Charles D. Hollister, Roger D. Flood, David A. Johnson, Peter Lonsdale, John B. Southard; Abyssal Furrows and Hyperbolic Echo Traces on the Bahama Outer Ridge. Geology ; 2 (8): 395–400. doi: https://doi.org/10.1130/0091-7613(1974)2<395:AFAHET>2.0.CO;2
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Near-bottom investigations with a deep-towed instrument package show that steep-sided, flat-floored furrows (1 to 100 m wide by 0.5 to 20 m deep) eroded into Holocene and Pleistocene hemipelagic mud are responsible for the characteristic hyperbolic echo traces on surface-ship echograms recorded over the Bahama Outer Ridge (water depth, 4 to 5 km). This echogram character, previously interpreted as being caused by side reflections from depositional wave forms, has been typically recorded in abyssal regions of contour-current activity. It is suggested that these remarkably straight longitudinal furrows are formed by secondary helical circulations in the bottom-boundary mixed layer.