Metamorphic-Tectonic history of the Appalachians in North Carolina, South Carolina and Tennessee

Conference · Tue Jan 01 04:00:00 EST 1985 · Geol. Soc. Am., Abstr. Programs; (United States)

OSTI ID:6875859

Butler, J R; Kish, S A; Goldberg, S A; Fullagar, P D

This paper reviews the tectonic-metamorphic history of the Appalachians in NC, SC, and TN. Four proposed major upper crustal sutures include; (1) central blue Ridge (Fries-Hayesville faults), (2) Brevard zone, (3) central Piedmont (Kings Mountain-Lowndesville-Middleton shear zones) and (4) beneath the coastal Plain. A lower crustal suture beneath the Kings Mountain or eastern Charlotte belts has been proposed on geophysical evidence. Taconic thrusting in the Blue Ridge apparently placed an ocean-floor assemblage onto a continental margin sequence overlying Grenvillian crust. Alleghanian thrusting affected most of the exposed Appalachians; lower thrust sheets include Grenvillian rocks with Precambrian mineral age and rock fabric. Metamorphic maxima generally become progressively younger southeastward across the belt. Taconic metamorphism reached sillimanite grade and affected most of the Blue Ridge and Piedmont. Some Taconic (450-470Ma) structures show a large-scale symmetry, with NW-verging structures in the Blue Ridge and SE-verging structures in part of the eastern Slate belt. Acadian (about 400Ma) metamorphism and magmatism occurred in much of the Blue Ridge and Inner Piedmont; late Acadian (360-380Ma) shear zones are major features. Alleghanian penetrative deformation and amphibolite-grade metamorphism mainly occurred in the Raleigh and Kiokee belts, but foreland thrusting reached northwestward into continental crust beyond the earlier Paleozoic belts.

• Research Organization: Univ. of North Carolina, Chapel Hill (USA)
• OSTI ID: 6875859
• Report Number(s): CONF-8510489-
• Conference Information: Journal Name: Geol. Soc. Am., Abstr. Programs; (United States) Journal Volume: 17
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580100 -- Geology & Hydrology-- (-1989)
580201* -- Geophysics-- Seismology & Tectonics-- (1980-1989)
APPALACHIAN MOUNTAINS
FEDERAL REGION IV
GEOLOGIC FAULTS
GEOLOGIC FRACTURES
GEOLOGIC HISTORY
GEOLOGIC STRUCTURES
MAGMATISM
METAMORPHIC ROCKS
METAMORPHISM
MOUNTAINS
NORTH AMERICA
NORTH CAROLINA
ROCKS
SOUTH CAROLINA
TECTONICS
TENNESSEE
USA