浊积岩和砂质碎屑流岩关键识别标志及辽河盆地岩心实例^*          下载免费PDF全文

杨棵  朱筱敏  刘宇  刘兴周  郭峰 《古地理学报》2020,22(3):483-492

重力流是自然界中广泛存在的一种流体形式,不同学者基于不同切入点往往会提出多种重力流的划分方案。采用浊流和碎屑流的二分方案,对浊积岩和砂质碎屑流岩的沉积特征展开综述和探讨,旨在进一步概括这2类岩石的沉积特征,明确具有指示意义的最典型相标志。研究表明,在野外露头和钻井岩心中,可以通过以下典型特征鉴别浊积岩和砂质碎屑流岩: 砂岩内若发育以正粒序为特征的递变层理,则应该将其认定为浊积岩;若砂岩内发育泥岩撕裂屑、漂浮状泥砾或不含任何层理构造(块状砂岩),则应该将其认定为砂质碎屑流岩。这些特征是鉴别浊积岩和砂质碎屑流岩最可靠的标志。此外,变形层理、爬升波纹交错层理、波状层理、平行纹层、冲刷侵蚀界面、岩性突变界面和槽模等沉积构造也具有一定指示意义,出现这些特征时需要结合沉积背景、岩相的垂向组合关系和地球物理等资料进行综合判断。  相似文献   

内蒙古巴拉格歹地区构造混杂岩带中浊积岩、震积岩特征及意义——以内蒙古哈拉黑等八幅1:5万区域地质调查为例     

张庆奎  杨宾  邵学峰  陈树良  赵明远  吕凤祥 《地质通报》2018,37(9):1731-1735

浊积岩为具有鲍马序列的古海沟沉积,其部分沉积物与古海沟地震密切相关,由于岛弧外弧海沟地质构造复杂,洋板块俯冲及火山岩的喷发,地震活动强烈、频繁,沉积岩在成岩过程不断受到地震扰动,形成具有地震活动特点的震积岩。通过对巴拉格歹地区构造混杂岩带中浊积岩、震积岩的研究,识别出浊积岩系的具递变层理的槽模、沟模等冲刷铸模,包卷层理构造及最顶部黑色粉砂质泥岩段;识别出震积岩系的液化脉、地震震碎角砾岩、滑塌角砾岩、震褶岩-卷曲、纹层状、阶梯状断层构造等,建立并确认浊积岩、地震岩识别标志,恢复古地理构造环境,认为原划分的大石寨组应该解体,应为一套弧前盆地古海沟浊积岩沉积。结合浊积岩中的火山岩、基性岩及区域上化石山发现的超基性岩,初步确认,在测区浊积岩与岛弧火山岩、洋壳沉积物受板块碰撞拼接作用,由一系列逆冲断裂将上述各种块体构造就位在一起,形成构造混杂岩,为二连-贺根山缝合带在本区东延问题提供了资料。  相似文献   

转换大陆边缘盆地深水浊积砂岩油气成藏差异性研究     

孔令武  赵红岩  梁建设  程涛  王嘉  赵佳奇  喻英梅 《沉积学报》2022,40(1):244-254

深水浊积砂岩油气藏是当今世界油气勘探的热点领域。基于地震、钻井、地球化学等资料,系统分析了西非北段科特迪瓦盆地深水浊积砂岩油气成藏的差异性。研究表明,科特迪瓦盆地经历了裂陷期（早白垩世）和漂移期（晚白垩世—现今）两大构造演化阶段,漂移期发育塞诺曼—土伦阶优质海相烃源岩,裂陷期发育阿普特—阿尔布阶湖相烃源岩。漂移期层系为盆地的主力勘探层系,发育两种类型的浊积砂岩油气藏。塞诺曼—土伦阶浊积砂岩油气藏为典型的“砂体运移、自生自储、源内成藏”的油气成藏模式,其油气主要来源于塞诺曼—土伦阶烃源岩,广泛分布的浊积砂岩是油气运移的主要路径,烃源岩的生、排烃期决定了油气成藏时期,是否发育有效烃源岩是该类油气藏成藏的主控因素。圣通—马斯特里赫特阶浊积砂岩油气藏为典型的“断裂运移、下生上储、源外成藏”的油气成藏模式,其油气主要来源于深部裂陷期阿普特—阿尔布阶湖相烃源岩,断裂是油气运移的主要路径,断裂的活动控制了油气的运移和成藏时期,是否发育油源断裂是该类油气藏成藏的主控因素。  相似文献   

Distribution Patterns of Calcite Cement in the Turbidite Sandstones of the Shahejie Formation in the Dongying Depression, Eastern China     

ZHANG Yongwang  QU Zhengyang 《《地质学报》英文版》2022,96(3):1041-1056

Calcite cements are volumetrically dominant among the most diagenetic constituents in turbidite sandstones of the Paleogene Shahejie Formation in the Dongying Depression. The results show carbonate cements mainly occur in three phases: Calcite I (pre-compaction), Calcite II (post-compaction) and ankerite in the turbidite sandstone. The isotopic composition of Calcite I and Calcite II range from ?4.3‰ to 4.4‰, ?3.5‰ to 4.3‰ PDB, respectively, suggesting that the calcite cements are mainly derived from the interbedded shales. The early calcite cement precipitated from the mixing of lacustrine and meteoric waters at 38–69°C. The late-phase calcite precipitated from pore waters modified by water-rock interactions at 64–126°C. Two distribution patterns of calcite cements can be identified, depending on their position within the sandstone. The peripheral cementation of the sandstones is near the sand-shale contact. The development of cement is controlled by sandstone thickness and the properties of the interbedded shale. For scattered cementation, the distribution of the calcite cement is not controlled by the sand-shale contact. Calcite cement was preferentially distributed in coarse-grained sandstones, indicating that sandstones with high original permeability are the preferred pathway for the migration of early diagenetic fluids.  相似文献   

内蒙古元宝山小建昌营子地区三面井组沉积环境     

陈井胜  邢德和  刘淼  张德军  马国祥  杨佳林  张志斌 《世界地质》2015,34(4):1013-1023

在进行内蒙古1∶5万区域地质调查工作中,对内蒙古赤峰元宝山镇小建昌营子一带的下二叠统三面井组砂岩进行了粒度分析。结果表明,萨胡成因环境判别值为10.66~10.76,沉积环境为河流相或三角洲相;弗里德曼粒度参数判别为陆相河砂沉积;浊流C-M判别图解显示沉积环境介于三角洲与浊流沉积之间。三面井组总体为一套河流相-三角洲前缘滑塌浊积扇沉积。滑塌浊积扇一般发育于深湖、半深湖区,结合本地区三面井组地层中缺乏海相碳酸盐岩沉积,综合认为本区的三面井组形成于河流-湖泊三角洲环境。  相似文献   

鄂尔多斯盆地陇东地区长7段致密砂体重力流沉积模拟实验研究   总被引：2，自引：0，他引：2  

杨华  牛小兵  罗顺社  冯胜斌  吕奇奇 《地学前缘》2015,22(3):322-332

致密砂岩目前已成为中国油气勘探开发的重点领域。以鄂尔多斯盆地陇东地区长7段为代表的典型致密砂岩主要发育辫状河三角洲和重力流沉积砂体,其中重力流沉积砂体具有很大的勘探开发潜力。在区域构造、古气候、古地貌和沉积体系等研究基础上,应用沉积模拟技术,再现了研究区长7段重力流沉积砂体形成过程及其主要控制因素,在实验条件下,半深湖深湖区的沉积微相类型主要包括砂质碎屑流、浊积岩、深湖泥等。实验研究表明,影响重力流沉积砂体的形成及其演化的主要控制因素有：(1)泥砂含量决定了重力流的沉积类型;(2)湖盆底形控制重力流的砂体展布;(3)湖水位及流速决定重力流的沉积厚度及规模;(4)多物源交汇决定重力流的横向连通。并通过实验结果对比分析,预测了有利储集层分布区域。综合陇东地区原始地质模型和实验模拟成果,建立了沉积模拟实验条件下陇东地区三叠系长7段沉积模式。  相似文献   

First record of contourites from Lower Devonian Liptrap Formation in southeast Australia   总被引：2，自引：0，他引：2  

YuanSheng Du  G. R. Shi  YiMing Gong 《中国科学D辑(英文版)》2008,51(7):939-946

Typical contourite deposits associated with submarine turbidite fan deposits are recognized for the first time from the Lower Devonian Liptrap Formation at Cape Liatrap, Victoria in southeast Australia. The contourites are well integrated within the turbidite fan deposits and are characterized by thin (5-8 cm), lenticular, well-sorted coarse-grained siltstones to fine-grained sandstones with current-ripples and cross beddings. The palaeocurrent directions of the turbidite fan and contourites are perpendicular to each other, with the former directed generally westward while the latter varying from 165° to 190° southward. In view of the facies types and architecture, we suggest that the turbidite fan was developed at the base of a westward inclined palaeo-slope, at the front of which the contourites were deposited as a result of southward flowing deep-sea contour (geostrophic) currents. The depositional setting inter- preted for the Liptrap Formation thus may provide a provisional model for the Lower Devonian conti- nental slope and abyssal basin environment in the southeastern part of the Melbourne Trough.  相似文献   

Kema terrane: A fragment of a back-arc basin of the early Cretaceous Moneron–Samarga island-arc system, East Sikhote–Alin range, Russian Far East     

Alexander I.  Malinovsky  Vladimir V.  Golozoubov  Vladimir P.  Simanenko  Ludmila F.  Simanenko 《Island Arc》2008,17(3):285-304

Abstract The Kema terrane is a suite of Barremian(?)–Aptian to Albian volcano-sedimentary rocks of Sikhote–Alin that are interpreted as deposits of the back-arc basin of the Moneron–Samarga island-arc system. Compositional features of the different-type deposits indicate a near-slope depositional environment influenced by volcanic processes. Studies of slump fold orientation testify to the accumulation of material from southeast to northwest by gravitational sliding. Compositional characteristics of terrigenous rocks suggest the major provenance for detrital material was an ensialic volcanic island arc. Petrochemical characteristics of basaltic rocks indicate that the formations studied were confined to the back part of the arc.  相似文献   

Tectonics and sedimentation around Kashinosaki Knoll: A subducting basement high in the eastern Nankai Trough     

Toshihiro  Ike  Gregory F.  Moore  Shin'ichi  Kuramoto  Jin-Oh  Park  Yoshiyuki  Kaneda  Asahiko  Taira 《Island Arc》2008,17(3):358-375

Abstract   When seamounts and other topographic highs on an oceanic plate are subducted, they cause significant deformation of the overriding plate and may act as asperities deeper in the seismogenic zone. Kashinosaki Knoll (KK) is an isolated basement high of volcanic origin on the subducting Philippine Sea Plate that will soon be subducted at the eastern Nankai Trough. Seismic reflection imaging reveals a thick accumulation of sediments (∼1200 m) over and around the knoll. The lower portion of the sedimentary section has a package of high-amplitude, continuous reflections, interpreted as turbidites, that lap onto steep basement slopes but are parallel to the gentler basement slopes. Total sediment thickness on the western and northern slopes is approximately 40–50% more than on the summit and southeastern slopes of KK. These characteristics imply that the basal sedimentary section northwest of KK was deposited by infrequent high-energy turbidity currents, whereas the area southeast of KK was dominated by hemipelagic sedimentation over asymmetric basement relief. From the sediment structure and magnetic anomalies, we estimate that the knoll likely formed near the spreading center of the Shikoku Basin in the early Miocene. Its origin differs from that of nearby Zenisu Ridge, which is a piece of the Shikoku Basin crust uplifted along a thrust fault related to the collision of the Izu–Bonin arc and Honshu. KK has been carried into the margin of the Nankai Trough, and its high topography is deflecting Quaternary trench turbidites to the south. When KK collides with the accretionary prism in about 1 My, the associated variations in sediment type and thickness around the knoll will likely result in complex local variations in prism deformation.  相似文献   

Reconstructing paleoenvironment,eruption mechanism and paleomorphology of the Pliocene Pula maar, (Hungary)     

K. Németh  K. Goth  U. Martin  G. Csillag  P. Suhr 《Journal of Volcanology and Geothermal Research》2008

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