南襄盆地地质结构与形成演化  

Geological Architecture and Tectonic Evolution of Nanxiang Basin

作　　者：李智[1,2] 张志业 李双建 熊健[2] 安艳君 LIZhi;ZHANG Zhiye;LI Shuangjian;XIONG Jian;AN Yanjun(SINOPEC Key Laboratory of Geology and Resources in Deep Stratum,Beijing 102206,China;SINOPEC Henan Oilfield Company,Nanyang 473400,Henan,China)

机构地区：[1]中国石化深部地质与资源重点实验室,北京102206 [2]中石化河南油田分公司,河南南阳473400

出　　处：《西北地质》2022年第2期116-127,共12页Northwestern Geology

基　　金：国家自然科学基金企业重点联合基金“盆地深部地质作用过程与资源效应”(U20B6001);国家自然科学基金企业创新发展联合基金“海相深层油气富集机理与关键工程技术基础研究”(U19B6003)资助。

摘　　要：南襄盆地是以古近系沉积为主的中—新生代含油气盆地,分析其地质结构和形成演化对盆地油气勘探和研究造山带之上盆地构造特征均有重要意义。笔者以重磁电、地震、钻井和测井资料为基础,系统分析南襄盆地的地层展布、构造特征和形成演化,探讨各凹陷地质结构差异的控制因素,分析盆地成因。通过研究认为,南襄盆地是由深大断裂分割的数个隆起和半地堑型凹陷组成,平面具分带、分块构造格局;垂向上由不整合面划分为基底、上白垩统、古近系、新近系—第四系4套构造-地层层序。其构造演化可划分为晚白垩世断陷初期—白垩纪晚期差异反转期、古近纪强烈断陷-廖庄组沉积末期强烈隆升剥蚀、新近纪拗陷期3个伸展-聚敛构造旋回。泥岩滑脱作用和基底性质差异导致的控凹边界断裂沉降差异,是盆地各凹陷地质结构差异的主控因素。南襄盆地是在晚白垩世以来北西—南东向剪切拉张应力场下地幔隆起和地壳下沉均衡作用下形成的简单剪切型伸展拆离盆地。Nanxiang basin is a Mesozoic-Cenozoic petroleum basin developed on the eastern Qinling fold orogenic belt in the late Yanshan movement and dominated by paleogene sediments. The analysis of geological structure and tectonic evolution plays a significant role in oil-gas exploration and structural research of basins above orogenic belts. Based on gravity, magnetism, electricity, seismic, drilling and logging data, guided by normal fault related fold theory and structural restoration theory, this paper systematically analyses the structural characteristics, stratigraphic distribution and tectonic evolution of Nanxiang basin, explores the controlling factors of geological structure differences in depressions, and analyses the origin of Nanxiang basin. It is considered that the Nanxiang basin is composed of several semi-graben depressions separated by deep and large faults and uplifts, with a tectonic framework of north-south zoning and east-west block and is divided into basement structural layer, upper Cretaceous structural layer, Paleogene structural layer and Neogene-Quaternary structural layer on the section. Its tectonic evolution can be divided into three extensional-convergent tectonic cycles: the Late Cretaceous fault depression-the Late Cretaceous inversion denudation, the Late Paleogene extensional rift-the Liaozhuang Formation inversion denudation and the Neogene depression period. The mudstone slippage and difference of the boundary faults caused by the difference of basement properties is the main controlling factors for the differentiation of geological structure in each depression of the basin. Nanxiang basin is a simple shear-type extensional detachment basin formed under the balance of mantle uplift and crustal subsidence under the NW-SE shear-tensile stress field since late Cretaceous.

关 键 词：南襄盆地 地质结构 构造演化 基底性质 断层特征 泥岩滑脱 

分 类 号：TE121.2[石油与天然气工程—油气勘探]