有效烃源岩下限指标初探

DISCUSSION ON LOWER LIMIT OF CONTENT OF ORGANIC MATTERS FOR EFFECTIVE SOURCE ROCKS

有效烃源岩下限标准是大家长期争论的问题,各界学者在评价有效源岩时采用的有机碳下限标准各异。本文从有效烃源岩的概念、限制条件着手,从国内外油气勘探的发现入手,以大量国内外已发现油气田(藏)已知的有效烃源岩统计数据为依据,结合源岩成熟度参数,提出有效烃源岩评价标准是:灰岩有机碳含量≥0.3%;泥灰岩有机碳含量≥0.5%;泥岩有机碳含量≥1.0%;油源岩成熟度上限指标Ro≤1.5%;气源岩成熟度上限指标Ro≤4.0%。

Standard of lower limit of content of organic matters for effective source rocks is a long standing problem and different scholars give different answers when they are assessing effective source rocks. Based on the concept and limited conditions of effective source rocks, the petroleum exploration practice, and statistatic data of effective source rocks in known oilfields in the world, combining with maturing of source rocks, it was suggested that for effective source rocks, content of organic matters in limestone should be larger than 0.3%, ≥ 0.5% in marls and ≥1.0% in mudstone, and maturity for oil R_o ≤ 1.5% and for gas R_o≤ 4.0%.