本文预测了世界中长期油气能源需求将以低幅度增长.中国在能源发展中油气仍需保持必要的比例,认为100年来,石油地质理论经历了三个重大阶段,取得了巨大的进展.随着对油气的不断需求,石油地质学面临着一系列理论问题的挑战,从世界石油地质和勘探的发展趋势,结合我国地质和油气发展状况,提出了9个方面的石油地质理论问题,即跨若干重大构造期油气藏的形成、深层油气藏形成机制、大型油气田形成条件的有效配置、新构造运动形成的高成熟裂解气藏和生物降解为重油——沥青矿藏、未成熟原油的聚集规模、非构造油气藏聚集区带、天然气区的形成、构造与沉积对成烃与成藏全过程的具体控制和封盖层在油气聚集区对烃类相态和分布的控制等.

It is estimated that the demand for oil and gas in the world is developing at a low rate within 30 years.A necessary proportion of oil and gas in the development of energy in China should be maintained.For about 100 years,theory of petroleum geology has undergone 3 stages,and has made a great progress.With the increasing demand for petroleum,theory of petroleum geology is challenged by a series of theoretical problems.Based on the trend of development of petroleum geology.worldwide petroleum exploration,and on the geology and the development of petroleum geology in our country,9 theoretical articles are suggested,i.e.formation of oil and gas pool through many important structural stages,mechanism of formation of deep oil and gas pool,effective association of conditions for the formation of giant oil and gas pools,formation of highly thermally cracked gas pool,and that of heavy oil-bitumen deposit by microbial degradation,scale of accumulation of inmatured oil,zone(area)of nonstructural oil and gas accumulation,formation of natural gas provinces,control of geotectonics and deposition on the whole process of generation of oil and gas as well as on the formation of hydrocarbon and oil and gas pool,and control of cap rocks on the petroleum accumulation area as well as on the hydrocarbon phase and its distribution.

塔里木盆地勘探面积广阔、油气资源量大、探明程度较低，是"十四五"（2021—2025年）规划中国油气增储上产的最重要压舱石之一。塔里木盆地的勘探研究面临着诸多世界级难题，如古老海相烃源灶、超深规模储层、超深层油气赋存、超长油气藏演化等，这些因素严重制约了塔里木盆地的整体效益勘探。基于近两年的露头、钻井、地球物理、分析测试等资料，对塔里木盆地油气勘探新领域、新类型中成藏关键要素的耦合模式和资源潜力开展了系统分析。研究结果表明：塔里木盆地主要发育台盆区寒武系盐下、奥陶系、石炭系、前陆区古生界—新生界4套区域性储-盖组合及含油气系统，其中，库车坳陷白垩系亚格列木组、库车坳陷南斜坡迎烃面古生界潜山、库车坳陷北部构造带（迪北地区）侏罗系致密气断缝体、塔西南地区石炭系—二叠系、台盆区寒武系盐下台缘带及阿瓦提凹陷西缘寒武系、台盆区奥陶系断溶体是油气勘探最重要的新领域新类型。库车前陆区古生界潜山及中生界的近源油气资源量巨大，其中，温宿—佳木地区古潜山的石油资源量超过2×10⁸t、天然气资源量约为600×10⁸m³，白垩系亚格列木组的天然气资源量约为10 500×10⁸m³、石油资源量超过4 300×10⁴t，北部构造带侏罗系阿合组的天然气资源量近2.6×10¹²m³、石油资源量约为1.3×10⁸t。台盆区寒武系盐下台缘带的天然气资源量近1.8×10¹²m³；阿瓦提凹陷西缘的天然气资源量约为4 400×10⁸m³、石油资源量约为1.4×10⁸t；富满—顺北地区奥陶系断溶体的油气资源量近32×10⁸t油当量。新领域、新类型油气勘探突破带来的地质和资源潜力新认识可为后续持续高效的勘探奠定稳定基础。

Tarim Basin is characterized by vast exploration areas, large amount of oil-gas reserves, and relatively low degree of exploration. It plays a crucial role as one of the key drivers for China's domestic oil-gas reserves and production during the "14th Five-Year Plan". However, numerous world-class challenges are encountered in the exploration of Tarim Basin, such as ancient marine source rocks, ultra-deep reservoirs, the occurrence of hydrocarbons in ultra-deep reservoirs, as well as the long-term evolution of oil-gas reservoirs, which significantly limit the overall efficiency of exploration in Tarim Basin. Through an integrated approach that combines the data of outcrops, well drilling, geophysics, and testing over the past two years, this paper systematically analyzes the coupling model of key factors for the new types of hydrocarbon accumulation in new prospecting fields of Tarim Basin, as well as resource potential in the study area. The research indicates that Tarim Basin mainly developed four regional reservoir-cap combinations and hydrocarbon systems, including Cambrian pre-salt, Ordovician, and Carboniferous reservoirs in the platform area of basin, as well as the Paleozoic to Cenozoic reservoirs in the foreland area. The most important new areas and types are shown as below:the Lower Cretaceous Yageliemu Formation in Kuqa depression, the Paleozoic buried hills on the south slope of Kuqa depression, the Jurassic tight gas fault-fracture bodies in the northern tectonic belt (Dibei area) of Kuqa depression, the Carboniferous-Permian strata in the southwest Tarim Basin, the Lower Cambrian platform margin belt in platform area and the Cambrian in the west margin of Awati sag, as well as Ordovician fault-karst bodies in the platform area. The near-source oil-gas resources in the Paleozoic buried hills and the Mesozoic of Kuqa foreland basin have enormous potential. The amount of oil and gas resources can reach 2×10⁸t and 600× 10⁸m³ in the paleo buried hills of Wensu-Jiamu area, respectively. The amount of gas and oil resources in the Cretaceous Yageliemu Formation is about 10 500×10⁸m³ and 4 300×10⁴t, respectively. In the northern tectonic belt of Kuqa depression, the natural gas and oil resources of the Jurassic Ahe Formation possess 2.6×10¹²m³ and 1.3×10⁸t, respectively. The Lower Cambrian pre-salt platform margin belt in the platform area contains 1.78×10¹²m³ of natural gas. The gas and oil resources are 4 400×10⁸m³ and 1.4×10⁸t in the west margin of Awati sag, respectively. The Ordovician fault-karst bodies has around 32×10⁸t of oil equivalent in the Fuman-Shunbei area. The insights into geological and resource potential gained from breakthroughs in exploring new fields and types of oil-gas resources can lay a solid foundation for further efficient exploration in the future.

本文从震旦系灯影组灰岩普遍赋存的黑色沥青产状,类别调查入手,根据室内获得的物理化学多项信息,结合天然沥青块体的热模拟实验参数,论证了黑色沥青属石油演化的系列产物—沥青类,并对此进行了成因分类。盆地边缘尚有软沥青,地沥青分布,向盆地过渡渐变为脆沥青,黑沥青,焦沥青,盆地内分布的主要是焦沥青,与所处演化阶段吻合。威远,龙女等处所产天然气仍属热演化(降解—裂解)气,是两极分化的产物。根据区域性显示特征,对灯影灰岩油气勘探的有利地区进行了讨论,认为川西北龙门山断褶带靠盆地一侧(天井山古隆起)可望钻获液态烃,乐山—龙女寺古隆起区及川东高陡构造带,对天然气勘探有利,建议选择乐山—龙女古隆起西端的熊坡—汉王场构造带进行优先钻探。

Deepenning well Wei-Key in 1964, industrial gas flow at "Denying Limestone" Formation (Sinian) in Sichuan Basin was obtained. Since then the old aged strata have been explored continuously, and one of the large gas fields in China was discovered Afterwards, migrabitumen freguently appears in drill hole and in outcrops. This paper discusses the geological conditions and the classification of the bitumen, including various parameters such as colour, luster, configuration, density, softening point, solubility, fluorescence and (DTA), valatile carbon ratio, carbon-hydrogen elements, carbon Osotopes and so on. These data are integrated with those from thermal simulation tests to give a genetic classification of the natural bitunen, as migrabitumen soft asphaltic, asphaltic, gilsonite, grabluation, albertite, impsonite and so on. They are the products from a series of petroleum evolution. This classification is simular to Jacb's (Migtabitumen, 1985) one. From the northern boundary to the center of the basin the soft asphalt and asphalt changes gradually into grabluation, albertite and impaonite. Natural gas in the basin are considered as thermal evolution gas. It corresponds to the evolution stages and is the decomposed products of liquid hydrocarbons. It is suggested that the moderate thermal evolution area in the basin (<i>R</i>₀<4～5%) is the favorable region for natural gas exploration.

本文讨论了中国西部塔里木盆地、鄂尔多斯盆地、四川盆地三个克拉通盆地和中亚卡拉库姆盆地(及滨里海盆地)的天然气地质特点,着重讨论了这些克拉通盆地古隆起与大气田的关系,指出了太古代(及早元古代)基底的古隆起与天然气田分布的关系。认为:盆地的天然气源可能来自深部;查明盆地古隆起的分布及构造演化并厘定基底太古代(及早元古代)的时代特征及分布,对天然气勘探,特别对寻找大气田将有重大意义。

讨论了中国西部塔里木盆地、鄂尔多斯盆地、四川盆地和中亚卡拉库姆盆地的深大断裂与天然气田的关系。指出:中国西部克拉通盆地与东部裂谷盆地一样,深大断裂起了天然气运聚的通道作用;天然气可能来自深部地壳或上地幔。认为:弄清这种关系对未来大气田的勘探将有指导意义。

与国外相比，中国海相碳酸盐岩具有克拉通地块小、年代老、埋藏深、改造强等特点，面临台内、内幕、台缘与深层古老层系油气勘探潜力评价等理论技术难题。文章依托国家油气重大专项“十一五”至“十三五”碳酸盐岩项目和中国石油天然气集团有限公司碳酸盐岩储层重点实验室，围绕碳酸盐岩沉积储层开展了有针对性的理论技术攻关，取得4 项认识创新：（1）小克拉通台内普遍发育裂陷，沉积分异助推勘探领域由台缘拓展至台内；（2）发现内幕岩溶储层新类型，助推勘探领域由局部潜山区拓展至广泛的内幕区；（3）深层碳酸盐岩储层具相控性，决定储层分布的规模性和可预测性，推动勘探领域由浅层拓展至深层；（4）古老微生物碳酸盐岩具“三元”控储控分布特征，推动拓展了中—新元古界和寒武系盐下油气勘探新领域。上述理论进展填补了国内外碳酸盐岩沉积储层研究的认识空白，同时为塔里木盆地塔中、轮古、哈拉哈塘、顺北和四川盆地普光、元坝与安岳等大型油气田的发现所证实。

Different from foreign countries, the marine carbonate rocks in China are featured by development in small craton block, old geologic age, deep burial depth, and strong transformation, and the theory and technology are faced with problems in the evaluation of oil and gas exploration potential in the intraplatform, intra-carbonate strata, platform margin and old strata in deep formations. By relying on the carbonate reservoir project of national oil and gas special projects during the 11^th and 13^th Five-Year Plan periods and CNPC Key Laboratory of Carbonate Reservoirs, the targeted theoretical and technological researches on carbonate reservoir have been conducted, and innovative understanding has been achieved in four aspects, including: (1) The rifts are generally developed in the intraplatform of small cratons and the geological knowledge of sedimentary differentiation promotes the expansion of exploration field from platform margin to the intraplatform; (2) The discovery of new types of intra-carbonate karst reservoir promotes the expansion of exploration field from the local buried hill to the broad intra-carbonate strata; (3) The deep carbonate reservoir is controlled by sedimentary facies, consolidating the large&nbsp;scale and predictability of reservoir, which understanding promotes the expansion of exploration field from shallow to deep formations; (4) The geological understanding of “ternary” reservoir controlling and distribution of the ancient microbial carbonate rocks promotes the expansion of new exploration fields in the Meso-Neoproterozoic and subsalt Cambrian. The above theoretical progress supports to fill the gap in the field of carbonate reservoir study at home and abroad, and is confirmed by the discovery of large oil and gas fields such as Tazhong, Lungu, Halahatang, Shunbei in Tarim Basin, and Puguang, Yuanba, and Anyue in Sichuan Basin.<br><br>

Carbonate rocks are not only hydrocarbon reservoirs and source rocks but also cap rocks or barrier beds from hydrocarbon in Tarim Basin. Cambrian-Ordovician carbonate rocks develop in platformal and slop facies regions, in which reservoir facies belts are commonly bioclastic bank and sand bank in open platform and platform-marginal slop beak zone as well as dolomite rock flats. Good carbonate source rocks develop in Cambrian-Lower Ordovician and Middle-Upper Ordovician formations. Based on the features of hydrocarbon distribution and accumulation, the author discusses geology characteristics, formation environments of the carbonate rocks, classification of carbonate hydrocarbon reservoirs and the oil and gas exploration prospects and significant aims in the basin.

通过对鄂尔多斯盆地奥陶系沉积特征、烃源岩条件、储层类型及成藏主控因素的综合分析，认为奥陶系存在盆地中东部风化壳、古隆起周边白云岩体、台缘相带和盆地东部奥陶系盐下四大成藏区带。结合天然气勘探最新进展，优选出奥陶系岩溶风化壳作为勘探的现实目标；同时认为古隆起周边白云岩体、台缘相带及盆地东部奥陶系盐下等三大领域发育多类有效储层及圈闭，成藏潜力巨大，是盆地海相碳酸盐岩天然气勘探的接替领域。

Based on a study of the Ordovician in the Ordos Basin, such as sedimentary characteristics, conditions of source rocks, types of reservoirs and major controlling factors of hydrocarbon accumulations and traps, we could identify four provinces in Ordovician carbonates, i.e. gas reservoirs in the weathering crust of the middle and eastern basin, dolostones distributed around the Caledonian paleo-uplift, platform margin belts and the pre-salt of the eastern basin. Integrated with new advances in the gas exploration of this basin, gas reservoirs in the weathering crust were selected as preferred targets for the next gas exploration. Meanwhile, various effective reservoirs developed in dolostones circumjacent to the paleo-uplift, platform margin belts and the Ordovician pre-salt in the eastern basin were thought a great potential to serve as successive domains for the future gas exploration. This study is of great importance in guiding gas exploration in Ordovician marine carbonates of the Ordos Basin.

鄂尔多斯盆地西部余探1井在奥陶系克里摩里组缝洞体储层中获3.46&times;10⁴m³/d天然气流，通过烃源岩地球化学特征和天然气碳同位素对比分析，发现属于原生油型气，对重新认识盆地西部海相碳酸盐岩勘探领域具有极其重要的地质意义。通过对该区奥陶系古地理演化、海相烃源岩特征、储层类型及成藏模式等进行综合研究，研究表明:①盆地西部发育上、下古生界2套有效的烃源岩，下古生界海相烃源岩具备较好的生烃能力；②研究区内发育岩溶缝洞型、白云岩型、礁滩型等3种类型的储集体，储集性能较好，其中岩溶缝洞型储层和白云岩型储层分布范围广、规模较大；③盆地西部奥陶系发育上生下储和自生自储2套有效成藏组合，在西缘冲断带和天环坳陷西翼，以奥陶系内幕气藏为主，即自生自储的成藏组合，天环坳陷东翼以上生下储成藏组合为主，岩溶缝洞体气藏和白云岩气藏是下一步有利的勘探目标。

<p>Well&nbsp; Yutan-1 obtained 34 600m³/d natural gas production in the karst porous fractured reservoir of Kelimoli Formation in western Ordos Basin.According to the geochemical characteristics of source rock and a comparative analysis on carbon isotope of natural gas,it belongs to the oil type gas.This work has the extremely important geological significance for us to rediscover the marine carbonate exploration field of the western Ordos Basin.Through the analysis of the Ordovician paleogeographic evolution,the marine hydrocarbon source rock characteristics,reservoir characteristics and reservoir forming patterns in western Ordos Basin,the article concluded:(1) The western Ordos Basin develops two sets of effective hydrocarbon source rocks:Upper and Lower Paleozoic groups.The Upper Paleozoic marine hydrocarbon source rocks have good hydrocarbon generation ability.(2)This area develops karst porous fractured reservoir,dolomite reservoir and reef -type reservoir.Reservoir performance is better.The karst porous fractured reservoir and dolomite reservoir widely distributed.(3)The western basin develops two sets of effective accumulation patterns,&ldquo;upper-generation and ldown-preservation type&rdquo; and &ldquo;self-generation and self-preservation type&rdquo;.The western thrust zone and the western part of Tianhuan Sag,belong to self-generation and self-preservation type.The Eastern part of Tianhuan Sag belongs to upper-generation and down-preservation type.Karst porous fractured reservoir and dolomite reservoir are the favorable exploration target area.</p>

Being different from diagenesis of argillutite that is mainly secular compaction, the diagenesis of carbonate rock is mainly cementation and metasomatism so that carbonate rock almost lose all of primary pores and depositional water in it. The carbonate rock is in the perfectly enclosed environment of compacting fluid with deep burial. Besides of small-scaled pressure solution that is formed by deep burial and geothermal rise, other styles of diagenesis are faint. After organic matter enter the depth of hydrocarbon generation threshold, low abundance of organic matter may generate an amount of hydrocarbon but carbonate rock may not cast off such same great deal of compaction water as the argillutite. Due to neither carrier of hydrocarbon migration nor dynamics of abnormal pressure with fracture-generating condition, hydrocarbon compounds are difficult to come out from its parent rock in largescale. Hydrocarbon compounds may be dispersed in disconnected intercrystalline pores and form crystal-wrapped organic matter combined with minerals and inclusion enclave organic matter, which results in hydrocarbon percentage of carbonate rock commonly higher than that of argillutite.

塔里木盆地古生代海相地层油气资源丰富，是中国唯一一个发现大规模海相石油的盆地。虽然经历了近40年的勘探开发与科学研究，海相油气探明储量近30&#215;10⁸t，但盆地台盆区海相油气的来源问题（是来自于寒武系-下奥陶统烃源岩，还是来自于中-上奥陶统烃源岩）一直存在争议。一方面，生物标志化合物和碳、硫同位素等不同地球化学指标指示油气具多源性，在学术界产生较大争议；另一方面，地质勘探的实际规律表明，油气富集分布与油源断裂密切相关，绝大多数勘探家认为寒武系是台盆区海相油气的主力烃源岩。通过系统总结和对比塔里木盆地油气源研究的历史、争议的焦点与依据，结合近年来模拟实验数据和勘探认识，发现烃源岩的热演化差异性和各类次生作用是导致油源对比结果出现争议的关键原因，生物标志化合物、碳同位素等指标的有效性是在限定的范围内。基于芳基类异戊二烯、硫同位素、单体碳同位素等建立了油源对比的新指标，揭示了台盆区油气的主要来源是寒武系烃源岩。目前奥陶系发现的油气主要通过断穿寒武系的断裂体系运移而来。

Tarim Basin has rich oil and gas resources in the Paleozoic marine strata, and is the only basin where large-scale marine crude oil has been discovered in China. After nearly 40 years of exploration and development and scientific researches, marine oilfields with nearly 3 billion tons of reserves have been discovered. However, there have been some disputes on the source of marine oil and gas in the platform area from the source rock in the Cambrian-Lower Ordovician or the Middle-Upper Ordovician. On the one hand, based on fact that different geochemical indicators of biomarker compounds, carbon, and sulfur isotopes indicate different sources of oil and gas, great controversy has been aroused in the academic community; on the other hand, the geological exploration laws demonstrate that the enrichment and distribution of oil and gas are closely related with oil source fault, and most prospectors believe that the main source rocks are in the Cambrian strata. Based on a systematical summarization and comparison on the history of oil and gas sources in the Tarim Basin, the focus and basis of disputes, in combination with the simulation data and exploration knowledge obtained in recent years, it is found that the differences in thermal evolution and various secondary process of source rocks are the key reasons for disputes on the oil source correlation, and that the validity of the indicators such as biomarkers and carbon isotopes is within a limited range. According to aryl isoprenoid, sulfur isotope, and individual n-alkane isotope, new indicators of oil source correlation have been established, which reveal that the main source of oil and gas in the platform area is Cambrian source rocks. The Ordovician oil and gas discovered nowadays mainly migrated through the fault system of the Cambrian source rock.

明确海相烃源岩的勘探前景对于鄂尔多斯盆地下古生界勘探非常重要。鄂尔多斯盆地中东部广布的下奥陶统马家沟组碳酸盐岩动荡、富氧的古地理环境决定了其有机质丰度低、有机质类型差、生烃潜力低的先天性，不能成为有效烃源岩。盆地西、南缘广大地区呈&ldquo;L&rdquo;型连片分布的深水斜坡相中奥陶统平凉组泥页岩和泥灰岩有效烃源岩厚度80～200 m，有机质类型好（以Ⅰ型为主），有机质丰度高（&gt;02%），存在大面积中等以上烃源岩，并基本处于高、过成熟阶段，有过较高程度的生排烃过程。生烃热模拟实验表明平凉组烃源岩在演化程度达到Ro值21%时，产烃率（TOC产烃）可高达22433 kg/t，原始生烃潜力巨大，地质历史上已累计生成资源量约432亿 t 油气当量，勘探前景广阔。

The recognition of marine source rock validity is important to Lower Palaeozoic exploration in Ordos Basin. Carbonatite of lower Ordovician series is not the real source rock because of its congenital quality including low TOC, poor kerogen type, and little hydrocarbon generation potency. On the contrary, the platform slope facies that formed middle Ordovician Pingliang series is a set of fine marine source rock. Pingliang series source rock includes 80 to 200 meters mud shale and marlstone, which distributed in a large area around western and southern margin of Ordos Basin. With typeⅠkerogen and high organic content（>0.2%）, Pingliang source rock mainly belongs to above average rank, which attained high to post mature level and must have had a relatively high extent of hydrocarbon generation and expulsion history. Pyrolysis simulating experiment suggested that there have been 0.432 billion tons of hydrocarbon resource produced by Pingliang source rock in history. A perfect prospect should be expected.

鄂尔多斯盆地南缘洛南和周家河地区发育下寒武统高丰度海相烃源岩，岩性主要为页岩，局部发生了动力变质作用，为泥板岩。有机地球化学分析结果表明，该套烃源岩厚度约为0~80 m，有机碳含量（TOC）介于0.10%~13.75%之间，均值为3.32%，其中91%的样品TOC含量大于1%，52%的样品TOC含量大于2%。有机质类型以II₁型为主，部分为I型。烃源岩总体达到了较高的热演化程度，沥青等效镜质体反射率介于2.25%~2.71%之间，甲基菲比值F₁为0.46~0.60，评价为优质气源岩。尽管鄂尔多斯盆地寒武系—奥陶系时期，受到加里东和怀远运动的影响而遭受抬升剥蚀，但庆阳古隆起及以南地区寒武系—奥陶系的地层产状总体保持向南倾斜，故北秦岭—洛南地区发育的下寒武统海相烃源岩生成的油气能向庆阳古隆起方向运聚成藏。鄂尔多斯盆地南部寒武系天然气与四川盆地高磨地区寒武系油型气在同一区域，为反序列油型气。寒武系天然气中乙烷碳同位素值在鄂尔多斯盆地下古生界天然气中最低，甲烷碳同位素值与下寒武统烃源岩干酪根碳同位素值分布相似，这为揭示下寒武统烃源岩对鄂尔多斯盆地南部天然气的成藏的贡献提供了直接证据。其次，盆地南部发现的寒武系储层沥青与下寒武统烃源岩的亲缘关系则为寒武系天然气成藏的间接证据。

The marine source rocks of Lower Cambrian are mainly developed in Luonan and Zhoujiahe areas in the southern margin of Ordos Basin. The lithology of source rocks is mainly shale， with local dynamic metamorphism and argillaceous slate. The organic geochemical analysis shows that the thickness of the source rock is about 0-80 m， and the total organic carbon content （ TOC） is between 0.10% and 13.75%， with an average of 3.32%. 91% of the samples have TOC content greater than 1%， and 52% of the samples have TOC content greater than 2%. The type of organic matter is mainly type II₁， with a small amount of type I. The source rocks have experienced a high degree of thermal evolution， with equivalent vitrinite reflectance of 2.25% - 2.71% and the methylphenanthrene ratio （F₁） between 0.46 and 0.60. The overall evaluation is high quality gas source rocks. Although the Cambrian-Ordovician was uplifted and eroded by the Caledonian and Huaiyuan Movements in the Ordos Basin， the Cambrian-Ordovician strata in the Qingyang paleo-uplift and the area to the south remained generally inclined to the south， the oil and gas generated from the Lower Cambrian marine source rocks developed in the North Qinling-Luonan area can migrate and accumulate in the direction of the Qingyang paleo-uplift. The characteristics of Cambrian natural gas in the south of Ordos Basin are similar to those in Gaomo area of Sichuan Basin， and they are both carbon isotope reverse sequence oil type gas. The carbon isotope of ethane from Cambrian natural gas is the lightest in the Lower Paleozoic， and the carbon isotope distribution of methane is similar to that of kerogen in the Lower Cambrian source rocks. There are direct evidences that the Lower Cambrian source rocks have contributed to the hydrocarbon accumulation of natural gas in the southern Ordos Basin. Besides， the relationship between Cambrian reservoir bitumen and Lower Cambrian source rocks in the south of the basin is the indirect evidence of the Cambrian gas accumulation in the south of the basin.

通过不同类型烃源岩生排烃模拟实验与不同源储组合实际剖面研究，确定不同类型烃源岩在不同地质背景下的排油率，基于源内、源外分散液态烃和古油藏裂解成气时机及其影响因素研究，明确油裂解型气源灶的主生气期，在此基础上，建立以成因法为基础的分散液态烃裂解气定量评价“五步法”。不同类型烃源岩生排烃模拟实验、不同源储配置排油率研究与岩石热解参数分析等均反映烃源岩内存在数量相当可观的滞留液态烃，总体特征为有机质含量越低，排油率越小。有机碳含量小于2%的烃源岩，液态窗阶段排油率多小于50%；有机碳含量为2%～4%的砂泥互层和厚层泥岩排油率分别为60%和30%。从烃源岩排出的液态烃受古地形控制，以不同丰度差异聚集在地层中，呈分散或半聚半散形式赋存，统称为源外分散液态烃。源内和源外分散液态烃进一步深埋后，均可裂解形成常规和非常规天然气。四川和塔里木盆地勘探实践证明，分散型、半聚半散型和聚集型液态烃裂解气是中国深层天然气的重要来源，勘探地位十分重要。图13表4参40

Oil expulsion rate of different types of source rock in geologic settings are estimated by modeling hydrocarbon generation and expulsion and examining the geological sections of different source-reservoir combinations. The major gas generation peak of oil-cracked gas kitchen is determined by study on the gas generation timing of dispersed liquid hydrocarbon inside and outside source rock and ancient oil reservoirs, and the factors affecting the gas generation timing. A “five-step method” based on the origin method is set up to quantitatively evaluate the cracked gas generated by dispersed liquid hydrocarbons. The hydrocarbon generation and expulsion experiment of different types of source rock, the study on oil expulsion rate of different source-reservoir combinations, analysis of rock pyrolysis parameters of reservoir rock all show that there is a large amount of liquid hydrocarbons retained in the source rock, and the feature on the whole is the oil expulsion rate decreases with the reducing of total organic carbon (TOC). The expulsion rate of source rock with TOC of less than 2% is below 50% in general during the liquid-window stage, while that of alternating sandstone and mudstone and of thick mudstone, with TOC of 2%?4%, are 60% and 30% respectively. Affected by the ancient landform, the expelled liquid hydrocarbons accumulated in different abundance in formations, with dispersed or semi-dispersed and semi-gathered form, and they are called dispersed liquid hydrocarbons outside source rock. When buried deeper, both dispersed liquid hydrocarbons inside and outside the source can be cracked into natural gas to form conventional and unconventional gas accumulations. Exploration practices in the Sichuan and Tarim basins have proven that the cracked gas generated by dispersed, semi-dispersed and semi-accumulated, and accumulated liquid hydrocarbons is an important source of deep natural gas in China, and takes an important position in gas exploration.

中国南方地区寒武系筇竹寺组和奥陶系五峰组—志留系龙马溪组均发育一套富有机质页岩,但页岩气钻探效果差别极大,开展成藏差异比较研究具有理论和现实意义。研究认为：①四川盆地五峰组—龙马溪组TOC值比筇竹寺组略高,盆地外围地区筇竹寺组TOC存在高值区;②筇竹寺组热演化程度较五峰组—龙马溪组明显偏高;③筇竹寺组有机质孔隙不发育,孔隙度是五峰组—龙马溪组的1/3~1/2;④筇竹寺组含气量低,仅为五峰组—龙马溪组的1/2;⑤筇竹寺组以硅质页岩为主,五峰组—龙马溪组以钙质、钙质硅质页岩为主,硅质成因不同;⑥五峰组—龙马溪组普遍超压,筇竹寺组以常压为主。这种差异形成的原因在于：①沉积环境不同,影响TOC值和页岩厚度;②筇竹寺组热演化程度过高,导致生烃衰竭、有机质炭化、孔隙度降低,含气性变差;③筇竹寺组顶底板封闭条件较差,影响页岩气保存;④构造位置不同,五峰组—龙马溪组处于斜坡和向斜区,具超压,有利于页岩气保存;⑤筇竹寺组放射性铀含量约为五峰组—龙马溪组的2倍,是热演化程度高的重要原因。从而提出南方海相经济性页岩气富集需具备有利的地质条件（富有机质集中段发育,热演化程度适中,有机质孔隙发育,含气量高,顶底板保存条件良好,埋深适中）,其中五峰组—龙马溪组页岩气成藏条件有利、资源经济性好,筇竹寺组成藏条件总体较差、有利区范围有限。图10表5参49

Organic-rich marine shales are developed in both the Cambrian Qiongzhusi Formation and the Ordovician Wufeng Formation-Silurian Longmaxi Formation in South China, but are different in the drilling results of shale gas exploration. Comparing the differences in shale gas formation conditions between Qiongzhusi and Wufeng-Longmaxi has practical and theoretical significance. This study reveals: (1) in the Sichuan Basin, the Wufeng-Longmaxi Formation has slightly higher TOC than the Qiongzhusi Formation, whereas Qiongzhusi Formation has some local high TOC areas outside of the Sichuan Basin; (2) the Qiongzhusi Formation has much higher thermal evolution degree than the Wufeng-Longmaxi Formation; (3) with undeveloped organic pores, the Qiongzhusi Formation has a 1/3 to 1/2 porosity of the Wufeng-Longmaxi Formation; (4) Qiongzhusi shale has a lower gas content, only 1/2 of that in Wufeng- Longmaxi shale; (5) the Qiongzhusi Formation is mainly composed of siliceous shale and the silica is hot water origin, whereas the Wufeng-Longmaxi Formation consists mainly of calcareous siliceous shale and the silica is biogenic origin; (6) the Wufeng-Longmaxi Formation has overpressure, while the Qiongzhusi Formation is normal in pressure. The reasons for the differences are: (1) different sedimentary environments affect TOC and shale thickness; (2) the Qiongzhusi Formation is over-mature, which caused depletion of hydrocarbon generation, organic carbonization, porosity reduction, and gas content drop; (3) the bad roof and floor conditions of the Qiongzhusi Formation are not good for shale gas preservation; (4) Wufeng-Longmaxi Formation is located in the slope and syncline accompanied with overpressure, and is in favor of preservation and high production of shale gas; (5) the uranium content in the Qiongzhusi Formation is twice that of the Wufeng-Longmaxi Formation, which is the main reason of its higher thermal evolution degree. It is concluded that shale gas enrichment in the marine shale in South China requires favorable geological conditions: organic-rich intervals, moderate thermal evolution, rich organic pores, high gas content, good roof and floor preservation conditions, and moderate burial depth. The Wufeng-Longmaxi Formation has better shale gas enrichment conditions and higher resource potential, whereas the Qiongzhusi Formation has poorer shale gas accumulation conditions and limited favorable areas.

近年来，在塔里木、四川、鄂尔多斯三大盆地海相碳酸盐岩层系中相继发现了一批以地层-岩性油气藏为主体的大油气田，虽然单个油气藏储量丰度低，但由于油气藏呈集群式分布，因此总体油气储量规模大。为了揭示海相碳酸盐岩大油气田形成条件和分布规律，本文从盆地的构造演化、烃源灶的分布范围、有效储层的发育条件以及油气成藏模式等方面，来分析和探讨中国三大克拉通盆地海相碳酸盐岩层系油气藏大型化成藏条件与特征。研究表明，大范围分布的烃源灶及其晚期规模生烃是大油气田形成的资源基础;大面积呈似层状分布的礁滩体及受不整合面控制的岩溶储集体为大油气田的形成提供了有效储集空间;&ldquo;退火&rdquo;地温场与递进埋深的耦合是大范围油气成藏的重要机制;下侵式、扬程式、转接式成藏模式是油气大范围成藏的重要途径。古隆起及其斜坡带、台缘带礁滩体、与蒸发岩共生的台内滩、深大断裂带具备形成碳酸盐岩大油气田地质条件，是油气勘探的有利区带。

In recent years, a series of large oil-gas fields dominated by stratigraphic-lithological reservoirs have been found in marine carbonate reservoirs in three large onshore basins in China, i.e., Tarim Basin, Sichuan Basin, and Ordos Basin. Despite low abundance of reserves in each of these oil-gas reservoirs, their overall scale is large due to cluster distribution. In order to reveal accumulation factors and distribution patterns of large-scale oil-gas fields in marine carbonate reservoirs, this study analyzed and discussed large-scale hydrocarbon accumulation factors and characteristics of marine carbonate reservoirs in the three large cratonic basins from four aspects: (1) tectonic evolution of cratonic basin; (2) distribution of hydrocarbon source kitchen; (3) development conditions of effective reservoirs; and (4) model of hydrocarbon accumulation. Results show that widely distributed hydrocarbon kitchens and their late large-scale accumulation are resource base of large oil-gas fields. A large area of reefs and shoals in stratoid distribution and karst reservoirs controlled by unconformity surface provide effective reservoir space for formation of large oil-gas fields. Coupling of annealing geothermal field and progressive burial is an important mechanism of large-scale hydrocarbon accumulation in marine carbonate reservoirs in the cratonic basins. Downward invasion model, lift model, and switching model are important pathways for petroleum accumulation. This study indicates that palaeouplifts and associated slope zones, reefs and shoals in platform margin zone, intra-platform shoals symbiotic with evaporites, and deep faults meet geological conditions for large-scale oil-gas field formation in carbonate reservoirs, and thus are favorable zones for oil-gas exploration.

塔里木盆地超深层海相碳酸盐岩油气资源丰富，已发现中国最大的风化壳型油田和最大的凝析气田，但勘探开发长期局限在古隆起及斜坡部位。近年来，随着勘探上突破"古隆起控油、斜坡富集"的传统理论认识以及地震、钻井与开发配套技术进步，在坳陷区发现了超深层（大于7 500 m）走滑断裂断控型油田——富满油田。富满油田的勘探开发实践与研究表明：（1）走滑断裂的发育不仅沟通了深层下寒武统烃源岩，而且控制了中奥陶统碳酸盐岩缝洞体储层的发育，并与上奥陶统巨厚泥岩构成了优越的走滑断裂断控型油气成藏体系；（2）油气沿走滑断裂破碎带呈条带状差异分布，具有圈闭类型特殊、油柱高度大、油品性质好、单井产量高等特点；（3）发现三级石油地质储量达4&#215;10⁸t，石油资源量达10&#215;10⁸t，开发高效井多，快速建成了原油产量达160&#215;10⁴t/a的产能。通过持续攻关，逐步形成了沙漠区超深层高密度宽方位三维地震采集、弱走滑断裂刻画、碳酸盐岩破碎带圈闭评价、高效井位部署、超深层钻完井等配套技术，支撑了超深层复杂断控型碳酸盐岩油藏的规模与效益勘探开发。

Tarim Basin has enriched oil and gas resources in ultra-deep marine carbonate rocks, where China's largest weathering crust-type oil reservoir and largest condensate gas reservoir have been discovered. However, the oil and gas exploration and development have been conducted only in palaeohighs and slopes for a long time. In recent years, with breakthroughs in the traditional theoretical understanding of "oil accumulation controlled by palaeohighs and enrichment in slopes" and advances in the supporting technologies of seismic exploration, drilling and development, Fuman oilfield, the ultra-deep (over 7 500 m) strike-slip fault-controlling oilfield, has been discovered in the depression area. Exploration and development practice and studies of the Fuman oilfield show the following results. First, the developed strike-slip faults not only cut through the deep Lower Cambrian source rocks, but also control the development of Middle Ordovician carbonate cavity-fracture reservoirs, and constitute a superior petroleum accumulation system under the control of strike-slip faults together with the huge thick Upper Ordovician mudstone. Second, the oil and gas show a stripe-shaped differential distribution along the strike-slip fractured zone, characterized by special trap type, large oil column height, good oil property, and high single-well production. Third, the predicted geological reserves of oil are up to 4&#215;10⁸t, the amount of oil resources is 10&#215;10⁸t, and there are many efficient development wells. The oil productivity of 160&#215;10⁴t/a has been rapidly achieved. Through continuous research, the supporting technologies such as ultra-deep, high-density and wide-azimuth 3D seismic acquisition, characterization of weak strike-slip faults, evaluation of traps in carbonate fractured zone, efficient well location deployment, ultra-deep drilling and completions have been gradually established in the desert area, providing supports for the large-scale and efficient exploration and development of the ultra-deep complex fault-controlling carbonate reservoirs.

以塔里木盆地和四川盆地多层段发育的礁滩体解剖为例，研究不同类型礁滩储集层孔隙成因和非均质性，分析其有效储集层分布规律。礁滩储集层可分为生物礁和颗粒滩两大类：前者与生物格架有关，多形成镶边台缘，可细分为台缘生物礁和台内生物礁储集层；后者与生物格架无关，在缓坡型碳酸盐台地多受海平面升降控制，由滩体迁移形成广布的颗粒滩，在陡坡环境有台缘颗粒滩和台内颗粒滩之分。礁滩体储集空间主要形成于同生期和埋藏期两个阶段，同生期孔隙受原岩骨架和与层序界面有关的溶蚀作用控制，而埋藏期孔隙发育和分布则与同生期孔隙发育和分布密切相关，具有继承性。礁滩储集层具强烈非均质性，有效储集层分布比较复杂，对礁体而言，向上变浅旋回顶部的台缘礁和与礁共生的生物滩是孔隙发育主体，独立滩体向上变浅旋回顶部发育的颗粒滩也是孔隙发育主体，且与致密层间互分布。总体而言，颗粒滩储集层规模大于且物性好于生物礁储集层。图11表2参29

Taking reef-shoal bodies developed in multiple formations in the Tarim Basin and Sichuan Basin as examples, this paper examines the origin of pores and heterogeneity of types of reef-shoal reservoirs, and tries to find out the distribution rules of various reef-shoal reservoirs. Reef-shoal reservoirs can be classified into two main types, i.e. biohermal reservoirs and grain shoal reservoirs. The former, related to reef framework, in the form of frilled platform margin, can be subdivided into interior platform reef complex and margin reef complex (sedimentary or tectonic origin). The latter, not related to reef framework, is controlled by the fluctuation of sea level on gentle slope carbonate platform, is widely developed on carbonate ramp due to the migration of shoal, and can be subdivided into interior platform shoal and platform-margin shoal on steep slopes. Reservoir space of reef-shoal carbonates was primarily formed during syngenetic and burial stages. Syngenetic porosity is controlled by original rock fabric and dissolution related to the exposure of sequence boundaries, while porosity development and distribution in burial stage is closely related to that in syngenetic stage, showing inherited features. Reef-shoal reservoirs are strongly heterogeneous, and complicated in effective reservoir distribution. Platform margin reef and biohermal shoal coexisting with reef on the top of shallowing upward sequence are main reservoirs rich in pores, the grain shoal deposited on top of shallowing upward cycle of isolated reef is also the main zone rich in pores, which usually interbeds with tight reservoir. Overall, grain shoal reservoirs are bigger in scale and better in physical properties than biohermal reservoirs.

四川盆地高石梯东部地区上震旦统灯影组微生物碳酸盐岩是重要的天然气产层。结合区域地质研究，通过岩心观察、镜下鉴定，对研究区微生物碳酸盐岩岩石学、成岩作用类型及序列展开系统研究，明确了储集空间特征，探讨了储层发育主控因素。上震旦统灯影组微生物碳酸盐岩以白云岩为主，岩石类型主要包括叠层石、球粒岩、凝块石和泡沫绵层白云岩。微生物白云岩储层主要发育于灯四上段、灯四下段和灯二段，储集空间类型以发育窗格孔、空腔溶洞、粒间溶孔、晶间溶孔和铸模孔为特征，优质储层段孔隙度一般在1%~6%之间，渗透率一般小于1&times;10-3&mu;m2。微生物白云岩储层发育的控制因素主要包括原始岩石类型和成岩作用。原始沉积岩石中的微生物结构决定了储层的储集空间类型和孔隙结构特征；成岩作用是储层是否发育的关键因素，建设性成岩作用包括早期微生物白云石化作用、埋藏溶蚀作用与岩溶作用；破坏性成岩作用主要包括过度白云石化作用和硅化作用。

<p>Based on regional geology,core description and thin section observation,the petrology and reservoir properties of the microbial carbonates of Upper Sinian Dengying Formation (Z₂<em>dn</em>) in eastern Gaoshiti area in the Sichuan Basin are investigated in detail.The origin of the microbial dolostone is analyzed briefly.Dolostones dominate in microbial carbonate rocks of Dengying Formation and the lithology include stromatolite,spherulite,thrombolite and spongy layered dolomite.Microbial dolostone reservoirs are mainly developed in both the upper & lower parts of Z₂<em>dn</em>₄,and in&nbsp;Z₂<em>dn</em>₂.The reservoir space is composed of fenestral pores,skeleton cavities,inter-particle dissolution pores,inter-crystal dissolution pores and moldic pores.The good reservoirs mostly have a porosity range of 1% to 6% and permeability of less than 1&times;10^-3&mu;m².The formation and distribution of the microbial dolomite reservoirs are jointly controlled by the original rock type and digenesis.Different microbial textures in the originally deposited rocks determined the types of reservoir space and pore structure.Diagenesis is a key factor for development of microbial reservoirs.The constructive diagenesis for forming good reservoirs are early microbial dolomitization,karst,and burial dissolution;while the destructive diagenesis are over-dolomitization and intense silicification.</p>

中国叠合盆地超深层油气资源丰富,是重要的战略接替领域。勘探研究与实践揭示,超深层油气成藏条件具有两分性:有利成藏条件只存在于特定的盆地环境,具有地域性;不利成藏条件是超深层固有属性,具有普遍性。烃源灶有效且有规模、储集层至今保持有效储集性能且有规模、生-储-盖要素存在空间组合且至今保持有效性是超深层是否具有勘探价值的决定性要素。有利于超深层具备勘探潜力的盆地具有以下特征:①存在克拉通差异沉降演化,且在漫长地质历史时期未被深埋,烃源灶发育且至今仍在有效生烃窗口;②发育碳酸盐岩为主的沉积层系,存在颗粒型台缘和台内滩并经过建设性成岩作用改造,或者在地质历史时期曾经历地下 水溶蚀淋滤,使超深层孔隙(含裂缝、溶洞)发育的储层至今依然有效;③碎屑岩、基岩或火山岩储层发育需要满足长期浅埋+ 后期深埋且深埋时间不长、存在构造桥的托举作用、较少压实作用影响、构造作用产生裂缝或长期风化作用建设性改造结晶岩类等单一要素或多种要素组合作用;④盆地总体呈中—低地温场,或烃源岩发育阶段环境中无过量放射性物质存在,规模生烃过程不被速化。不利于超深层成藏的原因有:①机械压实和高温高压导致超深层成岩作用强、岩石颗粒塑性增加,不利于储层孔隙空间的保存;②超深层因埋藏深、埋藏历史长,多数烃源岩已经失去生烃能力,烃源灶有效性受限;③形成生-储-盖-圈有效组合的机会偏少,且有经济性的资源成矿几率降低。中国超深层油气资源丰富,勘探潜力大,但规模勘探面临着成藏理论有待完善、工程技术有待提高等挑战,亟待开展攻关研究。

The ultra-deep oil and gas resources are abundant in China’s superimposed basins, which are an important strategic replacement field. The exploration and research work has revealed that there is a dichotomy of accumulation conditions for ultra-deep oil and gas reservoirs; favorable accumulation conditions only exist in specific basin environments, characterized with regionality, while the unfavorable accumulation conditions are inherent attributes of ultra-deep layers, characterized with universality. The decisive factors determining whether ultra-deep layers have exploration value are the effectiveness and scale of source kitchens, the effective reservoir and its scale, as well as the spatial combination and effectiveness of source, reservoir, and cap. The basins with exploration potential in ultra-deep layers have the following characteristics: (1) there is differential subsidence evolution in cratons, which have not been deeply buried during a long geological history, and where source kitchens are developed and still in an effective hydrocarbon-generation window to this day; (2) sedimentary strata mainly composed of carbonate rocks are developed, with granular platform marginal-platform shoals and intraplatform shoals, and have undergone constructive diagenesis and modification, or have experienced groundwater dissolution and leaching during geological history, as result of which reservoirs with pores in ultra-deep layers (including fractures and caves) are developed and have been effective till today; (3) the development of clastic rock, basement, or volcanic reservoirs requires a combination of single or multiple factors, such as long-term shallow burial and later deep burial with a short burial time, the presence of structural bridges for supporting effect, less compaction, the generation of fractures by tectonism, or long-term weathering for constructive reformation of crystalline rocks; (4) the basin generally presents a medium to low geothermal field, or there is no excessive radioactive material in the environment during the development of source rock, and the large-scale hydrocarbon generation is not accelerated. The reasons for the occurrence of unfavorable accumulation conditions in ultra-deep layers include: (1) mechanical compaction and high temperature and pressure result in strong diagenesis and increased plasticity of rock particles in ultra-deep layers, which is not favorable to the preservation of reservoir pore space; (2) most source rocks in ultra-deep layers have lost their hydrocarbon-generation potential, and the effectiveness of source kitchens is limited due to deep burial and long burial history; (3) there is a low probability for forming an effective combination of source-reservoir-seal-trap, and the probability of economic resource mineralization is reduced. China has abundant oil and gas resources and great exploration potential in ultra-deep layers, but large-scale exploration faces challenges in terms of the hydrocarbon accumulation theory to be perfected and engineering technology, and it is urgent to carry out researches to achieve relevant breakthroughs.

塔里木盆地寒武系盐下具备形成复式大油气区的成藏条件，是勘探程度最低、勘探潜力最大的战略接替领域。但多年的勘探一直未取得重大突破，关键问题是由于生烃中心、规模性滩体储层控制因素及空间展布不清而导致有利勘探方向和区带不明。鉴于此，综合应用地震和钻井、测井、录井及地球化学等资料，开展寒武系盐下控源、控储、控盖和控藏研究，构建寒武系盐下领域控藏模式，明确有利区带和勘探突破方向。取得了以下几点认识：①古裂谷控制生烃中心。南华系—震旦系形成的断坳结构为下寒武统的发育提供了构造背景，控制了寒武系玉尔吐斯组的沉积，在裂谷控制的负向构造区玉尔吐斯组厚度大，形成生烃中心。②古隆起控制滩相白云岩储层。与南华纪古裂谷同时形成的古隆起控制了肖尔布拉克组高能滩的发育与分布，塔南古隆起南北两侧形成规模性白云岩滩相储层。③古坳陷控制膏盐岩盖层发育。在中晚寒武世由于轮台—古城近南北向镶边台缘的发育造成塔西台地封闭从而形成强烈的蒸发环境，在统一的台内坳陷沉积了广覆式膏盐岩盖层。④“裂—隆—坳”格架控制生储盖时空匹配及油气分布。构建了稳定型“裂—隆—坳”、活动型“裂—隆—坳”、过渡型“裂—隆—坳”3种控藏模式，指出稳定型和过渡型地区是寻找寒武系盐下大气藏的主要勘探方向，明确阿瓦提凹陷和满西凹陷之间的阿满低隆起是寒武系盐下大气田勘探的首选目标区。

The Cambrian pre-salt had the accumulation conditions for compound large reservoir， and was the strategic replacement area with the lowest exploration degree and the largest exploration potential in Tarim Basin. However， no significant discoveries have been made in the exploration for many years， the key problem is that the unclear of controlling and space distribution of hydrocarbon generation center and scale beach reservoir result in the ambiguity of favorable exploration directions and zones. In view of this， comprehensive application of seismic， drilling， well-logging， mud-logging and geochemical data has been carried out to study the source controlling， reservoir controlling， cap control and reservoir controlling of the Cambrian subsalt area， constructing the reservoir controlling model and defining the favorable zones and exploration breakthrough direction. The following points have been gained： （1）The paleo-rifts controlled hydrocarbon generation center. The rift depression formed in Nanhua System to Sinian System provided the structural background for the development of the Early Cambrian， and controlled the deposition of the Cambrian Yuertusi Formation. In the negative tectonic area， the thickness of Yuertusi Formation was large and formed the hydrocarbon generating center. （2）The paleo-uplift controlled the development of beach facies dolomite reservoir. The paleo-uplift formed at the same time with Nanhua System paleo-rift controlled the development and distribution of high energy beach in Xiaerbulake Formation， and large-scale dolomitic shoal facies reservoirs were formed on both sides of the Tanan paleo-uplift. （3） The paleo-depression controlled the distribution of gypsum-salt rock cap. In the Middle and Late Cambrian， due to the development of the near north-south edge platform margin， the Taxi platform was closed and formed a strong evaporation environment， and a wide covering paste rock cap was deposited in the unified depression within the platform. （4）The matching of rift-uplift-depression controlled the formation and distribution of oil and gas. Three types of reservoir-controlling models which were stable rift-uplift-depression， active rift-uplift-depression and transitional rift-uplift-depression were established， besides， indicated the stable and transitional areas were the main exploration directions， and the Aman low uplift between Awati Sag and Manxi Sag was the preferred target area.

四川盆地晚二叠世经历了克拉通内裂陷作用以及基底断裂活动，在区域大缓坡背景下，形成&ldquo;三隆三凹&rdquo;的古地理格局，发育鄂西&mdash;城口海槽、开江&mdash;梁平海槽以及盐亭&mdash;潼南海槽。在区域背景及动力学分析的基础上，利用钻井、露头、地震资料等论证了盐亭&mdash;潼南海槽的几何形态，盐亭&mdash;潼南海槽发育在川中地区，整体呈北西南东向近平行于开江&mdash;梁平海槽展布，向西北部广海开口，向东南台地区逐渐变浅并与鄂西&mdash;城口海槽连通。利用地震、地质结合的方法，探讨了盐亭&mdash;潼南海槽的沉积格局，其以细粒沉积为主，地层厚度薄，其西侧磨溪&mdash;中江台缘带以发育生屑滩为主，东侧广安&mdash;公山庙台缘带以发育生物礁为主；生物礁滩的分布随着海平面变化具有明显的迁移特征，整体上可以分为两期，并逐渐由两侧台缘带向海槽内迁移。盐亭&mdash;潼南海槽的形成、发展及消亡主要受勉略洋扩张收缩的影响；晚二叠世勉略洋扩张期，四川盆地NW向基底断裂活动，导致川中地区正断活动，形成断陷海槽，即盐亭&mdash;潼南海槽。

<p>Previous research shows that Sichuan Basin underwent intracratonic rift and basement fault activities in the Late Permian, developing a paleogeographic framework of &ldquo;three uplifts and three depressions&rdquo; under the background of the regional large ramp, including ExiChengkou trough, KaijiangLiangping trough and YantingTongnan trough. Based on geological background and tectonic dynamics analysis and using data of drillings, outcrops and seismos, YantingTongnan trough has been researched in Central Sichuan Basin in our study, which extends in NWSE nearly paralleling to KaijiangLiangping trough, opening to the sea northwestward, and gradually becoming shallower to the east platform and conneted to ExiChengkou trough. According to the comprehensive analysis of geology and seismism, sedimentary configuration of YantingTongnan trough has been discussed, which mainly filled with fine grained sediment, and platform margin reef belt distributes around the trough. Organic banks distribute on the west margin of the trough and reefs on the east margin of the trough. The formation, evolution, filling and extinction processes of the YantingTongnan trough was controlled by the expansion of Mianl&uuml;e ancient ocean; in the extensional tectonic environment, due to Emei Taphrogenesis, the NW basement faulting inside Sichuan Basin caused tensoshear activities and thus resulted in tectonic differential settlement of cratonic basin and a series of uplifts and troughs.</p>

基于四川盆地海相大中型气田基本特征分析,结合海相克拉通阶段主要成藏地质单元划分及其对关键成藏要素的控制作用研究,探讨盆地海相碳酸盐岩大中型气田分布规律,指出勘探方向。通过周期性拉张-隆升背景的分析,提出四川海相克拉通阶段发育形成了5个大型古裂陷、3个大型古隆起、5个大型古侵蚀面等大型地质单元,这些地质单元控制了大中型气田的关键成藏要素：①大型古裂陷控制了优质烃源岩生烃中心展布;②大型古裂陷边缘、古隆起高部位、古侵蚀面控制了优质储集层的展布;③大型古裂陷、古隆起、古侵蚀面和现今构造背景联合控制了多类大中型圈闭的形成;④大型地质单元内圈闭继承性演化控制天然气规模聚集。通过大中型气田展布特征与大型成藏地质单元的对比分析,提出单个或多个成藏地质单元与现今构造的叠合关系控制了大中型气田的分布,&#x0201c;三古&#x0201d;叠合区最为有利。德阳&#x02014;安岳古裂陷周缘、龙门山古裂陷东缘、开江&#x02014;梁平海槽及城口&#x02014;鄂西海槽边缘带、环川中水下古隆起高部位、川东&#x02014;蜀南地区茅口组顶界古侵蚀面、川中&#x02014;川西雷口坡组顶界古侵蚀面等,是四川盆地海相碳酸盐岩大中型气田勘探主要领域和方向。图6表2参59

Based on the analysis of the basic characteristics of medium- and large-sized marine gas fields in Sichuan Basin, combined with the division of major reservoir forming geological units in the marine craton stage and their control on key hydrocarbon accumulation factors, the distribution law of medium- and large-sized marine carbonate gas fields in the basin was examined and the exploration direction was pointed out. Through the analysis of the periodic stretching-uplifting background, it is concluded that five large scale paleo-rifts, three large scale paleo-uplifts, five large scale paleo erosion surfaces were formed in the marine craton stage of Sichuan Basin, and these geological units control the key reservoir forming factors of medium and large sized gas fields: (1) Large-scale paleo-rifts control the distribution of high-quality hydrocarbon generation centers. (2) The margin of large-scale paleo-rifts, high position of paleo-uplifts and paleo erosion surfaces control the distribution of high-quality reservoirs. (3) Large-scale paleo-rifts, paleo-uplifts, paleo erosion surfaces and present tectonic setting jointly control the formation of many types of large and medium-sized traps. (4) Natural gas accumulation is controlled by the inheritance evolution of traps in large geological units. Based on the comparative analysis of the distribution characteristics of medium- and large-sized gas fields and large geological units, it is proposed that the superimposition relationship between single or multiple geological units and the present structure controls the distribution of medium- and large-sized gas fields, and the "three paleo" superimposed area is the most advantageous. According to the above rules, the main exploration fields and directions of medium- and large-sized marine carbonate gas fields in Sichuan Basin include periphery of Deyang-Anyue paleo-rift, eastern margin of Longmenshan paleo-rift, margins of Kaijiang-Liangping oceanic trough and Chengkou-western Hubei oceanic trough, the high part of the subaqueous paleo-uplifts around Central Sichuan, paleo erosion surfaces of the top boundary of Maokou Formation in eastern and southern Sichuan Basin, paleo erosion surfaces of the top boundary of the Leikoupo Formation in central and western Sichuan Basin.

蒂索生烃模式指出了“液态窗”存在的温度和深度范围，成为油气勘探的“黄金带”，但勘探实践证实中国叠合盆地发育多个勘探“黄金带”。多勘探“黄金带”的形成有3方面因素：①烃源灶多期、多阶段发育与古老烃源岩“双峰式”生烃；②储集层多阶段发育；③成藏多期性与晚期有效性。常规烃源灶、液态烃裂解气源灶以及多套规模有效储集层控制了“黄金带”的时空分布；勘探“黄金带”具有继承叠置与横向迁延的特点，其中古隆起、古斜坡、古台缘与多期继承性断裂带控制了勘探“黄金带”内油气分布。多勘探“黄金带”的提出是对中国近年来油气发现规律认识的深化，表明中国叠合盆地深层仍有经济资源，油气发现呈多期、多阶段的特点，勘探潜力更大。图10表1参20

The hydrocarbon generation model proposed by Tissot et al. points out the temperature and depth of “liquid HC window”, which has become a “golden zone” for hydrocarbon exploration. It has been proved by exploration that multi-staged “golden zones” for hydrocarbon exploration is commonly developed in the superimposed petroliferous basins of onshore China. There are three factors for the formation of multi-staged “golden zones” of HC exploration in the superimposed basins: (1) source kitchens developed with multi-periods and multi-centers which have been verified to lead multi-stages of HC generation with large scale, (2) multi-staged reservoirs develop with large scale, (3) hydrocarbon accumulations occur with the multi-periods and late effectiveness. The conventional source kitchens, dispersed liquid HC-cracking gas kitchens and effective reservoirs with large scale join together to control the distribution of “golden zones” in timing and space. Explorational “golden zones” have the characteristics of inherited stacking and lateral variation. Palaeo-highs, palaeo-slopes, palaeo-platform margins, and multi-period inherited fault zones control the distribution of hydrocarbons in the explorational “golden zones”. The concept of multi explorational “golden zones” helps to deepen the knowledge of new hydrocarbon distributional regularity which revealed recently in China. It shows that there exist economic resources in the deep section of the superimposed basins of onshore China. The hydrocarbon discovery history in the superimposed petroliferous basins has the feature of multi-peaks of proven reserve increase and lasting a quite long period, which indicates a huge potential for future exploration.

Reef-bank of Sichuan (四川) basin have been explored along the platform margin belt on both sides of the Kaijiang (开江)-Liangping (梁平) trough for a long time. Correspondingly, a series of major breakthroughs have been obtained and a number of large oil and gas fields have been found. After the breakthroughs of Kaijiang-Liangping trough, how reef-bank exploration will proceed? Is there another “Kaijiang-Liangping trough” in Sichuan basin? Previous research shows that Sichuan basin underwent intracratonic rift and basement fault activities in Late Permian, developing a paleogeography framework of “three uplifts and three depressions” under the background of the regional large ramp, including Exi (鄂西)-Chengkou (城口) trough, Kaijiang-Liangping trough and Yanting (盐 亭)-Tongnan (潼南) trough. Based on sedimentology and tectonics dynamics analysis, data of drillings, outcrops and seismic, Yanting-Tongnan trough has been discovered in central Sichuan basin in our study which distributes from Mianzhu (绵竹), Jiangyou (江油) in western Sichuan basin through Nanchong (南充) to Guang’an (广安), as long as about 210 km, extending in NW-SE nearly paralleling to Kaijiang-Liangping trough, opening to the sea north-westward, and gradually pinchout to the east platform. Similar to Kaijiang-Liangping trough, another platform margin reef belt distributes along a U-shape belt around Yanting-Tongnan trough, which is expected to become another natural gas accumulation zone after the platform margin around Kaijiang-Liangping trough. The discovery of Yanting-Tongnan trough expands favorable reef exploration area from original 2×10⁴ km² on both sides of Kaijiang-Liangping trough to more than 6×10⁴ km² in Yanting-Tongnan trough platform margin belt and Kaijiang-Liangping platform margin belt, greatly enlarging the reef exploration field. But compared to Kaijiang-Liangping trough, Yanting-Tongnan trough is relatively shallower and smaller, and the scale and quality of reef-bank reservoirs in its margin belt is a little poor relatively. Therefore, much research should be done timely such as comparative study of two troughs, detailed research of formation and evolution of the trough, regularity of reef migration, meticulous depiction of reef-bank reservoir size and distribution in order to obtain major breakthroughs around the Yanting-Tongnan trough.

鄂尔多斯盆地奥陶系马家沟组发育碳酸盐岩—膏盐岩共生体系沉积，马家沟组四段(马四段)是马家沟组沉积厚度最大的一套海侵碳酸盐岩沉积层，长期以来是天然气勘探关注的重点层位。基于地球物理、钻井岩心及有机地球化学等资料，重新认识了鄂尔多斯盆地奥陶系盐下古构造、储层分布、烃源岩和圈闭等成藏条件，并取得以下成果认识：(1)盐下马四段天然气为油型气，主要来自奥陶系盐下海相烃源岩，该套烃源岩生烃母质除常规干酪根外，还发育分散有机质、有机酸盐，生烃物质丰厚，具备规模生烃潜力；（2）奥陶纪鄂尔多斯盆地中东部坳陷存在乌审旗—靖边古隆起和东部盐下低隆两大次级构造单元，分别控制了盐下马四段台内滩、台内丘白云岩储层的发育，储集空间主要为白云岩晶间孔；(3)盆地中东部盐下马四段台内滩、台内丘白云岩上覆厚层膏盐岩封盖，上倾方向致密石灰岩侧向遮挡，海相烃源岩供烃，形成了大面积分布的自生自储式岩性气藏。在新的地质理论认识的指导下，针对鄂尔多斯盆地奥陶系盐下马四段部署的风险探井MT1井钻遇气层43.4m，采用水力加砂压裂新工艺，试气获35.24×104m3/d的高产工业气流，实现了盆地战略接替领域的重大突破。

The carbonate-evaporite paragenetic deposits are developed in the Ordovician Majiagou Formation in Ordos Basin. The fourth member of Majiagou Formation (Ma 4 member) is composed of a set of transgressive carbonate rocks with the largest thickness in Majiagou Formation, which has always been the target layer for natural gas exploration. Based on geophysical, drilling, core samples and organic geochemical data, the hydrocarbon accumulation conditions such as paleo structure, reservoir distribution, source rocks and trap are restudied, and the following achievements are obtained: (1) Natural gas in Ma 4 member is oil-type gas, generated by marine source rock of the subsalt Ordovician. In addition to conventional kerogen, the source rock has a large amount of parent materials for hydrocarbon generation, such as the dispersed organic matter and organic acid salt, showing great potential of hydrocarbon generation; (2) In the Ordovician, two secondary structural units, Wushenqi-Jingbian paleo uplift and the eastern subsalt low uplift, were developed in central-eastern depression in Ordos Basin, which controlled the development of dolomite reservoir in the intra-platform shoal and intra-platform mound of Ma 4 member, with the main reservoir space of intergranular pores; (3) The wide spread self-generation and self-storage type lithologic gas reservoir is formed in the central-eastern Ordos Basin by marine source rocks of subsalt Ordovician, reservoir of the intra-platform shoal and intra-platform mound dolomite of Ma 4 member, and cap rocks of the overlying thick evaporites and the lateral barrier provided by tight limestone in the updip direction. Guided by the new geological understanding, the risk exploration Well MT1 was drilled targeting at Ma 4 member, in which a gas layer of 43.4 m was penetrated, and high gas flow of 35.24×104 m3/d was tested by applying new hydraulic sand fracturing technology, achieving a major breakthrough in strategic replacement field in the basin.