Dunite Pod

Anhydrous dunite pod
Anhydrous dunite pods like the outcrop above occur throughout the Ashe Metamorphic Suite.

The nature and origin of ultramafic rocks, especially dunite pods, in the Blue Ridge Belt are now fairly well understood. The ultramafic and associated mafic (dark) rocks represent dismembered pieces of the lower crust and mantle (called ophiolites) emplaced into the crust during mountain building.

Useful References

Swanson, S. E., and Raymond, L. A., 2010, Petrogenesis of chromite in metaultramafic rocks of the Spruce Pine Area, North Carolina, Southeastern Geology, v. 47, no. 3, p. 147-172.

Peterson, V. Ryan, J., Yurkovich, S., Burr, J., Kruse, S., and 1997-2001 REU Participants, 2006, The Petrogenesis and tectonic implications of Blue Ridge mafic-ultramafic rocks: The Buck Creek and Carroll Knob complexes, and rocks of the Addie-Willits region: in Labotka, T.C. and Hatcher, R.D., Jr., eds., Geological Society of America 2006 Southeastern Section Meeting Field Trip Guidebook: University of Tennessee Department of Earth and Planetary Sciences, Knoxville, TN, p. 101-127.

Swanson, S.E., Raymond, L.A., Warner, R.D., Ryan, J.G., Yurkovich, S.P., and Peterson, V.L., 2005, Petrotectonics of mafic and ultrmafic rocks in Blue Ridge Terranes of western North Carolina and northern Georgia: in Hatcher, R.D., Jr. and Merschat, A.J., eds., Blue Ridge Geology Geotraverse East of the Great Smoky Mountains National Park, Western North Carolina: Carolina Geological Society Annual Field Trip Guidebook, p. 73-90.

Loren A. Raymond, Samuel E. Swanson, Anthony B. Love and James F. Allan, Cr-spinel compositions, metadunite petrology, and the petrotectonic history of Blue Ridge ophiolites, Southern Appalachian Orogen, USA Geological Society, London, Special Publications 2003, v. 218, p. 253-278

McSween, H. Y., Jr., and Hatcher, R. D., Jr., 1985, Ophiolites(?) of the southern Appalachian Blue Ridge, in N. E.
Woodward, ed., Field Trips in the Southern Appalachians, Univ. of Tennessee Department of Geolgocial
 Sciences, Studies in Geology, v. 9, p. 144-170.

Abbott, R. N., Jr. and Raymond, L. A., 1984, The Ashe Metamorphic Suite, northwest North Carolina: Metamorphism
and observation on geologic history: American Journal of Science, v. 284, p. 350-375.