Evaluation of methods for retrieving foraminifera from indurated carbonates: application to the Jurassic spongiolithic limestone lithofacies of the Prebetic Zone (South Spain)

Abstract

Two methods for retrieving foraminifera from strongly lithified carbonates (Amine-O and cold-disaggregation with acetic acid) were tested on the same sample of Oxfordian spongiolithic limestone (Prebetic Zone, SE Spain) and compared with thin section analysis. Differences between the methods concern: 1) weight of sieved residues after disaggregation; 2) foraminifera/gram ratio; 3) preservation features of the tests; 4) foraminiferal assemblage compositions. The results obtained allow us to conclude that accurate paleoecological and taxonomical analysis of indurated carbonates requires the combined use of thin sections and disaggegration treatment of the samples.