The Boquillas Formation of the Big Bend National Park, Texas, USA, a reference Cenomanian through Santonian (Upper Cretaceous) carbonate succession at the southern end of the Western Interior Seaway
Authors
Dee Ann Cooper
Texas Board of Professional Geoscientists, License No. 2238, Austin, TX 78757
Roger W Cooper
deceased
James B Stevens
PO Box 608, Terlingua, TX 79852
M S Stevens
PO Box 608, Terlingua, TX 79852
William A Cobban
deceased
Ireneusz Walaszczyk
Faculty of Geology, University of Warsaw, Al. Zwirki i Wigury 93, 02-089 Warszwa
Keywords:
Boquillas Formation, Upper Cretaceous, US Western Interior Seaway, Lithostratigraphy, Biostratigraphy, Paleoenvironment
Abstract
The upper lower Cenomanian through middle Santonian (Upper Cretaceous) of the Boquillas Formation in the Big Bend Region of Trans-Pecos Texas consists of a marine carbonate succession deposited at the southern end of the Western Interior Seaway. The Boquillas Formation, subdivided into the lower, c. 78 m thick limestone-shale Ernst Member, and the upper, c. 132 m thick limestone/chalk/marl San Vicente Member, was deposited in a shallow shelf open marine environment at the junction between the Western Interior Seaway and the western margins of the Tethys Basin. Biogeographically, the area was closely tied with the southern Western Interior Seaway. The richly fossiliferous upper Turonian, Coniacian and lower Santonian parts of the Boquillas Formation are particularly promising for multistratigraphic studies.
