【作者】 谭静；

【导师】 陈孔全； 罗劲；

【作者基本信息】 长江大学 ， 地质工程， 2018， 硕士

【摘要】 构造是制约油气成藏的关键,多期次的盆地演化与构造运动的叠加产生了成因多样的构造样式和成藏规律复杂的油气藏。本文以地震、测井、钻井和野外露头等资料为基础,应用构造地质学、构造年代学、大地动力学以及前陆冲断带与断层相关褶皱理论,通过复杂断裂带先进地震解释技术和平衡地质剖面分析技术等手段,建立江汉平原区结构模式,并系统阐明其构造特征和变形方式;对比南北两套构造体系演化史,综合分析不同构造区带构造变形与油气保存关系,为本区的油气勘探提供理论依据。在精细的地震资料解释基础上,通过对江汉平原及其周缘地区构造特征分析,江汉平原及其周缘地区形成了由秦岭-大别构造带和江南-雪峰构造带南、北两个弧形构造系联合而成的复合盆山体系,以“南北对冲、叠加和干涉”为特征,具“两山夹一盆”结构,构造形态总体呈前展对冲式逆冲推覆薄皮构造样式。根据构造形态和变形特征将研究区分为三大构造体系:南部构造体系、北部构造体系和南北对冲干涉带,并划分出1个一级构造单元,3个二级构造单元和8个三级构造单元。其中,三级构造单元可进一步分为6个四级构造单元。根据构造形变的力学性质、应力传递方式和几何样式等,将研究区构造样式划分为挤压收缩型构造、走滑压扭型构造和伸展反转型构造三大类。根据断层的性质、规模大小和空间展布特征将研究区断层分为三个系统:NNW或NW向、NE或NEE向和近EW向,总体受江南-雪峰构造带和秦岭-大别构造带联合作用影响,不同展布方向的断层其构造演化过程也不同。基于秦岭-大别造山带、江南-雪峰造山带和黄陵隆起等边界条件的具体分析,结合区域地层不整合接触关系和构造应力场资料,通过地震构造分析技术和平衡剖面技术综合分析认为江汉平原区中-新生代构造演化可划分为加里东-海西期、早燕山期、晚燕山期-早喜山期以及晚喜山期四个时期,其中早燕山期又可以分为两个幕次。构造格局控制油气的聚集和保存。根据复杂构造变动区油气的垂向保存思路,结合不同构造带构造变形特征及其演化史,以印支面地层赋存状况、构造与保存条件和匹配关系等作为优选油气保存有利区带的重要参数,综合分析认为宜昌稳定带、当阳滑褶带西部早期位于古隆起及周缘,现今构造相对稳定,变形较弱,发育的断裂较少,局部构造较发育,保存条件较好,为有利的勘探区带。更多还原

【Abstract】 Structure is the key to restrict hydrocarbon accumulation.There is a structural styles of various cause and the oil and gas reservoir of complex reservoir-forming rule,because of the multi-stage basin evolution and the multi-stagetectonic movement resulted in the complexity of oil gas evolution in Mesozoic and Paleozoic in the Jianghan Plain,and it effect on the Oil and gas exploration in this area.On the Basis of seismic,logging,drilling data and field outcrop data,the study,which is guided by tectono geology,tectonic geochronology,geodynamics and foreland thrust belt theory,apply the balanced geological section technology and the advanced seismic interpretation technology which is applied to complex fault zone to establishing the texture and structure model of Jianghan plain.Besides,for the comprehensive analysis of the relationship between structural deformation and oil and gas preservation,the research also systematically has illustrated textural characteristics and tectonic deformation features,and contrasted the difference of tectonic deformation between the two sets of tectonic systems,and it’s can provide theoretical basis for oil and gas exploration in this area.On the basis of fine seismic data interpretation,Jianghan Plain and its surrounding areas by the analysis of structural features is formed in the Qinling-Dabie tectonic belt and Jiangnan-Xuefeng tectonic belt under the action of two opposite extrusion.Since the Indosinian period,tectonic evolution and tectonic framework of Jianghan Plain both in the northern Qinling-Dabie orogenic belt and the southern Jiangnan-Xuefeng orogenic belt joint function of restriction,makes the Jianghan Plain in forming the composite joint pattern of multiple tectonic system.According to the structural deformation characteristics and structural forms of the study area,the Jianghan Plain can be divided into three tectonic zones: the southern tectonic zone,the northern tectonic zone and the North-South hedging interference zone,these zone can further organised into 9 three tectonic units.And both Dangyang depression belt and the Jingzhou Mianyang hedging interference zone can be divided into two four structural units respectively.Bassed on the characteristics of the mechanical properties of structural deformation,the mode of stress transfer and the geometric style,the structural styles of the study area are divided into three categories,namely,squeezing contraction structure,strike slip and compression torsion structure,extensional inversion type structure.The spatial distribution of fault in the study area is divided into three systems: NNW or NW direction,NE or NEE direction and near EW direction,which are affected by the joint effect of Jiangnan-Xuefeng orogenic belt and Qinling-Dabie tectonic belt,and the tectonic evolution process of different distribution directions is also different.By specific analysis of the boundary conditions such as the Qinling-Dabie tectonic belt,the Jiangnan-Xuefeng orogenic belt and the Huangling uplift,the Mesozoic and Cenozoic tectonic evolution in the Jianghan plain area can be divided into Caledonian Hercynian,early Yanshan,late Yanshan and early Himalayan periods,combining regional stratigraphic unconformity contact relationship,tectonic stress field evolution,seismic tectonic analysis and balanced section technique.There are four periods in the late Himalayan period,and the early Yanshan period can be divided into three episodes.The structural pattern controls the accumulation and preservation of oil and gas.By comprehensive analysis both evolution history and tectonic deformation features of different structural belts,It is considered that the Yichang stable zone and the early Western Dangyang fold belt are located in the paleo uplift and the periphery in the early stage.The current structure is relatively stable,the deformation is weak,the local structure is more developed,the preservation is better,and it is a favorable exploration zone.更多还原