Occurrence of a Pseudophragmina (Proporocyclina) Zaragosensis Bank in Upper Wilcox (Lower Eocene), Pointe Coupee Parish, Louisiana

Lori L. Nunn, Rowdy C. Lemoine

Rock-forming buildups of larger foraminifera, though not unknown in Louisiana, are rare, and are less common in the Gulf Coast than in Eocene strata from the Tethyan and Caribbean regions. In strata from the upper Wilcox Group (lower Eocene) in Pointe Coupee Parish, Louisiana, we have identified a thin, very rich faunal deposit, or bank, made up almost exclusively of the tests of the larger foraminifera species, Pseudophragmina (Proporocyclina) zaragosensis. This is the first report of P. (P.) zaragosensis from the Louisiana Wilcox Group. The bank fauna colonized the sandy sea floor on the continental shelf, flourished briefly, and then gradually declined, probably in response to increasing water depth, caused either by compaction-induced subsidence and/or a local or regi nal rise in relative sea level. This bank indicates that, during late Wilcox deposition, warm, shallow continental-shelf conditions prevailed in this region.

AAPG Search and Discovery Article #91042©1987 GCAGS and GC-SEPM Section Meeting, San Antonio, Texas, October 28-31, 1987.