Abstract The West Flower Garden Bank is located in the northwest part of the Gulf of Mexico at lat. 27°52.6’N, long. 93°49.0’W. It is one of more than 100 knolls that exist on the outer continental shelf between the Mississippi Canyon and Corpus Christi, Texas. The reef has been surveyed and sampled by surface océanographie vessels. It has also been observed and sampled using a submersible.
The living reef rises from a depth of 45 m to a crest at 20 m. Its faunal composition places it in the Diploria-Montastrea-Porites zone of typical West Indian reefs. Surrounding the reef, from a depth of about 45 m to 90 m, is a gently sloping sediment apron. The facies that occur on this apron are: (1) coral debris, 45-51 m; (2) algal nodule, 51 -73 m; (3) Amphistegina, 73-91 m; and (4) quartz -planktonic foraminifers, below 91 m. Three dead barrier-reef levels have been found at depths of 56, 91, and 127 m. Behind these reefs are scattered dead patch reefs in various stages of burial by surrounding sediments.
The levels of the dead reefs coincide quite well with published sea-level curves. Detritus recovered in a core from the 91-m reef was dated at 19,300 ± 400 years B.P. Pétrographie examination of reef detritus from this level shows that cementation by marine prismatic calcite was followed by freshwater vadose cement. This observation supports Logan’s contention that late Wisconsin sea level stood at approximately —91 m and that there was a rapid withdrawal to —127 m, followed by a transgression to the present level that began about 18,000 years B.P. The last transgression was interrupted by pauses and/or possible reversals.
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Reefs and Related Carbonates—Ecology and Sedimentology
Studies in Geology 4: Reefs and Related Carbonates–Ecology and Sedimentology