Mid-Cretaceous Foraminiferids from the Wahgi Valley, Central Highlands of Papua New Guinea

Abstract

Albian-Cenomanian foraminiferids are recorded from a tuffaceous sandstonemudstone unit (Kondaku Tuff and Chim Formation), which is exposed on the northern limb of the Kubor Anticline in the Central Highlands of Papua New Guinea. During the Cretaceous, this region was at the northern edge of the Australian continent. The fauna is dated by planktic species: Ticinella cf. primula of the middle and late Albian; Planomalina buxtorfi of the latest Albian to earliest Cenomanian; and Rotalipora aff. greenhornensis and R. aff. deeckei of the Cenomanian. Variation in relative abundance of siliceous textulariines is considered to be largely the result of dissolution of calcareous shells during sediment diagenesis. The original fauna apparently contained diverse textulariine-rotaliine assemblages which reflect warm, open-sea conditions perhaps on the upper continental slope. The benthic species are representative of the Marssonella Association and include many forms widely distributed in both Southern and Northern Hemispheres. Mid-Cretaceous foraminiferids from the Wahgi Valley, Central Highlands of Papua New Guinea