A palynostratigraphic classification of the Westphalian of the southern North Sea carboniferous basin
Based upon the examination of the palynostratigraphy of 28 well sections and 6 multi-well studies, the Westphalian sequences in the Southern North Sea Carboniferous Basin are divided into 7 biozones and 12 sub-biozones. These are related, via the known regional northwest European palynostratigraphy, to the chronostratigraphic units of the Westphalian. Analysis of 164 palynological samples from Westphalian sections in the Murdoch Gas Field wells 44/22-1,44/22-3 and 44/22-4, coupled with the recognition of diagnostic macrofossil faunas indicative of the Vanderbeckei Marine Band, allows the direct calibration of part of the palynostratigraphic classification with the chronostratigraphy. Palynological assemblages from these wells contain significant numbers of acritarch and miospore taxa interpreted as being reworked from Lower Palaeozoic, Devonian and early Namurian sediments, possibly during multiple phases of reworking. Assemblages also contain unusually old examples of striate disaccate and monocolpate pollen. One new genus (Ala rasmospo rites) and eighteen new species (Auroraspora? pickerillensis, Dibolisporites ranunculioides, Elaterites anfractus, Endosporites pygmaeus, Hymenospora murdochensis, Knoxisporites biceps, Kraeuselisporites crassus, K. pseudoornates, Marasmosporites semiesus, Neoraistrickia exigua, N. virgultorum, Pityosporites inaequus, Protohaploxypinus masonii, Raistrickia parvula, Savitrisporites semotus, Spelaeotriletes oppletus, S. bulboides and Vestispora dubia) are described.