Australia

CARPENTARIA BASIN

Industrial Project: New key-elements of the Barremian – Aptian transgression in the Carpentaria Basin (Queensland, Australia).

The main objective of this project is the multi-proxy study of the fluvial-deltaic siliciclastic Yappar Member, the lower part of the Cretaceous Gilbert River Formation. New biostratigraphic analyses based on pollen grains and dinoflagellate cysts and sedimentological correlations suggest that the Yappar, Coffin Hill and Wallumbilla formations could correspond to proximal to distal facies during the Barremian-Aptian transgression in the basin.

CANNING BASIN

Industrial Project: Biostratigraphy and geodynamic evolution of the North Canning Basin (Western Australia) during the Triassic.

Selected samples from two cored holes were analyzed from the palynological point of view. The basal part of both cores is dominated by Alisporites (Falicsporites), Aratrisporites spp., Densoisporitesand Playfordiaspora velata, with minor portions of Lundbladispora spp. This floristic assemblage is replaced in the middle part of the holes by Alisporites, other bisaccate pollen grains and ornamented trilete spores. The top of the studied holes shows FADs of Dictyophylllidiites mortonii, Ashmoripollis reducta, Minutosaccus crenulata and Limbosporites denmeadi.

The identified taxa and the negative evidence of the taeniate (striate) pollen grain provide robust evidences that none of the samples is older than Triassic. These assemblages are consistent with the Triplexisporites palyfordii Oppel Zone. The boundary to the immediately older Protohaploxypinus samoilovichii Oppel Zone is transitional, but the presence of Falcisporites australis, spiny forms of Aratrisporites and the occurrence of other lycopsid spores suggest that this belongs to the Triplexisporites palyfordii Oppel Zone of Spathian-Anisian age. For the youngest studied samples, we may propose a Ladinian age with respect to the S. quadrifidus Zone.