Upper miocene planktonic foraminifera from Ekti Bay, little Andaman island

Abstract

Forty species and subspecies of planktonic Foraminifera are recorded from the 10 m sequence exposed along the cliff section in ttie southern part of Ekli Bay, Little Andaman island. The strata exposed are highly calcareous, light grey siity muJstoiie and yielded rich foraminiferal assemblages. The presence of Neoghboquadrina acostaeiuis unaccompanied by Globurotaiia piesiotu-mida in the lower 4.J thick sequence suggests this part of the section to be correctable with the Neogiuboqitadrlitu icosteemis Zone (Srinivasan, 1977, 1988). The first appearance of Glohoroialia pU'aivtumida at about 4.5 m above the base of the exposed section, delineates the N. acostoenshf Cr. piemtumidd zonal boundary, No specimens referable to PuUeniatina primaiis are recorded and the assemblage of the youngest sample examined is thus within the Glohorotalia plesiotumida Zone. The foraminiferal evidence suggests the marine sequ:ncc exposed at the Ekti Bay to represent the Neillian Stage (Upper Miocene).