山东东营凹陷南坡地区沙四段纯下亚段湖相碳酸盐岩滩坝发育的控制因素探讨^*   总被引：2，自引：0，他引：2       下载免费PDF全文

宋国奇  王延章  路达  闫瑞萍  杨静 《古地理学报》2012,14(5):565-570

碳酸盐岩滩坝是断陷湖盆中一种重要的沉积类型。文章通过对古气候、古地貌、古物源、古水深和古盐度等因素对碳酸盐岩滩坝形成与分布控制作用进行研究,总结出了“古气候是基础,古地貌和古物源是条件,古水深是关键,古盐度是保障”是东营凹陷南坡地区沙河街组四段纯下亚段碳酸盐岩滩坝的“五古”控制模式。较干旱的温热适中的古气候条件下蒸发作用较强,有利于湖相碳酸盐岩的形成;水下隆起及其斜坡是碳酸盐岩滩坝沉积的有利场所,较低的碎屑岩物源供给指数为碳酸盐岩的发育提供了良好的环境;3～32m左右的古水深是碳酸盐岩发育的主要深度;古盐度为碳酸盐岩的沉积提供了物质保障,在一定程度上控制了白云岩和石灰岩的分布。采用主因素分析法对碳酸盐岩的控制因素进行了排序,古地貌对碳酸盐岩发育的控制作用最大,其次为古物源和古水深,古盐度的控制作用最小。  相似文献   

黄河口凹陷西北部湖底扇的沉积演化及发育模式——以古近纪沙三下亚段为例   总被引：2，自引：1，他引：1  

剧永涛  刘豪  辛仁臣 《东北石油大学学报》2012,(1):8-13,30,7,6

湖底扇是黄河口凹陷古近纪一种重要的沉积类型,扇体储集物性和含油性较好,具有勘探价值.研究黄河口凹陷沙河街组沙三下亚段岩心、测井、地震反射特征,认为A区含油砂岩体为在半深湖—深湖环境形成的2种类型湖底扇沉积.低位域时期发育远岸的深水浊积湖底扇;湖扩域和高位域时期发育由三角洲前缘砂体滑塌进入湖底堆积而成的滑塌浊积湖底扇.从空间分布看,深水浊积扇主要发育在低位域湖盆内二阶断裂的下降盘;滑塌浊积扇主要发育在研究区南部的断裂陡坡带,位于扇三角洲前方,且扇体规模较大,发育时间长.湖底扇的发育受沉积坡折和断裂坡折的控制.由于构造背景、湖平面变化及物源供应不同,湖底扇的位置、规模和形态也不尽相同.  相似文献   

北部湾盆地涠西南凹陷与海中凹陷古近纪沉积关系探讨     

李上卿  牛华伟  郑军  江平  黄建军 《海洋地质译丛》2012,(1):1-6

涠西南凹陷与海中凹陷相邻,油气勘探成果及石油地质条件认识程度不同。通过对地层原始产状的恢复,讨论了涠西南低凸起对两凹陷古近纪沉积环境的阻隔作用,并对古新世和始新世沉积可容空间原型进行了恢复,认为古新世两凹陷局部连通,始新世和渐新世两凹陷全部连通;3号断层作为两凹陷区划边界的一部分,其活动强度控制了沉积可容空间的分布和容积的大小,始新世3号断层活动强度最大,其形成的沉积可容空间也最大,由于两凹陷沉积连通,因此两凹陷始新统生烃能力可以进行类比分析。  相似文献   

Classification and origin of natural gases from Lishui Sag,the East China Sea Basin     

《中国科学D辑(英文版)》2008,(Z1)

Natural gases discovered up to now in Lishui Sag,the East China Sea Basin,differ greatly in gaseous compositions,of which hydrocarbon gases amount to 2%―94%while non-hydrocarbon gases are dominated by CO2.Their hydrocarbon gases,without exception,contain less than 90%of methane and over 10%of C2 heavier hydrocarbons,indicating a wet gas.Carbon isotopic analyses on these hydrocarbon gases showed thatδ13C 1 ,δ13C 2 andδ13C 3 are basically lighter than-44‰,-29‰and-26‰, respectively.The difference in carbon isotopic values between methane and ethane is great,suggesting a biogenic oil-type gas produced by the mixed organic matter at peak generation.δ13C CO2 values of nonhydrocarbon gases are all heavier than-10‰,indicating a typical abiogenic gas.The simulation experiment on hydrocarbon generation of organic matter in a closed gold-tube system showed that the proportion of methane in natural gases produced by terrigenous organic matter in the Lingfeng Formation marine deposit is obviously higher than that in natural gases derived from the aquatic and terrigenous mixed organic matter in the Yueguifeng Formation lacustrine deposit,consequently the proportion of heavier hydrocarbons of the former is remarkably lower than that of the latter.Moreover, δ13C 1 values of natural gases produced by terrigenous organic matter in the Lingfeng Formation marine deposit are about 5‰heavier than those of natural gases derived from the aquatic and terrigenous mixed organic matter in the Yueguifeng Formation lacustrine deposit whileδ13C 2 andδ13C 3 values of the former are over 9‰heavier than those of the latter.Currently the LS36-1 oil-gas pool is the only commercial oil-gas reservoir in Lishui Sag,where carbon isotopic compositions of various hydrocarbon components differ greatly from those of natural gases produced by the Lingfeng Formation organic matter but are very similar to those of natural gases derived from the Yueguifeng Formation organic matter,therefore,natural gases in the LS36-1 oil-gas pool are mainly derived from the Yueguifeng Formation lacustrine source rock rather than the Lingfeng Formation marine or Mingyuefeng Formation coal-measures source rocks.  相似文献   

Controls of faulting on synrift infill patterns in the Eocene PY4 Sag,Pearl River Mouth Basin,South China Sea     

J. Ge  F. Yu  B. G. Jones  W. Tao 《Australian Journal of Earth Sciences》2019,66(1):111-132

Tectono-stratigraphic analysis of the Eocene PY4 Sag, Pearl River Mouth Basin, reveals that the evolution of normal faulting exerted an important control on the basin infill patterns. Seismic, well log and core data jointly indicate the Eocene Wenchang Formation can be subdivided into four third-order sequences that are related to early rift (WSQ1), rift climax (WSQ2–3) and late rift (WSQ4) stages. During the early rift stage, the PY4 Sag was defined by three, small-sized depocentres; it was related to low tectonic subsidence and likely overfilled by footwall-derived fan-delta deposits. The isolated depocentres coalesced and formed a larger and more uniform depocentre during the rift climax stage. Significantly increased tectonic subsidence during the rift climax WSQ2 sub-stage gave rise to prominent deep lake deposition including nearshore subaqueous fans, turbidite fan deposits and good source rocks. Two sediment infill patterns adjacent to boundary fault are developed during the rift climax WSQ3 sub-stage: (i) a more likely sediment balance-filled pattern controlled by the low-angled fault and (ii) a sediment under-filled pattern adjacent to the relatively high-angle boundary fault. The late rift stage was characterised by a waned displacement on the NE-striking fault but an increase in displacement on E-striking rift-related faults; this non-synchronous faulting has led to the sediment overfilled pattern observed in the South Sub-sag but a more sediment balance-fill on the South-western Slope. The variability in the basin infill patterns is suggested to have resulted from the different fault displacement patterns, which are closely linked to the boundary fault angles and possible stress field transitions during the basin evolution. This study may provide potential implications for basin infill evaluations in the Eocene Pearl River Mouth Basin and other similar rift systems.  相似文献   

Paleo-environment and provenance in a lacustrine shallow-water delta-meandering river sedimentary system: insights from the Middle–Upper Jurassic formations of the Fukang Sag of Junggar Basin,NW China     

L. Luo  X. Tan  J. Gluyas  J. Wang  X. Kong 《Australian Journal of Earth Sciences》2019,66(5):699-722

The Middle–Upper Jurassic Shishugou Group in the central Junggar Basin was deposited in a lacustrine shallow-water delta-meandering river sedimentary system. The integrated petrological (thin-section, granularity and heavy minerals analysis), geochemical (trace elements and rare earth elements analysis) and geophysical analyses (well logging and 3D-seismic slice analysis) are used to determine redox conditions, paleoclimate, paleosalinity, provenance and sedimentary evolution extant during deposition of the Shishugou Group: (1) the redox condition changed from a weak anoxic/oxic condition to a strongly oxic condition; (2) the climate changed from humid to hot and arid in the Middle–Late Jurassic, which may have resulted in the lake water having slight–medium salinity; (3) the relatively distant northeastern provenance from the Kelameili Mountain is the most important sediment source; and (4) the south provenance from the Tianshan Mountains (Bogeda Shan) decreases with the development of the sag piedmont, which supplies sediments to the southeastern Fukang Sag. The sedimentary environment changed from a lacustrine shallow-water delta to a meandering river during the deposition of the Shishugou Group. The shallow-water meandering river delta was characterised by pervasive mudstones with oxide colours, thin single-layer sand bodies (1–15?m, mean 3?m), relatively low sand–strata ratios (0.2–0.5) and the absence of progradation, mouth bars and reverse rhythms. The gentle slope is the primary condition necessary for the formation of a shallow-water meandering river delta. Paleo-environment (climate change from warm-humid to hot-arid) and the stable and remote Kelameili Mountain provenance played critical roles in the development and evolution of lacustrine–delta-meandering river sedimentary systems.  相似文献   

中非Muglad盆地Sufyan凹陷现今地层残余结构特征与成因     

黄彤飞  张光亚  刘爱香  史艳丽  王敏  邹荃  许昕  杨志强 《岩石学报》2019,35(4):1225-1237

盆地(或凹陷)结构是由盆地构造与沉积演化决定的,因此分析恢复中非Muglad盆地Sufyan凹陷构造与沉积演化过程对于认识该凹陷现今残余结构具有重要的作用。本文通过对该凹陷现今结构特征描述、地层不整合面识别与剥蚀量恢复以及构造沉降和沉积充填历史恢复,并结合区域构造演化分析,对该凹陷现今结构几何学特征、运动学过程与动力学成因及控油作用进行了研究。结果表明:Sufyan凹陷现今地层剖面主要由第一裂谷作用旋回的沉积构成。该旋回期地层约占凹陷现今沉积地层厚度的79%～81%。凹陷现今残余结构主要受三期裂谷作用差异演化控制,而受晚白垩世挤压剥蚀(厚度介于0～360m之间)的影响较小。造成凹陷三期裂谷旋回差异演化的主要原因是三期伸展应力来源、大小、方向的差异。诱发凹陷第一裂谷旋回期的应力主要来源于由中非剪切带的剪切应力转换的伸展应力。第二裂谷旋回期,中非剪切带运动方向由右旋逐渐转为左旋,造成该凹陷位置的伸展应力场减弱,并逐渐转为挤压状态,使得该演化阶段早期沉积的地层(Darfur群)后期发生反转剥蚀减薄。在该凹陷第三裂谷旋回期,东非裂谷成为非洲大陆新的构造活动区域。受此影响,中非剪切带活动逐渐停止,而红海裂谷张开产生伸展应力场与该凹陷长轴近平行,造成第三期断坳旋回在该凹陷几乎不发育,最终使该凹陷现今早断早衰型残余结构得以形成。该结构控油作用主要体现在主力成藏组合与油气优势运移方向方面。早衰型结构造成了Sufyan凹陷中组合和上组合成藏条件不佳,其下组合Abu Gabra(简称AG,下同)组自生自储自盖型成藏组合为该凹陷的主力成藏组合。挤压反转造成中部构造带形成构造高部位,成为了凹陷油气二次运移的主要指向,是凹陷油气勘探的有利区带。  相似文献   

东濮凹陷盐湖相原油氮/氧化合物分布特征及其应用     

李素梅  徐田武  史权  张云献  吴建勋  柯昌炜 《现代地质》2019,33(6):1137-1150

东濮凹陷盐湖相原油中杂原子化合物研究薄弱。采用高分辨率质谱技术、结合色谱-质谱,对东濮凹陷盐湖相、淡水湖相原油、烃源岩中的含氮、氧化合物进行了检测。结果表明,原油中含有丰富的氮、氧化合物, N₁、O₁和O₂占绝对优势;随成熟度增加,N₁和O₁类化合物相对丰度增加、O₂类化合物相对丰度降低、氮/氧化合物的缩合度增加、烷基侧链碳数范围降低,提出了多项氮、氧化合物的成熟度辅助识别指标,建立了DBE₁₅/DBE₉-N₁和DBE₁₅⁺/DBE₁₄^--N₁与折算镜质体反射率之间的定量关系式。通过对氮、氧化合物的油-油、油-岩对比,认为东濮凹陷盐湖相原油主要来自成熟烃源岩。基于高分辨率质谱的氮、氧化合物具有重要的成熟度评价、油源对比、油气运移示踪的应用前景。  相似文献   

准噶尔盆地玛18井区百口泉组基准面旋回及其对砂体的控制          下载免费PDF全文

卢志远  马世忠  张景  朱健  周恒  王黎  张方  朱越 《高校地质学报》2019,25(2):287

三叠系百口泉组是新疆油田的主要储集层之一。应用高分辨率层序地层学基准面旋回原理,依据4 口井的岩芯资 料、122 口井的录井、测井等资料,对准噶尔盆地玛湖西斜坡玛18 井区百口泉组各级次基准面旋回界面进行了系统分析, 将百口泉组划分为1 个长期基准面旋回的上升半旋回、3 个中期基准面旋回和18 个短期基准面旋回层序。百口泉组下部发 育扇三角洲前缘亚相,上部发育前扇三角洲亚相。基准面旋回内砂体特征研究表明：百口泉组底部,可容纳空间增长速率 与沉积物供给通量的比值远远小于1 （A/S≤1）,水下分流河道砂体大面积连片展布,主要以进积的切叠式为主;百口泉组 中部,随着基准面上升,A/S 增加,砂体以接触式分布;百口泉组上部,河水动力减弱,河道砂体进一步向后退积,发育 远砂坝砂体,砂体以孤立式分布为特征。长期旋回的早中期发育水下分流河道砂体形成了主要的岩性储集砂体;末期湖侵 作用形成的湖泛泥岩为油气圈闭提供了良好的盖层。  相似文献   

Orbital cyclicity in sedimentary sequence and climatic indications of C-O isotopes from Lower Cretaceous in Qingxi Sag,Jiuquan Basin,NW China     

Siding Jin  Haiyang Cao  Hua Wang  Michael Wagreich  Sylvain Richoz 《地学前缘(英文版)》2019,10(2):467-479

Sedimentary deposits of the Lower Cretaceous Xiagou Formation form the most significant potential hydrocarbon reservoirs in the Qingxi Sag, Jiuquan Basin(NW China). Zircon U-Pb ages of the dated basalts at the top of the Xiagou Formation give an isochron age of 115.6 Ma, and the sedimentation interval of the Xiagou Formation was speculated to range from about 125/124 Ma to 115 Ma based on paleontological research and stratigraphic correlation analysis. Here we use GR logging data as a palaeoenvironmental and palaeoclimatic proxy to conduct a detailed cyclostratigraphic study of five selected wells. Power spectra, evolutionary fast Fourier transformation and wavelet analysis all reveal significant sedimentary cycles in the Xiagou Formation. The ratios of cycle wavelengths in these stratigraphic units are 33.82 m : 7.91 m : 3.06 m : 1.79 m, which is similar to the ratio of orbital targets of 20 : 5 : 2 : 1. The ratio of 20 : 5 : 2 : 1 is interpreted as Milankovitch cycles of 405 kyr long eccentricity,100 kyr short eccentricity, 37 kyr obliquity, and 22 kyr precession cycles respectively. A high-resolution astronomical time scale is constructed by tuning the stratigraphy into target curves of orbital cycles respectively. Based on the astronomical time scale, the absolute ages of 55 samples were estimated,which are used for subsequent stable carbon and oxygen isotope stratigraphy analysis. The analysis results of the five studied wells in the Qingxi Sag indicate:(1) a negative trend of δ~(13)C values upwards in the Xiagou Formation, and(2) negative δ~(18)O values with a positive trend upwards. Both relatively heavy values and pronounced covariances of δ~(13)C values and δ~(18)O values indicate an arid-evaporationcontrolled climate during the sedimentary period of the Lower Cretaceous Xiagou Formation, Qingxi Sag, Jiuquan Basin. Moreover, positive covariances of SQK_1g_(2+3) indicate extremely high temperature, and negative covariances of SQK_1g_1 indicate a relatively low temperature.  相似文献