麻豆传媒

B. Sc. Honours Thesis

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The conglomerates of northern Cape George represent a tectonic block, thrusted from the north during the Carboniferous. Previous provenance studies of the Cape George alluvial fan sediments have not been done in great detail so that a probable source of the sediments had not be determined. During a provenance study of the Cape George sediments the following questions were asked, concerning the reliability of the southeasterly paleocurrent direction:

1. Has the Cape George thrust block received any rotation?
2. Are the strata of Cape George representative of only a part of an alluvial fan or is the entire fan contained in Cape George?
3. Have enough paleocurrent vectors been measured so that a reliable average paleocurrent direction can be determined?

During the Middle to Late Devonian, uplift in northern Nova Scotia and Cape Breton Island resulted in extensive unroofing and weathering of deeply buried metaquartzites and granites. During the Early Carboniferous extensive block faulting resulted in the formation of deep intermontane basins in which thick accumulations of sediment occurred. The coarse-grained, poorly sorted orthoconglomerates of northern Cape George were deposited by alluvial fans during the Early Carboniferous and accumulated to a thickness of greater than 1 km. Southward thrusting of the Cape George conglomerates, with minor amounts of rotation, occurred during the Carboniferous.

An analysis of structural and sedimentological data, together with a study of the clast lithologies in the conglomerates, suggests that the Cape George sediments were probably derived from a northerly source and that since the Early Carboniferous most of the original rocks in the source area have been eroded or buried.

Keywords:
Pages: 98
Supervisor: Paul Schenk

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