Overview of the MITI Nankai Trough Wells: A Milestone in the Evaluation of Methane Hydrate Resources   总被引：4，自引：0，他引：4  

Yoshihiro Tsuji    Hisashi Ishida    Masaru Nakamizu    Ryo Matsumoto  Satoshi Shimizu 《Resource Geology》2004,54(1):3-10

Abstract. Bottom-simulating reflectors suggestive of the presence of methane hydrates are widely distributed below the ocean floor around Japan. In late 1999, drilling of the MITI Nankai Trough wells was conducted to explore this potential methane hydrate resource and a Tertiary conventional structure. The wells are located in the Northwest Pacific Ocean off Central Japan at a water depth of 945 m. A total of six wells were drilled, including the main well, two pilot wells, and three post survey wells at intervals of 10–100 m. All wells except the first confirmed the occurrence of hydrates based on logging-while-drilling, wire-line logging and/or coring using a pressure and temperature coring system in addition to conventional methods. Based on the various well profiles, four methane hydrate-bearing sand-rich intervals in turbidite fan deposits were recognized. Methane hydrates fill the pore spaces in these deposits, reaching saturation of up to 80 % in some layers. The methane hydrate-bearing turbiditic sand layers are less than 1 m thick, with a total thickness of 12–14 m. The bottom depth of high hydrate concentration correlates well with the depth of the bottom-simulating reflector. Based on these exploration results, the Japanese government inaugurated a 16-year methane hydrate exploitation program in 2001.  相似文献   

1∶5万区调海底扇填图方法的实践——以川西北壤塘地区三叠系西康群为例     

梁斌  王大可  朱兵  陈明  张清洪 《四川地质学报》2002,22(4):193-197

在川西北壤塘地区三叠系西康群海底扇填图实践的基础上 ,从海底扇的沉积特征入手 ,对填图中存在的问题及区调方法、内容进行了分析与探讨 ,提出了岩相—基本层序—组 (地层 )的海底扇填图新方法。  相似文献   

洼陷中浊积岩沉积特征及油气富集规律研究   总被引：13，自引：1，他引：13       下载免费PDF全文

严进荣  陈东  郭勤涛  丘东洲 《沉积与特提斯地质》2002,22(3):19-24

随着油气勘探的不断深入，我国东部地区主要含油气盆地勘探的主要目标逐渐转为一些较复杂的隐蔽油气藏，尤其是盆内的次级洼陷，已成为勘探的重要地区。多年的勘探实践表明，对于我国东部的陆相箕状盆地，洼陷中含油气是必然规律。在洼陷内最重要的油藏类型是砂体岩性与构造—岩性油藏，并且绝大多数为浊流成因。本文以山东济阳坳陷与昌潍坳陷的德南、牛庄、利津、博兴等几个洼陷为例，介绍洼陷生油条件的地震研究方法与三角洲—浊积扇体系中浊积岩发育区的沉积特征、油气富集规律及地震综合研究方法。  相似文献   

深水浊积岩层序地层学研究中碳氧同位素的应用——以湖南大庸田坪剖面为例   总被引：1，自引：0，他引：1       下载免费PDF全文

陈明  万方  蒲心纯 《沉积与特提斯地质》2002,22(4):55-60

笔者通过海平面变化曲线与碳氧同位素曲线比较，发现两者曲线基本吻合，碳同位素曲线显示的海平面变化更接近露头层序地层的海平面变化；氧同位素曲线与露头层序海平面变化大体一致。局部出现相反结论。碳同位素曲线对沉积环境变化较氧同位素曲线更敏感。通过两者曲线研究，说明运用稳定同位素曲线变化可作为浊积岩层序地层学研究的一个研究手段。  相似文献   

广西丹池盆地泥盆系浊积岩和硅质岩的特征及构造意义     

廖宗廷  陈跃昆 《上海国土资源》1994,(3)

对广西丹池地区泥盆系浊积岩和硅质岩的沉积特征、岩石化学成分和形成机制的研究表明,它们是在受同生断裂控制的深水拗陷盆地中,由浊流和热水沉积而形成的沉积岩石。相同类型岩石的分布特征表现南盘江晚古生代沉积盆地呈浅海“台地”和深海“槽沟”相间排列的构造格局,其形成和演化与滇黔桂地体和云开地体的碰撞拼贴造山作用以及造山后地壳的蠕散拉伸作用有关。  相似文献   

Discovery of an outcropping Mass Transport Deposit (MTD) in the Palaeogene subalpine synclines of southeastern France: Implications on flexural sub-basin deformation     

《Comptes Rendus Geoscience》2014,346(1-2):37-44

We document the sedimentary facies of a large Mass Transport Deposit (MTD) within the sand-rich sediment gravity flow-dominated deposits of the Eocene–Oligocene south-western Alpine forelands (Annot Sandstone system). The MTD with an approximated volume of several hundreds of cubic kilometres fills a sub-basin located in the Mont-Tournairet confined sub-basin. Autochthonous facies are very typical sediment gravity-flow deposits (thin-bedded classical turbidites and thick-bedded hyperconcentrated to concentrated flow deposits) that stratigraphically belong to the Annot Sandstone infill. Slumps and internal metre-large fold axes of the deformed stratigraphic intervals indicate a main transport direction towards the northwest. The seafloor instability that led to the mass-flow events within the Mont-Tournairet sub-basin could have been favoured by high sedimentation rates in a small, confined and tectonically active sub-basin, possibly enhanced by local structural deformation associated with the Triassic evaporites on the eastern side of the Mont-Tournairet confined basin. The presence of the MTD suggests that a period of increased flexural subsidence rate and basin deformation occurred in this portion of the subalpine foreland basin. Therefore, the MTD forms a stratigraphic marker of a period of tectonic activity.  相似文献   

Turbidite Events Recorded in Deep-sea Core IR-GC1 off Western Sumatra: Evidence from Grain-size Distribution     

QIU Zhongyan  HAN Xiqiu  WANG Yejian 《《地质学报》英文版》2017,91(4):1448-1456

Sediment core IR-GC1, from the abyssal basin of the Indian Ocean off Sumatra, may provide important information on depositional events related to earthquakes and tsunamis. In this study, based on a combination of grain-size analysis with lithological studies and oxygen isotope stratigraphy, seven deep-sea turbidite layers were identified, corresponding to seven turbidity events that occurred at 128–130, 105–107, 98–100, 86–87, 50–53, 37–41 and 20–29 ka. The sediments of the turbidite deposits are characterized by coarse grain sizes, poor sorting, wide kurtosis, bimodal frequency distributions and clear depositional variations. Particle size grading is also an important signature of deep-sea turbidite deposits and can be used as an indicator to identify turbidite layers. Possible triggering mechanisms for the turbidite events include tsunamis, earthquakes, volcanic eruptions and sea-level changes.  相似文献   

Deepwater Turbidite Lobe Deposits: A Review of the Research Frontiers     

ZHANG Leifu  PAN Mao  WANG Hongliang 《《地质学报》英文版》2017,91(1):283-300

Deepwater/deep-marine turbidite lobes are the most distal part of a siliciclastic depositional system and hold the largest sediment accumulation on the seafloor. As many giant hydrocarbon provinces have been discovered within deepwater lobe deposits, they represent one of the most promising exploration targets for hydrocarbon industry. Deepwater exploration is characterized by high cost, high risk but insufficient data because of the deep/ultra–deepwater depth. A thorough understanding of the deepwater turbidite lobe architecture, hierarchy, stacking pattern and internal facies distribution is thus vital. Recently, detailed outcrop characterizations and high–resolution seismic studies have both revealed that the deepwater lobe deposits are characterized into four–fold hierarchical arrangements from "beds", to "lobe elements", to "lobes" and to "lobe complex". Quantitative compilations have shown that hierarchical components of lobe deposits have similar length to width ratios but different width to thickness ratios depending on different turbidite systems. At all hierarchical scales, sand–prone hierarchical lobe units are always separated by mud–prone bounding units except when the bounding units are eroded by their overlying lobe units thus giving rise to vertical amalgamation and connectivity. Amalgamations often occur at more proximal regions suggesting high flow energy. A mixed flow behavior may occur towards more distal regions, resulting in deposition of "hybrid event beds". These synthesized findings could(1) help understand the lobe reservoir distribution and compartmentalization therefore benefit the exploration and development of turbidite lobes within the deep marine basins(e.g. South China Sea) and(2) provide rules and quantitative constraints on reservoir modeling. In addition, the findings associated with deepwater turbidite lobes might be a good starting point to understand the sedimentology, architecture and hierarchy of turbidites in deep lacustrine environment.  相似文献   

湖平面变化对王58地区浊积扇形成与演化的控制作用研究     

王亚青 《西北地质》2009,42(1):51-56

在陆相断陷盆地内,湖平面变化、构造作用等外部因素对浊积扇体的形成与演化有明显的控制作用。以东营凹陷南斜坡王58地区沙四上浊积扇为例,分析了湖平面变化对浊积扇发育的控制作用。湖平面变化控制了沉积物供给,从而控制了扇体的发育期次。研究区纯上4砂组沉积时期,湖平面相对较低,研究区浊积扇体并不发育;浊积扇体发育在纯上2、3砂组沉积时期;纯上1砂组沉积时期,湖平面上升,研究区不再发育浊积扇。海平面变化控制了沉积物供给,控制了浊积扇体的发育类型。在纯上3砂组沉积时期,水体较浅,发育带水道的浊积扇;在纯上2砂组沉积时期,湖水较深,发育无水道的滑塌浊积扇。总之,随着湖平面的变化,王58地区沙四上浊积扇经历了从出现、发展直到消亡的整个过程,并且随着湖平面的变化,扇体由带水道的浊积扇体向元水道的滑塌浊积扇体转变。  相似文献   

东营凹陷东部沙三段滑塌浊积砂体沉积特征   总被引：10，自引：0，他引：10  

饶孟余  钟建华  王夕宾  王勇  王海侨 《煤田地质与勘探》2004,32(3):15-17

通过地质、测井、地震及室内综合分析,总结了东营凹陷东部沙河街组三段滑塌浊积砂体的沉积特征,认为滑塌浊积砂体的发育与古代三角洲的进积作用密切相关,可进一步划分为 5种沉积微相;同时建立了该区滑塌浊积砂体的垂向序列和演化模式,分析了滑塌浊积砂体的分布规律,丰富和发展了陆相湖泊浊流沉积的理论和内容。   相似文献