Uppermost Jurassic-lower cretaceous radiolarian chert from the Tanimbar Islands (Banda Arc), Indonesia

Abstract

This paper describes and figures Mesozoic Radiolaria from cherts in Pulau Ungar, Tanimbar Islands, eastern Indonesia. Two assemblages of Radiolaria are recognised. The lower assemblage is indicative of upper Tithonian (uppermost Jurassic) to Berriasian (lowermost Cretaceous) and the upper assemblage is of upper Valanginian to Barremian age. These are the first precise ages obtained from the Ungar Formation, a unit including sandstones with apparently good petroleum reservoir characteristics.