TECTONO‐STRATIGRAPHIC EVOLUTION OF THE NW SEGMENT OF THE ZAGROS FOLD‐THRUST BELT,KURDISTAN, NE IRAQ

The Kurdistan (NW) segment of the Zagros fold‐thrust belt, located in the Kurdistan Region of NE Iraq, forms the external part of the Zagros orogen and is bounded by the Zagros suture to the NE. To the SW is the Arabian Plate into which the deformation front has migrated progressively, beginning in the Late Cretaceous and culminating in the Tertiary. Regional compression resulted in obduction of the Mawat ophiolites and emplacement of the Avroman and Qulqula nappes onto the continental margin, and the formation of the Kurdistan foreland basin. In this paper, structural, stratigraphic and palaeontological data together with new field observations are used to investigate the tectono‐stratigraphic evolution of this basin, and to study the propagation of the deformation front from the Zagros Imbricate Zone in the NE towards the Mesopotamian foredeep in the SW. Six unconformities within the Kurdistan foreland basin succession are recognized: Turonian (base‐AP9; 92 Ma); Danian (base‐AP10; 65 Ma); Paleocene–Eocene (intra‐AP10; 55 Ma); late Eocene (top‐AP10; 34 Ma); middle‐upper Miocene (a local unconformity; intra‐AP11; 12 Ma); and Pleistocene. These unconformities can be divided into two groups; obduction‐related (Turonian, Danian, and Paleocene‐Eocene); and collision‐related (late Eocene, middle‐upper Miocene, and Pleistocene). The geographical position of the unconformities is used to determine the rate of propagation of the deformation front, which is estimated at ca. 3 mm/yr. This is in agreement with previous studies which suggested a NW‐ward decrease in the propagation rate. The rate was most rapid (2.95 mm/yr) in the Low Zagros Fold‐Thrust Zone and slower (2.06 mm/yr) in the High Zagros Fold‐Thrust Zone. The more rapid propagation rate in the former area may be attributed to the presence there of the Miocene Lower Fars Formation which acted as a shallow décollement surface. Within the Zagros fold‐thrust belt, the intensity of deformation decreases towards the foreland (SW). Deformation in the High Zagros Fold‐Thrust Zone is characterized by thrust imbricates and high amplitude fault‐propagation folds at the surface separated by narrow synclines. However, the Low Zagros Fold‐Thrust Zone (Simply Folded Belt) is characterised by detachments and low amplitude fault propagation folds separated by broad synclines. In the foredeep area, folds are confined to the subsurface. Deeply buried Jurassic units, together with Upper Cretaceous – Paleocene siliciclastics, and the evaporite‐dominated Lower Fars Formation may have acted as décollement surfaces in the NW segment of the Zagros fold‐thrust belt, and controlled the structural geometry and evolution of the area.     

A REVIEW OF PERMO‐TRIASSIC RESERVOIR ROCKS IN THE ZAGROS AREA,SW IRAN: INFLUENCE OF THE QATAR‐FARS ARCH

Four “supergiant” and numerous giant gasfields have been discovered in the Zagros area of SW Iran. The gasfields are concentrated in the eastern part of the foldbelt, in Fars Province and the adjacent offshore, and produce from Permo‐Triassic carbonates equivalent to the Khuff Formation. The carbonates belong to the upper member of the Dalan Formation and the overlying Kangan Formation. Reservoir rock quality is strongly influenced by tectonic setting and depositional environment, and also by diagenesis. The highest quality reservoirs occur in oolitic shoal facies; fracturing (especially in onshore fields) and dolomitisation (in offshore fields) have also influenced reservoir quality. Anhydrite plugging is common in reservoirs in offshore fields, while calcite cementation is dominant in onshore reservoirs. Facies variations in the Dalan‐Kangan Formations appear to correspond to syndepositional palaeohighs and depocentres. In the Eastern Zagros (Fars area), thickening of the Dalan Formation corresponds to a Mid‐Late Permian depocentre referred to here as the Permian Fars Basin. As a result of sea level fall, this depocentre evolved into a hypersaline lagoon with evaporite deposition (Nar Member). In the Triassic, the depocentre evolved into a palaeohigh as indicated by thinning and facies changes in the Kangan Formation. The results of this study draw attention to variations in the reservoir quality of the Dalan‐Kangan Formations. Much of this variation was due to the influence of the Qatar‐Fars Arch.     

酒泉盆地白垩纪-新生代区域构造演化与油气勘探

酒泉盆地位于祁连造山带北缘西部,是走廊盆地群西端的一个富油气盆地,按区内大地构造环境变迁、祁连造山带的形成演化、盆地内地层分布、构造变形特征,酒泉盆地白垩纪-新生代区域构造演化划分为3个阶段:早白垩世拉张断陷盆地演化阶段,晚白垩世-古新世挤压隆升阶段,始新世-渐新世坳陷和新近纪挤压盆地演化阶段。早白垩世拉张断陷阶段控制了下白垩统烃源岩及储集相带的分布,凸起区有利于形成潜山油气藏;晚白垩世-古新世的挤压隆升形成盆地的反转构造圈闭;始新世-渐新世坳陷和新近纪挤压盆地演化促进了烃源岩成熟演化,形成了众多的构造圈闭,是盆地油气聚集的主要时期。新生代前陆盆地南缘山前冲断带构造油气藏及早白垩世断陷构造-地层、岩性油气藏是酒泉盆地今后油气重点勘探领域。     

LATE CRETACEOUS TECTONIC AND SEDIMENTARY EVOLUTION OF THE BANDAR ABBAS AREA,FARS REGION,SOUTHERN IRAN

The Upper Cretaceous succession in the SE Zagros (Bandar Abbas area) is characterized by marked changes in fades and thickness. These changes relate to sediment deposition in a foreland basin along the NE margin of the Arabian plate. The succession was measured at eight outcrop sections in the Khush, Faraghun, Gahkum, Genow and Khamir anticlines. The measured sections illustrate a transition from shallow‐water carbonate platform deposits (Cenomanian to Coniacian) to deep‐water fades (Santonian to Maastrichtian). Outcrop observations were compared to data from ten off‐ and onshore wells and to a series of seismic profiles. Four cross‐sections were constructed using well and outcrop data and illustrate fades and thickness variations within the Upper Cretaceous. Based on these regional profiles, the Late Cretaceous depositional history of the Bandar Abbas area was reconstructed and can be divided into two tectono‐sedimentary phases suggesting a transition from a passive to an active margin. Sedimentation during Phase I (late Albion to Coniacian) took place in shallow‐water carbonate platform and intrashelf basin settings (Sarvak Formation), and four third‐order sequences can be recognised. The uppermost sequence is locally capped by fresh‐water, pisolith‐bearing carbonate sand and conglomerates with local laterite and palaeosols of the Coniacian Laffan Formation. Shallow‐water facies consist mainly of wackestone to packstones with abundant benthic foraminifera. Sediments deposited in intrashelf basins are dominated by oligosteginid‐bearing fades. Eustatic variations in sea level, the creation of a foreland basin and salt tectonics most probably controlled patterns of sedimentation during this phase. During the second tectono‐sedimentary phase (Phase II: Santonian to Late Maastrichtian), sediments were dominated by pelagic marls and gravity flow deposits. Lateral thickness variations become more marked to the NE as a result of obduction processes and the creation of the foreland basin. Allochthonous ophiolitic and radiolarite‐bearing units are common in the northern part of the Fars region but are restricted to a few localities in the Bandar Abbas area. Traces of allochthonous materials occur in the SE‐most part of the Khush anticline; thrust slices in offshore seismic profiles may link to the Hawasina nappes of Oman. At the top of the Phase II succession, pelagic facies locally interfinger with Omphalocyclus and Loftusia‐bearing fades (Tarbur Formation) and evaporites (Sachun Formation). These deposits are overlain by slumped and dolomitized shallow‐water carbonates of the Paleocene – Eocene Jahrum Formation. The sedimentary sequence in the Bandar Abbas area illustrates a far‐field response to Late Cretaceous obduction processes and foreland basin development, as well as to halokinetic activity. Rapid variations in thickness and fades document the evolution of depositional processes in the foreland basin.     

BURIAL,TEMPERATURE AND MATURATION HISTORY OF CRETACEOUS SOURCE ROCKS IN THE NW PERSIAN GULF,OFFSHORE SW IRAN: 3D BASIN MODELLING

This study presents a 3D numerical model of a study area in the NW part of the Persian Gulf, offshore SW Iran. The purpose is to investigate the burial and thermal history of the region from the Cretaceous to the present day, and to investigate the location of hydrocarbon generating kitchens and the relative timing of hydrocarbon generation/migration versus trap formation. The study area covers about 20,000 km² and incorporates part of the intra‐shelf Garau‐Gotnia Basin and the adjacent Surmeh‐Hith carbonate platform. A conceptual model was developed based on the interpretation of 2700 km of 2D seismic lines, and depth and thickness maps were created tied to data from 20 wells. The thermal model was calibrated using bottom‐hole temperature and vitrinite reflectance data from ten wells, taking into account the main phases of erosion/non‐deposition and the variable temporal and spatial heat flow histories. Estimates of eroded thicknesses and the determination of heat‐flow values were performed by burial and thermal history reconstruction at various well and pseudo‐well locations. Burial, temperature and maturation histories are presented for four of these locations. Detailed modelling results for Neocomian and Albian source rock successions are provided for six locations in the intra‐shelf basin and the adjacent carbonate platform. Changes in sediment supply and depocentre migration through time were analyzed based on isopach maps representing four stratigraphic intervals between the Tithonian and the Recent. Backstripping at various locations indicates variable tectonic subsidence and emergence at different time periods. The modelling results suggest that the convergence between the Eurasian and Arabian Plates which resulted in the Zagros orogeny has significantly influenced the burial and thermal evolution of the region. Burial depths are greatest in the study area in the Binak Trough and Northern Depression. These depocentres host the main kitchen areas for hydrocarbon generation, and the organic‐rich Neocomian and Albian source rock successions have been buried sufficiently deeply to be thermally mature. Early oil window maturities for these successions were reached between the Late Cretaceous (90 Ma) and the early Miocene (18 Ma) at different locations, and hydrocarbon generation may continue at the present‐day.     

East Venezuela盆地油气聚集与勘探潜力

East Venezuela盆地是一个大型的不对称前陆盆地,具有丰富油气资源。古生代以来,经历了晚三叠世—侏罗纪裂谷、白垩纪—始新世被动边缘和渐新世至今前陆盆地3个演化阶段。纵向上沉积地层可划分为前白垩系、白垩系和后白垩系3套巨层序。East Venezuela盆地最主要的烃源岩是Guayuta群和Tigre组海相泥页岩和碳酸盐岩。生油岩成熟度由北往南递减。北部烃源灶油气经断层、砂体长距离阶梯式向南部斜坡边缘运移。盆地最主要圈闭类型为背斜、断块、地层和岩性圈闭。Oficina组构造、构造—地层、地层圈闭组合和Naricual组构造圈闭组合是盆地内最主要的两套成藏组合。有潜力的勘探领域包括白垩系—下中新统被动边缘沉积层序、盆地中部前渊区、南部重油带和东部海域。     

鄂尔多斯多旋回叠合盆地形成与演化

鄂尔多斯盆地奠基于太古代-早元古代的结晶基底之上,其演化过程以稳定发育为特征,但其稳定性和活动性是对立统一、协调发展的。以钻井资料和地震资料为基础,恢复了各时期的古构造形态。结合沉积特征,将盆地演化划分为4个主要阶段,即中晚元古代坳拉谷盆地发育阶段、古生代大型稳定克拉通盆地发育阶段、中生代前陆盆地发育阶段、新生代周缘断陷盆地发育阶段。指出盆地早期演化主要受中央古隆起控制,表现为中部隆,东、西坳的古构造格局;晚期演化主要受后期改造的影响,表现出西部持续坳陷、东部整体掀斜的古构造格局;二叠纪石千峰期为这2种构造格局转换的关键时期。     

酒泉盆地中、新生代构造演化及沉积充填特征

酒泉盆地晚中生代处于伸展裂开环境，新生代处于挤压聚敛环境，它是经历了早白垩世伸展断陷期和第三纪挤压增陷期两期构造旋回，即早白垩世断陷盆地演化阶段和新生代前陆盆地演化阶段，中，新生界沉积盖层具断坳叠竖的双层结构。酒泉盆地在早白垩世经历了箕头断陷形成期，凹陷扩展期，碟状坳陷3个主要演化阶段，新近纪以来强烈的逆冲推覆作用以及剪切作用肢解，改造了晚中生代断陷盆地，图2参7     

前陆盆地的类型及油气远景

根据前陆盆地形成的大地构造背景,前陆盆地可分为5类,即周缘前陆盆地。弧后前陆盆地。破裂前陆盆地。陆内前陆盆地和走滑前陆盆地。前陆盆地形成于挤压构造环境,具有一些相似的成因特征,如沉降中心与沉积中心不一致;沉降曲线呈陡、缓、陡3段;沉积物遭受挤压变形.根据变形强度的差异.可分出3到5个变形带等。形成于不同大地构造背景中的前陆盆地具有不同的充填特点和盆地结构,也具有不同的油气远景。周缘前陆盆地是由于陆-陆碰撞,在俯冲板块上产生的挠曲盆地,常由被动大陆边缘裂谷盆地转化而成。盆地充填具有双层结构,早期发有复理石前陆盆地,堆积厚度巨大,发育厚度较大的生油岩系;后期发育磨拉石前陆盆地,为向上变粗的序列,发育有较厚的储集岩系。这类前陆盆地具有极好的油气远景。孤后前陆盆地与A型俯冲作用有关,可以由弧后裂谷盆地转化而成。盆地充填可具双层结构或仅有单后结构,早期发育火山复理石前陆盆地,堆积厚度大,发育有较厚的生油岩,后期为火山磨拉石盆地。这类前陆盆地具有较好的油气远景。破裂前陆盆地的形成是因基底卷入前陆变形作用,造成了块状隆起和基底褶皱所分隔的孤立盆地。这类盆地中沉积岩层厚度不大,油气远景欠佳。陆内前陆盆地形成于板内,远离碰撞造山带,可能与碰撞造山带的远程效应有关。盆地充填具双层或单层结构,以发育磨拉石前陆盆地为主,早期复理石不发育。这类前陆地具有一定的油气远景。走滑前陆盆地发育于大型陆内走滑系的两侧,伴有拉分盆地,盆地充填具单层结构,发育磨拉石前陆盆地,沉积中心明显呈雁行排列。这类盆地油气远景有限。前陆盆地的结构具有不对称的特点。自造山带向盆地方向发育山前冲断带、前陆坳陷、前缘斜坡和前缘隆起等构造单元,相应地具有各自的油气藏分布模式。      

Oriente-Maranon盆地石油地质特征及勘探潜力

Oriente-Maranon盆地是古生代克拉通边缘基础上发展和形成的次安第斯山(Sub-Andeans)前陆盆地之一,经历了克拉通边缘盆地→裂谷盆地→前陆盆地3个演化阶段。盆地内主要的烃源岩及储、盖组合均发育在裂谷盆地阶段,三叠系—侏罗系Pucara群和白垩系Chonta组2套主要烃源岩的排烃高峰期分别是古新世—始新世(距今60~45 Ma)和中新世(距今15~5 Ma)。Chonta组自生自储组合是最重要的成藏组合。盆地西部发育逆冲断层/褶皱圈闭和基底卷入圈闭,中部发育挤压或披覆背斜,东部发育牵引背斜圈闭,不同类型的圈闭沿北西—南东走向呈带状分布。有潜力的勘探领域包括中西部白垩系Chonta组烃源岩供油区域的披覆和挤压背斜圈闭,中部和南部侏罗系Pucara群烃源岩供油区域的牵引背斜圈闭和挤压背斜圈闭,中部的Pucara群碳酸盐岩圈闭,北部和东部成熟探区上白垩统岩性圈闭和上古生界构造-地层圈闭。图5参13     

中国中西部前陆盆地成藏特征的初步分析

通过讨论川西(四川盆地西部)、柴北缘(柴达木盆地北缘)和准南缘(准噶尔盆地南缘)前陆盆地的成藏过程,指出我国中西部前陆盆地具有多期聚集、晚期聚气的成藏特征,认为我国中西部前陆盆地具有最重要的两大成藏期,一是燕山期及其之前的油气成藏期,主要是中部周缘前陆盆地和西部再生前陆盆地二叠系烃源岩和三叠系烃源岩的油气聚集期;二是喜山晚期,主要是受新构造运动影响,西部再生前陆盆地中、新生界烃源岩的油气成藏和中部周缘前陆盆地的油气调整期,其中中生界煤系烃源岩是中西部前陆盆地主要的烃源岩,而喜山晚期冲断作用形成的断层相关褶皱圈闭与前陆发育时巨厚沉积造成的中生界煤系烃源岩排烃过程相匹配。此外还讨论了前陆盆地中的古构造(背景)在油气聚集中的重要作用和早期前陆盆地成藏体系、再生前陆盆地成藏体系在油气相态及成因类型的平面分布特征上的控制作用。     

苏北-南黄海盆地构造演化

苏北及南黄海盆地是由多期、多类盆地叠加的复合残留盆地,地质概况基本相似,成因演化近同,自元古界下扬子板块形成后,主要经历了古-中生代地台、中生代前陆盆地、走滑拉分盆地时期以及新生代断陷、坳陷盆地时期.在古生代-中生代发展过程中是一个整体,晚白垩世盆地演化出现分化,发育伸展盆地群,形成一系列叠置在中、古生代盆地之上的箕状断陷,箕状断陷的发育及分布明显受中-古生界内部先存逆冲断裂的控制.     

六盘山盆地含油气远景预测

六盘山盆地处于华北古板块与甘青藏古板块的交界部位，其形成，发展与两大板块的相互作用密切相关。它是由晚古生代前陆坳陷和中新生代山前坳陷迭加而成的复合型盆地。发育地层为石炭－二叠系，侏罗系，白垩系和第三系。可分为海原坳陷，大关山逆冲带和小关山逆冲带三个构造单元。逆冲断裂发育，形成大量地面褶被。生油层以下白垩统和中下侏罗统为主，储层和盖层均发育良好，尤其中下侏罗统具有很好的自生自储条件，且已进入油门限。     

中东扎格罗斯盆地构造演化与油气分布

扎格罗斯盆地是中东地区重要的含油气盆地之一,已探明储量巨大。通过区域构造演化、盆地构造划分、油气分布特征和油气成藏主控因素研究,认为扎格罗斯盆地由被动陆缘盆地演化而成现今的前陆盆地,经历了早古生代克拉通—弧后伸展阶段、晚古生代弧后伸展阶段、中生代被动陆缘盆地阶段和晚中生代—新生代前陆盆地演化阶段。扎格罗斯山前缘断裂带和高扎格罗斯断裂带将盆地自西南向东北划分为前渊带、简单褶皱带和山前冲断带等3个构造带。扎格罗斯盆地前渊带以油田为主,简单褶皱带以气田为主,山前冲断带挤压构造变形强烈,油气难以保存。下白垩统Kazhdumi组烃源岩为中—新生界储层的主要油源,志留系Gahkum组泥页岩为古生界储层的主要气源;新生界碳酸盐岩为主力储层,其次是白垩系Sarvak组和上二叠统Dalan组碳酸盐岩;前渊带以蒸发岩和泥页岩盖层为主,简单褶皱带则以泥页岩盖层为主。背斜构造和盖层类型为油气成藏的主要控制因素。     

南海南部海域南薇西盆地新生代沉积特征

南薇西盆地主体奠基在南沙地块上 ,发育古新世—第四纪地层 ,最大沉积厚度为1 1 0 0 0m。通过分析区域地质背景和盆地沉积演化史 ,认为南薇西盆地是在南海北部被动大陆边缘上裂解形成的。成盆初期 (初始裂陷期 )与华南大陆相连 ,其沉积特征与南海北部新生代盆地类似 ,为陆相沉积环境。晚始新世以后 ,随着南海海底扩张 ,南沙地块裂离华南大陆并向南漂移 ,发生大规模海侵 ,盆地进入主裂解扩张期 ;至早渐新世 ,盆地渐次由海陆交互相过渡为海相 ;晚渐新世—中中新世 ,盆地逐渐由断陷转为断拗 ,沉积范围不断扩大 ,整体处于海相沉积环境。晚中新世以后 ,盆地进入浅海 半深海沉积环境的裂后热沉降期。通过对比解释大量地震资料 ,在盆地内划分出 3个超层序、6个层序 ,结合地震相的分析 ,对上新统以下的 4个层序进行了沉积相推断解析。     

准噶尔盆地沙湾凹陷构造-地层层序与盆地演化

研究准噶尔盆地沙湾凹陷的构造-地层层序及盆地演化,不仅对于认识盆地结构及油气勘探具有重要意义,同时对中亚造山带构造演化的研究也具有一定的启示。文章利用井、震结合的思路,精细追踪地震同相轴,结合连井剖面对比,分析石炭纪以来各地层内部的削蚀及超覆尖灭关系,并结合相应的构造体制转换过程,将研究区综合划分出6个大的构造层。依据断层相关褶皱理论开展精细构造解释,并利用平衡剖面技术,重点分析了沙湾凹陷自晚石炭世以来的构造演化。研究认为沙湾凹陷的形成演化经历了晚石炭世伸展断陷、早二叠世伸展拗陷、中二叠世—晚三叠世前陆盆地、侏罗纪陆内拗陷及压扭盆地、白垩纪—古近纪陆内拗陷及新近纪—第四纪陆内前陆盆地7个阶段,其演化过程主要受周缘边界断裂带多期活动的控制。西边界的红车断裂带在晚海西运动中期（P₂）,印支运动晚期（T₃）及燕山运动中晚期（J₂-E）的强烈扭压作用对沙湾凹陷的构造演化及相应地层的发育与分布影响最强。     

柴达木盆地中、新生代构造演化及其对油气的控制

在综合分析区域构造背景、边界条件、基底性质、构造运动、不整合面、地层分布、沉积特征和构造演化史的基础上,认为柴达木盆地中、新生代的构造演化经历了两个伸展—挤压构造旋回,可划分为4个演化阶段,即早、中侏罗世伸展断陷—坳陷阶段、晚侏罗世—白垩纪挤压坳陷—挤压隆升阶段、古新世(路乐河期)—中新世早期(上油砂山期)整体挤压坳陷与柴西局部拉分弱断陷阶段和中新世晚期(狮子沟期)—第四纪挤压反转阶段。盆地的构造演化控制了烃源岩的分布与演化、圈闭的形成、油气运移与成藏以及油气的保存,进而控制了油气的分布,在此基础上指出了柴达木盆地的勘探方向。     

鄂尔多斯盆地及其邻区关键构造变革期次及其特征

鄂尔多斯盆地为典型的克拉通内盆地,油、气、煤、盐、铀等矿产资源丰富。研究构造运动的期次、序列与性质将为揭示克拉通盆地的成因与演化过程奠定基础,同时也将为探讨多种能源、矿产资源赋存的内在机制提供依据。基于近年来的高精度区域反射地震剖面和深井资料,结合周缘地质露头分析,通过厘定鄂尔多斯盆地的关键构造变革时期,建立了盆地演化的时-空框架。研究表明,鄂尔多斯盆地由下至上发育10个区域不整合面,分别为长城系、蓟县系、震旦系、寒武系、奥陶系、石炭系、三叠系、侏罗系、白垩系和第四系底界不整合面;盆地发育中元古界、寒武系-奥陶系、上石炭统-三叠系、侏罗系、下白垩统和新生界6个构造-地层层序。鄂尔多斯盆地的形成与演化受控于周缘板块构造作用,经历了中元古代早-中期大陆裂解、寒武纪-中奥陶世被动大陆边缘、晚奥陶世主动大陆边缘形成与碰撞造山、晚石炭世-二叠纪末期周缘裂解、中生代早期大型陆内坳陷、中生代中-晚期陆内前陆盆地和新生代周缘断陷等演化过程。鄂尔多斯盆地岩石圈深部的构造作用相对活跃,盆地内部发育中奥陶世、中-晚三叠世、早白垩世与晚中新世4期中酸性、中基性火山活动,其中,早白垩世晚期的火山活动强烈。结合周缘板块构造事件、盆内岩浆活动和盆地沉降-隆升过程分析,鄂尔多斯盆地经历了新元古代、晚奥陶世、中-晚三叠世、晚侏罗世-早白垩世、新生代5个关键构造变革期,这些构造变革期控制了盆地的构造演化和地质结构,对鄂尔多斯盆地的油气分布产生了深远影响。     

库车前陆盆地三叠系层序地层研究

综合分析车前陆盆地三叠系地震，测井，钻井，露头资料，识别出13个层序边界，划分出12个层序和33个体系域，建立两种层序地层学框架模式：（1）早三叠世至晚三叠世黄山街组沉积末期，具有典型前陆盆地挤压深陷特征，层序地层呆模式与内部构成类似于Vail的被动大陆边缘型盆地；（2）晚三叠世塔里奇克组沉积期至白垩纪末期，具有宽缓，伸展的特点，层序地层框架模式及内部地层构成样式有其独特性，层序发育主要受构造运动，古气候及沉积物供给的影响。控制湖平面或基准面变化的主要因素是构造活动，造山运动强烈期是主要的湖进期，构造运动相对静止期是主要的湖退期，气候支序地层格架内的沉积相类型。图4表1参8（何宏摘）／     

位于巨型走滑断裂端部盆地演化的地质模型——以苏丹穆格莱德盆地为例

横跨非洲大陆中部巨型中非断裂带东端的穆格莱德盆地的演化与周邻的大地构造背景密切相关。在早白垩世的演化与大西洋的分阶段张裂密切相关,晚白垩世的演化与印度块体的快速北移有关,新生代的演化主要和红海的扩张有关。盆地的构造演化可划分三大阶段:在早白垩世盆地发育的鼎盛时期,受中非走滑断裂的影响,盆地沉降速率巨大,沉积中心和沉降中心往往不一致;在晚白垩世,盆地为断陷和坳陷型沉积,沉积中心向远离中非断裂带的东南方向迁移。盆地总体的演化具有从走滑型向拉张伸展型转化的特点。在盆地演化的早期,烃源岩和储集岩在靠近中非走滑断裂带附近较发育;在晚期的构造挤压作用下,一方面对已形成的油气藏进行破坏,同时,可造成油气重新分布,形成一些新生的油气藏。在该部位沉降中心和沉积中心往往不一致,这给油气的勘探带来新的困难,因此对这些地区的勘探要十分慎重。在远离中非断裂带的盆地东南部,是晚期沉积和沉降的中心,主力烃源岩演化比较适中,油气成藏期较晚,是寻找具有工业价值油气田的有利部位。