Seismicity and stress field in Okinawa Trough and Ryukyu regions     

黄培华  苏维加  陈金波 《地震学报(英文版)》1994,7(4):513-520

（黄培华）（苏维加）（陈金波）ＳｅｉｓｍｉｃｉｔｙａｎｄｓｔｒｅｓｓｆｉｅｌｄｉｎＯｋｉｎａｗａＴｒｏｕｇｈａｎｄＲｙｕｋｙｕｒｅｇｉｏｎｓ￥Ｐｅｉ－ＨｕａＨＵＡＮＧ；Ｗｅｉ－ｊｉａＳＵａｎｄＪｉｎ－ＢｏＣＨＥＮ（ＤｅｐａｒｔｍｅｎｔｏｆＥａｒｔｈａ...  相似文献   

Characteristics of Paleoseismic Activity Along the TianqiaogouHuangyangchuan Fault on the Eastern Section of the Qilian Mountains     

Zheng Wenjun 《中国地震研究》2005,19(2):139-151

1INTRODUCTION TheTianqiaogou Huangyangchuanfault(alsocalledGulangfault)isanimportantpartofanactivefaultzoneontheeasternsectionofthenorthernQilianMountains.Therecentactivityofthefaulthasbeenstudiedtodifferentdegrees(WanFuling,1987;InstituteofGeology,StateS…  相似文献   

Historical earthquake activity of the northern part of the Dead Sea Fault Zone, southern Turkey   总被引：1，自引：0，他引：1  

H. Serdar Akyuz  Erhan Altunel  Volkan Karabacak  C. Caglar Yalciner 《Tectonophysics》2006,426(3-4):281-293

The northern part of the Dead Sea Fault Zone is one of the major active neotectonic structures of Turkey. The main trace of the fault zone (called Hacıpaşa fault) is mapped in detail in Turkey on the basis of morphological and geological evidence such as offset creeks, fault surfaces, shutter ridges and linear escarpments. Three trenches were opened on the investigated part of the fault zone. Trench studies provided evidence for 3 historical earthquakes and comparing trench data with historical earthquake records showed that these earthquakes occurred in 859 AD, 1408 and 1872. Field evidence, palaeoseismological studies and historical earthquake records indicate that the Hacıpaşa fault takes the significant amount of slip in the northern part of the Dead Sea Fault Zone in Turkey. On the basis of palaeoseismological evidence, it is suggested that the recurrence interval for surface faulting event is 506 ± 42 years on the Hacıpaşa fault.  相似文献   

Early history of the Izu–Bonin – Mariana arc system: Evidence from Belau and the Palau Trench     

JAMES W.  HAWKINS & PATERNO R.  CASTILLO 《Island Arc》1998,7(3):559-578

Volcanic rocks of the Kyushu–Palau Ridge (KPR) from Deep Sea Drilling Project (DSDP) site 448 and from Belau comprise a low-to-medium-K arc tholeiitic series. Belau rocks include (probable) Mid-Eocene low-Ca type-3 boninite and pre-Early Oligocene–Early Miocene low-K arc tholeiitic basalt, basaltic andesite, andesite and dacite. Palau Trench samples include sparsely phyric high-Mg, -Cr and -Ni rocks which resemble the Belau boninite and Izu–Bonin – Mariana (IBM) system boninites. The high-Mg Palau Trench samples also resemble other primitive arc lavas (e.g. arc picrites). Their chemistry suggests an origin involving steep thermal gradients in multiply depleted mantle. Subduction of hot, young lithosphere under a young hot upper plate is postulated to explain this occurrence. The KPR is inferred to be the source of Eocene boninite and arc tholeiitic terranes presently in forearc regions of the IBM system. A model is presented here showing how many IBM boninites may have originated in a small area near Belau. These have migrated eastward by episodic back-arc opening accompanying eastward migration of arcs and trenches. Oldest known KPR rocks ( ca 47.5 Ma at DSDP site 296), and presumed KPR-derived exotic terranes of Guam ( ca 43.8 Ma), presage the postulated Eocene ( ca 42–43 Ma) change in Pacific plate motion invoked as the cause of subduction initiation at the KPR. The KPR has been rotated more than 40° clockwise since the Eocene, thus the age mismatch may indicate a different tectonic style, for example transtension or transpression, in earliest KPR history.  相似文献   

Outer slope faulting associated with the western Kuril and Japan trenches   总被引：5，自引：0，他引：5  

Kazuo Kobayashi  Masao Nakanishi  Kensaku Tamaki  & Yujiro Ogawa 《Geophysical Journal International》1998,134(2):356-372

  相似文献   

陕西勉略宁三角区基本地质组成及演化   总被引：5，自引：0，他引：5  

王根宝  崔继岗 《西北地质科学》1996,17(2):11-17

陕西勉略宁三角区发育４大套不同构造背景下所形成的岩石组合，表明区内经历了晚太古结晶基底与早中元古浅变质火山岩过渡基底形成、晚元古一早古生代扬子大陆边缘演化、勉略海槽演化及陆内造山４个大的复杂演化阶段，最终形成今日之基本构造格局与地质面貌．  相似文献   

What controls the lateral variation of large earthquake occurrence along the Japan Trench?   总被引：1，自引：0，他引：1  

Yuichiro  Tanioka  Larry  Ruff Kenji  Satake 《Island Arc》1997,6(3):261-266

Abstract The lateral (along trench axis) variation in the mode of large earthquake occurrence near the northern Japan Trench is explained by the variation in surface roughness of the subducting plate. The surface roughness of the ocean bottom near the trench is well correlated with the large-earthquake occurrence. The region where the ocean bottom is smooth is correlated with'typical'large underthrust earthquakes (e.g. the 1968 Tokachioki event) in the deeper part of the seismogenic plate interface, and there are no earthquakes in the shallow part (aseismic zone). The region where the ocean bottom is rough (well-developed horst and graben structure) is correlated with large normal faulting earthquakes (e.g. the 1933 Sanriku event) in the outer-rise region, and large tsunami earthquakes (e.g. the 1896 Sanriku event) in the shallow region of the plate interface zone. In the smooth surface region, the coherent metamorphosed sediments form a homogeneous, large and strong contact zone between the plates. The rupture of this large strong contact causes great under-thrust earthquakes. In the rough surface region, large outer-rise earthquakes enhance the well-developed horst and grabens. As these structure are subducted with sediments in the graben part, the horsts create enough contact with the overriding block to cause an earthquake in the shallow part of the interface zone, and this earthquake is likely to be a tsunami earthquake. When the horst and graben structure is further subducted, many small strong contacts between the plates are formed, and they can cause only small underthrust earthquakes.  相似文献   

The transition from an active to a passive margin (SW end of the South Shetland Trench, Antarctic Peninsula)     

Antonio Jabaloy  Jun-Carlos Balany  Antonio Barnolas  Jesús Galindo-Zaldívar  F. Javier Hernndez-Molina  Andrs Maldonado  Jos-Miguel Martínez-Martínez  Jos Rodríguez-Fernndez  Carlos Sanz de Galdeano  Luis Somoza  Emma Suriach  Jun Toms Vzquez 《Tectonophysics》2003,366(1-2):55-81

The lateral ending of the South Shetland Trench is analysed on the basis of swath bathymetry and multichannel seismic profiles in order to establish the tectonic and stratigraphic features of the transition from an northeastward active to a southwestward passive margin style. This trench is associated with a lithospheric-scale thrust accommodating the internal deformation in the Antarctic Plate and its lateral end represents the tip-line of this thrust. The evolutionary model deduced from the structures and the stratigraphic record includes a first stage with a compressional deformation, predating the end of the subduction in the southwestern part of the study area that produced reverse faults in the oceanic crust during the Tortonian. The second stage occurred during the Messinian and includes distributed compressional deformation around the tip-line of the basal detachment, originating a high at the base of the slope and the collapse of the now inactive accretionary prism of the passive margin. The initial subduction of the high at the base of the slope induced the deformation of the accretionary prism and the formation of another high in the shelf—the Shelf Transition High. The third stage, from the Early Pliocene to the present-day, includes the active compressional deformation of the shelf and the base-of-slope around the tip-line of the basal detachment, while extensional deformations are active in the outer swell of the trench.  相似文献   

马里亚纳海沟浮游病毒垂直分布及动态变化     

李中石  汪岷  罗志祥  刘璐  夏骏  宫政  姜勇  邵红兵  陈洪涛  田纪伟 《海洋与湖沼》2018,49(6):1251-1258

为探究马里亚纳海沟浮游病毒生态特征的垂直变化规律,本研究于2015年12月采集马里纳亚海沟表层到8727m共六层水样,对浮游病毒丰度,浮游细菌丰度,微微型浮游植物丰度以及裂解性浮游病毒生产力进行了分析。流式细胞技术分析结果表明,马里亚纳海沟各层浮游病毒丰度范围为1.27×105—1.93×106VLP/mL,其中表层丰度最高,随后逐渐降低,最低值出现在3699m处。而在深渊海沟区域内病毒丰度略有上升,最深处8727m病毒丰度为2.85×105VLP/mL。马里亚纳海沟裂解性浮游病毒生产力变化范围为2.86×104—4.21×105VLP/(mL·h),其垂直分布呈现出与浮游病毒丰度相似的趋势,生产力最高值出现在表层,随后在相对较低的水平变动,而在深渊海沟区域内随深度略微上升, 8727m处生产力为4.08×104VLP/(mL·h)。同时本文根据假定的研究区域浮游病毒平均裂解量及宿主平均有机物质含量计算出病毒导致的细菌死亡率(VMM)以及相应的有机碳和有机氮释放量,其中VMM变化范围为1.59×103—2.34×104cells/(mL·h),8727m处VMM为2.27×103cells/(mL·h)。而每小时病毒导致的细菌死亡数在总细菌数量中占比在8727m处最低,为4.6%,这表明浮游病毒在深海环境中的侵染活性相对较低,可能由于极端环境下浮游病毒多以溶源状态存在。在深渊海沟内部观察到相对较高的浮游病毒丰度以及相对较低的病毒生产力水平,表明该水域浮游病毒死亡率较低,这或许与海沟内温度极低且环境相对隔离有关。各层浮游病毒丰度及生产力与环境因子间相关性分析结果表明,浮游病毒丰度和生产力均与浮游细菌丰度表现出较高的正相关关系(P0.05),同时病毒生产力也表现出与温度的显著正相关性,表明浮游病毒的活跃程度主要依赖于宿主细胞的浓度以及海水温度。  相似文献   

鳞侧石鳖属(Leptochiton)一物种在西太平洋雅普海沟分布的新记录     

王春生  周亚东  姜丹  韩洁 《海洋学报(英文版)》2018,37(10):205-208

蛟龙号载人潜水器在位于雅普海沟北部6 745 m深处的底栖沉积环境中采集到两只石鳖样本,这是石鳖物种分布于此的新记录。形态学和DNA分子标记均支持两只石鳖为鳞侧石鳖属（Leptochiton）同一物种。该种在形态上与L.vanbellei和L.deforgesi接近;在系统发生方面,与L.vanbellei,L.deforgesi和L.boucheti的亲缘关系密切。这是截至目前世界石鳖分布报道的第三深度记录。  相似文献