SEDIMENTOLOGY, PALYNOSTRATIGRAPHY, PALYNOFACIES AND THERMAL MATURITY OF UPPER PERMIAN ROCKS OF KOLGUYEV ISLAND, BARENTS SEA, RUSSIA

The Upper Permian succession of Kolguyev Island contains five transgre ssive-regressive sequences. Depositional environments, determined from sedimentological data and palynofacies, include coastal plain, estuar ine, deltaic and beach, shoreface and shelf. The maximum depth of the shelf probably did not exceed 50 metres (slightly below the storm wave base). Sediment was derived from a nearby land mass. Two informal pal ynomorph assemblage zones are recognized in the succession. The older, Assemblage I, based on comparisons with the pollen and spore zones of the Sverdrup Basin, Canadian Arctic Archipelago, is of Roadian (Ufimi an?) age, and the younger, Assemblage II, is Wordian (Kazanian?) age. The floral province is Sub-Angara. The dominance and variety of trilet e pteridophyte spores, suggests that the parent vegetation was diverse , such as may inhabit a swamp environment. The climate on land was pro bably seasonably humid. The Thermal Alteration Index derived from spor e colouration is low (TAI 2- or Ro% 0.45) and lies in the biogenic met hane zone near the threshold of the ''oil window''. Source rock potent ial is low due to the scarcity of oil prone organic matter and the abu ndance of woody and coaly organic matter, and finely dispersed organic debris of mixed origin. The maximum depth of burial for the Upper Per mian rocks (assuming a standard geothermal gradient) did not exceed 2 km.