Two stratigraphically equivalent Upper Kimmeridge outcrops were compared by petrological and geochemical means. Maturity, type and source of the organic matter and palaeoenvironment were studied and compared.
The sites chosen were Marton North Yorkshire and Kimmeridge Bay Dorset, the type section some 300Kms, to the south. The results are part of a continuing study of these onshore Kerogen-rich oil shales, mudstones, clays and coccolith limestone alternations.
The results are in agreement with maturity findings of Williams and Douglas, (1980, 1981and 1983) and Jones (1980). The Dorset samples showed little terrestrial influence and molecular distributions were broadly similar with minor variations in 4 methylsteroidal hydrocarbons and n-alkane maxima. This is in broad agreement with Farrimond et al., (1984), and is in agreement with the palaeoenvironmental model proposed by Tyson et al. 1, (1979). The more mature Marton samples in contrast have a strong terrestrial overprint, were deposited in an oxic environment and contained bisnorhopane which is absent in Dorset.