OSU Geology Newsletter 2018.docx

8 Guadalupe Mountains Field Trip An OSU carbonate field trip was run to the Guadalupe Mountains of west Texas and Southeastern New Mexico over Fall Break, October 19-‐22. The trip was lead by Jay Gregg and Mike Grammer for the graduate students in the Advanced Carbonate Petrology & Geochemistry class as well as other carbonate students in the School. During the trip we visited the Permian Capitan reef, back-‐ reef, and basinal facies, as well as a half-‐day excursion through Carlsbad Caverns. After a full day drive to Carlsbad the group stayed at Stevens Motel in Carlsbad, the classic motel that has hosted innumerable geology field trips over the past 60 years or more. The first morning was spent on the Tansill-‐equivalent upper Capitan Reef exposure at the mouth of Dark Canyon, just south of Carlsbad. After about a half hour on the exposure a field trip from University of Kansas pulled up. Apparently the BPSoG was not the only group who thought that this was a good weekend to spend in the Guadalupes! Continuing into Dark Canyon both proximal and distal back reef outcrops in the Yates and Tansill formations were visited. These contain partially to completely dolomitized microbial laminates, pisolites, evidence of evaporates and beautifully exposed teepee structures. The afternoon of the first day was spent touring Carlsbad Caverns. Day two of the field trip started with a visit to road cuts of the Castile Anhydrite followed by a visit to McKittrick Canyon. Here the students hiked the famed “Reef Trail” up the face of the Capitan Reef. They had an assignment to complete for the carbonate diagenesis class. Drs. Grammer and Gregg, having both undergone recent knee surgery, took the ‘easy’ trail up the canyon to the stone lodge built by the famous petroleum geologist, Wallace Pratt, in the early 20th century. It was Wallace Pratt who donated 5,632 acres, including McKittrick Canyon, to the people of the United States, forming the core of Guadalupe Mountains National Park. Mr. Pratt was not at home but Mike and Jay had a nice time sitting on his front porch. The afternoon of day two was spent visiting road cuts of the fore-‐ reef and basinal facies as we drove through Guadalupe Pass. This included excellent exposures of calcareous shale source beds (now unconventional reservoirs) and conventional sandstone reservoirs in the Delaware Mountain Group. The Field trip ended on the Salt Plains west of the pass with a spectacular view of the Capitan and Goat Seep reefs and adjacent back reef- ‐facies exposed on the Guadalupe escarpment. As the sun went down at the end of the day the field trippers drove back to Carlsbad for supper and a final night at Stevens Motel. The next morning the long journey back to Stillwater was started. If your company is interested in organizing an excursion to the Guadalupes, a must for anyone working the Permian Basin, contact Mike Grammer or Jay Gregg. We can put together a professional field trip of two to five days duration (not including travel) and our rates will be a lot lower than that charged by the commercial outfits. Especially for alumni and friends! —Jay Gregg Dr. Grammer and students posing in front of a panorama of the Capitan reef-‐slope complex in the Guadalupe Mountains, west Texas. Spectacular stalactites and stalagmites in Carlsbad Caverns, New Mexico.

RkJQdWJsaXNoZXIy MjAxMjk=