ABSTRACT: Quantitative palynofloral analysis of Hauterivian and early Barremian aged sediments at Speeton (northeast England) and in the UKCS,Witch Ground Graben has involved 39 outcrop samples and over 1000 samples from 40 wells in the Northern Area Claymore (NAC), Scapa and Highlander fields, including extensive conventional core. Very close sampling, particularly within the early Hauterivian at Speeton, has allowed dinocyst events to be tied closely to ammonite zones and their extrapolation offshore. The timing of deposition of the Scapa Sandstone Member of the Valhall Formation is discussed for Scapa Field, and a transect across the field is presented. Individual Scapa sedimentary units have been assigned to particular ammonite zones and the timing of paleoenvironmental changes at Speeton assessed in relation to them. The zonation scheme proposed by Duxbury (2001) has been re-visited, further refined and some boundaries adjusted, particularly in relation to ammonite zone equivalence. Eighty-five key palynofloral events have now been recognised in the Hauterivian and early Barremian, including many first occurrences. Thirty-seven new species and seven new subspecies of stratigraphically significant dinoflagellate cysts are described, four new combinations have been effected and the status of one taxon has been raised from subspecies to species rank. The diagnoses of one genus and one species have been emended.

Files