波斯湾海域古生界胡夫组沉积特征与成藏规律

波斯湾海域古生界蕴藏着巨大的天然气资源。从区域构造演化出发,对该区古生界胡夫组的沉积特征进行分析,建立了"大型缓斜坡碳酸盐岩台地"沉积模式,提出了该区古生界"源-相-势"复合控藏的成藏规律,并指明了下一步勘探方向。研究表明,波斯湾海域胡夫组主要发育台地与台地边缘相区,从波斯湾西北部向东南部依次发育局限—蒸发碳酸盐岩台地、开阔碳酸盐岩台地、台地边缘浅滩—生物礁,纵向上主要为灰岩、白云岩和膏盐的互层沉积。开阔碳酸盐岩台地、台地边缘浅滩—生物礁为有利储层发育相带。波斯湾海域志留系古赛巴段热页岩烃源灶分布及规模控制着胡夫组油气分布与资源规模。胡夫组沉积相带控制油气平面富集区,膏盐盖层控制油气藏纵向与平面分布。热页岩生烃灶周围的低势能古基底高与盐拱构造是古生界主要的油气聚集带,同时,储层物性、油气运移与保存条件是古生界油气成藏的关键。根据资料分析,波斯湾海域南海湾盐次盆胡夫组发育大量盐拱背斜圈闭,且志留系古赛巴段烃源岩与胡夫组圈闭叠合性好,成藏条件优越。该盐拱构造带预测资源量巨大,为波斯湾海域古生界有利勘探方向。     

下刚果盆地北部海域海相碳酸盐岩沉积储层特征

西非下刚果盆地为一典型被动大陆边缘含盐盆地,下刚果盆地北部海域在白垩系海相碳酸盐岩层系获得丰富油气发现。研究区海相碳酸盐岩领域油气勘探面临的核心瓶颈问题,即白垩系碳酸盐岩的沉积模式、演化规律、储层特征以及沉积储层发育控制因素。综合钻井、地震、区域地质等资料,分析认为自下向上相对海平面的上升控制了沉积演化,沉积体系演化模式为浅海碳酸盐岩台地→浅海混积陆棚→半深海-海底扇。下刚果盆地碳酸盐岩储层展布在纵向及平面上均可以划分为内中外3个储层发育带,碳酸盐岩储层最主要发育于下白垩统Albian阶下Sendji组。该时期研究区整体发育浅海碳酸盐岩混积缓坡台地沉积体系,沉积亚相可进一步划分为混积滨岸、后缓坡、浅水缓坡以及深水缓坡4种类型,其中浅水缓坡亚相颗粒滩微相与后缓坡亚相台内浅滩、砂质浅滩微相储层最为发育。碳酸盐岩储层岩性组合主要包括颗粒灰岩、砂岩、砂质灰岩、白云岩4种类型;储层发育主要受沉积相带的控制,并受成岩作用的影响。     

下扬子-南黄海二叠纪岩相古地理特征及油气勘探启示

以二叠系为研究对象,基于野外露头、钻井资料和地震资料,以沉积相分析为核心,以组为单位编制了下扬子-南黄海二叠纪岩相古地理图,并在此基础上,预测有利烃源岩和储层分布,分析二叠系勘探潜力及勘探方向。研究结果表明:下扬子地区二叠纪为稳定的被动大陆边缘型构造背景,其古地理特征总体呈现的地势为沿NE-SW向展布的轴部低、西北及东南两侧较高的沉积面貌和格局,主要发育三角洲相、滨岸-沼泽相、局限台地相、开阔台地相和斜坡-盆地相等主要优势相;根据烃源岩与岩相古地理之间的对应关系,推测龙潭组煤系烃源岩主要发育于下扬子陆区的安徽东南部到江苏东南部、海区的南黄海盆地中部,综合评价其有机质丰度高、平面分布稳定、厚度大,是二叠系重要的烃源岩发育层段;指出崂山隆起的东南部和东部紧邻生烃中心,三角洲储层发育,油气运移条件优越,晚期保存条件好,是有利勘探靶区。     

肯基亚克油田石炭纪孤立碳酸盐台地边缘的储层特征及分类评价

碳酸盐岩台地是海相碳酸盐岩储层发育的主要环境之一.通过对滨里海盆地东缘肯基亚克油田石炭纪孤立碳酸盐台地储层的沉积和成岩特征分析以及储层预测研究,指出孤立碳酸盐岩台地边缘相带窄,相变快,储层质量明显受沉积和成岩作用共同控制;其中台地边缘礁滩相属浅水高能沉积,成岩作用过程中又经历了较强烈的白云岩化、溶蚀等有利成岩作用的改造...     

礼乐盆地碳酸盐岩时空分布特征及构造意义

对碳酸盐岩(台地与生物礁)的研究具有重要的油气地质意义和科学价值。渐新世以来, 礼乐盆地及周缘开始了大规模的碳酸盐建造, 至今还有一定规模生物礁持续发育。文章通过拖网约束、井震对比和地震相类比方法对礼乐盆地周缘碳酸盐岩的发育特征、构造背景和时空分布规律进行系统研究。结果表明, 礼乐盆地主要发育孤立、前隆、掀斜断块型台地及生物礁。碳酸盐岩时空发育特征为: 1) 渐新世—早中新世以构造前隆和掀斜断块控制的开阔台地为主, 生物礁零星发育; 2) 早中新世—中中新世表现为大量孤立台地和生物礁; 3) 中中新世之后, 发生台地和礁的淹没, 盆地内主要发育点礁。结合构造背景和重磁特征分析表明, 古隆起、掀斜断块、前隆迁移和岩浆活动为控制礼乐盆地不同时期碳酸盐岩发育的主要构造要素。现今礼乐盆地及周缘大量生长的珊瑚礁, 主要发育在上新世—更新世岩浆活动形成的海山之上。     

书海拾贝

普光、元坝碳酸盐岩台地边缘大气田勘探理论与实践郭旭升郭彤楼著科学出版社出版本书以川东北地区普光、元坝海相大气田勘探成果和认识为基础,系统阐述了川东北地区二叠系一三叠系台地边缘礁滩相沉积、储层特征,深层、超深层优质储层识别及预测技术、方法、多旋回构造运动下油气成藏与富集规律,并详细介绍了普光、元坝大气田发现、探明历程和气田特征,总结了大气田勘探的启示。本书论述深入,不仅是对普光、元坝大气田典型实例的解剖,同时也系统地提供了研究超深层碳酸盐岩台地边缘礁滩相气田的思路和方法。     

南海西北深水区中新世碳酸盐台地类型及控制因素

开展西沙海域碳酸盐台地识别及模式总结,不仅具有油气勘探指导意义,而且能丰富碳酸盐岩沉积学理论。基于高分辨率三维、区域二维地震资料,利用古地貌分析,结合碳酸盐岩沉积学类比,确定了南海西北深水区碳酸盐台地类型及展布,分析了其演化过程。认为南海西北深水区中中新世开始发育碳酸盐台地,据构造背景(Ⅰ级)、地理位置(Ⅱ级)将其划分为离岸碳酸盐台地(中中新世)和孤立碳酸盐台地(晚中新世)两大类,据镶边性(III级)和坡度(IV)进一步细分为:离岸台地镶边岛架、离岸台地缓坡、离岸台地陡坡,孤立台地镶边岛架、孤立台地缓坡、孤立台地陡坡等亚类。南海西北部台地经历了由西向东的迁移过程。古地貌和海平面变化是该地区碳酸盐台地生长、持续、消亡的两大主控因素,陆坡隆起控制碳酸盐台地发育范围、规模和迁移方向;凸起控制碳酸盐台地类型、相带和迁移速度;半地堑作为外源容纳空间和输出通道而保证了碳酸盐台地发育的"水清"环境;台地边缘形态决定碳酸盐台地高能相带的分布、类型和规模。海平面上升导致碳酸盐台地由西向东退积,台地面积减小,环礁发育程度趋向成熟。     

贺兰坳拉谷奥陶纪岩相古地理

通过大量野外地质工作,结合测井资料,分析认为,贺兰坳拉谷以浅海碳酸盐沉积为主,其次可见碎屑岩、火山碎屑岩等,以碳酸盐岩占绝对优势.主要的碳酸盐岩类型为泥晶灰岩、泥质灰岩、鲕粒灰岩、竹叶状灰岩及晶粒白云岩、泥质白云岩,局部地区可见叠层石灰岩及云斑灰岩等.泥云坪、局限台地、开阔台地、浅海陆棚、海底扇等为典型沉积相类型.贺兰...     

南黄海崂山隆起石炭系-下二叠统海相碳酸盐岩叠前三参数反演储层预测

崂山隆起为南黄海盆地的构造稳定区,中-古生代海相地层存在较好的油气前景,但其构造复杂,地震资料信噪比低等缘故制约了油气勘探进程。该文采用类比方法,运用相同沉积演化历史环境的四川盆地测井和地震资料作为研究样本,分析碳酸盐岩储层测井和地震响应特征,建立南黄海古生界海相碳酸盐岩地震相和储层分布特征。根据简化的Zoeppritz方程引入岩石弹性模量,对南黄海崂山隆起地震测线进行叠前三参数反演,获得相对密度、体积模量和剪切模量数据体,沿着研究目的层提取以上3种属性参数进行3D聚类分析,再反投到地震剖面上获得地震相,在地震相的控制下再次进行聚类交互,分别获得各地震相下有利储层的空间分布情况。通过分析,南黄海崂山隆起下二叠世和石炭纪时期主要发育局限台地相、开阔台地相、台地边缘浅滩相和台地边缘生物礁相4种沉积相,相应发育岩溶型白云储层和礁、滩相储层,储层受沉积环境影响较大,但后期的构造运动对储层孔隙也有一定的改造作用。     

南黄海盆地南部坳陷下三叠统沉积相

南黄海盆地是下扬子地块向海洋的延伸,中三叠世以前为统一的海相盆地。目前陆上地区下三叠统沉积相展布已经基本搞清,但是海区研究程度较低。结合陆上下扬子地块的研究成果,通过实际的钻井、地震资料分析,开展了南黄海盆地南部坳陷下三叠统沉积相研究,结果表明:研究区下三叠统沉积体系呈NE向展布,由NW向SE水深逐渐变浅,依次发育台缘斜坡相、开阔台地相和局限台地相;局限台地相暗色泥岩和泥质灰岩发育,为有利的烃源岩。     

滨里海盆地科尔占地区石炭系沉积相

科尔占地区位于滨里海盆地阿斯特拉罕-阿克纠宾斯克隆起带东南部的比伊克扎尔次级隆起上，该地区广泛发育下二叠统孔谷组盐岩，以盐岩沉积为界，它将整个剖面划分为盐上层系（以碎屑岩为主的含油气层系）和盐下层系（以碳酸盐岩为主的含油气层系）两个大的含油气层系，石炭系为盐下层系中主要的含油气层系之一。通过对研究区唯一的盐下井K井岩屑及其薄片的详细观察，并结合该井测井资料，分析了石炭系的沉积特征，并对其沉积相进行了划分与描述。K井石炭系主要发育3种类型沉积相，分别为深水浊积扇相、斜坡相和台地相，其中深水浊积扇相可进一步划分为内扇、中扇和外扇3个亚相，台地相划分为滩间洼地和台内滩2个亚相。利用K井钻探结果，结合区域资料，初步预测出科尔占地区早石炭世和中石炭世末期沉积相带的平面分布特征。     

川东北宣汉盘龙洞长兴组生物礁剖面沉积相分析

结合区域构造、地层概况、岩相古地理等方面的背景资料,对宣汉盘龙洞上二叠统长兴组生物礁地层剖面进行了观测描述。通过室内镜下岩石薄片鉴定分析,识别出主要岩石类型为礁灰岩、礁云岩、生屑灰岩、颗粒灰岩及晶粒白云岩。根据露头观察和室内镜下岩石薄片鉴定分析,结合岩石学、古生物等沉积相标志的研究,认为该剖面发育开阔台地、台地边缘生物礁和台地边缘浅滩三种沉积相类型,其中台地边缘生物礁发育,可进一步识别出礁基、礁核和礁前亚相,礁核以骨架礁和障积礁为主;台地边缘浅滩进一步划分为粒屑滩、鲕粒滩等亚相。初步总结出了该剖面的沉积相模式,并对该剖面的沉积演化序列和识别标志进行了讨论。     

湖北兴山大峡口二叠系剖面沉积相分析

在大量前人研究的基础上，通过野外实测，运用沉积相分析方法，结合露头层序地层学、生物地层学、储层成岩作用等方面研究，初步对湖北兴山大峡口二叠系剖面进行了沉积相分析研究，认为该剖面由下至上可划分为两个沉积体系单元，即碳酸盐缓坡沉积体系（相）和碳酸盐台地沉积体系（相）。同时，初步总结出了该剖面的沉积相模式。海平面的升降变化是控制该区沉积相发育和分布的主要因素。     

Oolitic shoal complexes characterization of the Lower Triassic Feixianguan Formation in the Yuanba Gas Field,Northeast Sichuan Basin,China

The Yuanba Gas Field is the second largest natural gas reservoir in the Sichuan Basin, southwest China. The vast majority of the natural gas reserve is from the Permian Changhsingian reef complexes and Lower Triassic Feixianguan oolitic shoal complexes. To better understand this reservoir system, this study characterizes geological and geophysical properties, spatial and temporal distribution of the oolitic shoal complexes and factors that control the oolitic shoals character for the Lower Triassic Feixianguan Formation in the Yuanba Gas Field. Facies analysis, well-seismic tie, well logs, seismic character, impedance inversion, and root mean square (RMS) seismic attributes distinguish two oolitic shoal complex facies – FA-A and FA-B that occur in the study area. FA-A, located in the middle of oolitic shoal complex, is composed of well-sorted ooids with rounded shape. This facies is interpreted to have been deposited in shallow water with relatively high energy. In contrast, FA-B is located in flanks of the oolitic shoal complex, and consists of poorly sorted grains with various shape (rounded, subrounded and subangular). The oolitic shoal complexes were mainly deposited along the platform margin. From the early Fei 2 Member period to the late Fei 2 Member period, the oolitic shoals complexes on the platform margin gradually migrated from the southwest to the northeast with an extent ranging from less than 100 km²–150 km² in the Yuanba Gas Field. The migration of oolitic shoals coincided with the development of a series of progradational clinoforms, suggesting that progradational clinoforms caused by sea-level fall maybe are the main reason that lead to the migration of oolitic shoals. Finally, this study provide an integrated method for the researchers to characterize oolitic shoal complexes by using well cores, logs, seismic reflections, impedance inversion, and seismic attribute in other basins of the world.     

Linking early diagenesis and sedimentary facies to sequence stratigraphy on a prograding oolitic wedge: The Bathonian of western France (Aquitaine Basin)

To improve the understanding of the distribution of reservoir properties along carbonate platform margins, the connection between facies, sequence stratigraphy, and early diagenesis of discontinuities along the Bathonian prograding oolitic wedge of the northeastern Aquitaine platform was investigated. Eight facies are distributed along a 50 km-outcropping transect in (1) toe-of-slope, (2) infralittoral prograding oolitic wedge, (3) platform margin (shoal), (4) open marine platform interior, (5) foreshore, and (6) terrestrial settings. The transition from shallow platform to toe-of-slope facies is marked in the field by clinoforms hundred of meters long. Carbonate production was confined to the shallow platform but carbonates were exported basinward toward the breakpoint where they cascaded down a 20–25° slope. Ooid to intraclast grainstones to rudstones pass into alternating marl-limestone deposits at an estimated paleodepth of 40–75 m. Three sea-level falls of about 10 m caused the formation of discontinuities corresponding to sequence boundaries. Along these discontinuities, erosional marine hardgrounds formed in a high-hydrodynamic environment at a water depth of less than 10 m, displaying isopachous fibrous cements and meniscus-type cements. The cements pass landward into meniscus and microstalactitic forms along the same discontinuities, which are characteristic of subaerial exposure. During the deposition of transgressive systems tracts, carbonate accumulation remained located mostly on the shallow platform. Energy level increased and carbonates were exported during the deposition of highstand systems tracts forming the infralittoral prograding oolitic wedge. During the deposition of lowstand systems tracts, carbonate production fell to near zero and intraclast strata, derived from the erosion of hardgrounds on the shallow platform, prograded basinward. Early diagenetic cements are related exclusively to discontinuities that are not found within the prograding wedge because of the continuous high sedimentation rate under lower hydrodynamic conditions. This absence of early cementation within the infralittoral prograding oolitic wedge was conducive to porosity conservation, making such features good targets for carbonate reservoir exploration. This study proposes a novel sequence stratigraphy model for oolitic platform wedges, including facies and early diagenesis features.     

厄瓜多尔Oriente盆地南部区块沉积特征

通过构造演化和地层发育特征分析,将厄瓜多尔Oriente盆地南部区块Napo组划分为4个层序。根据岩心中的潮汐层理、羽状交错层理、冲洗交错层理、具有大量贝壳等特征,识别研究区具有潮坪沉积环境。针对其沉积坡度缓,碎屑岩和碳酸盐岩互层沉积的特点,建立了缓坡混积陆棚边缘的沉积相模式,认为Oriente盆地南部区块Napo组发育有海岸平原、潮坪、局限台地和混积陆棚相。相序的垂向组合和平面迁移受海平面升降的控制,指出潮坪砂岩主要出现在各层序的陆架边缘体系域,水下浅滩砂岩出现在海侵体系域。从沉积角度看,潮汐水道砂体是最好的储层砂体。     

An inland facies-controlled eogenetic karst of the carbonate reservoir in the Middle Permian Maokou Formation,southern Sichuan Basin,SW China

Carbonate karst is one of the research highlights in the field of carbonate reservoir geology. Here, we report on a new type of karst formed in the Middle Permian Maokou Formation, southern Sichuan Basin, SW China, i.e., inland facies-controlled eogenetic karst, which is different from the previously defined telogenetic karst. This karst is eogenetic as the formation was buried at shallow depths prior to being subaerially exposed for a period of 7–8 Myr, in the paleo-continental region of the Upper Yangtze Uplift. Subaerial exposure may have been caused by a sea level regression during the Tungwu Orogeny, which gave rise to a depositional hiatus over a broad area. The top of the Maokou Formation is commonly marked by a weathered crust and an unconformable relationship with overlying layers. Below the surface, the Maokou Formation contains sediments deposited by an underground drainage. The geological setting can be inferred from an inland karst far from coastline. The subsurface karst interval consists mainly of coarse-grained limestone and micrite, with the former occurring in shoal facies deposited in a high-energy depositional environment, and the latter in non-shoal facies deposited in a low-energy environment. Both of them were interbedded with in variable thicknesses. The coarse-grained limestone layers with high porosity and permeability acted as inception horizons, more favourable for the development of karst than the micritic layers with low porosity and permeability. Therefore, in places where both coarse-grained limestone and micrite are present, the karst is considered to be facies-controlled. The primary permeability of the coarse-grained limestone, combined with the permeability provided by faults and fractures, provides sufficient channels for karst water. Formation of the karst system was characterized by contemporaneous development at multiple levels, as controlled by the stratigraphic position of coarse-grained shoal facies. The karst reservoir therefore developed in both karst highland and karst transitional zone (area between the karst highland and karst basin). According to this model of karstification, hydrocarbon exploration should focus on karst highlands located on palaeohighs and in synclines located far from fault zones.     

Impact of strong easterly trade winds on carbonate petroleum exploration - Relationships developed from Caicos Platform,southeastern Bahamas

Brisk, persistent easterly trade wind influences define Holocene patterns of carbonate sedimentation across the Caicos Platform (southeastern Bahamas). Resultant predictive sedimentary facies models based on trade wind influences are more widely applicable to the exploration for subsurface carbonate plays than are existing models based on the northern Bahamas facies patterns, which are characterized by gentle trade winds and strong platform-margin-related oceanic processes (swells and tidal currents). The Caicos Platform relationships may be more applicable because many ancient shallow carbonate depositional environments were within the trade wind belts and commonly within broad intracratonic seas that were little influenced by oceanic processes.The grainstone-dominated Caicos Platform exhibits reservoir potential over much of its surface, in contrast to northern Bahamian platforms, where oceanic tidal currents or swells and gentle easterly trade winds confine higher energy environments with reservoir potential to platform margins. Strong easterly trade winds across Caicos Platform promote widespread Holocene platform-interior oolitic, skeletal and grapestone grainstone bodies on this platform. Orientations of ooid sand bodies vary depending on preexisting topography, water depth and bottom energy. Shallow subtidal ooid sand shoals orient parallel to these winds. Ooid sands developed along older shorelines orient parallel to the shorelines but prograde perpendicular into these winds. Deeper platform-interior oolitic sands exist as widespread, sheet-like deposits. These trade winds allow reefs and ooids to coexist in many settings, permit isolated linear reefs to flourish on certain leeward platform margins, and promote effective off-bank transport of carbonate sands that create onlapping grainstone wedges. These relationships are very applicable to the rock record.Strong trade wind influences, such as seen on Caicos Platform, better explain the occurrence of Cretaceous reef and/or oolitic grainstone reservoirs developed well in from platform margins (Fairway Field in East Texas; Black Lake Field in Louisiana) than do existing northern Bahamian models. Depositional models based on conditions in the northern Bahamian models would predict low-energy facies in these platform-interior settings. A trade-wind-driven depositional model, characterized by strong persistent easterlies, also better explains the origin of the onlapping wedge of skeletal grainstones at Poza Rica oilfield in Mexico.The Caicos Platform easterly trade-wind-driven depositional model should generally apply to any ancient shallow carbonate environment that developed 5–22° north or south of the paleoequator, whether or not a platform margin was near by. Future carbonate exploration or exploitation should always factor in not only geological age, but also physiographic, latitudinal and climatic setting at a global and local scale.     

青藏高原羌塘盆地晚侏罗世索瓦期沉积特征研究

为推进我国石油工业发展丰富石油地质理论,根据野外露头及室内分析化验资料,建立8种相标志,识别出索瓦期沉积相类型有：台地相、台地边缘相、盆地相和海陆过渡相、湖泊相。受北部拉竹龙-金沙江缝合带、中央隆起带和南部班公湖-怒江缝合带的影响,沉积相呈近东西向展布,具南北分带的特点。文章分析了索瓦期的沉积特征,总结了该期的沉积模式。根据研究区的生物特征和沉积特征,推断当时气候是温暖、半干旱的。综合分析认为,索瓦组是羌塘盆地很有潜力的油气勘探目的层,其与上覆雪山组地层可构成有利的含油气组合;而双湖-多涌地区是首选的含油气有利区带。