Geology, Climate and Global Warming

Craig Peterson’s Inside Scoop, ClearChannel Radio’s Number One Saturday Radio Show in the Boston Market

Pat Abbot Professor Emeritus of Geology at San Diego State University Department of Geological Sciences speaks with Craig about Climate, Global Warming and What Geology tells us.

- Climate and change go together. Climate changes on every time scale from millions of years to thousands to decades, etc.
- Many people do not understand the difference between climate and weather. Weather is day-to-day and is always changing. For some odd reason, every heat wave or cold spell is seen by some folks as unusual, a rarity, unexpected, and other such silliness.
- The current topic of global warming is definitely worth understanding.
- The global scientific community is overwhelming agreed that average annual surface temperature on the Earth is the warmest it has been in over one thousand years.
- Some of the scientists most vocal about global warming not being real are ignoring facts to focus on a personally favored view; some of them are doing it for publicity and/or to gain more funding.
- At present, the Earth is undergoing a natural warming, but piggybacked on top of this trend is an even greater amount of warming due to human activities.
- Carbon dioxide additions to the atmosphere have accelerated as we have burned ever more oil, natural gas, coal and wood. The expected greenhouse warming is actually less than it ought to be. The dominant thought now is that the excess heat is being stored in the ocean and thus much of our excess will be dealt with by future generations.
- It has long been popular to state that the US is the main producer of CO2. However, in a matter of months China will pass us up.
- The much argued Kyoto Treaty exempts “developing” countries from greenhouse gas restrictions. China and India are near the top of the list of CO2 emitters but are not required to do anything. Is Kyoto really about climate?
- The biggest part of the problem is the one not talked about anymore — the explosive growth in the human population — it reached 3 billion in 1960, 4 in 1974, 5 in 1987, 6 in 1999, and has now passed 6.6.billion. About 30% of the world population is below the age of 15 and has not yet done their breeding. The soaring population will all use energy thus adding to global warming.
- Other gases also add to the greenhouse effect. For example, methane (CH4). Humans release CH4 via rice production and cattle raising (>1 billion cows now). Methane is 21 times as potent as CO2 as a greenhouse gas.
-- World population and energy usage both are on unstoppable growth trends. Thus global warming will increase. The big worries are not how the rising temperatures affect us directly but how they change rainfall and agriculture.
- It sure would be nice if technologists could figure out a way to make CO2 capture into a profitable business. I have more confidence in technological creativity than in the abilities of the world’s political leaders and bodies.

Pat AbbottProfessor Emeritus of Geology at San Diego State UniversityDepartment of Geological Sciences
Author of textbook Natural Disasters (6th ed.) published by McGraw-Hill.

Giant Meteorite Crater Discovered in California

A space rock the size of three football fields may have slammed into California more than 35 million years ago, according to a team of scientists that includes a high school student.
The proposed impact may have created the giant 3.4-mile-wide (5.5-kilometer-wide) craterlike formation that the team found buried 4,900 to 5,250 feet (1,490 to 1,600 meters) below sea level west of Stockton, California.
Rocks in the potential crater date to about 37 to 49 million years ago.
The formation resembles an impact crater, the researchers said, but they are continuing to analyze rocks from oil exploration wells dug in the region for telltale signs of a collision.
Jared Morrow, an assistant professor of geology at San Diego State University, presented preliminary details of the discovery earlier this month at the Lunar and Planetary Science Conference in Houston, Texas.
Samuel Spevack, a senior at Grossmont Middle College High School in El Cajon, California, is leading the continuing analysis and will discuss the project next month at a meeting of the American Association of Petroleum Geologists in Long Beach.

Science Fair
Samuel's father, Bennett Spevack, is a geologist with ABA Energy Corporation in San Diego. He first spotted the crater while examining seismic survey data of the Central Valley region.
"It looked interesting because it was circular," he said. "My son saw it and expressed interest in figuring out whether it might be an impact crater."
Samuel presented seismic data of the proposed impact crater at the Greater San Diego Science and Engineering Fair in 2005.
The data clearly shows a circular structure carved out of an ancient sea bed.
The high school student won an award at the fair, but the scientific community requires additional rock evidence before it can verify a new impact crater.
Samuel Spevack partnered with Morrow for the continued analysis. The researchers are searching for deformities in the rocks, such as shocked quartz, that require the high-shock pressure of impacts in order to form.
"We've found a few grains that exhibit some features of shock, but there still needs to be other searching and peer reviewing," Samuel Spevack said.
David Kring is an expert on impact craters at the Lunar and Planetary Institute in Houston. He said the presentation at the conference was appropriate for this stage of the crater analysis, but more rock analysis is required "to confirm an impact origin."
"The reason that's important is [that] there are a lot of geologic processes that make circular structures," he added.

Headline Impact
According to Bennett Spevack, if a space rock did crash into California's Central Valley, it would have created a 1,500-megaton explosion.
"This is not big enough to have wiped out the dinosaurs, but I guess it certainly would have made headlines if one this size would hit San Francisco," he said.
Scientists believe California's Central Valley was underwater at the time of the possible meteorite strike. If so, the impact may have also triggered a tsunami.
The proposed impact crater, called the Victoria Island structure, is being added to a database of suspected impacts. It joins the 0.8-mile (1.3-kilometer) Cowell structure to the north as California's only potential impact craters.
Neither structure is confirmed.
"If [the Victoria Island structure] can be proven, it'll be the first one in California," Bennett Spevack said.
Source National Geographic News

ONLINE SEMINAR
3-D seismic, well log, and petrographic analyses of the Victoria Island structure, a potential buried impact crater, San Joaquin county, California

Tom Rockwell - UCSB Distinguished Alumni 2007

Professor Tom Rockwell has been selected as the Distinguished Alumni for 2007 by the Department of Earth Science, University of California Santa Barbara. Tom recieved his Ph.D. from UCSB in 1983. Each year, the department of Earth Sciences selects two alumni, one from academia and the other from the public sector or industry, to join a select group of their most distinguished alumni. Tom has been here at SDSU for 24 years, his research focus has been split between general neotectonic studies and the more specialized subfield of paleoseismology. He has advised over two dozen Master and Undergraduate Students.

Robert McEuen, SDSU Geophysicist, Passes Away at 77

Robert B. McEuen

McEUEN, ROBERT B. Robert B. McEuen, age 77, of Denver, CO, formerly of San Diego, emeritus geophysics professor, SDSU, died March 8, 2007. He is survived by Cecily, his wife of 52 years; daughters, Mary (Ron Kenny) McEuen, Denver, CO, Rebecca (Jeffrey) Wilcox, Minneapolis, MN, Amy (Leon Hinz) McEuen, Springfield, IL; brother of Carol (Jack) Feeney, Long Beach, CA; a niece and nephew; eight grandchildren; and a grandnephew.

Memorials may be made to Parkinson Association of the Rockies, 1420 Ogden St., Ste. 201, Denver 80218 or Hospice of Metro Denver, 501 Cherry St., Ste. 700, Denver, 80246.

Published in the San Diego Union-Tribune on 3/18/2007.

SEMINAR - Tyrone Rooney

My current research concentrates on the Main Ethiopian Rift from the perspective of geochemical and petrographical variation in the central rift. This central zone is considered a key transition zone between the continental rifting to the south and seafloor spreading to the north. My research investigates key magmatic processes associated with this transitional rifting and evaluates geochemical data in an extensive geophysical framework. This synthesis of geochemical, petrographic and geophysical data at this important location is a primary objective of the EAGLE project that sponsors this work.

Abstract
The East African Rift system is the archetypal example of continental rupture and has global significance in understanding extensional plate tectonic processes. We concentrate on the central Main Ethiopian Rift, which lies between the thicker continental crust in Southern Ethiopia and the thin predominately basaltic crust of the Afar Depression. We utilize Quaternary basaltic lavas erupted in tectono-magmatic fault belts to probe the source of rift magmatism and establish a connection between deeper mantle processes ( e.g. mantle plumes) and continental rifting. This study has also focussed on the relationship between magmatic intrusion in the continental lithosphere and extension. These geochemical results are combined with geophysical studies to produce an integrated geodynamic model for the progression of continental rifting along the Main Ethiopian Rift and call into question the concept of a simple transition between continental rifts and sea floor spreading centers.

Tyrone's seminar title: "An integrated approach to continental breakup: insights from central Ethiopia "; Wednesday the 21st of March 2007

March Crossword Puzzle - Paleontology

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SEMINAR - Bridget Smith-Konter

Abstract
January 9, 2007 marked the passing of 150 years of relative seismic quiescence along California’s central and southern San Andreas Fault System (SAFS). For an active fault system with earthquake repeat times averaging roughly 150 years, the SAFS is likely primed for another major, and potentially devastating, seismic event. In an effort to identify inherent stress behaviors of individual fault segments of the SAFS, a 3-D time-dependent deformation model is used to simulate stress evolution throughout the earthquake cycle. The model spans the last 1000 years of earthquake history and combines an up-to-date set of paleoseismic, geologic, and geodetic constraints. Interseismic Coulomb stress rates generated by the model range from 0.2 to 7.2 MPa/100yrs and reflect variations in slip rate, fault orientation, and locking depth. Assuming a prescribed slip history based on paleoseismic evidence and the historical earthquake record, the model can also be used to estimate the magnitude of accumulated Coulomb stress on each fault segment spanning multiple earthquake cycles. These simulations reveal an evolving stress field through time, and in particular, a significant level of accumulated stress (~7.8 MPa) along the southernmost portion of the San Andreas (Coachella segment) at present day, where major earthquake activity has been absent for over 300 years. While models of this nature are highly dependent on an assumed time and slip history, they provide a quantitative foundation for advancing our ability to recognize zones of elevated seismic risk.

Bridget's seminar title: "Historical Deformation and Stress Evolution of the San Andreas Fault System"; Wednesday the 7th of March 2007

News - The Daily Aztec

Future of Earth's climate depends on the past
By: Maureen Moses, Contributor
Source: The Daily Aztec - Issue date: 3/1/07 - Section: Science & Technology

Scientists at San Diego State are researching an ancient global warming event in hopes of providing information that can help accurately predict modern global warming changes.

Stephen Schellenberg, Ph.D., a professor in the geological sciences department, and the students in his lab are researching previous global warming events to get an idea of how the planet has responded in the past. He's researching an intense warming event that occurred 55 million years ago, known as the Paleocene-Eocene Thermal Maximum. During this event, massive amounts of carbon and other greenhouse gases were released into the atmosphere, causing a rapid increase in global temperature. This increase occurred during the course of thousands of years, and the Earth's climate took tens of thousands of years to recover from the influx of greenhouse gasses.
The information obtained from these experiments about the Earth's climactic history is used to assess how the Earth responds to the influxes of greenhouse gasses. Schellenberg and his team are looking at the PETM event carefully because it is similar to present-day global warming. Both the PETM and today's global warming represent events where massive amounts of greenhouse gases are poured into the atmosphere in a short amount of time. "The PETM represents the best analog in terms of rate, and still, it took thousands of years, and we'll probably reach the same amount of carbon in hundreds of years," Schellenberg said.Schellenberg and one of his graduate students, Elizabeth Landau, are trying to discover more about this event by analyzing fossils recovered from the Ocean Drilling Program, a research cruise that travels the world gathering samples from the seafloor.
Landau's research on the PETM is based on these samples as well as other samples that come from an international archive of sediment cores. She is looking specifically at how organisms called Ostracodes were affected before, during and after the PETM, giving insight to how living organisms changed with respect to their environment. Their research method is two-fold; after obtaining the samples, the tedious process of separating the individual organisms by species from the sediment occurs, and the bodies of the Ostracodes are analyzed by hand. The scientists are looking for evidence of a poor living environment. Then, a chemical analysis will be done. Because the ocean acts like a sponge and absorbs a large portion of what is in the air, the chemistry of the ocean changes. By adding greenhouse gases such as carbon, the ocean becomes more acidic, making survival for any living organism much more difficult. Under the microscope, it's clear that there was degeneration in the Ostracode bodies throughout the PETM. The difficult living environment forced some species to have less robust body physiologies and sent others into extinction. "We can create a baseline of temperature changes based on who's thriving and who's not and by comparing them to modern species," Landau said. The surviving PETM Ostracode species present today have been used to determine the ancient temperatures throughout the PETM, chronicling the changes. The current estimation of the temperature change was about 5 to 7 degrees (Celsius).
The final stage in Landau's graduate research with Schellenberg will be a chemical analysis to determine what PETM-age Ostracodes are made of. Some atoms, although they may have the same names, come in different varieties, such as Carbon-14. This is used to determine the age of ancient artifacts, although the majority of this element is Carbon-12. These atoms are called isotopes and are distinguished by varying weights. When the temperature of the Earth changes, the isotope used in the organism's body changes as well.
The results of this final stage are pending, but based on the overwhelming amount of paleoclimate isotope data, it is unlikely that her research would be inconsistent with past results. Schellenberg is providing detailed pieces of information that describe what happened to the Earth in the past. To better understand the current global warming trends on Earth today, it is imperative to thoroughly assess how the Earth responded to a similar event in the past. By studying organisms' responses to their environment, Schellenberg and his lab can create a timeline of when major changes in Earth's temperature, oceans and ocean circulation patterns occurred and how long it took for Earth to recover. All the climate models in use today take this paleoclimate data into account. Ultimately, one lesson that can be taken away from the PETM is that the Earth is resilient and it recovered from all the greenhouses gases emitted into the atmosphere, but that took a long time. "Eventually, the Earth will reach a stable point," Landau said. "It might not be a place where we can live or where animals can live, but it will recover."