有机相在油气源岩与油气评价中的作用——以下扬子区二叠系为例

本文根据沉积相、沉积物源、生物组合、地球化学相、有机质丰度和类型、生烃潜力等特征对下扬子区二叠系的主要油气源岩有机相进行综合研究,同时阐明有机相的概念,提出有机相的划分依据和指标界限,将有机相分为强油相(A)、油相(B₁)、油裂解气相(B₂)、油气混合相(B-C)、无油气相(D). 

THE ROLE OF ORGANIC FACIES IN EVALUATION OF SOURCE ROCKS AND OIL/GAS-A CASE STUDY IN THE PERMIAN SYSTEM OF LOWER YANGTZE

On the basis of the features of sedimentary facies,material source,biological assemblages,geochemical facies,the abundance and types of organisms,hydrocarbon potential,etc.,the paper makes a comprehensive study on the organic facies of major oil-gas source rocks in the Permian system of the Lower Yangtze Region.Meanwhile the concept of organic facies is proposed.It is suggested that the organic facies can be clarified into subfa-cies of highly oil-prone phase(A),oil-prone phase(B₁),gas-prone phase by oil cracking(B₂),oil-gas mixing phase(B-C),oil/gas barren phase(D)respectively in accordance with the classification of organic facies and their indices.