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von Rad U Haq B U et al 1992 Proceedings of the Ocean Drilling Program Scientific Results Vol 122 23 FIRST RESULTS OF LATE TRIASSIC PALYNOLOGY OF THE WOMBAT PLATEAU NORTHWESTERN AUSTRALIA1 Wolfram Brenner2 ABSTRACT Cores from Leg 122 Sites 759 760 761 and 764 were sampled at intervals of one sample per 1 5 m section in the Upper Triassic sequences Spores pollen acritarchs freshwater algae and dinoflagellate cysts were studied to establish a palynostratigraphic framework for the Late Triassic The palynological sequence is interpreted in terms of Australian spore pollen zones the Carman Samaropollenites speciosus Zone the Norian Minutosaccus crenulatus Zone and the Rhaetian Ashmoripollis reducta Zone The Samaropollenites speciosus Zone Minutosaccus crenulatus Zone boundary is marked by the change of pollen abundance and has a gradual character Therefore a transitional uppermost Carnian to Norian Samaropollenites speciosus Minutosaccus crenulatus Zone is used Age determining dinoflagellate cysts are present in the Norian and Rhaetian sediments INTRODUCTION During Leg 122 of the Ocean Drilling Program ODP nine holes were drilled at four sites Site 759 760 761 and 764 in a north south transect on the Wombat Plateau a small sub plateau of the northern Exmouth Plateau Fig 1 The oldest sediments drilled on the Wombat Plateau are late Carnian in age They are also the oldest marine sediments drilled during the 20 year history of Deep Sea Drilling Project DSDP and ODP drilling The sediment succession begins with late Carnian prodelta claystone and siltstone followed by deltaic marginal marine and fluvial nonmarine sediments in the uppermost Carnian and in the Norian Sites 759 and 760 Uppermost Norian sediments were recovered at Site 761 and Rhaetian sediments at Sites 761 and 764 The uppermost Norian consists of a carbonaceous claystone with coal seams The overlying Rhaetian sequence at Site 761 is comprised of crinoid limestone and laminated claystone facies Site 764 which is



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