Along slope variations in mass failures and relationships to major plio-pleistocene morphological elements, SW Labrador Sea

Abstract

The slope along the SW Labrador Sea is a prospective exploration frontier with limited legacy data and geoscience knowledge. Newly acquired seismic reflection and multi-beam bathymetry data provide a better understanding of mass failure processes. A semi-continuous seismic section along the upper slope from Flemish Pass to north of Hamilton Spur shows an alternation of major morphological elements that includes canyons and failure corridors, inter-canyon ridges, ice-outlet trough mouth fans (TMFs), and sedimentary spurs. Preliminary geohazard investigation shows a wide variety of Plio-Pleistocene mass failure products including shallow detachment faults, head-scarps, creep folds, decollement surfaces, and a preponderance of mass transport deposits (MTDs) of various origins. Particularly noteworthy are two newly identified fans outboard the Hawke Saddle and Notre Dame Channel (believed to be TMFs constructed of mass wasted material), and a large shallow buried failure complex north of the Hamilton Spur, which contains many km-scale slide blocks dispersed over thousands of square kilometers.