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I was born in California, USA in the mid 50's.

My siblings and I grew up in various communities in Southern California. My father was a teacher before he retired, and we moved from town to town as he found better school districts for which to work. At the time of my entering middle school, we had settled in a community called La Canada-Flintridge about 20 miles north of downtown Los Angeles. I graduated from La Canada High School in 1973.

Higher Education[edit]

I entered the University of Southern California in Los Angeles, and paid for the education partly with state scholarship funds and the rest with money I earned by working. My most interesting undergraduate job was as the geochemistry lab assistant to Dr. Lawford Anderson, where I performed chemical analyses of igneous and metamorphic rock samples to 'fingerprint' the various rocks and thereby establish identification links between tectonically separated rock bodies. I graduated in 1979 with a Bachelor's degree in Earth Sciences.

After an 8-month stint doing mineral exploration with Conoco in Wyoming, I started my post-graduate education in Earth Sciences at the University of Arizona with Dr. George Davis as my thesis advisor. My thesis topic was to describe and explain the presence of a small allochthonous block of imbricated metasediment slivers in the pass between two mountains near Tucson, Arizona. There was considerable controversy at the time in explaining the geology around these mountain ranges, with one camp explaining the observed features using a pure thrust-fault interpretation, and the other camp explaining the features using a pure gravity-glide interpretation. My work showed that evidence for both mechanisms were present. Compressive thrust faulting created the imbricate thrust geometries, and subsequently the stack of thrust plates was 'beheaded' by a gravity glide decollement fault, thus transporting the block of metasediments onto igneous metamorphic basement. The upper plate thrust faults were truncated at the underlying gravity glide decollement.

Work Experience[edit]

After graduation from the University of Arizona in 1981, I started to work for Exxon's Western Production Division office in Los Angeles as a petroleum geologist. My first assignments were monitoring the development plans of the operators of the giant Prudhoe Bay field on the North Slope of Alaska. In 1986, Exxon moved the Alaska Interest Organization (AIO) to downtown Houston, Texas. I stayed with AIO as a geologic computer application specialist until 1989, when I was transferred to the Production Company's Central Division where I continued as a geologic computing specialist.

Exxon went through various reorganizations, but my job discription remained largely the same. One year the Corpus Christi office was closed and those employees were brought to Houston and added to Central Division. A few years later the Midland office was closed and those people were also merged with our group, creating the Houston Production Organization (HPO). At HPO, my job slowly transformed from computing support back to interpretation and analysis, and in the late 90's I was reassigned as a geologist within HPO's Field Study group. While in this group, I performed the majority of the well log analysis for the group's field studies, and began to get involved with the growing geologic modeling capabilities of the corporation.

At the end of 1999, Exxon and Mobil merged to become ExxonMobil. The HPO Field Studies team had been such a success on domestic US fields that management decided to create a world-wide Field Studies Group (FSG) in the Production Company's Central Technology organization. The HPO Field Studies team formed the core of the new FSG. I was assigned as one of the new group's Geologic Modeling specialists, and my skill area affiliation was changed to reflect that change in emphasis.

In 2003 I was transferred to the company's Research Lab in Houston. I currently work in the Geologic Modeling group at the Lab, and my research focus is on geologic modeling in carbonate rocks. Besides research, my duties also include instructing a portion of a field course on carbonate stratigraphy and modeling, mentoring employees who are new to geologic modeling, consulting on planning for upcoming projects involving geologic modeling, and giving guest lectures in other courses, seminars, and industry conventions.


I have been married to Alis Penalosa from Caracas, Venezuela since 1998. I have two daughters, Denise (born 1984) and Jaimee (born 1988) from a previous marriage.


I am an amateur musician. I play bass with a local group called the Kingwood Garage Band (KGB). We perform music of most genres, from 60's Folk to Blues to Country to 90's Rock&Roll. We have weekly appearances at a local barbecue restaurant, and monthly appearances at a wine shop and at a bistro within a few miles of home.

Wikipedia Posting Areas[edit]

Ice Ages, Climate Changes Throughout Geologic History, Driving Factors[edit]

My work expertise revolves around describing and predicting the responses of calcite-secreting marine organisms and depositional systems to changes in environment. Those environmental changes include sea level changes, global warming and cooling trends, rainfall rates, evaporation rates, plate tectonics, and tides. One of the major responses visible in marine carbonate systems is the reaction to ice ages and the associated changes in water depth. These sea level changes occur worldwide at the same ages, and are therefore very valuable for predictive models of carbonate rock building and erosion. I have a lot of direct knowledge of the effects of climate change on the rock record, having stood upon and studied many of the critical outcrops and studied these same changes as revealed in well penetrations.

I am therefore interested in the root causes of these climate variations.

Prevailing theories of climate change involve 2 main influences.[edit]

The strongest influence is the change in the amount of sunlight that falls in the high temperate latitudes where major glaciation takes place. These changes in sunlight strength are predicted very well using a system of equations that describe the changes in Earth's orbit and angle of axis inclination through time (see Milankovitch cycles).

The other influence is really a mechanism that reinforces the solar variations. As plate tectonics moves the continental land masses around the Earth's surface, sometimes the plates cluster near the equator and at other times cluster nearer the poles. Today, much of the Earth's landmass is concentrated in the northern hemisphere, which gives an opportunity for glaciers to accumulate that does not exist when the continents are clustered at lower latitudes. However, it requires lower summertime temperatures to trigger that glaciation. Cooler summers melt less of the winter snowpack, and if there is less snow melting than snow accumulation for several years in a row, a glacier will form.

Continental drift also affects the paths of the major ocean currents. Ocean currents exist to distribute the Earth's solar energy. When there are no barriers to east-west ocean flow, like exists today all around the Antarctic continent, continuous circumglobal currents are established (see Antarctic Circumpolar Current). However, today there is a narrow connection between North America and South America that prevents the establishment of a circumglobal equatorial ocean current connecting the Atlantic and Pacific oceans. Similarly, Africa is currently joined to Europe/Asia, preventing currents from the Indian Ocean through the Red Sea into the Mediterranean and then into the Atlantic. When continents prevent east-west flow, the currents are diverted to the north and south (like the Gulf Stream) and carry that tropical heat to higher latitudes, making the climate in higher latitudes warmer that it would be if the currents had not been diverted.

GregBenson 20:33, 27 December 2005 (UTC)