【作者】 肖朝晖；

【导师】 赵霞飞；

【作者基本信息】 成都理工大学 ， 矿产普查与勘探， 2010， 博士

【摘要】 本文以盆地流体化学-动力学、油气封存箱理论为指导,以构造演化和烃源岩热演化为主线,把握宏观与微观、地表地质与地下地质、静态研究与动态研究相结合的原则,按油气保存体系受盖-源共控的观念,进行油气保存体系的表象性、成因性、有效性分析,对中扬子区海相油气保存条件进行研究。依据野外调查及测试和钻井、测井、地球物理等资料,建立了中扬子区盖层综合特征基干剖面,研究区发育有泥质岩类和膏盐岩类盖层,存在下寒武统、中寒武统、志留系、中三叠统—侏罗系等4套区域盖层和下三叠统嘉陵江组等5套局部盖层;结合地表流体的分布特征、地腹水化学性质、水化学对应分析,并从盖层的封闭性能及其间的流体能量的相对独立性,揭示了油气保存体系自T₂-J→S→∈₂→∈₁,覆盖面积逐渐增大且呈“塔式”叠置结构。在构造演化研究基础上,对油气保存体系进行了“位、体”改造的成因研究。分析了加里东期、海西-印支期、早燕山期、晚燕山—喜山期等主要构造演化阶段盖层的演变特征与流体化学—动力学响应特征,认为盖层发育的沉积体系域、盖层成岩变质程度、盖层变形变位强度、流体宿主性是油气保存体系的主控因素。其中H型的海侵体系域、高水位体系域分别有利于泥质岩类、膏盐岩类优质盖层的形成;中寒武统、志留系盖层具有成岩变质适中的优势;下寒武统、中寒武统盖层具有变形变位强度小的特点;自江汉平原北东襄樊—广济断裂、京山—乌龙泉断裂向鄂西渝东区西部齐岳山断裂,断裂形成时间由早到晚,活动强度由强至弱;鄂西渝东区震旦系—三叠系缺少异源流体,流体宿主性好;远离断层的地区虽然早期具有下古生界异源流体的充注,流体宿主性较差,但在晚期流体充注时,早古生代地层与中生代地层中的流体互不连通,流体宿主性相对较好。在烃源岩热演化研究基础上,开展了油气保存体系“质、量”演变的有效性研究。印支期以来是油气保存体系的重要变革时期,对于∈₁、∈₂油气保存体系,晚印支-早燕山期烃源灶由干酪根裂解型向油裂解型转化的过程中,保存条件持续;对于S、T₂-J油气保存体系,早燕山期烃源灶虽然仍为干酪根裂解型,但受到构造活动改造强度较大,保存条件被削弱。油气保存体系纵向上优劣分异的序列是:∈₂→S→∈₁→T₂→J体系;横向上优劣变迁的序列是石柱、利川、桑植、花果坪、宜昌、沔阳、当阳体系。典型油气封存箱具有“构筑—改造—定型”动态特点,重点剖析了慈利南山坪震旦系、簰洲下寒武统、建南志留系、龙驹坝二叠系油气封存箱。总结出研究区油气保存存在连续—最终宿主、断续—接替宿主、残存—过渡宿主、推覆—（?）宿主四种模式。其中连续—最终宿主型,多套盖层叠置、无异源流体充注是油气保存的理想模式,建深1井志留系气藏为典型类型之一,其幕式闭合/开启旋回式的封闭机理诠译了志留系气藏韩家店组、小河坝组、龙马溪组层层含气的独特性,该气藏的封闭主要起源于异常高压,而高压封闭能力是薄膜封闭7倍之多,修正了以往认为“海相盖层埋藏深、成岩变质程度高、封闭性能差”的普遍观点。基于油气保存体系的表象性、成因性、有效性研究,建立了构造—沉积多旋回叠合、多期构造改造的中扬子区油气保存体系评价体系。以各个盖层油气保存体系为单元划分了有利勘探的保存区带及其目标。更多还原

【Abstract】 According to the theory of basin fluid chemistry-kinetics ,oil and gas compart ment, the main line of structural evolution and thermal evlution of source rocks,holding the principle of studying macro and micro、surface geology and subsurface geological and static and dynamic,the concept of oil and gas preservation system by the cover - the source of control, we analyze the appearance of oil and gas preservation system, causes, effectiveness and evaluate the preservation conditions of Marine oil and gas on the Yangtze Region .The author, based on field survey and testing and drilling, logging, and geophysical data,establish feature of caprock skeleton profile in the Middle Yangtze Region.The study area developed cover of muddy rocks and gypsum-salt rock, existed Cambrian, Middle Cambrian, Silurian, Middle Triassic - Jurassic, Cretaceous - Paleogene other five sets of regional seal and Lower Triassic Jialingjiang other five sets of local seal. Combined with distribution of the fluid surface、the overlying water chemistry、water chemistry correspondence analysis, and the relative energy independence between the cover closure and the fluid, revealed the oil and gas preservation system from T₂-J→S→∈₂→∈₁, covering an area of gradually increasing and was a "tower" the stacking structure.Based on the study in the tectonic evolution, it made the research on the cause of reform of oil and gas preservation system’s "bit, body." Analyzing the major cover tectonic stages of the evolution of the chemical characteristics and the fluid - dynamic response characteristics of the Caledonian, Hercynian - Indosinian early Yanshan period, late Yanshan– Himalayan,it thought that development of depositional systems that cover the domain , diagenetic metamorphic cover, cover deformation deflection strength of the fault, "Three" coupling, the fluid reservoir were the dominant factors of the oil and gas preservation system. In which H-transgressive systems tract, HST were conducive to the formation of muddy rock, rock salt, gypsum cap rock class quality; the Cambrian, the Silurian cap have the advantage of moderate diagenetic metamorphism; Lower Cambrian weapons systems, in the Cambrian cover has a deformation strength of the small deflection characteristics ;The fault from Jianghan North East Xiangfan - wide economic, Jingshan - wulongquan fracture of West Hubei and East West Qi Yue Mountain, whose formation time from early to late, activity intensity from strong to weak, the "triple" configuration relations of the fault obeys the trend of changing from non-coupled to the coupled; Western Hubei and East of the Sinian - Triassic lack of heterologous fluid, the fluid reservoir is of good quality ; the region far away from the fault is under the fluid filling of the Early Paleozoic with different sources ,the fluid reservoir is poor, but in the late fluid filling, the Early Paleozoic and Mesozoic strata in the fluid are not mutually connected, the fluid reservoir is relatively good .On the basis of the study of the Hydrocarbon source rocks, the effective research on the evolution of the oil and gas preservation system "quality, quantity,". The important reform period of oil and gas preservation system is from Indo-China, for∈₁,∈₂ oil and gas preservation system, the late Indo-China - Early Yanshan hydrocarbon kitchen cracked from the kerogen to oil-cracking type transformation process, storage conditions continue; for S, T₂-J oil and gas preservation system, the early Yanshan source kitchen, still a cracking of kerogen type, but the strength of a larger transformation by tectonic activity, preservation conditions are weakened..Advantages and disadvantages of oil and gas preservation system of vertical differentiation of the sequence is:∈₂→S→∈₁→T₂→J system; horizontal sequence is Shizhu, Lichuan, Sangzhi , Huaguoping, Yichang, Mianyang, Dangyang system.Typical oil and gas compartment has a "build - transformation - fixed" dynamic characteristics, importantly analyzes a Cili Nanshanping Sinian, Paizhou Lower Cambrian, Jiannan Silurian, longjuba Permian oil and gas compartment. Summarized in the study area hydrocarbon preservation include continuous - the ultimate host、intermittent - take over the host、survival - the transition host、thrust - （?） Host four modes.Especially the ultimate host type, multiple sets of cover overlay, the same as the source of fluid filling the ideal model for hydrocarbon preservation, Jianshen no.1 well Silurian gas reservoirs as one typical type, the episodic closure / open cycle type closure mechanism of interpretation of the Silurian reservoir Hanjiadian , Xiaoheba , Longmaxi unique layers of gas, the gas reservoir of the closed primarily originated in the abnormal high pressure, and high-pressure sealing ability is the film closed 7 times as many as amended in the past that the "deeply buried marine cover,highly diagenetic metamorphic and poorly closed performance," the general point of view.Based on the appearance、causes and effectiveness studies of oil and gas preservation system, the author established the structure - deposited polycyclic superimposed, multiple structural transformation in the Yangtze region oil and gas preservation system evaluation system. Based on the appearance of oil and gas preservation system, causes, effectiveness studies, the establishment of the structure - deposited polycyclic superimposed, multiple structural transformation in the Yangtze region oil and gas preservation system evaluation system.更多还原