Part 1. Organic Geochemistry in Petroleum Exploration: Organic Geochemistry in Petroleum Exploration. Relationship between crude oil quality and biomarker patterns, W B Hughes & A G Holba. Maturity related mixing model for methane, ethane and propane, based on carbon isotopes, U Berner & E Faber. The relationship between silica minerals and organic matter diagenesis: its implication for the origin of oil, K Taguchi et al. The Role of Geochemistry in Basin Modelling. Basin modelling - a new comprehensive method in petroleum geology, D H Welte & M N Yalcin. Geochemical modelling in rapidly subsiding basins, M A Chiaramonte et al. Regional Geochemical Studies: Case Histories. Oil generation and migration in the Gifhorn Trough, NW Germany, Th Schwarzkopf & D Leythaeuser. Aspects of depositional processes of organic matter in sedimentary basins, A Y Huc. Part 2. Analytical Geochemistry: Biological Markers in Recent and Ancient Sediments. Early diagenetic pathways of steroid alkenes, T M Peakman & J R Maxwell. Biomarker characteristics of nonmarine oils in China, Fan Pu & Zhang Baisheng. Differences in reactivities of sedimentary hopane diastereomers when heated in the presence of clays, A V Larcher et al. Paleoenvironmental Assessment. Bacterial reworking of sedimentary lipids during sample storage, J O Grimalt et al. Environmental control of carbon isotope variations in Pennsylvanian black-shale sequences, Mid-continent, USA, L M Wenger et al. Quantitative Aspects of Hydrocarbon Generation Reactions. Kinetic modelling of oil cracking, P Ungerer et al.