[First Hit]

Datapages, Inc.Print this page

AITKEN, JOHN F. and STEPHEN S. FLINT, University of Liverpool, U.K., L69 3BX

ABSTRACT: High Frequency Previous HitSequencesNext Hit within the Pennsylvanian, Breathitt Group, Appalachian Basin, Eastern Kentucky

The Pennsylvanian, Breathitt Group in eastern Kentucky is well exposed in large highway cuts which provide depositional dip and strike sections of up to 125 km and 100 km respectively. Parasequences and parasequence sets, with notable exceptions, are generally not identifiable. Nonetheless, it is possible to identify systems tracts on the basis of sequential position, facies associations and systematic changes in architectural style and sediment body geometries. The studied portion of the Breathitt Group represents three superimposed 3rd order composite Previous HitsequencesNext Hit, each comprising stacked aggradational, progradational or retrogradational 4th order Previous HitsequencesNext Hit. Stacking patterns indicate that the 4th order Previous HitsequencesNext Hit occur in lowstand, transgressive and highstand Previous HitsequenceNext Hit sets related to t e development of the 3rd order Previous HitsequencesNext Hit.

In the lowstand Previous HitsequenceNext Hit set, incision associated with successive 4th order Previous HitsequenceNext Hit boundaries has commonly removed all the highstand and transgressive systems tracts of the underlying Previous HitsequencesNext Hit, such that succeeding 4th order incised valleys are amalgamated. Within the transgressive Previous HitsequenceNext Hit set, incision is at a minimum and incised valleys tend to stack discretely with the maximum amount of finegrained transgressive and highstand deposits between them. Highstand Previous HitsequenceNext Hit sets are transitional in net: gross ratio between the lowstand and transgressive Previous HitsequenceNext Hit sets.

Volumetrically, the majority of preserved sediment is represented by incised valley fills which offer the best potential reservoir rocks. The proliferation of individual sandstone beds within 4th order Previous HitsequencesNext Hit offers multiple stacked reservoir targets. The lowstand Previous HitsequenceTop set is the most favourable, having the best reservoir potential owing to the greatest proportion of sandstone.

AAPG Search and Discovery Article #90987©1993 AAPG Annual Convention, New Orleans, Louisiana, April 25-28, 1993.