Basal thrust contact of the accreted Carolina Slate belt volcanic arc, southern Appalachian piedmont
Fossil evidence indicates that the Carolina Slate belt, interpreted as a late Precambrian to early Paleozoic volcanic arc, is a terrane exotic to North America (Secor et al., 1983). Petrographic and isotopic evidence (Farrar, 1983) suggests that the Raleigh belt, located between the Western and Eastern Carolina Slate belts, is at least partly Grenville basement and has affinity to North America. West of the contact between the Carolina Slate belt and Raleigh belt terranes is an area underlain by two-mica schists with lenses and blocks of metamorphosed mafic and ultramafic rock, the Falls Lake melange (Horton et al. 1985). The authors believed this melange terrane represents the dismembered oceanic underpinnings of the Carolina Slate belt volcanic arc. East of and below the melange lies the Raleigh belt, a terrane characterized by quartzofeldspathic gneiss and schist with thin aluminum-rich graphitic horizons. The thrust zone in this structurally lower sheet is defined by a thinly ribboned gneiss, consisting of alternating biotite-rich and biotite-poor compositional layers no more than one cm wide. These layer have been folded by a series of plunging reclined folds and then refolded around subhorizontal plunging open folds. The thrust zone is defined by compositionally layered schist that grads upward into more homogeneous two-mica schist in the overlying Carolina Slate belt sheet. This thrust zone is then the basal contact or decollement between the allochthonous Carolina Slate belt and the autochthonous Raleigh belt; the Raleigh belt window is exposed by the latest generation of upright folds.
- Research Organization:
- North Carolina State Univ., Raleigh (USA)
- OSTI ID:
- 6322586
- Report Number(s):
- CONF-8510489-
- Journal Information:
- Geol. Soc. Am., Abstr. Programs; (United States), Vol. 17; Conference: 98. annual meeting of the Geological Society of America, Orlando, FL, USA, 28 Oct 1985
- Country of Publication:
- United States
- Language:
- English
Similar Records
Structural and lithologic relationships in the Raleigh metamorphic belt near Lake Gaston, Virginia and North Carolina
Falls Lake melange, a polydeformed accretionary complex in the North Carolina piedmont
Related Subjects
METAMORPHIC ROCKS
CHEMICAL COMPOSITION
PETROGENESIS
PETROGRAPHY
NORTH CAROLINA
SOUTH CAROLINA
GEOCHEMISTRY
GEOLOGIC FAULTS
GEOLOGIC HISTORY
ISOTOPE RATIO
VOLCANIC REGIONS
VOLCANISM
CHEMISTRY
FEDERAL REGION IV
GEOLOGIC FRACTURES
GEOLOGIC STRUCTURES
NORTH AMERICA
ROCKS
USA
580300* - Mineralogy
Petrology
& Rock Mechanics- (-1989)
580400 - Geochemistry- (-1989)