页岩气是指吸附在页岩中的天然气或自生自储在页岩纳米孔隙中连续聚集的天然气。新世纪以来,美国发生的页岩气革命影响了世界油气资源格局;中国的非常规油气储存量非常可观,是世界上具有页岩气可采储量最大的国家;但页岩气地质条件、水平钻井、分段压裂等技术储备和页岩气管理经验等还面临很大挑战。近年来,中国大力推进页岩气的开发利用,中石化、中石油和延长油田三家公司在示范区块开发的成功,以及短时间内在勘探开发方面取得的技术突破,标志着中国页岩气的开发已取得了实质性突破。但中国今后是否采取页岩气开发对多元资本开放的模式,还需要进一步研讨。

摘　要： 湘西北地区牛蹄塘组黑色页岩展布广泛，为寒武纪纽芬兰世一第二世滞留还原条件的沉积产物，适中的埋深和较大的厚度为其提供了良好的气藏条件。对其有机地化参数进行试验分析：TOC值为0．59％-13．05％，均值3．75％，有机质丰富；R。值为1．87％-4．00％，均值3．05％，成熟度高；干酪根类型以Ⅰ型为主，少量为Ⅱ型，具有良好的生气潜力；矿物组成中脆性矿物含量为33％～87％，平均含量为68％，而黏土总量为13％～43％，平均为26％，脆性矿物／黏土矿物值高，有利于储层改造；页岩孔隙度为0．3％～8．0％，平均为3．3％，渗透率均小于0．04×10^-1μm^2，为低孔低渗类型。综合研究表明，牛蹄塘组具有良好的页岩气生储潜力，同时运用条件概率体积法对其资源量进行评估计算，资源量十分可观。在此基础上对湘西北地区牛蹄塘组划分出6个页岩气有利区，为进一步实施页岩气勘查提供依据。

摘　要： 湘西地区从南华纪以来经历了两次大规模前陆盆地的形成与演化过程，南华纪一志留纪末期海相前陆盆地形成阶段和泥盆纪一早白垩世陆相前陆盆地形成阶段。其沉积环境演化模式为：海相前陆盆地的形成与演化经历了大陆裂谷碎屑岩阶段、被动大陆边缘碎屑岩陆棚一碳酸盐岩陆棚一碳酸盐台地阶段、前陆盆地早期海相复理石阶段、前陆盆地晚期海相磨拉石阶段，缺失前陆盆地晚期陆相磨拉石阶段，且前陆盆地晚期海相磨拉石阶段短暂，前陆盆地早期海相复理石阶段长久。陆相前陆盆地的形成与演化经历了大陆裂谷拉张碎屑岩阶段、被动大陆边缘碳酸盐台地一台盆阶段、前陆盆地早期海相复理石阶段、前陆盆地晚期陆相磨拉石阶段，缺失前陆盆地晚期海相磨拉石阶段，且前陆盆地早期海相复理石阶段短暂，而前陆盆地晚期陆相磨拉石阶段长久。两次前陆盆地形成过程的差异受控于构造运动中古地理位置：第一次海相前陆盆地受控于其东南缘华南洋的形成、发展与消亡，为近被动大陆边缘海相前陆盆地；第二次陆相前陆盆地受控于北部勉略洋的形成、发展与消亡，为远被动大陆边缘陆相前陆盆地。湘西地区复合叠加型前陆盆地的形成与演化反映了整个扬子地台边缘的构造、沉积演化历史，对应于两次威尔逊旋回。

湘西地区发育志留系中、下志留统碎屑岩地层,缺失上志留统.经沉积学综合研究,可以划分出滞留盆地、浊积扇、三角洲、潮坪-滨岸等沉积体系,从下向上海平面逐渐下降,其物源来自于东南部雪峰隆起.湘西地区志留纪沉积盆地构造演化经历了前陆盆地的形成期、发展期及萎缩期、消亡期几个阶段.其沉积-构造演化规律为:前陆盆地初始形成期发育深水滞留盆地沉积体系;前陆盆地发展期发育海相浊积扇沉积体系;前陆盆地萎缩期发育三角洲沉积体系,前陆盆地消亡期发育潮坪-沙坝-滨岸沉积体系.

湖南保靖地区是页岩气勘探新区块。通过多口页岩气钻井的勘探实践，应用岩心描述、有机地球化学测试和扫描电镜观察等方法，系统总结了研究区下志留统龙马溪组页岩气成藏地质条件，并揭示其富集成藏的主控因素，为下一步勘探部署提供理论依据。湖南保靖地区下志留统龙马溪组黑色页岩分布广、厚度较大、有机质丰度高、热演化程度高、岩石中硅质含量高、储层裂缝发育程度高、孔渗条件较好、埋深适中，储集空间和运移通道充足，气测值较高，具有形成页岩气藏的有利地质条件。预测保靖县东南部甘溪—大坨地区为页岩气勘探有利区。

The Middle Triassic was the changing turning period of South China from marine sedimentary basin to continental deposits or even erosion. In this paper, South China is subdivided into four sedimentary provinces: Cathaysia sedimentary province, Low Yangtze sedimentary province, Upper Yangtze sedimentary province and Youjiang sedimentary province, among which the distribution and variation of the lithostratigraphic sequences, lithofacies and biotas are summarized. Each sedimentary province has similar stratigraphic sequence and unique lithofacies though the difference between the Anisian and the Ladinian is apparent. In the Anisian, carbonate rocks are mainly on Yangtze block, while clastic sediments are mostly distributed in Cathaysia and Youjiang sedimentary provinces. The mixed sequences of carbonate and clastic rocks mainly occur at the transition areas between the sedimentary provinces. In the Ladinian, carbonate sediments were limited, mainly in Upper Yangtze sedimentary province. Cathaysia, Lower Yangtze and Youjiang provinces were occupied by clastic sediments. In addition, biotas were of distinctive assemblages and associated biotic groups in various lithofacies. In Youjiang province, Daonella group and ammonoids are the most distinctive biota, while Upper Yangtze province is characteristic of widespread Costatoria subgroup, Cathaysia and Lower Yangtze provinces are predominated by Asoella subgroup. So there is a close relationship between the biotic paleoecology and the lithofacies as well as the sedimentary facies in South China during the Middle Triassic. The Cathaysia block and the Lower Yangtze sedimentary province belonged to a single sedimentary paleogeographic unit while the Upper Yangtze and Youjiang sedimentary provinces were another affiliated unit in the Middle Triassic. The paleogeographic pattern of the former was a continent marginal sedimentary basin declining northwestward. From the Anisian to the Ladinian, the sedimentary facies zones migrated northwestward rapidly. The whole region finished the transformation from sea to land in the latest Anisian. In the latter, the Middle Triassic paleogeography was a typical pattern of continental margin deepening from north to south, accompanied by an accordant differentiation of sedimentary facies. From the Anisian to the Ladinian, the enormous shallow carbonate platform, the main body of Upper Yangtze province, became shallower and saltier, and the clastic turbidites, the main body of Youjiang province, gradually expanded over the carbonate platform. Consequently, the Middle Triassic completely records the course of each sedimentary province from sea to land and their relationship, which is important to study the regional tectonics and geological history of South China. There exists a great interrelationship between the biotic paleoecology and the lithofacies as well as the sedimentary facies in South China during the Middle Triassic. The variation of ecological types and the change of biotic composition well show the history of the regional paleogeographic change and the development of sedimentary basin in this region. Cathaysia Lower Yangtze and Upper Yangtze-Youjiang were two separate sedimentary basin and have quite different evolutionary histories, which indicates that they had different dynamics in the transition from sea to land.

中三叠世是中国南方沉积盆地从海相沉积向陆相沉积转变的重要时期, 因此阐明该期的地层结构和沉积古地理分异对于揭示该区域构造和地质发展历史是相当重要的。本文将中国南方划分为四个沉积区 :东南沉积区、下扬子沉积区、上扬子沉积区及右江沉积区。同时对各沉积区序列、岩相生物群的分布和分异进行了总结。从而认为当时东南沉积区与下扬子沉积区是一个直接关联的沉积古地理整体, 而上扬子沉积区与右江沉积区为另个沉积古地理整体。前者在中三叠世时是一个南东高, 北西低的向北西方向倾斜的陆缘海沉积盆地, 从安尼期至拉丁期, 沉积相带不断向北西方向迁移, 并在安尼期与拉丁期之交完成从海向陆的转变。

Abstract: The Yuanling-Mayang basin is a giant Mesozoic continental basin in the middle segment of Xuefeng orogen. At present, the features of the Mesozoic-Cenozoic faults and folds in the basin is lack of systematic and deep research. The authors studied such aspects of this problem as Mesozoic-Cenozoic structural framework, characteristics of the faults and folds, deformation sequences and epochs and regional tectonic settings through tectonic profile and field geological investigation, and reached the following conclusions: (1) The principal tectonic framework of the Yuanling-Mayang basin is composed of NNE- to NE-trending normal faults, thrust faults and gentle folds, accompanied by other folds and faults of different trends and natures. In the western and middle basin, main deformations are normal faults which formed complex horst-graben structure, with weak fold deformation. On the east margin of the basin, controlled by the Huaihua-Yuanling fault belt, there occur strong deformations, such as thrust faults which mostly dip east and subordinately dip west, often accompanied by overturned tight folds. (2) The basin has undergone several tectonic events since Middle Triassic: ① Regional NW to NWW-striking compression in late Middle Triassic Indosinian movement which formed NE to NNE-trending folds and thrust faults. ② Regional NS-striking compression during Late Triassic-Early Jurassic which formed EW-trending folds and kinks. ③ Regional NWW to EW-striking compression in late Middle Jurassic Yanshanian movement which formed NS- and NNE-trending folds and thrust faults involving Upper Triassic and Lower-Middle Jurassic on the east margin of the basin. ④Regional NW-SE striking extension in Early Cretaceous which formed NE- to NNE-trending normal faults of different scales. ⑤ Regional NS-striking extension in Late Cretaceous which formed EW-trending normal fault. ⑥ Regional NE-striking compression during middle-late Paleogene which formed NW-trending folds and thrust faults, NEE- to NE-trending sinistral strike-slip faults, NNE-trending dextral strike-slip faults, and NEE- or NNE-trending conjugated shear joints involving Cretaceous and early layers. ⑦Regional NW compression during late Late Paleogene-Early Neogene which formed NE-trending folds, NE- to NNE-trending thrust faults and NS-trending thrust faults involving Cretaceous and early layers. Among them, the most important deformations are normal faults which originated from the NW-SE-striking extension in Early Cretaceous, the folds and thrust faults originated from the NW-striking compression during late Late Paleogene-Early Neogene. (3) The klippes located in the eastern basin and east periphery, defined by Previous researchers, such as Wangbinpo, Huangjin’ao, Tanwan and Mayang, do not exist. The so-called “klippes” are actually faulted blocks with deep roots, and the Banxi Group located in Paleozoic and Mesozoic were related to the movement of thrust faults or normal faults.

提要：沅麻盆地是叠加在雪峰造山带中段的一个中生代大规模陆相盆地，盆地中新生代断裂、褶皱发育特征尚缺乏系统、深入的研究。本文通过构造剖面测制、野外路线调查并结合区域地质资料，对沅麻盆地中新生代构造格架、褶皱和断裂的发育特征、变形序列、时代及区域构造背景等进行了详细的分析研究，取得以下主要认识和进展。（1）NNE-NE向正断裂、逆断裂和平缓褶皱（主要为向斜）组成沅麻盆地的主体构造格架，同时发育其他多组不同方向、性质的褶皱和断裂。盆地西部和中部大部以正断裂为主，形成复杂的堑-垒构造格局，褶皱变形强度低；盆地东缘因区域怀化—沅陵断裂带控制而变形强烈，以多为东倾、少量西倾的逆断裂为主，常伴有倒转紧闭褶皱。（2）中三叠世以来沅麻盆地经历多期构造变形事件：①中三叠世晚期印支运动中受区域NW—NWW向挤压而形成NE—NNE向褶皱和逆断裂；②晚三叠世—早侏罗世期间受区域SN向挤压，形成EW向褶皱和膝折；③中侏罗世晚期早燕山运动中受区域NWW—近EW向挤压，形成盆地东缘上三叠统—中侏罗统卷入的SN向和NNE向褶皱和逆断裂；④早白垩世区域NW-SE向伸展作用下形成不同规模的NE—NNE向正断裂；⑤晚白垩世在区域SN向伸展体制下形成EW向正断裂；⑥古近纪中晚期受区域NE向挤压，形成卷入白垩系及先期地层的NW向褶皱、NW向逆断裂、NEE—NE向左行走滑(或兼逆冲)断裂、NNE向右行走滑断裂、NEE向与NNE向共轭剪节理等；⑦古近纪末—新近纪初在区域NW向挤压下，形成最新卷入地层为白垩系的NE向褶皱、NE-NNE向逆断裂、SN向逆断裂。上述多期变形中以早白垩世NW-SE伸展形成的正断裂和古近纪末—新近纪初NW-SE向挤压形成的褶皱和逆断裂最为重要，其次为中侏罗世晚期NWW—近EW向挤压下形成的褶皱和逆断裂。（3）前人提出的沅麻盆地东部及东侧外围地区发育的王炳坡、黄金坳、潭湾、麻阳等“飞来峰”构造并不存在，所谓“飞来峰”实为向下“生根”的断夹块，组成“飞来峰”的板溪群座立于古生界和中生界之中与逆冲断裂或正断裂活动有关。

The erosion thickness and paleogeothermal gradient of the Pengshui area in the eastern Sichuan Basin during various tectonic movements were established by means of vitrinite reflectance forward modeling and basin modeling software (BasinMod 1-D). Since the Late Paleozoic, the paleo heat flow and paleogeothermal gradient in the study area first increased and then decreased. The average paleogeothermal gradients from Silurian to the Middle Permian, from the Middle Permian to the Early Cretaceous, and from the end of the Early Cretaceous until now were 25–30 °C/km, 30–35 °C/km, and 20–25 °C/km, respectively. In the Caledonian and Indosinian periods, the erosion thickness of the study area was less than 500 m; while in the Yanshanian and Himalayan periods, it reached 4 300 m. The Wufeng and Longmaxi shales entered the threshold of oil generation in the Early Devonian, and reached peak generation from the Late Permian to the Late Triassic. Gas generation started in the Early Jurassic, and over-mature dry gas was generated in the Middle Jurassic. In the following Yanshan and Himalayan movements, the study area was uplifted and eroded, which raised challenges for the preservation of shale gas.

利用盆地模拟软件BasinMod 1-D,选用古地温梯度法,采用镜质体反射率正演法厘定彭水地区各时期构造剥蚀量及古地温梯度。结果表明,该区自晚古生代以来古热流经历了低—高—低的变化过程,其古地温梯度具有相同特征;志留纪—中二叠世古地温梯度平均值约为2.5~3.0 ℃/hm;晚二叠—早白垩世古地温梯度平均值约为3.0~3.5 ℃/hm;早白垩世末期以来,古地温梯度平均值介于2.0~2.5 ℃/hm;加里东期、印支期构造抬升剥蚀量不足500 m,燕山、喜马拉雅运动构造抬升剥蚀量可达4 300 m。成烃史研究表明,彭水地区五峰—龙马溪组页岩早泥盆世进入生油门限,在晚二叠—晚三叠世进入生油高峰,在早侏罗世进入生气期,中侏罗世进入过成熟生干气阶段。后期燕山、喜马拉雅运动,致使地层抬升、剥蚀,研究区页岩气保存条件将成为下一步勘探的研究重点。

中、上扬子区寒武-志留系发育两套主力烃源岩:下寒武统牛蹄塘组页岩为主的烃源岩和下志留统龙马溪组连同上奥陶统五峰组笔石页岩为主的烃源岩.研究区曾遭受多期复杂的构造变动,烃源岩经历了不均一的抬升、变形、埋藏作用,导致烃源岩生烃演化的不连续性和分阶段性.基于详细的构造-埋藏史研究,烃源岩现今热演化程度分析,运用BasinMod盆地模拟技术,烃源岩生烃热模拟方法,深入研究了寒武-志留系烃源岩的埋藏史、受热史和生烃史,揭示出研究区寒武-志留系有机质生烃演化的阶段性和区域演化规律性,阐明了寒武-志留系烃源岩生烃作用发生的构造期次、时空分异特征等.认为鄂西-渝东区为下寒武统烃源岩主力生烃区,而川东南-黔中区为下志留统烃源岩主力生烃区.生烃热模拟实验再现了烃源岩生烃历程,借此探讨了高过成熟海相烃源岩剩余产烃潜力.

摘　要： 通过录井、测井、地震、野外剖面与岩心资料的深入剖析，探讨中上扬子地区下志留统页岩段的沉积相与总有机碳的关系，预测页岩气有利勘探区。中上扬子地区下志留统龙马溪组为一套20～268m厚的黑色页岩夹灰绿色泥质粉砂岩沉积，在等时框架内自下而上可识别出2个三级层序即SQ1与SQ2，它们分布稳定、可对比性好。下部层序（SQ1）的海侵体系域（TST）发育一套有利于页岩气形成的富有机质页岩，此时期呈现出“北面向次深海敞开、东西南三面受古陆围限、陆棚广布”的沉积格局，深水陆棚相广泛发育，面积为255000km2，平均厚度35m。受海平面下降的影响，从下部层序至上部层序水体变浅，岩相从深水陆棚相黑色页岩向中-浅水陆棚相沙纹层理粉砂质页岩转变。岩相的发育受海平面升降、古陆、海底地形、物源供给等因素的影响，岩相类型有碳质或硅质或钙质页岩、纹层状页岩、生物扰动粉砂质页岩、沙纹层理的粉砂质页岩、块状砂岩或介壳灰岩薄夹层5类。研究表明，沉积相对富有机质页岩的形成具有内在的控制作用，高TOC含量页岩发育于深水陆棚相、中陆棚相和溻湖相中。目前，已有多口井在龙马溪组页岩获得工业气流，揭示了该区良好的页岩气勘探前景；综合分析认为涪陵-赤水-仁怀、威远-长宁、鄂西-渝东为中上扬子地区下志留统页岩气勘探的主要方向和有利目标区。

Shale oil is liquid hydrocarbon reserved in effective argillaceous source rocks with free phase, adsorbed and dissolved phase. Recent years, America has achieved great success in commercial shale oil production, whereas shale oil research in China is still in its infancy with more related theory innovations. Based on shale oil characteristics and experience of American shale oil exploration and development, this paper analyzed and summarized the research progress and some significant cognition in shale oil forming conditions, reservoir features, accumulation mechanism and evaluation method at home and abroad. The systematical comparison of shale oil characteristics between China and America shows that Chinese shale oil mainly deposited in semi-deep and deep lacustrine, and black shale spreads widely, featured by great thickness, complex structures with frequent sandy interbedding. Preferable shale rich in organic matter usually coexists with other lithologies in laminated texture, and the kerogen type of organic matter is predominantly sapropelic with R o of 0.5%～1.2% and TOC more than 2.0%. Relative high content of fine-grained carbonate and clay exceeding 50% results in a poor reserving capacity. Hydrocarbon-generation condition and reserving capacity significantly control lacustrine shale oil accumulation, simultaneously with additional preserving conditions taken into account in strong tectonic activity areas, such as in the rifted basins. Mixed-type and fractured-type shale oil overall have a huge exploration potential, and the matrix-type follows. In order to promote shale oil research and realize shale oil production earlier in China, the fundamental researches should be on the basis of theories study, and prominently focus on hydrocarbon occurrence, micro pore structure, retained oil accumulation mechanism, structure- preserving condition, evaluation system and resource evaluation method. The purpose of these studies is to provide theoretical guidance for the high efficient exploitation of shale oil in China.

页岩油是指以游离态、吸附态及少量溶解态赋存于泥页岩层系中的原油，目前已在美国实现商业 开采，而我国页岩油研究起步晚，相关基础理论研究还比较薄弱。 在页岩油一般特征分析的基础上，结 合近年来美国海相页岩油勘探开发实践，总结了国内外在页岩油形成条件、储层特征、成藏机理及评价 方法等方面取得的进展和重要认识。 对中国和美国页岩油发育特征的系统对比与分析结果表明：我国 湖相暗色泥页岩分布广、厚度大、结构复杂，与砂质互层频繁；富有机质泥页岩发育较好， TOC 质量分数 一般大于 2% ，但成熟度普遍偏低（ R o 为 0.5%～1.2% ）；细粒碳酸盐和黏土矿物含量较高（质量分数大于 50% ），储集物性较差；页岩油成藏主要受生烃条件（特别是成熟度）和储集条件控制，而在断陷等构造强 烈地区还受保存条件的影响；混合岩性型和裂缝型页岩油总体显示好，勘探潜力较大，基质型次之。 建 议在理论研究基础上，重点在页岩油赋存机理、微观孔隙结构、页岩油滞留成藏机理、构造保存条件、勘 探评价体系和资源评价方法等方面展开研究，以期为我国页岩油勘探开发提供指导。