Black benthic foraminifera in carbonate fades of a coastal sabkha, Saudi Arabian red sea coast

Abstract EN

Black foraminifera occurs in the zone of mixing of carbonate and terrigenous sediments of the coastal sabkha, Saudi Arabian Red Sea coast.

The blackening may be due to impergenation of the sediments by dis-solved or finely particulate iron sulphides (pyrite).

The iron appears to be derived from associated terrigenous sediments and is being precipitated under reducing conditions and in the presence of ulphate-reducing bac-teria around centers of organic material such as the foraminifera tests in the sediments.

This black material is found preferentially on test surfaces of foraminifera or along sutures.

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