雪峰山西侧盆山过渡带油气成藏地质特征和破坏类型

对雪峰山西侧盆山过渡带油气成藏的基本特征进行了总结，划分出该区在燕山—喜马拉雅期强烈构造改造作用下可能残存的5套含油气组合。总结了区内典型的成藏特征，提出该区下古生界地层中油气具有多源供烃、多期成藏特征，并经历了“古油藏”阶段，构造隆升剥蚀作用是造成油气保存条件不好的重要因素。提出在晚期构造强烈改造区中也存在油气保存条件相对较好的地区，这类地区主要位于“隔槽式”褶皱主背斜的断层下盘、两翼潜伏构造及复向斜等下寒武统、下志留统区域性泥岩盖层分布地区。研究区地层中存在原生、次生、再生型油气藏，无论哪类油气藏，“构造型油气藏”在构造强烈改造后保存下来的几率变小，“非构造型油气藏”(主要是岩性油气藏)保存下来的几率较高。通过分析研究区古油气藏的破坏条件，提出了五大类10亚类油气藏破坏类型划分方案，指出研究区存在多种破坏类型的古油藏。

An analysis of geological characteristics and destruction types of hydrocarbon accumulation in the basin-mountain transitional zone on the western side of the Xuefeng Mountain

According to the researches on paleo-reservoirs in the basin-mountain transitional zone on the western side of the Xuefeng Mountain, this paper has summed up the basic characteristics of hydrocarbon accumulation, and recognized five petroleum-bearing combinations that might exist residually under the action of Yanshanian-Himalayan strong tectonic transformation. The typical reservoir-forming characteristics in this region is summarized. It is indicated in this paper that the hydrocarbon in lower Paleozoic sediments has the features of multiple-source hydrocarbon supplying and multi-stage hydrocarbon accumulation, the hydrocarbon experienced the stage of paleo-reservoir, and the tectonic uplift and erosion constituted the important factors for the unfavorable preservation conditions of hydrocarbon. Additionally, the preservation conditions of hydrocarbon are different in different regional cover residual zones and different tectonic parts. It is pointed out that there also exist some areas where the preservation conditions of hydrocarbon is relatively good in the strong late tectonic transformation region. These areas are mainly located in the fault footwall of the trough-like fold anticline, buried structures on flanks and synclinoria where the regional mudstone cap rocks composed of lower Cambrian and lower Silurian strata are distributed. Through the analysis of hydrocarbon accumulation and failure types, it is concluded that there are primary, secondary and regenerated reservoirs in the formation of the study area. Whatever the reservoir is, the probability that tectonic reservoir was preserved after the strong transformation of the tectonic reservoir is very small in the study area; nevertheless, the probability for the preservation of non-tectonic reservoirs (mainly the lithologic reservoirs) is relatively large. The classification scheme for five large classes and ten subclasses of reservoir failure types is proposed in this paper on the basis of an analysis of the failure conditions of the paleo-reservoir in the study area, and it is also indicated that there are many failure types of paleo-reservoirs.