Parte I: Geología del área de Plomosas, Chihuahua

Luther W. Bridges II; Diego A. Cordoba

Authors

Luther W. Bridges II
Diego A. Cordoba

Keywords:

Ordovician, tectonism, Mina Plomosas, limestone, Jurassic

Abstract

The three pre-Carboniferous rock outcrops, which had not previously been recognized, are located in the Mina Plomosas-Placer de Guadalupe area, covering a total area of just under 6.5 km². Within the Plomosas Formation, named by Burrows in 1909, six units were mapped, ranging in age from the Ordovician to the Jurassic; the total thickness is approximately 2,440 meters. The lower 610 meters of the section are composed of Ordovician, Silurian, Devonian, Mississippian, and Pennsylvanian rocks, predominantly limestone, similar to some contemporary formations in western Texas. The section from 610 meters to 915 meters, between the Pennsylvanian and Late Jurassic, is mainly composed of siltstone and conglomerate, consisting of a Permian sequence 150 to 300 meters thick (Wolfcampian-Leonardian), overlain by layers of undetermined age. The Permian sequence includes a reef. The Late Jurassic section, 910 meters thick, is composed of shale, sandstone, and limestone.

The area lies to the north of the main Ouachita orientation; the Paleozoic tectonism was less intense than in the Marathon Uplift. Nevertheless, angular unconformities within the Permian sequence indicate Permian movements.

Laramide tectonism was extreme, with major thrusts towards the west. Two large sections are inverted. Crustal shortening of approximately 16 km can be demonstrated near the Mina Plomosas. The sericite and microspar (finely recrystallized limestone) of the Paleozoic and Jurassic rocks are probably the result of incipient metamorphism, mainly caused by Laramide deformation.

The Mina Plomosas is an important producer of lead and zinc. A small gold placer is located near Placer de Guadalupe. It is believed that all mineralization in the Placer de Guadalupe-Mina Plomosas area is of Tertiary age. The petroleum potential of Chihuahua has not yet been proven.

References

Aberdeen, E. J. (1940). Radiolarian fauna of the Caballos formation, Marathon basin, Texas. Journal of Paleontology, 14, 127-139.

Adams, J. A. S., & Weaver, C. E. (1958). Thorium to uranium ratios as indicators of sedimentary processes; example of concept of geochemical facies. American Association of Petroleum Geologists Bulletin, 42, 387-430.

Adkins, W. S. (1962). Reporte inédito mencionado por Keith Young.

Anderson, J. E. (1961). Comunicación oral, candidato al Doctorado, Dept. de Geología, Univ. Texas.

Arkell, W. J. (1956). Jurassic geology of the world. London: Oliver and Boyd Ltd.

Baker, C. L. (1927). Exploratory geology of a part of southwestern Trans-Pecos Texas. University of Texas Bulletin, 2745, 70.

Bateman, A. (1950). Economic mineral deposits (2nd ed.). New York: John Wiley and Son, Inc.

Berry, W. B. N. (1960). Graptolite faunas of the Marathon region, West Texas. University of Texas Bulletin, 6005, 1-44.

Bose, E. (1923). Vestiges of an ancient continent in northeast Mexico. American Journal of Science, 5th Series, 6, 127-136.

Bridges, L. W. (1958). Revised Cenozoic history of Rim Rock country, Trans-Pecos Texas. (Tesis de maestría). Univ. Texas.

Bridges, L. W., & DeFord, R. K. (1961). Pre-Carboniferous Paleozoic rocks in central Chihuahua, Mexico. American Association of Petroleum Geologists Bulletin, 45, 98-104.

Burckhardt, C. (1910). Nuevos datos sobre el Jurásico y el Cretácico en México. Instituto Geológico de México, Parergones, 3(5), 281-301.

Burrows, R. H. (1909). Geology of northern Mexico. Mining and Science Press, 99(2562), 290-294.

Burrows, R. H. (1910). Geology of northern Mexico. Sociedad Geológica Mexicana Boletín, 7, 85-103.

Bush, C. H. (1959). Comunicación oral, superintendente en Mina Plomosas.

Clabaugh, S. E. (1961). Comunicación oral, Dept. de Geología, Univ. Texas.

Comisión Intersecretarial Coordinadora del Levantamiento de la Carta Geográfica de la República Mexicana. (Primera edición). Hoja Chihuahua 13R-111, escala 1:500,000.

Cooper, G. A., et al. (1942). Correlation of the Devonian sedimentary formations of North America. Geological Society of America Bulletin, 53, 1729-1794.

Cotera, A. (1962). Petrology and petrography of the Tesnus Formation, Trans-Pecos, Texas. Disertación doctoral en preparación. Univ. Texas.

DeFord, R. K. (1958). Cretaceous platform and geosyncline, Culberson and Hudspeth Counties, Texas. Sociedad de Paleontólogos Económicos y Mineralogistas, Libreto-guía.

Bureau of Economic Geology. (1961-62). Comunicación oral. Austin, Texas.

Flower, R. (1958). Cambrian-Mississippian beds of southern New Mexico. Roswell Geological Society Guidebook, 11th Field Conference, 61-78.

Folk, R. L. (1954). The distinction between grain size and mineral composition in sedimentary rock nomenclature. Journal of Geology, 62, 344-359.

Folk, R. L. (1956). The role of texture and composition in sandstone classification. Journal of Sedimentary Petrology, 26, 166-171.

Folk, R. L. (1959). Practical classification of limestones. American Association of Petroleum Geologists Bulletin, 43, 1-38.

Folk, R. L. (1961a). Petrology of sedimentary rocks. Austin, Texas: Hemphill’s Book Store.

Folk, R. L. (1961b). Comunicación oral. Departamento de Geología, Universidad de Texas.

Frantzen, D. R. (1958). Oligocene folding in Rim Rock country, Trans-Pecos, Texas. (Tesis de maestría). Universidad de Texas.

Galley, J. E. (1958). Oil and geology in the Permian Basin of Texas and New Mexico. In Habitat of Oil: American Association of Petroleum Geologists Symposium, 395-446.

Gilluly, J. L. (1960). Comunicación oral. U.S. Geological Survey, Denver, Colorado.

Goddard, E. N., Trask, P. D., DeFord, R. K., Rove, O. N., Singewald, J. T., & Oderbeck, R. M. (1951). Rock-color chart (2nd ed.). Geological Society of America.

Holmes, A. (1960). A revised geological time-scale. Nature, 187, 27-28.

Humphrey, W. E. (1961). Comunicación oral. Vicepresidente, Foreign Exploration, Pan American Oil Co., New York, New York.

Imlay, R. W. (1943). Upper Jurassic ammonites from the Placer de Guadalupe district, Chihuahua, Mexico. Journal of Paleontology, 17, 527-543.

Indans, J. (1954). Eine Ammoniten fauna aus dem Untertithon der argentinischen Kordillere in Süd-Mendoza. Paleontographica, 105(Pt. A), 96-131.

Jones, T. S. (1953). Stratigraphy of the Permian basin of west Texas. West Texas Geological Society Publication, 57.

Kellum, L. B., Imlay, R. W., & Kane, W. G. (1936). Evolution of the Coahuila Peninsula, Mexico. Geological Society of America Bulletin, 47, 969-1008.

King, P. B. (1937). Geology of the Marathon region, Texas. U.S. Geological Survey Professional Paper 187.

King, P. B., & Flawn, P. T. (1953). Geology and mineral deposits of Precambrian rocks of the Van Horn area, Texas. University of Texas Bulletin 5301.

King, R. E., Dunbar, C. O., Cloud, P. E., Jr., & Miller, A. K. (1944). Geology and paleontology of the Permian area northwest of Las Delicias, southwestern Coahuila, Mexico. Geological Society of America Special Paper, 52.

King, R. E., & Adkins, W. S. (1946). Geology of a part of the lower Conchos valley, Chihuahua, Mexico. Geological Society of America Bulletin, 57, 275-294.

Kottlowski, F. E. (1961). Paleozoic and Mesozoic strata of south-central and southwestern New Mexico. Trabajo presentado en el Symposium de El Paso.

Krynine, P. D. (1946). The tourmaline group in sediments. Journal of Geology, 54, 65-87.

Krynine, P. D. (1948). The megascopic study and field classification of sedimentary rocks. Journal of Geology, 56, 130-165.

Larson, D. A. (1960-61). Comunicación oral. Departamento de Botánica, Universidad de Texas.

Lonsdale, J. T., Maxwell, R. A., Wilson, J. A., & Hazzard, R. T. (1955). Big Bend National Park, Texas. West Texas Geological Society, Libreto-guía.

Lovering, T. (1958). Temperatures and depth of formation of sulfide ore deposits at Gilman, Colorado. Economic Geology, 53, 689-707.

MacGillavry, H. J. (1961). Comunicación oral. Geologisch Instituut, Ámsterdam, Países Bajos.

Maubeuge, P. L., & Lambert, R. (1956). Sur quelques ammonites aaleniennes d’Argentine. Société Belge de Géologie, 620-624.

McBride, E. (1961-62). Comunicación oral. Departamento de Geología, Universidad de Texas.

Muehlberger, W. R. (1962). Comunicación oral. Departamento de Geología, Universidad de Texas.

Newell, N. D., et al. (1953). The Permian reef complex of the Guadalupe Mountains.

Bureau of Economic Geology. (1961-1962). Comunicación oral. Austin, Texas.