含有不整合面的钻井剖面中酸解烃的垂向分布规律

VERTICAL DISTRIBUTION OF ACIDOLYSIS HYDROCARBON IN WELL LOG WITH UNCONFORMITY

系统测量了不同时代、不同埋深的不整合面钻井剖面中酸解烃的分布,发现不整合面之下发育有总烃、甲烷浓度低而大分子烃类相对富集的烃类异常带,分析认为此异常带是风化脱气作用形成的脱气带,其厚度与下伏地层成岩程度有关。该发现对评价含油气盆地剥蚀与气藏保存、破坏的关系,不整合面对油气运聚的影响等有重要意义,也为解决剥蚀量恢复问题提供了新的科学线索。

Based on systematic measurement of the distribution of acidolysis hydrocarbon in well log with unconformities of different epochs and different depths,the authors found that under the unconformity surface there is an abnormal distribution zone of hydrocarbon which has low total abundance of hydrocarbon,low concentration of methane and relative enrichment of hydrocarbon macromolecules.It is considered that this anomalous zone is a degassing zone formed by weathering and degassing,and its thickness is related to the diagenetic degree of the lower strata.This discovery has great significance for evaluating the relationship between the basin erosion and the gas reservoir preservation or destruction as well as for studying the effect of the unconformity on oil and gas migration,and also provides a new scientific clues for solving the problem of restoration of denuded strata.