【作者】 斯尚华；

【导师】 陈红汉；

【作者基本信息】 中国地质大学 ， 能源地质工程， 2013， 博士

【摘要】 麦盖提斜坡是塔里木盆地油气勘探的重要领域。近年来巴什托构造带油气勘探已经获得重大突破,玛南构造带玉北1井油气藏也有初步发现,但玛南构造带整体勘探成功率比较低,矛盾主要表现在玛南构造带油气成藏规律上,为此开展玛南构造带与巴什托构造带油气成藏特征对比性研究和有利勘探区带评价的研究工作,力求实现勘探的突破。本文以石油地质学和油藏地球化学理论为指导,综合运用地质、钻井、地球物理、地球化学等资料,以流体包裹体系统分析技术为主要手段,以古流体研究为切入点,开展玛南与巴什托-先把扎构造带地层发育、原油及烃源岩地球化学、断裂发育及演化、油气成藏期次及时期及成藏主控因素的研究工作,主要取得以下认识：(1)地震剖面构造解析以及构造演化分析结果表明,巴什托与玛南构造带构造差异性特征主要表现为：①巴什托断裂构造样式主要是盖层滑脱,玛南构造带主要是中浅层盖层滑脱与深层基底伸展正断裂的纵向叠加构造样式。②玛南构造带在加里东晚期—海西早期发育和田古隆起,奥陶系及志留—泥盆系遭受剥蚀；而巴什托构造带大部处于沉降阶段接受沉积,形成玛南构造带高巴什托构造带底的格局。③玛南构造带在加里东—海西早期构造变形强,巴什托构造带在海西晚期—喜山期构造变形强。④巴什托构造带构造反转发生在海西晚期,而玛南构造带发生在喜山期。(2)通过两个构造带原油与烃源岩植烷系列、甾烷系列、三环萜烷系列、碳同位素δ13C值分布曲线进行油-油、油-岩对比,以及油包裹体荧光光谱分析认为,综合判识玛南构造带玉北1井油藏的原油烃源岩为寒武系泻湖相和斜坡相两套烃源岩,有机质类型和丰度好。巴什托构造带原油烃源岩为寒武系主力烃源岩和石炭-二叠系次要烃源岩,寒武系有机质类型和丰度好,石炭-二叠系有机质类型和丰度较差。(3)结合生烃史、埋藏史,利用流体包裹体系统分析方法得出巴什托与玛南构造带成藏期次差异性特征主要表现为：①巴什托发生过两期油气运聚：第一期为早期的低成熟油充注,成藏期为海西晚期286-253Ma期间,油气充注压力19.94-21.54MPa；第二期油为高成熟油气充注,成藏期为喜山晚期18-OMa期间,油气充注压力20.43-55.70MPa。第一期油来自寒武系斜坡相岩,第二期油来白寒武系斜坡相岩和石炭-二叠系烃源岩。②玛南构造带发生过三期油气运聚：第一期为早期的低成熟油充注,成藏期为海西中期358-315Ma,油气充注压力11.23-12.88MPa；第二期油为高成熟油气充注,成藏期为海西晚期278-217Ma,油气充注压力13.63-14.78MPa；第三期油为高成熟油气充注,成藏期为喜山期21-OMa,油气充注压力20.09-61.45MPa。前两期油油源均来自下寒武统泻湖相烃源岩,第三期油油源来自寒武系斜坡相烃源岩。(4)通过分析两个构造带成藏要素及成藏特征认为：巴什托油气成藏有三套储盖组合,储集层分别为石炭系巴楚组下部东河砂岩段、石炭系巴楚组上部生屑灰岩段、石炭系小海子组灰岩,盖层为巴楚组泥岩段、卡拉沙依组中下部的膏质白云岩和膏岩段、下二叠统库普库兹满组泥岩段,现今有寒武系和石炭-二叠系多套成熟-高成熟烃源岩,油气圈闭数量多、类型好,圈闭早石炭世初具雏形,晚二叠世基本定形,烃源岩到储集层有断裂良好勾通,油气主要运移方式为垂向加侧向。玛南构造带储集层为奥陶系风化壳岩溶型储层,盖层为石炭系巴楚组泥岩段、奥陶系局部较致密的碳酸盐岩盖层,现今也有寒武系成熟-高成熟烃源岩,圈闭类型为背斜-裂缝-岩溶复合圈闭,圈闭早泥盆世已初具雏形,早二叠世完全定形,烃源岩到储集层有断裂和岩溶输导层良好勾通,油气以侧向运移为主。最后总结了两个构造带成藏主控因素为有效烃源岩、储盖层发育条件、古隆起-古斜坡的演化、岩溶储集体的发育、断层发育及沟通情况。(5)在两个构造带勘探目标优先上,运用具体问题具体分析的思路,将玛南构造带划分为麦盖提3区块中北部、麦盖提2区块北部和麦盖提1区块西北部、麦盖提1区块YB3井北部三个不同的潜在勘探区,将巴什托构造带划分为巴什托区块中北部、巴什托区块西部两个有利勘探区。针对两个构造带建立油气成藏模式,提出相应的勘探目标和勘探建议。在巴什托构造带,指出上古生界发育了有利的构造岩性圈闭并且具备良好的保存条件,而玛南构造带下古生界发育有利构造岩溶复合圈闭,是油气富集的场所。更多还原

【Abstract】 The Markit Slop is an important area for petroleum exploration in Tarim Basin. Recently, the petroleum exploration of Bashituo structural belt has achieved great breakthroughs and the reservoir of well YB1in Manan structure belt has gained a certain degree of discovery. But the success rate of the overall exploration of Manan structure belt was relatively low. The critical factor was the hydrocarbon accumulation regularity in Manan structure belt. So the comparative study of hydrocarbon accumulation characteristics and the research work for the evaluation of favorable exploration zone in Manan and Bashituo structure belt had been launched, striving to achieve breakthroughs in exploration. By using the data of geology, drilling, geophysical and geochemical and so on, this article, guided by the theory of Petroleum Geology and Reservoir Geochemistry, applied the ancient fluid as the breakthrough point and developed a research work on formation development, crude oil and source rocks geochemistry, fracture development and evolution, hydrocarbon accumulation stage and period and the favorable exploration target evaluation. The mainly achievements are as follows:(1) By studying on interpretation of the seismic profile and structural evolution, the differences of structure characteristic between the Bashituo and Manan structure belts were:①the fracture structural style of Bashituo is mostly caprock slippage, while the fracture structural style Manan is a combination of middle-shallow cap rock slippage and vertical superposition of the stretching normal fault of the deep basement.②Manan structure belt developed Hetian ancient uplift in the late Caledonian-early Hercynian with the eroding of the Ordovician and Silurian-Devonian; However, the Bashituo structure belt, which was mostly in a subsident stage, accepted deposition and formed a situation of Manan structure belt being higher than the bottom of Bashituo structure belt.③the Caledonian-early Hercynian structural deformation concentrated in Manan structure belt and the late Hercynian-Himalayan structural deformation concentrated on the Bashituo structural zone.④the structural inversion of Bashituo structural happened in late Hercynian period while the one’s of Manan’s happened in Himalayan period.(2) According to the fluorescence spectra of oil inclusions, the characteristics of Phytane series, Sterane series, Tricyclic Terpanes series, the value of carbon isotope δ13C of the oil and source rocks in these two structural belts, it is comprehensively consider that the crude hydrocarbon source rock of the reservoir of well YB1in Manan structural belt comes from two sets of hydrocarbon source rocks--Cambrian lagoon facies and slope facies and their organic matter type and abundance are well. The crude hydrocarbon source rock in Bashituo structural belt mainly comes from Cambrian source rock, whose organic type and abundance are better, and secondarily comes from permo-carboniferous source rock, whose organic type and abundance are worse.(3) By applying system analysis method of fluid inclusions, combined with the analyses of hydrocarbon generating history and burial history, the main differences of the hydrocarbon charging events between the Bashituo and Manan structural belt were:①there were two oil charging events in Bashituo structural belt:The first oil charging was the early low maturity oil charging which happened in286-253Ma in late Hercynian period and the petroleum entrapment pressure was under19.94-21.54Mpa; The second oil charging was the late high maturity oil charging which happened in18-0Ma in late Himalayan period and the petroleum entrapment pressure was under20.43-55.70Mpa. The first charging oil originated from rock slope facies in Cambrian, and the second charging oil originated from rock slope facies in Cambrian and paludal facies in carboniferous-Permian.②There were three oil charging events in Manan structural belt: The first charging oil was the early low maturity oil in358-315Ma in middle Hercynian period and the petroleum entrapment pressure was in11.23-12.88Mpa; the second charging oil was the high maturity oil charging in278-218Ma in late Hercynian period and the petroleum entrapment pressure was from13.63Mpa to14.78Mpa; the second charging oil was the high maturity oil in21-0Ma in late Himalayan period and the petroleum entrapment pressure was20.09-61.45Mpa. The first and two oil sources came from the lower Cambrian lagoon facies hydrocarbon source rocks, but the third one came from the Cambrian slope facies hydrocarbon source rocks.(4) By analyzing the two structural belt accumulation elements and accumulation characteristics, it was considered that:There existed three types of reservoir-seal assemblages in the BaShituop structural belt. The reservoir were respectively the Donghe sandstone member of Lower Carboniferous Bachu Group, bioclastic limestone member of Upper Carboniferous Bachu Group, limestone member of Carboniferous Xiaohaizi Group. The cap rocks were mudstone member of Carboniferous Bachu Group, gypsum dolomite member and gypsum member of middle-lower Kalashayi Group, mudstone member of Permian Kupukuzhiman Group, respectively. Nowadays, there are multiple sets of mature to high mature hydrocarbon source rock in the Cambrian and Permian-Carboniferous. The hydrocarbon traps, which were large in quantity and good in types, begun to take shape in Early Carboniferous and basically formed in Late Permian. These traps had a good fracture communication between the hydrocarbon source rock and the reservoir, and the petroleum trapped by them mainly migrated vertically or laterally. The type of reservoir in Manan structural belt was Ordovician weathering crust karst reservoir. The cap rocks were mudstone section of Carboniferous Bachu Group and dense carbonate rocks of Ordovician. There were a set of mature to high mature hydrocarbon source rock in Cambrian Nowadays. The trap types were a combination of anticline-crack-karst. The traps begun forming in early Devonian and finished in early Permian. The communication between the hydrocarbon source rock and reservoir was well for the good fractures and karst transport layer between them. Finally, the main controlling factors of hydrocarbon accumulation in these two structural belt are decided by an effective hydrocarbon source rocks, a well developed condition of reservoir and cap rocks, an evolution of palaeohigh-Ancient slope, the development of karst reservoir, well formed faults and their good communication..(5) On the basis of preferably predicting the exploration targets in these two structure belts, the Manan structure belt were divided into three different potential exploration areas using the method of analyzing specific issues:north-central Markit Ⅲ block, north Markit II block and northwest Markit I block, the northern part of the Markit I block YB3well. The Bashituo structure belt were divided into two favorable exploration zone of north-central Bashituo blocks and west Bashituo block. The hydrocarbon accumulation model of these two structure belts was established and then the corresponding exploration aims and proposes are put forward. It is pointed out that the favorable structural lithological traps with good storage conditions developed in Upper Paleozoic. While Manan structure belt developed traps with favorable structure karst composite which were good for petroleum accumulation in Lower Paleozoic.更多还原