cove Landslide Abatement District.
“This project is unique in that we’re utilizing stable isotopes to monitor the circulation of groundwater through a landslide,” said Holk, who is working with Becker to study where the water comes from. They can identify chemical differences between rainwater, garden irrigation water and seawater that seeps in from the ocean. “This project is just the beginning of a longer-term monitoring effort. Matt Becker, Bob Douglas and I have discussed strategies for ensuring that there’s a long-term observation of this system because it provides us with a unique opportunity to understand the dynamics of landslides and the relationship of water and slip on the landslide.”
Graduate student Conni Stuehler presented the second related Portuguese Bend project, which is studying the bentonite clays that serve as the landslide’s slip surface. “Nobody has characterized the mineralogic composition of the Palos Verdes bentonites, which are volcanic rocks that have been altered to dominantly clay,” Holk said. Some clays can absorb water and expand, while others don’t expand, so it’s important to know how much of these substances are in the clay. They also found other minerals called zeolites, which also expand, so this ongoing project will provide a greater understanding of the slide. Through GDEP, several other local students and educators also took part.
Holk, an expert on how surface water moves through and affects the earth’s deep crust, presented his own ongoing research on how certain types of schists, which are metamorphic rocks that were changed through heat and pressure, are found so far inland in Southern California and Arizona. By examining the chemistry of water found in the rocks, Holk can tell whether the water has percolated down from extensional (stretching) faults or come up from below through thrust faults caused by subduction. Holk is working with Carl Jacobson of Iowa State University and Marty Grove from Stanford University.
CSULB assistant professor Lora Stevens, who studies paleoclimatology, or climate history, has been working with Morteza Djamali and Jacques-Louis de Beaulieu of the Institut Méditerranéen d’Ecologie et de Paléoécologie in Aix-en-Provence, France, to study the hydroclimatic history of Lake Urmia, a large, ancient saline lake in northwestern Iran. The team is examining test cores drilled for a new bridge at the lake that contain soil up to 200,000 years old. “There are only a handful of sites that you can do this around the world, so this is a special place,” she said. Their goal is to eventually provide information about differences in climate changes that occurred during limited human activity compared with more recent climate shifts.
CSULB professor Stanley C. Finney, who also is chair of the International Commission on Stratigraphy (ICS), led a presentation on the commission’s ongoing work in establishing the International Chronostratigraphic Chart. “From the units of that, we recognize our geologic time scale and the same names (e.g., Jurassic, Paleocene, etc.) The time scale is a fundamental way of discussing geology, but when the units of it were established through the 1800s and early 1900s, there were different units used on different continents. There also were no definitions of the actual boundaries between the different units,” he said. The ICS uses features in rocks including fossils, changes in the earth’s magnetic fields and other characteristics to determine the time frame for a particular age, epoch or period. “Just last year we voted on and made a decision on formally defining the Jurassic period for the first time, for example.”