膏盐环境中未成熟石油成因初探

PRELIMINARY STUDY ON THE ORIGIN OF IMMATURE OIL IN EVAPORITIC ENVIRONMENT

作者根据目前国内外发现的未成熟石油与蒸发膏盐环境有关的事实,如江汉盆地的广33井潜一段未成熟石油、长庆临深2井的未成熟石油、以色列希克马(Shiqma)地区第三系未成熟石油等。对膏盐环境中未成熟石油的成因进行探讨.本文对目前提出的成因观点——强还原环境有利于有机质早期保存、早期转化和有机质类型控制的观点,进行了简介和评述;尔后根据埃及苏伊士湾蒸发沉积中的生油特征,提出了蒸发盐成油向上运移形成未成熟石油的可能性。

Based on the facts that immature crude oils discovered at home and abroad are related to the environment of evaporates, ex. the oil in the 1st section of the Qianjiang Formation encountered by Huan No. 33 well in the Changqing Oilfield, the Tertiary immature oil in Shiqma region of Isreal, etc. The origin of immature crude oils in evaporitic environment is studied in this paper. The author briefly introduces and reviews the following opinions on the origin of immature oil proposed recently. 1.strong reductive environ-ment is favourable for the preservation and the transformation of organic matter in early stage, and 2.the types of organic matter are the prerequisite of the formation of immature oils. Thereafter, it is suggested that the oil generated in evaporates may firstly migrate upwards and then changes into an immature oil, based on the study of the oil generated in the evaporitic sediments of the Gulf of Suez, Egypt.