An Attempt to Apply Geobiological Method in the Source Rock Evaluation

摘要

Chinese marine carbonate rocks possess some common characters unfavorable for their traditional evaluation as hydrocarbon source rocks. Most of them are pre-Jurassic and have experienced multi-phase geothermal disturbances and structural deformations. Consequently, low abundance of organic matter (TOC mostly <0.2%) and high maturation (Ro largely >1.5%) prevail in these rocks, hindering the application of most organic geochemical parameters in their assessment. Total organic carbon (TOC, %), the only parameter remain, has been proved uncertain to identify or deny Chinese carbonate source rocks, and the lower limit of TOC has been a disputable problem in their evaluation.