Geology topics

Kenneth J. Englund

Publications and source records attributed to Kenneth J. Englund.

3 recordsLinked to original sources

USGS1990

Late Paleozoic depositional trends in the central Appalachian Basin

Trends in the regional extent, stratigraphical distribution, and character of upper Paleozoic terrestrial rocks in the central Appalachian basin were influenced by depositional events associated with basin evolution. Most of these rocks originated as siliciclastic detritus eroded from tectonic highlands that were elevated by plate collision along the southeastern margin of the basin. Terrestrial sediments, indicated by northwestward-prograding delta lobes and fluvial systems, were deposited in a slowly subsiding foreland basin. Concurrently, marine deposition encroached from the northwest in a shallow epicontinental sea that covered an unstable cratonic shelf. Terrestrial progradation extended northwestward during periods of high rainfall and sufficient subsidence to accommodate a high influx of clastic sediments. Conversely, marine incursions extended farthest southeastward during periods of diminishing rainfall and low clastic influx. As the Appalachian basin evolved, terrestrial deposition gradually shifted northwestward and occupied the entire basin by Early Permian time. In addition, the standline or wedgeout of terrestrial coal-bearing deposits rotated from N 30°E in Early Mississippian time to N 65° E in Early Pennsylvanian time. -from Authors

Alabama, Georgia, Kentucky, Maryland, Ohio, Pennsy↗

USGS1981

Geologic map of the Beaver Creek Wilderness, McCreary County, Kentucky

The Beaver Creek Wilderness comprises approximately 4,800 acres and is principally within the cliffline bordering the Beaver Creek drainage basin in McCreary County, southeastern Kentucky. It is part of the Beaver Creek Cooperative Wildlife management Area in the Daniel Boone National Forest, which is managed by the U.S. Forest Service and the Kentucky Department of Fish and Wildlife Resources. The wilderness is about 11 mi southeast of Burnside, Ky., and is accessible from thr north and south via U.S. Route 27 and Forest Service Road 50, at its northwest border (fig. 1). From the east the area can be reached via State Route 90 and Forest Service Road 46, at the eastern end of the wilderness. The interiors is accessible by foot along an abandoned Forest Service road and by several primitive trails that extend along the major streams. The Beaver Creek Wilderness is centrally located at the western edge of the Appalachian coal regions and is within the highly dissected Cumberland Plateau section of the Appalachian Plateaus physiographic province (fig. 2). It is drained by Beaver Creek and tributaries, which flow northeastward into Cumberland Lake, a reservoir on the Cumberland River about 1 mi north of the wilderness. Altitudes range from about 730 ft on the lower part of Beaver Creek to about 1,200 ft at its headwaters.

Kentucky↗

USGS1974

Sandstone distribution patterns in the Pocahontas Formation of southwest Virginia and southern West Virginia

The Pocahontas Formation is a clastic wedge of sandstone, siltstone, shale, coal, and underclay that is transitional between underlying marine strata of Mississippian age and overlying continental beds of Pennsylvanian age. It attains a maximum thickness of 750 ft. at the southeastern edge of the Appalachian coal field and thins northwestward by the tonguing out of lower beds and by the truncation of upper beds at an overlying unconformity. Sandstone, which composes about 70 percent of the formation, occurs in lenticular bodies that have two distinct distribution patterns—lobate and linear—of contrasting orientation and composition. The lobate bodies are elongate to the northwest and contain sandstone having a quartz content of about 50 to 65 percent. Within a lobe, thickness lines show a northwestward bifurcating pattern similar to the pattern of channels in an alluvial distributary system of a modern delta. Laterally, lobate bodies merge to form northwestward-thinning sandstone wedges as much as 300 ft. thick. The linear pattern is shown by 3- to 8-mi.-wide sandstone lenses that extend north-northeast for about 45 mi. They are near the distal ends of the lobate sandstone and consist of 0 to 140 ft. of relatively pure quartzose sandstone. The well-washed character and orientation of the linear bodies, normal to the lobate bodies, indicate a barrier-bar origin. These sediment distribution patterns show that the Pocahontas Formation was deposited mainly in deltaic complexes built out from the southeast during marine regression to the northwest. Brief periods of transgression and stable shoreline conditions are recorded by tongues of marine strata and by the barrier bars.

Virginia, West Virginia↗