Crustal structure of the Appalachian Highlands in Tennessee

C. Prodehl; J. Schlittenhardt; S.W. Stewart

doi:10.1016/0040-1951(84)90170-7

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Crustal structure of the Appalachian Highlands in Tennessee

C. Prodehl·J. Schlittenhardt·S.W. Stewart

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Abstract

Crustal structure of the southern Appalachians and adjacent Interior Low Plateaus in Tennessee is derived from seismic-refraction measurements observed by the U.S. Geological Survey in 1965 along reversed lines, normal (NW-SE) and parallel (NE-SW) to the structure of the Appalachian Highlands' major geologic divisions. Its easternmost part is located approximately 80 km southwest of the westernmost part of the COCORP seismic-reflection traverse within the Blue Ridge province. The velocity-depth models derived for both observational directions consist of three crustal layers with surprisingly high velocities, being about 6.1-6.2 km/s in the upper crust down to 7-10 km depth, 6.7-6.8 km/s for the middle crust between about 17 and 34 km and varying from 7.1 to 7.4 km/s for the lower crust at about 40-47 km depth. The boundaries between the three crustal layers as well as the crust-mantle boundary are transition zones of up to 11 km thickness. Similar to old orogens in other parts of the earth, the main result is a thick crust, at places in excess of 50 km, with high average velocity and a broad crust-mantle transition zone.

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Tectonophysics Article

Source-reported bounding extent: 34.978847126844116° to 36.63028858771913° latitude; -90.31145359952295° to -81.6504228297176° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

C. Prodehl, J. Schlittenhardt, S.W. Stewart. 1984. Crustal structure of the Appalachian Highlands in Tennessee. https://doi.org/10.1016/0040-1951(84)90170-7

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