Bahamas beachrock

Figure 6.6. Photomicrographs of common marine cements. A) Whalebone Bay, Bermuda, 3m water depth. B) Beachrock from the Bahamas. C) Subaerial Holocene from the Bahamas. (Photomicrographs courtesy of R. Perkins.)...

Bain, R.J. (1988) Exposed beachrock its influence on beach processes and criteria for recognition. Proceedings of the 4th Symposium on Geology of the Bahamas, San Salvador, pp. 33-44. 

Kindler, P. Bain, R.J. (1993) Submerged upper Holocene beachrock from San Salvador Island, Bahamas implications for recent sea-level history. Geologische Rundschau 82, 242-247. 

My own experience in Joulter s Cay, Bahamas, reflects the rapidity of marine carbonate cementation in a beachrock setting (Friedman, 1998). Over a period of 10 yr, together with students and professional geologists I visited Joulter s Cay once a year. A year after one of our visits we found a sardine can from a previous visit. The cementation of the particles (ooids) was surprising. A bivalve shell had become cemented to ooids which had lithified on the underside of the can. 382 g of ooids and skeletal material had filled the can and lithified therein or had become cemented to the outside of the can (Friedman, 1998). This process is remarkable for 1 year s residence and contrasts with textbook statements that time is needed—cementation probably requires substantial amounts of time (Tucker and Wright, 1990, p. 325). 

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