Origin of Florida Canyon and the role of spring sapping on the formation of submarine box canyons

Geological Society of America Bulletin
By: , and 

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Abstract

Florida Canyon, one of a series of major submarine canyons on the southwestern edge of the Florida Platform, was surveyed using GLORIA, SeaBeam, and Deep-Tow technologies, and it was directly observed during three DSRV Alvin dives. Florida Canyon exhibits two distinct morphologies: a broad V-shaped upper canyon and a deeply entrenched, flat-floored, U-shaped lower canyon. The flat- floored lower canyon extends 20 km into the Florida Platform from the abyssal Gulf. The lower canyon ends abruptly at an ∼3 km in diameter semicircular headwall that rises 750 m with a >60° slope angle to the foot of the upper canyon. The sides of the lower canyon are less steep than its headwall and are characterized by straight faces that occur along preferred orientations and indicate a strong joint control. The upper canyon is characterized by a gently sloping, straight V-shaped central valley cut into a broad terrace. The flat floor of the upper canyon continues as terraces along the upper walls of the lower canyon. On the flanks of the upper canyon, there are five >50-m-deep, >0.5-km-wide, closed sink-hole-like depressions which indicate subsurface dissolution within the platform. The origin of the lower canyon is difficult to explain with traditional models of submarine canyon formation by external physical processes. The movement of ground water, probably with high salinities and reduced compounds along regional joints, may have focused the corrosive force of submarine spring sapping at the head of the lower canyon to produce the canyon's present shape.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Origin of Florida Canyon and the role of spring sapping on the formation of submarine box canyons
Series title Geological Society of America Bulletin
DOI 10.1130/0016-7606(1990)102<0502:OOFCAT>2.3.CO;2
Volume 102
Issue 4
Year Published 1990
Language English
Publisher Geological Society of America
Contributing office(s) Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center
Description 14 p.
First page 502
Last page 515
Country United States
Other Geospatial Florida Canyon
Online Only (Y/N) N
Additional Online Files (Y/N) N