Relationship between petroleum generation, migration and sandstone diagenesis, Middle Jurassic, Gifhorn Trough, N Germany

摘要: Abstract The Gifhorn Trough in North Germany contains an interbedded succession of Lower to Middle Jurassic source and reservoir rocks. Regional variations the burial history made it possible investigate different stages maturation rocks diagenetic This study focuses particular on temporal spatial relation between secondary petroleum migration events sandstones. Reconstruction geothermal indicate initiation generation at beginning Upper Cretaceous. Toarcian shales have been identified as common rock all oils, based biomarker stable isotope studies. Differences composition maturity reservoired oils are interpreted be related separated oil kitchens maximum maturity, rather than in-reservoir alteration after accumulation. Major shallow marine, arenitic sandstones linked various processes operating during burial: (a) Fe-calcite cement formation — analyses that this is facies-related from carbonate redistributed depth (800–1200 m); (b) Fe-dolomite dolomitization early formed discussed pore water oxygen isotopic composition; (c) late kaolinite two models explain observed simultaneous creation minor amounts porosity; (d) quartz overgrowths diffusive silica transport grain dissolution into adjacent proposed a mechanism. Geochemical carbonate-cemented intervals suggest generated condensate was trapped precipitation, prior main phase migration. These horizons probably compartmentalized reservoir, controlled routes promoted traps.