Berriasian to lower Hauterivian palynostratigraphy, U.K. onshore and Outer Moray Firth

Abstract

Detailed palynofloral analysis of Lower Cretaceous sections at Speeton (northeast England) and in the UKCS Outer Moray Firth has involved 31 outcrop samples and over 1100 well samples fromGolden Eagle Field (UKCSblocks 14/26a and 20/01), including extensive conventional core.Very close sampling, particularly within theValanginian, has allowed some assessment of inter- and intra-species trends, some very short-lived and others of longer duration and the possible origins of several species are discussed. Paleoenvironmental change is seen as a possible stimulus to these evolutionary trends. The zonation scheme proposed by Duxbury (2001) has been re-visited and significantly refined. Recognition of additionalmarker events has allowed the further subdivision of several zones to sub-zonal level, allowing a better understanding of the stratigraphy, particularly of the Valanginian. Over 100 key palynofloral events have now been recognised between the top Berriasian and lower Hauterivian, including many first occurrences. One genus and twenty-one species of stratigraphically significant dinoflagellate cysts are described as new. Eight new combinations have been effected and the diagnoses of one genus and three species have been emended. The very high resolution achievable by applying the refined scheme is clearly demonstrated in two transects across the Golden Eagle Field.