The organic geochemistry of the Eocene–Oligocene black shales from the Lunpola Basin, central Tibet

摘要: Abstract This paper reports on the depositional paleoenvironment and potential hydrocarbons of Eocene–Oligocene black shales from Dingqinghu Niubao Formations in Lunpola Basin, central Tibet. Nineteen samples two outcrop profiles were analysed. The contents total organic carbon (TOC) sulphur measured; other analyses included Rock–Eval pyrolysis, solvent extraction gas chromatography–mass spectrometer (GC–MS). results indicated that are thermally immature. pyrolysis data show contain Type I matter lacustrine algal main sources. low pristane to phytane ratios high gammacerane indices indicate deposited a reducing, stratified, hypersaline palaeo-lake, which is consistent with climate information provided by development history palaeo-lakes Eocene Oligocene epochs.