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March 6 AGS Meeting: Thomas Ewing: A Scenic Tour of the Subsurface of the Austin Area

  • Bureau of Economic Geology, ROC Conference Room, 10100 Burnet Road Austin Texas, 78758 (map)

A Scenic Tour of the Subsurface of the Austin Area (Bastrop-Marlin); Milano Fault Zone and Cretaceous to Eocene Stratigraphy 

By Thomas E. Ewing, Frontera Exploration Consultants, San Antonio TX 78259

A recent project in support of groundwater modeling in the area east and northeast of Austin has allowed a good look at regional stratigraphy and structure in the eastern capitol area. Noteworthy items include:

  • Shelf edges of the Lower and Upper Edwards
  • Northeast thickening of the Eagle Ford
  • Austin carbonate bank and the Waco Channel
  • Enigmatic shelf sandstones
  • Milano Fault Zone - en echelon grabens
  • Simsboro Sand - Thickens in graben fill indicating fault movement

This talk will be a preliminary overview, a paper on the fault system will be presented at GCAGS in the fall.

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Dr. Thomas Ewing is a geoscientist with over 33 years of experience in hydrocarbon exploration and research. He is a Registered Professional Geoscientist in the State of Texas (#1320) and an AAPG/DPA Certified Petroleum Geologist (#4538), and holds certification #1610 from SIPES. He received a B.A. in Geology from the Colorado College (1975), an M.S. in Geochemistry from New Mexico Institute of Mining and Technology (1977), and a Ph.D. in Geological Sciences from the University of British Columbia (1981).

Dr. Ewing was a research geologist for four years at the Texas Bureau of Economic Geology in Austin, working on Gulf Coast geopressured reservoirs, serving as a co-author of the "Atlas of Texas Oil Reservoirs", and compiling the Tectonic Map of Texas.   He is now a partner in Yegua Energy Associates, LLC

Tom has published over 75 papers and abstracts. Among other awards, he has twice received the Gulf Coast Section AAPG Levorsen Award (1982 and 1999), and has received the AAPG Distinguished Service Award. He has written articles on Gulf Coast geology and hydrocarbons, the geology and tectonics of Texas, and history and urban geology of the San Antonio area. He wrote the popular guidebook “Landscapes, Water and Man: Geology and Man in the San Antonio Area” published by the South Texas Geological Society in 2008.

In his spare time, he leads field trips in South Texas, and directs a 60-voice German men’s chorus, the San Antonio Liederkranz.