Stratigraphy, sedimentology, and structural geology of gypsum caves in east central New Mexico
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Hundreds of solution caves have developed in evaporites and carbonates of the Permian San Andres Formation where it crops out between Vaughn and Roswell, New Mexico, USA. Several of the caves are over 3.2 km (2 miles) in length, and the deepest has a vertical extent of over 120 m (400 feet). These gypsum caves afford an extraordinary opportunity to examine the evaporite rocks in which they are developed. We have examined interbedded gypsum and dolostone strata exposed in the walls of 11 of these caves, and show stratigraphic sections on two geologic cross sections.
Gypsum textures exposed in the caves include massive, nodular, and laminar types. While we refer to them as “gypsum caves,” gypsum is not the only lithology exposed. Some cave passages and rooms are developed in thick dolostone units intercalated with or overlain by gypsum beds. Correlation of beds exposed in two or more caves has allowed us to infer the local geologic structure.
The sedimentary sequence penetrated by a cave exerts a profound effect on the geometry and passage cross-section of the cave. Many cave passages have gypsum walls and a dolostone or limestone floor. Although many of the cave passages flood completely during major storm events, the stairstep profile of most of the caves is indicative of speleogenesis that has occurred predominantly within the vadose zone.
KeywordsDolostone Gypsum Anhydrite Evaporite Stromatolite
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- BLATT, HARVEY, MIDDLETON, G. and MURRAY, R., 1980, Origin of Sedimentary Rocks. Prentice-Hall, 2nd Ed., 782 p.Google Scholar
- BOGGS, S. JR., 1992, Petrology of Sedimentary Rocks. Macmillan Publishers, p. 566–567.Google Scholar
- DUCHENE, HARVEY, 1987, Some Comments Regarding the Geology of El Burro Grande, Southwestern Region, National Speleological Society:GYPKAP Report, v. 1, p. 21–23.Google Scholar
- DUCHENE, HARVEY and BELSKI, D.S., 1992, The San Andres Formation of the Pecos Slope Gypsum, Southeastern New Mexico, 1988–1991, Southwestern Region, National Speleological Society:GYPKAP Report, v. 2, p. 12–15.Google Scholar
- FORBES, J., NANCE, R., and POLYAK, V., 1996, Stratigraphy and Sedimentology of GYPKAP Caves,in Eaton, J., ed., Southwestern Region, National Speleological Society:GYPKAP Report, v. 3, p. 54–68.Google Scholar
- GUSTAVSON, T.C., HOVORKA, S.D., and DUTTON, A.R., 1994, Origin of Satin Spar Veins in Evaporite Basins:Journal of Sedimentary Research, v. A64, p. 88–94.Google Scholar
- KELLEY, V.C., 1971, Geology of the Pecos Country, Southeastern New Mexico,New Mexico Bureau of Mines and Mineral Resources Memoir, v. 24, 75 p.Google Scholar
- MAIKLEM, W.R., BEBOLT, D.G., and GLAISTER, R.P., 1969, Classification of anhydrite-A Practical Approach:Canadian Petroleum Geology Bulletin, v. 17, p. 194–233.Google Scholar
- MURRAY, R.C., 1964, Origin and Diagenesis of Gypsum and Anhydrite:Journal of Sedimentary Petrology, v. 34, p. 512–523.Google Scholar
- WARREN, J.K., 1989, Evaporite Sedimentology. Prentice-Hall, 285 p.Google Scholar
- WEBER, R.H. and KOTTLOWSKI, F.E., 1959, Gypsum Resources of New Mexico:New Mexico Bureau of Mines and Mineral Resources Bulletin, v. 68, 68p.Google Scholar