Eustatic and Far- Field Tectonic Control on the Distribution of a Carbonate Shoal: Example from the Upper Ordovician Upper Tanglewood Member of Lexington Limestone, Central Kentucky, USA

Abstract

Facies analysis was performed on each of five parasequences in upper Tanglewood Member of Lexington Limestone in central Kentucky and correlated laterally by integrating cyclicity and widespread deformed horizons in order to delineate depositional environments in the shoal complex. Facies analysis of each parasequence shows that the thickest and coarsest part of each parasequence corresponded to basement fault blocks, which have been shown to have experienced uplift during earlier Lexington Limestone deposition. The occurrence of thick, coarse facies on the same blocks suggests that the blocks continued to experience uplift into shallow water, where tides and waves redistributed sediments during upper Tanglewood deposition. Although eustacy apparently controlled parasequence cyclicity, Taconian far-field forces seem to have influenced facies distribution in each parasequence through synsedimentary basement growth-faulting.

AAPG Datapages/Search and Discovery Article #90218 © 2015 Eastern Section Meeting, Indianapolis, Indiana, September 20-22, 2015