Geologic map of the Great Smoky Mountains National Park region, Tennessee and North Carolina

Abstract

The eastern part of the Tennessee Valley of the Valley and Ridge is underlain by Ordovician limestone and thin siliciclastic rocks interbedded with limestone. The sandy and shaly beds underlie linear hills with relief ranging from about 900 ft to 1400 ft (274 to 427 m) on Bays Mountain. The dominant surficial deposits are broad alluvial flood plains, fluvial terraces, and local areas of residuum. Sinkholes also are common. Surficial Deposits preserved in "The Glades", where no modern drainage exists. The earlier north-flowing drainage was captured by Dunn Creek, which flows west to Gatlinburg, leaving "the Glades" as an abandoned "dry" valley. On terraces near Pigeon Forge, TN, cobbles and pebbles of coarse metasandstone derived from the highlands were transported a distance of more than 7 miles (12 km). Upper level terraces (QTt) are cut into bedrock as much as 200 ft (61 m) above current stream levels. Much of the unconsolidated deposits once lying on the bedrock have been eroded away, leaving a few remnant boulders and cobbles on the flat area. Upper level terraces occur along the Tuckasegee River between Ela and Bryson City, NC, along Little River in Tuckaleechee Cove, and along West Prong of the Little Pigeon River and Little Pigeon River, between Pigeon Forge and Sevierville, TN.

Reinterpretation of the Greenbrier fault, Great Smoky Mountains: New petrofabric constraints and implications for southern Appalachian tectonics

“…Strata in the Greenbrier footwall are primarily Roaring Fork and Pigeon metasiltstone of the Snowbird Group. Metcalf Phyllite (the tectonized equivalent of the Pigeon metasiltstone; Clemons and Moecher, 2008) is exposed in a belt west of the study area (Hadley and Goldsmith, 1963;Southworth et al, 2005b). It is bounded below by the Great Smoky or Dunn Creek faults, and is overlain by Great Smoky Group units above the Greenbrier fault (i.e., the same structural relationship as in the present study area).…”

“…These components were metamorphosed to varying degrees during Ordovician (Taconian) tectonism that remains poorly constrained. Mesoproterozoic and Early Paleozoic structures were overprinted or possibly reactivated by Late F o r e la n d F o ld -a n d -T h r u s t B e lt (Southworth et al, 2005b). The Snowbird Group (basal Ocoee) is generally fi ne-to medium-grained feldspathic metasiltstone, metasandstone, slate, and phyllite, with thin basal metaconglomerate.…”

Lecanora anakeestiicola(Lecanorales): an unusual new fruticose species from Great Smoky Mountains National Park in eastern North America

“…Heavy-metal rich rocks such as those found in the Anakeesta Formation are otherwise very uncommon in the southern Appalachians. Instead, heavy-metal deficient granites, schists and sandstones dominate the vast majority of the region (Southworth et al 2012).…”

Scientific visualization of landscapes and landforms

“…The location and characteristics of the shallow landslides have been traditionally mapped using aerial imagery and selected field traverses (Southworth et al, 2005). Recent multiple return LiDAR mapping of western North Carolina provides the opportunity to identify previously unmapped or recent debris flows and derive additional information about the structure and properties of the ones previously identified.…”

“…Visualization techniques have been essential for the assessment of information that can be derived from the LiDAR-based surfaces and to guide the analysis of spatial relationship between geology, vegetation and landslide locations. A color map representing geology draped over the bare Earth DEM displayed in 3D perspective provided insight into the relation between geology (Southworth et al, 2005) and landforms geometry in the Bradley Fork watershed (Fig. 10).…”