The Gold Hill shear zone is a first-order structure in the peri-Gondwanan Carolina Zone of the southern Appalahcians; it separates the Carolina terrane from the Charlotte terrane in North Carolina. Traditionally, the shear zone has been considered to be a Devonian dextral strike slip zone based on circumstantial evidence. However, Late Ordovician regional folds in the Carolina terrane define an oblique, en echelon array that is truncated by the shear zone. We hypothesize that the Gold Hill shear zone was originally a Late Ordovician, sinistral transpressive zone. Our studies to date support this hypothesis.
The Piedmont Zone is axially located between Laurentian crust and the exotic Carolina Zone. Situated as such, the zone offers an opportunity to investigate the timing and nature of Laurentian-Carolinian interactions. The age, style and timing of deformation, and crustal affinity of the Piedmont Zone are not well known. Recently, we have identified an Early Cambrian high-grade tectonothermal event in the Smith River Allochthon, in the western portion of the zone. This event strongly suggests that rocks of the allochthon are exotic to Laurentia, and likely of peri-Gondwanan origin. The allochthon lies structurally above native Laurentian rocks without intervening oceanic or arc rocks; this geometry of crustal elements is unique in the Appalahcian orogen.
We have identified a suite of early Laramide structures within the Mesa Verde Group along the west flank of the Nacimiento Uplift. these structures include normal and reverse faults, upright folds, and clastic dikes. our objectives are to define the geometry and kinematics of these structures and determine their interrealtionship with the main phase of uplift inthe adjacent Naciemiento Range. We have undertaken a pilot vitrinite reflectance study with Mike Underwood at the University of Missouri, that reveals a thermal anomaly along one of the reverse faults.
Hibbard, J., Tracy, R., and Henika, W.,2003 (accepted) The Smith River Allochthon: A southern Appalachian peri-Gondwanan terrane emplaced directly on Laurentia? Geology.
Hibbard, J., Stoddard, S., Secor, D.T., Jr., and Dennis, A., 2002, The Carolina Zone: Overview of Neoproterozoic to early Paleozoic peri-Gondwanan terranes along the eastern flank of the southern Appalachians, Earth-Science Reviews, 57, p. 299-339.
Hibbard, J., 2000, Docking Carolina: Mid Paleozoic accretion in the southern Appalachians, Geology, v. 28., p. 127-130.
Vines, J., Hibbard, J., and Shell, G., 1998., Structural geology of the High Rock granite in the hangingwall of the Hyco shear zone, Southeastern Geology, p. 163-176..
Wortman, G., Samson, S., and Hibbard, J., 1998, Precise U-Pb zircon timing constraints on the kinematic development of the Hyco shear zone: implications for the central piedmont shear zone, southern Appalachian orogen, American Journal of Science, v. 298, p. 108-130.
Wortman, G., Samson, S., and Hibbard, J., 1996, Discrimination of the Milton belt and Carolina terrane in the southern Appalachians: a Nd isotopic approach, Journal of Geology 104, p. 239-247.
Hibbard, J. and Samson, S., 1995, Orogenesis exotic to the Iapetan cycle in the southern Appalachians, in Hibbard, J.P., van Staal, C.R., and Cawood, P.A., eds., Current Perspectives in the Appalachian-Caledonian Orogen, Geological Association of Canada Special Paper 41, p 191-205.
Samson, S., Hibbard, J., and Wortman, G., 1995, Nd isotopic evidence for juvenile crust in the Carolina terrane, southern Appalachians, Contributions to Mineralogy and Petrology 121, 171-184.
Hibbard, J., St. Julien, P., and Triecienski, W. Jr., 1995, Intensely deformed interior parts of the Humber Zone Miogeocline, in Williams, H. (ed.), The Canadian Appalachian Region, Geological Society of America DNAG volume F-1, 114-139.
Hibbard, J., 1994, Kinematics of Acadian deformation in the northern and Newfoundland Appalachians, Journal of Geology, p. 215-228.
Hibbard, J. & Hall, S., 1993, Early Acadian sinistral shear in north-central Maine, to Journal Geological Society, London, 150, 815-818.
Hibbard, J., Laughland, M., Kang, S., & Karig, D., 1993, Thermal imprint of spreading ridge subduction on the upper structural levels of an accretionary prism; southwest Japan, in Underwood, M. (ed.), Thermal Maturity of an Accretionary Prism, the Shimanto Belt of Southwest Japan, Geological Society America, Special Paper 273, 83-101.
Hibbard, J., Karig, D., and Taira, A., 1992, Oligocene-Miocene geology of the Shimanto accretionary prism, Murotomisaki, southwest Japan, The Island Arc, 1, 133-147.
Stewart, K. and Hibbard, J., 1992, Late Cretaceous thrust faulting at the eastern edge of the San Juan Basin, New Mexico, San Juan Basin IV: New Mexico Geological Society Guidebook, 43, 7-9.
Hibbard, J. and Karig, D., 1990, An alternative model for the early Miocene evolution of the southwest Japan plate margin, Geology, 18, 170-174.
Hibbard, J. and Karig, D., 1990, Structural and magmatic responses to spreading ridge subduction; and example from southwest Japan, Tectonics, 9, 207-230.
Hibbard, J., 1984, Provisional geological map for the Island of Newfoundland, scale 1:1,000,000, Nfld. Dept Mines & Energy map 84-103.
Hibbard, J., 1983, Geology of the Baie Verte Peninsula, Newfoundland, Nfld. Dept. Mines & Energy Memoir 2, 279 p.
Hibbard, J., & Williams, H., 1979, Regional Setting the Dunnage Melange, north-central Newfoundland, American Journal of Science, 279, 993-1021.
Standard, I., Hibbard, J., Miller, B., Hames, W., and Lavalee, S., 2002, Kinematics and timing of the Gold Hill shear zone, south-central North Carolina: Implications for sinistral transpression in the southern Appalachians. GSA Abstracts with Programs, v. 34, n. 6, p. 439
Hibbard, J., van Staal, C., Rankin, D., and Williams, H., 2001, Preliminary compilation of the new lithotectonic map of the Appalachian Orogen. GSA Abstracts with Programs, v. 33, n. 6, p. A-81.
Tracy, R., Hibbard, J., and Henika, W., 2001, Implications of a Cambrian (530 Ma) tectonothermal event in the Smith River allochthon, southern Virginia. GSA Abstracts with Programs, v. 33, n. 6, p. A-262.
van Staal, C. and Hibbard, J., 2000, Tectonic history of the Appalachian margin of Laurentia after break-up of Rodinia: International Geological Congress, Rio de Janeiro, Brazil.
Hibbard, J., Stoddard, E., Secor, D., and Dennis, A., 2000, The Carolina realm: Overview of exotic terranes along the eastern flank of the southern Appalachians, Geological Society of America Abstracts with Programs, v. 32, n. 2, p. 26.
Hibbard, J., Rankin, D., van Staal, C., and Williams, H., 1999, Preliminary framework for the new lithotectonic map of the Appalachian Orogen, Geological Society of America Abstracts with Programs, v. 31, n. 3, p. 20 and v. 31, n. 2, p. 23-24.
Hibbard, J., Vines, J., Bradley, P., and Shell, G., 1997, Geometry and implications of a regional ductile thrust ramp system in the southern Appalachians, Geological Society of America Abstracts with Programs, v. 29, n. 6, p. 230-231.
Hibbard, J., 1997, Is the central Piedmont suture a suture?, Geological Society of America Abstracts with Programs, 29, no. 3, p. 24.
Ozdogan, M., Cattanach, B., Bradley, P., and Hibbard, J., 1997, Preliminary results of detailed mapping in the Milton terrane, south-central Virginia,Geological Society of America Abstracts with Programs 29, no. 3, p. 62.