曲面型断层的露头特征及其地质意义

曲面型断层与平面型断层相比,发育特征和形成机理更加复杂,与盆地形成演化的关系更加密切,且构造样式更易于矿产的富集,对其开展研究显得更为重要。以新泰-垛庄大断裂为例,通过详尽的露头定性定量地质数据分析,得出断层两盘的岩性、产状以及断层面的擦痕、产状、运动学性质等是揭示曲面型断层发育特征的几大要素。断层控制盆地的性质、形成演化以及现今格局,与此同时,受到盆地沉积—剥蚀旋回和构造应力场的影响,造成断层曲面的形成。研究结果表明,在相互影响和相互作用的过程中,断层曲面形成圈闭,易于油气等流体矿产成藏;同时盆地沉陷中心的迁移造成煤等固体矿产的富集。

Outcrop characteristics of curved fault and its geological significance

Compared with planar faults,curved fault's development characteristics and formation mechanism are more complicated,and the relationship of the formation is closer with the evolution of the basin,whose structure styles are easier to enrich the minerals.As a consequence it is more important to carry out the research.In this paper,taking large Xintai-Duozhuang Fault as an example,qualitative and quantitative geological data of detailed outcrop show that the lithology and occurrence of both sides of the fault together with scratches,occurrence and kinematic properties of the fault surface are the main elements of the development characteristics of curved fault.The fault controls the characteristics,formation,evolution and current pattern of the basin.Meanwhile it is also affected by the deposition-abrasion cycles and structural stress fields of the basin,resulting in the formation of its crrved surface.The results show that in the process of interaction,the fault surface forms traps,which makes them easy to accumulate oil or other fluid minerals.At the same time,the migration of subsidence center of basin causes the enrichment of coal or other solid minerals.