STRATIGRAPHY AND STRUCTURAL GEOLOGY OF THE ORDOVICIAN VOLCANO-SEDIMENTARY ROCKS IN THE MARY MARCH BROOK AREA

The Mary March Brook area was previously considered to be underlain by rocks of the Lundberg Hill and Sandy Lake formations of the Buchans–Roberts Arm belt. Detailed outcrop investigations and analyses of the geomagnetic anomalies suggest that this interpretation needs to be revised and the area is here subdivided into the Harry's River ophiolite complex, Mary March Brook and Seal Pond formations (Buchans–Roberts Arm belt), and the Red Indian Lake group. The boundaries between some of these tectonostratigraphic units are interpreted to be thrusts that were subsequently folded by F2 folds. The revised stratigraphy and the recognition of regional thrusts and folds have important implications for mineral exploration in the study area.

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