--> Basin-Floor Fan Complexes in Cambrian Rift Basins of Kentucky, by J. A. Drahovzal; #90986 (1994).

Datapages, Inc.Print this page

Abstract: Basin-Floor Fan Complexes in Cambrian Rift Basins of Kentucky

James A. Drahovzal

Two east-west oriented, Cambrian rift basins extend across Kentucky. The Rough Creek Graben in western Kentucky is a north-dipping half graben bounded on the north by a major boundary fault. The graben is filled with up to 30,000 feet (9 km) of Cambrian synrift marine sediments. The Rome Trough in eastern Kentucky exhibits variable basin geometries and is separated from the Rough Creek Graben by the structurally inverted Precambrian East Continent Rift Basin. The Rome Trough contains up to 8,000 feet of similar Cambrian rift fill.

Limited seismic data available to the Kentucky Geological Survey provide evidence for turbiditic clastic sediments in the deep parts of both the Rough Creek Graben and the Rome Trough. A north-south oriented seismic line in the northwestern part of the Rough Creek Graben shows a basal, rift-fill sequence, characterized by bidirectional, downlapping, mounded reflector patterns, that pinches out on the south-rising basement. These seismic features are interpreted as basin-floor marine fan complexes whose sediment transport direction was likely longitudinal to the basin axis. Above the basal sequence boundary, lenticular sequences represented by low, broad, upwardly convex, downlapping, reflector patterns show evidence for both a southerly transport direction from the uplifted footwall a d a northerly direction from the north-dipping hanging wall. The southern source area was apparently dominantly responsible for the sediment that filled the upper part of the basin. In the deep part of the Rome Trough, similar basal reflector patterns are recognized on a single seismic line, also indicating a southerly sediment source.

The limited seismic data indicate that basin-floor fan complexes could be present throughout the two basins. Fan complexes often represent excellent reservoir facies, making them significant oil and gas exploration targets.

AAPG Search and Discovery Article #90986©1994 AAPG Annual Convention, Denver, Colorado, June 12-15, 1994