Upper Cretaceous Bituminous Coal Deposits of the Olmos Formation, Maverick County, Texas
Robert W. Hook, Peter D. Warwick, John R. SanFilipo, 2011. "Upper Cretaceous Bituminous Coal Deposits of the Olmos Formation, Maverick County, Texas", Geologic Assessment of Coal in the Gulf of Mexico Coastal Plain, Peter D. Warwick, Alexander K. Karlsen, Matthew Merrill, Brett J. Valentine
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Near the Barents Sea coast in northern Timan, turbidites of probable Neoproterozoic age are intruded by pre-tectonic dolerites and a major suite of gabbros, granites and syenites (some nepheline bearing). Zircon ion microprobe dating of three plutons has yielded well-defined ages of 613–617 Ma. This alkaline igneous activity apparently represents a final phase of Vendian extensional magmatism prior to Timanian Orogeny. Previous work on late to post-orogenic calc-alkaline granites in the basement beneath the Pechora Basin, three hundred kilometres towards the SE, has yielded c. 550–560 Ma single zircon Pb-evaporation ages. These compositionally different intrusive suites are inferred to constrain the main phase of Timanian Orogeny to c. 610–560 Ma.
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Geologic Assessment of Coal in the Gulf of Mexico Coastal Plain
This publication is the fifth in a searies of reports by the U.S. Geological Survey on the assessment of the quantity and quality of the nation's coal deposits that potentially can be mined during the next few decades. For eight years (1995-2003), geologic, geochemical, and resource information was collected and compiled for the five major coal-producing regions of the United States. This volume contains the assessment results for the Gulf of Mexico Coastal Plain region. The contents of this volume were compiled mainly during the 8-year period mentioned above. However, every effort has been made to update the references and text to incorporate new work that has been completed since the original compilation period.