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Research about Kentucky, Virginia

Source-linked reports with geographic coverage including Kentucky, Virginia.

7 recordsLinked to original sources

Fluvial sediment study of Fishtrap and Dewey Lakes drainage basins, Kentucky-Virginia

Fourteen drainage basins above Fishtrap and Dewey Lakes in the Levisa Fork and Johns Creek drainage basins of eastern Kentucky and southwestern Virginia were studied to determine sedimentation rates and origin of sediment entering the two lakes. The basins ranged in size from 1.68 to 297 square miles. Sediment yields ranged from 2,890 to 21,000 tons per square mile where surface-mining techniques predominated, and from 732 to 3 ,470 tons per square mile where underground mining methods predominated. Yields, in terms of tons per acre-foot of runoff, ranged from 2.2 to 15 for surface-mined areas, and from 0.5 to 2.7 for underground-mined areas. Water and sediment discharges from direct runoff during storms were compared for selected surface-mined and underground-mined areas. Data points of two extensively surface-mined areas, one from the current project and one from a previous project in Beaver Creek basin, McCreary County, Kentucky, grouped similarly in magnitude and by season. Disturbed areas from mining activities determined from aerial photographs reached 17 percent in one study area where extensive surface mining was being practiced. For most areas where underground mining was practiced, percentage disturbed area was almost negligible. Trap efficiency of Fishtrap Lake was 89 percent, and was 62 percent for Dewey Lake. Average annual deposition rates were 464 and 146 acre-feet for Fishtrap and Dewey Lakes, respectively. The chemical quality of water in the Levisa Fork basin has been altered by man 's activities.

Kentucky, Virginia

Petrographic differentiation of depositional environments of sandstones of the Pennsylvanian Breathitt Formation, northeastern Kentucky and southwestern West Virginia

Petrographic properties of sandstone samples from the lower and middle Pennsylvanian Breathitt Formation in northeastern Kentucky and southwestern West Virginia were utilized to classify their environments of deposition. Simultaneous consideration of mineral composition, grain size, and sorting of the sandstones by using stepwise multiple discriminant-function analysis has permitted differentiation between alluvial-plain and delta-plain sandstones. Stepwise multiple discriminant-function analysis of the sandstone samples- was performed in two parts. The first analysis assigned the sandstones of all grain-size classes to one of three environments of deposition: (1) alluvial plain, (2) upper delta plain, and (3) lower delta plain. The second analysis classed the sandstones by grain size and subdivided each grain-size class into these environmental groups. Discriminant analyses of sandstones of all grain-size classes led to correct assignment of depositional environment to 76 percent of the samples. Analyses of the sandstones classed by grain size led to correct classification of 67 percent of the medium-grained sandstones, 83 percent of the fine-grained sandstones, and 91 percent of the very fine grained sandstones. The discriminantfunction method was adopted to classify the depositional environment and stratigraphic position of test sandstone samples. Analyses of fine-grained and very fine grained sandstones resulted in correct classification of 84 percent of the test samples to their depositional setting and stratigraphic position. The best discrimination is offered by analyses of fine-grained sandstones, which resulted in correct classification of 88 percent of the samples. Thus, this statistical method can be adopted as a powerful tool for exploration programs that concern delineation of genetically similar sandstones.

Kentucky, Virginia