FORAMINIFERAL POPULATIONS IN THE GRAYSON MARL

Abstract

Research Article| April 01, 1954 FORAMINIFERAL POPULATIONS IN THE GRAYSON MARL CLAUDE C ALBRITTON, JR.; CLAUDE C ALBRITTON, JR. DEPARTMENT OF GEOLOGY, SOUTHERN METHODIST UNIVERSITY, DALLAS, TEXAS Search for other works by this author on: GSW Google Scholar WILLIAM W SCHELL; WILLIAM W SCHELL DEPARTMENT OF GEOLOGY, SOUTHERN METHODIST UNIVERSITY, DALLAS, TEXAS Search for other works by this author on: GSW Google Scholar CHARLES S HILL; CHARLES S HILL DEPARTMENT OF GEOLOGY, SOUTHERN METHODIST UNIVERSITY, DALLAS, TEXAS Search for other works by this author on: GSW Google Scholar JOHN R PURYEAR JOHN R PURYEAR DEPARTMENT OF GEOLOGY, SOUTHERN METHODIST UNIVERSITY, DALLAS, TEXAS Search for other works by this author on: GSW Google Scholar GSA Bulletin (1954) 65 (4): 327–336. https://doi.org/10.1130/0016-7606(1954)65[327:FPITGM]2.0.CO;2 Article history received: 06 Apr 1953 first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation CLAUDE C ALBRITTON, WILLIAM W SCHELL, CHARLES S HILL, JOHN R PURYEAR; FORAMINIFERAL POPULATIONS IN THE GRAYSON MARL. GSA Bulletin 1954;; 65 (4): 327–336. doi: https://doi.org/10.1130/0016-7606(1954)65[327:FPITGM]2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract At Grayson Bluff in Denton County, Texas, the Grayson formation (Cretaceous) is 78 feet thick. It is divisible into four lithologic units: a lower marl, lower clay, upper marl, and upper clay. Each unit contains tests of Foraminifera in astonishing numbers that range from 1500 to more than 100,000/cm3.Twenty-two samples collected from as many horizons in the Grayson were analyzed according to their content of foraminiferal tests, classified by genera and families. The Lituolidae are the predominant benthonic family in the upper clay. In the lower clay the Bulminidae generally outnumber the combined Anomalinidae, Rotaliidae, and Lagenidae, while in both marl units the converse is the case.Lowman has shown that different families of Foraminifera predominate at different depths beneath the present Gulf of Mexico. Comparing the microfaunal facies of the Grayson with those described by him, it may be inferred that the lower two units of the Grayson were deposited in deepening waters, while the upper two were deposited in shoaling waters. This is compatible with the chronicle for the late Comanchean as known from studies of lithology, megafossils, and geologic structure. Similar analyses in other parts of the Coastal Plain might establish the order of reliability of foraminiferal populations as indicators of fluctuations in depth around the borders of the ancient Gulf of Mexico. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.