断层输导作用与油气充注作用关系分析

断层是控制油气藏形成的重要因素之一;断层的开启及闭合影响到油气运移与聚集的效率。但油气在断层中的运移与在砂层中的充注存在差异性这一问题长期被忽视。一般认为;只要发育断层;其断开的渗透层就会被油气充注;极少关注地层水和石油的压缩特性对充注的影响。本文提出;地下单断层活动时;深部油气在超压作用下以涌流方式难以快速充注进入中浅层被切割的砂体;因此;单砂体至少要存在一条断层作为泄水出口;石油才能通过其余断层充注进入砂体;即单砂体要发育两条及两条以上断层;石油才能注入砂体。在断层静止期;油气通过渗流方式沿特定深度范围断面垂向运移;对油气垂向运移距离影响较小。本文运用4个大型盆地的典型油气藏与断层分布关系讨论了本文观点。该观点对油气成藏规律研究及成藏目标评价有较重要参考意义。     

西昆仑山前柯深—柯东地区断裂传递型超压的识别与计算

西昆仑山前柯深—柯东地区断裂构造活动剧烈,在浅部地层中存在压力系数高达2.1的极高超压,对于这种超压分布特征和形成机制的研究和认识对钻井工程和油气运移研究具有十分重要的意义。综合储层实测压力、间接估算的泥岩地层压力以及超压地层岩石力学与物性的关系等资料,并结合研究区断裂发育条件和油气运移史,分析了地层压力分布特征和主控机制。结果表明,西昆仑山前柯深和柯东两地区在古近系—白垩系储层中各自形成了相对统一的异常压力系统,系统内地层压力向深部以静水压力梯度增加,储层压力大于附近泥岩压力。研究区储层压力分布特征与深部流体沿开启性断裂的向上传递密切相关。在此基础上,估算了压力传递量,并探讨了影响压力传递量的地质因素。柯深和柯东地区断裂传递增压量分别为15.0～34.0 MPa和8.1～16.5 MPa,与实测总剩余压力的比值分别为24.2%～67.2%和23.4%～53.7%。两个地区断裂传递增压量的差异主要受断裂发育及其与地层的空间配置关系的影响。     

新疆东昆仑西段黄沙河地区托库孜达坂组地质特征及沉积环境分析

黄沙河地区位于新疆东昆仑西段南缘,属于昆南增生杂岩带,研究区内出露大面积下石炭统托库孜达坂组,为了厘定区内托库孜达坂组时代并对其沉积环境进行分析,本文在详细的野外地质调查基础上,通过地层层序学、岩石学及古生物学研究,将新疆东昆仑西段黄沙河地区托库孜达坂组分为下段碎屑岩段和上段碳酸盐岩段,将其时代厘定为早石炭世,结合区内碎屑岩粒度特征及放射虫化石特征,确定该套地层的沉积环境为半深海滨浅海环境。     

苏北—滨海断裂北段最新活动时代研究

苏北—滨海断裂在江苏以北的存在与活动性长期以来存在争议。本研究通过小多道地震探测技术,对苏北—滨海断裂北段及附近海域进行探测,识别出4个反射界面,将研究区第四纪地层划分为4个地震层序,分别对应全新世、晚更新世、中更新世和早更新世4个地质时期。对照区域地质构造,对地震剖面断点进行分析,认为断点F1、F2、F3、F4、F8、F9、F10对应为苏北—滨海断裂,断裂错动的最新地层为晚更新世,因此推断苏北—滨海断裂为晚更新世活动断裂。     

Late quaternary seismic stratigraphy and active faults of the Gulf of İzmit (NE Marmara Sea)

The Upper Quaternary seismic stratigraphy and active faults of the Gulf of İzmit were investigated by means of high-resolution shallow seismic profiling data in the source region of 1999 İzmit earthquake. High-resolution seismic reflection data correlated with borehole data indicate that the stratigraphy of İzmit Bay consists of three distinct depositional sequences formed in response to middle Pleistocene-Holocene sea-level changes. Reflector R, separating the pre-Holocene sequences (1 and 2) from the Holocene sequence (3), represents an erosional unconformity produced by the subaerial fluvial erosion of the continental shelves at the time of the last glacial maximum. Occasional, anomalous reflections (acoustic turbidity) observed within the Holocene sequence are interpreted as gas accumulations. The maximum thickness of the Holocene sediments is found to be about 25 m. The isopach map of Holocene sediment implies that the thickness of the Holocene decreases from the east towards the central and western basins of İzmit Bay. Two distinct fault systems are interpreted in İzmit Bay. The main fault system extending roughly in an E-W direction along the Gulf of İzmit is an active right lateral strike slip fault with a normal component. The secondary faults are normal faults striking in different directions and these are identified as being both active and inactive. In addition, prominent compressive features are identified in the seismic cross-sections of some profiles acquired to the east of Hersek Peninsula where the focal mechanisms of the aftershocks of the 1999 İzmit earthquake also reveal predominantly reverse faulting mechanisms, as identified by a local dense seismic network.     

昆仑山口大地震与地形变异常的讨论

针对昆仑山口大地震，总结了多种地形变（大地测量）手段所显示的异常变化及其时空分布，结果显示：8．1级大震前存在空间尺度大，时间尺度的地形变前兆异常，简要介绍了相关的异常图像，给出了初步解释，并对未来震情的发展进行了探讨，认为近期内强震活动向华北迁移的可能性不大。     

四川瀑布沟地区断裂破碎带的物质成分与断裂活动年代

本文主要研究断层泥中新生的粘土矿物特征,并研究断层泥中石英碎砾表面溶蚀的显微形貌结构特征。粘土矿物以X-射线衍射分析为主,石英碎砾则利用扫描电子显微镜对其显微形貌结构进行分析,并根据石英表面溶蚀的形貌特征来探讨断裂活动的相对年代     

纪念中国大陆科学钻探实施15周年、国际大陆科学钻探委员会成立20周年

大陆科学钻探是“入地”的重要手段,是“深入地球内部的望远镜”。中国大陆科学钻探事业开展15周年以来,取得重要进展,获得全球地学界的高度关注,特别是2001年实施的中国第一口大陆科学深钻 （5158m）,成果辉煌,影响巨大。继后,又开展了青海湖环境科学钻探、松辽盆地白垩纪科学钻探、柴达木盐湖环境资源科学钻探,汶川地震断裂带科学钻探以及中国大陆科钻资源集成计划,总共钻进约 35km,显示了中国科学钻探方兴未艾的景象。为纪念国际大陆科学钻探20周年（1996~2016）和中国大陆科学钻探实施15周年（2001~2016）,本文回顾中国大陆科学钻探实施15年来的艰辛和奋斗的历程,展望中国大陆科学钻探的未来。     

鄂拉山查查香卡地区晚三叠世火山岩产出环境分析

通过对查查香卡地区晚三叠世火山岩岩石学研究,确定该套火山岩属晚三叠世鄂拉山组,属钙碱性系列。喷出时的大地构造环境为陆内造山环境,该火山岩最初可能形成于大陆边缘环境,由于A型俯冲构造活动,测区乃至鄂拉山地区产生一系列右旋走滑断裂带,受北西向右旋走滑断裂的影响,岩石孔隙加大,并出现强烈的热流活动,导致岩浆沿这些断裂带喷出地表。     

Isotope Geochronologic and Geochemical Constraints on the Magmatic Associations of the Collisional Orogenic Zone in the West Kunlun Orogen,China

The Jiajiwaxi pluton in the southern portion of the West Kunlun Range can be divided into two collision–related intrusive rock series, i.e., a gabbro–quartz diorite–granodiorite series that formed at 224±2.0 Ma and a monzonitic granite–syenogranite series that formed at 222±2.0 Ma. The systematic analysis of zircon U-Pb geochronology and bulk geochemistry is used to discuss the magmatic origin(material source and thermal source), tectonic setting, genesis and geotectonic implications of these rocks. The results of this analysis indicate that the parent magma of the first series, representing a transition from I-type to S-type granites, formed from thermally triggered partial melting of deep crustal components in an early island–arc–type igneous complex, similar to an I-type granite, during the continental collision orogenic stage. The parent magma of the second series, corresponding to an S-type granite, formed from the partial melting of forearc accretionary wedge sediments in a subduction zone in the late Palaeozoic–Triassic. During continued collision, the second series magma was emplaced into the first series pluton along a central fault zone in the original island arc region, forming an immiscible puncture-type complex. The deep tectonothermal events associated with the continent–continent collision during the orogenic cycle are constrained by the compositions and origins of the two series. The new information provided by this paper will aid in future research into the dynamic mechanisms affecting magmatic evolution in the West Kunlun orogenic belt.