【作者】 李宗亮；

【导师】 蒋有录；

【作者基本信息】 中国石油大学 ， 地质资源与地质工程， 2008， 博士

【摘要】 在国内外典型深层天然气藏成藏特征调研基础上,运用天然气成藏理论,综合运用各种基础资料,应用盆地模拟、流体包裹体分析、储层沥青分析等技术方法,对渤南-孤北地区的深层天然气成藏时间、输导体系、天然气成因判别、成藏动态过程等进行了系统分析。通过气源岩生烃史、包裹体均一温度、天然气轻烃及构造活动综合分析,明确了渤南-孤北地区深层天然气藏的形成时间和期次。研究表明,孤北潜山带存在两期不同成因天然气的充注过程:煤成气于馆陶组沉积中期充注,油型气于明化镇组沉积初期充注。渤南洼陷油型气藏存在沙一段沉积末期到东营末期和馆陶组沉积初期至今的两次充注过程,以明化镇组沉积时期至今的充注为主。成藏期受构造控制明显,构造低部位气藏形成时间早于高部位。从地质背景出发,在输导要素(断层、砂体、裂缝等)分布特征和输导机理研究的基础上,根据天然气地化资料、地层水矿化度、断层输导效率、储层沥青、生标物的变化特征等综合分析,认为不同地区、不同成因天然气的输导体系类型存在差异:渤南洼陷裂解气和孤北潜山带的煤成气主要以砂体输导为主,煤成气运移方向受构造形态控制;断阶带裂解气以断层输导为主,且同一断层不同部位输导效率存在差异。天然气成因类型判识表明,研究区存在多种来源、多种成因的天然气:孤北潜山带以石炭-二叠系煤成气为主;渤深4断阶带为油型干酪根裂解气;渤南深洼带和渤深6潜山带为原油裂解气。结合流体包裹体GOI分析表明,孤北古1井古气水界面在现今气水界面之上,表明气藏为多期充注的结果,且后期的充注量较大,保存条件较好。根据深层天然气成藏机理分析,建立了渤南地区“单源多成因多期成藏模式”和孤北地区“多源多成因多期成藏模式”。渤南地区深层气藏主要来源于同一气源即洼陷区沙四上亚段,其成因包括干酪根裂解气和原油裂解气两类,并且存在沙一末-东营末期和馆陶组沉积初期的两次充注过程;孤北地区深层气藏主要为渤南洼陷沙四上亚段的裂解气和孤北潜山带石炭-二叠系煤成气的混合成藏,以不同成因天然气的多期成藏为主,明化镇组沉积时期充注量最大。更多还原

【Abstract】 On the basis of the documentary research on the reservoir-forming characteristics of the typical deep gas reservoirs all around the world, applying theories on Gas reservoir-forming, and the combination of various radical informations, lots of techniques, such as basin modelling, high accuracy fluid inclusion testing and analysis, reservoir bitumen analysis, are fully used to analyse the reservoir-forming characteristics of Bonan-Gubei area, Jiyang Depression, including the reservoir’s formation period, hydrocarbon migration pathway, the distinguishment of the gas genetic model and the dynamic procedure of reservoir forming.Here in this paper, the formation time and stage of the deep gas reservoir are ascertained by a set of analysis techniques, including the hydrocarbon generation history, fluid inclusion homogenization temperature testing, light hydrocarbon characteristic and structure movement analysis. Subsequently, two periods of different original gas chargements consisting of coal-formed gas chargements in middle stage of Ng and oil-formed gas chargements in early stage of Nm in Gubei buried hill belt are established. At the same time, there are two accumulation periods which include from late stage of Es1 to late stage of Ed and from early stage of Ng to nowadays in oil-associated gas reservoirs in Bonan sub-sag, the accumulation of late stage of Nm plays important part, and the accumulative phase is dominated by structure apparently, the fomation period of gas reservoir at downstructure location is earlier than that of gas pool at upstructure location.From the geological setting, after studying the pattern and mechanism of migration factors which include sand bodies, faults, fractures and so on, according to the alteration characteristic of the geochemical datas of natural gas, degree of mineralization of formation water, reservoir bitumen, the fault effeciency and the biomarkers in the migration pathways, it can be easily to obtain the recognition that gas migration system categories with different genetic mechanisms and in different areas are different: cracked gas in Bonan sub-sag and coal-formed gas in GuBei buried hill migrate along sand bodies mostly, and the migration direction of the latter is dependent on structural attitude. Cracked gas in the block belt travels along the fault chiefly. In addition, the migration effectiveness in different sections of a fault is different.The origin identification of natural gas demonstrates that the region of interest has multiple sources and different origin types of gas: coal-cracked gas from Carboniferous-Permian source rocks migrates into the trap in Gubei buried hill, kerogen-cracked gas mainly appears in Boshen 4 fault blocks; and whereas oil-cracked gas dominates in deep-zone of Bonan sub-sag and Boshen 6 buried hill zone. Associated with high accuracy fluid inclusion testing and the analysis of GOI, it may be easy to get the conclusion that the palo-gas/water contact is above the present gas/water contact in well Gbg-1, which may indicate a combination of different types of gas accumulation and an increasement in the gas migration quantity in later stage,along with favourable preservation.On the foundation of deep natral gas reservoir-forming mechanism, two types of reservoir formation pattern are established respectively: one source, muti-types and polyphase reservoir-forming pattern in Bonan area and muti-sources, muti-types and polyphase reservoir -forming pattern in GuBei area. The gas making up the deep gas reservoir in Bonan sub-sag almost comes from the same source rocks in Es4s, which consists of kerogen-cracked and oil-cracked gas, and with twice chargement periods including from late stage of Es1 to late stage of Ed and from early stage of Ng to nowadays. At the same time, the deep gas reservoir in Gubei aera is composed of the gas from Es4s source rocks in Bonan sub-sag and Carboniferous-Permian gas source rocks in Gubei buried hill zone, and it has the character of different types of gas migrating into the trap at different periods, while the chargement dimention reaches maxinum in late stage of Nm.更多还原