Geology of the Meherrin, Virginia area: tracing formations across the staurolite isograd from the Carolina slate belt into the Charlotte belt

Detailed mapping along the northern terminus of the Carolina slate belt in the area of Meherrin, Virginia extends the previously known limits of the Hyco and Aaron Formations from the greenschist metamorphic facies Carolina slate belt northward across a staurolite isograd into the amphibolite metamorphic facies Charlotte belt. The Hyco formation is subdivided into four facies: a crystal tuff facies, a felsic tuff facies, an interlayered mafic and felsic volcanic facies, and a feldspathic wacke facies. The Aaron formation is dominantly a pelitic schist. Three deformational events are identified. F₁ produced the initial foliation. F₂ produced the dominant penetatrive foliation, isoclinally folding the earlier foliation. F₃ produced a crenulation cleavage. The Hyco and Aaron formations are folded into a tight, steeply southeastward dipping, and slightly refolded syncline. The undifferentiated Charlotte belt rocks form a doublely plunging antiform of refolded F₂ folds. The syncline formed by the Hyco and Aaron formations is northeastward along strike from the type location of the Virgilina synclinorium. Glover and Sinha (1973) attribute the formation of the Virgilina synclinorium to a late Precambrian and (or) early Cambrian orogenic event, and Glover and others (1983) attribute late folding and metamorphism to the Taconic orogeny. F₁ is attributed to the Virgilina deformation. F₂ and F₃ are attributed to the Taconic and/or Acadian orogenies.