Paleochannels through the Fire Clay coal
Numerous paleochannels cut through the Fire Clay coal in parts of Leslie, Letcher, and Perry Counties in the Eastern Kentucky Coal Field. Channels are 100 to 1,500 feet wide and as much as 50 feet thick. Channel fills vary from thick sandstone to mixed shale and sandstone to shale. Several paleoslumps have been noted in channels (Greb and Weisenfluh, 1996). Channels are curvilinear to straight, but follow a general east-west to northwest-southeast primary trend; secondary trends follow a more northeast-southwest orientation. Several oblique intersections in apparent channel trends may define subtle fault blocks (Greb and others, 1999a, c). Known channels can be traced across a distance of at least 24 miles.