Mesoscopic Fabric and Structural History of Brevard Zone and Adjacent Rocks, North Carolina
Structural fabric along and across the Brevard zone in North Carolina suggests that Phase I isoclinal folds overturned northwestward, mylonitic rocks along the zone, and Phase II open folds with northeast-trending axes all are compatible with a structural history involving compressive straining perpendicular to the length of the zone. The northeast-trending mineral lineation associated with mylonitic rocks occurs parallel to the direction of maximum extension within the mylonitic foliation surface, and no fabric elements observed require major northeast-southwest transport along the zone. The Brevard belt appears to have developed initially as an isoclinal synform, and reverse-slip displacement along the zone occurred as isoclinal folds overturned northwestward. Consistency of Phase I and Phase II structural fabric along and across the zone suggests that the belt does not mark a major structural discontinuity, and may indicate that the Blue Ridge thrust sheet does not root in the Brevard belt.