南阳凹陷同生断层研究

南阳凹陷是南阳—襄樊新生代盆地的组成部分,不整合叠置在华北地块、秦岭构造带、扬子地块之上,经历了早第三纪沉降、早一晚第三纪间的隆起和晚第三纪—第四纪沉降3期活动。本文根据本区早第三纪形成、活动的生长断层参数的统计、分析了断裂长度、延深、落差间的数学关系。在分析、确定几条主要生长断层性质的基础上,结合区域地质背景,讨论了控制南阳凹陷形成的构造应力场的基本特征。对于进一步研究断层的形成机制和石油勘探工作具有参考价值。

A STUDY OF THE SYNGENETIC FAULTS OF NANYANG DEPRESSION

Nanyang Depression is an integral part of the Nanyang-iangfan Cenozoic Basin and it unconformally superimposed on the Huabei massif, Qinling tectonic zone and Yangzhi massif. It has undergone three activity stages, i. e. the subsidence in early Tertiary period, the uplift between early Tertiary and late Tertiary period, and the subsidence in late Tertiary to Quaternary period. According to the parametric statistics of fifty eight pieces of normal faults which were active in early Tertiary period, the mathematic relationships between the length, depth and throw of the faults are analysed. Otherwise, on the basis of the recognition of some syngenetic faults considering the regional data, the main characteristics of the tectonic stress field controlling the Nanyang Depressin are discussed.