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891.
The experimental data in the microseismic frequency range obtained using the seismo-acoustic-hydrophysical measurement complex are analyzed. The emphasis is put on estimating the ratio between the energy of surface sea wind waves in the area of the Japan Sea where the complex was located and the Earth’s crust microdeformations in this frequency range. The experimental evaluate obtained allow us to estimate the energy re-distribution at the hydrosphere-lithosphere boundary.  相似文献   
892.
贵州南部一次突发性大暴雨的中尺度分析   总被引:9,自引:0,他引:9  
利用地面加密观测资料、贵州自动站雨量资料、FY-2C卫星红外辐射亮度温度(tbb)资料等,对2006年6月12日夜间贵州南部突发性大暴雨过程进行了中尺度分析.结果表明:具有类似于MCC(Mesoscale Convective Complex)特征的中尺度对流云团的发生发展及其缓慢东移是造成此次大暴雨的直接原因.对流层中低层大量的水汽输送和对流有效位能的积累为大暴雨的形成提供了有利的环境条件,中高层弱冷空气入侵使偏南暖湿气流被迫抬升、地面中尺度低压和辐合线的形成是暴雨发生的可能触发机制.中尺度天气系统具有低层辐合、高层辐散的高、低空配置,暴雨区南、北两侧的正、反垂直环流构成了中尺度次级环流圈的垂直结构特征.  相似文献   
893.
The energy distribution associated with a stringy charged black hole is studied using Møller’s energy-momentum complex. Our result is reasonable and it differs from that known in literature using Einstein’s energy-momentum complex.  相似文献   
894.
Petrogenesis and dating of the Kangding complex,Sichuan Province   总被引:18,自引:1,他引:17  
The Kangding group, also known as the Kangding complex, includes granulites, amphibolites, felsic gneisses and gneissic granites that are distributed along a belt from Kangding, Mianning to Panzhihua, in Sichuan Province. The complex has long been thought to represent the crystalline basement of the Yangtze block. On the basis of U-Pb and Pb-Pb whole rock ages[1,2] , and of similarities in metamorphic fa-cies and association of metamorphic rocks with typical Archean high grade terrains, t…  相似文献   
895.
The Higo terrane in west-central Kyushu Island, southwest Japan consists from north to south of the Manotani, Higo and Ryuhozan metamorphic complexes, which are intruded by the Higo plutonic complex (Miyanohara tonalite and Shiraishino granodiorite).The Higo and Manotani metamorphic complexes indicate an imbricate crustal section in which a sequence of metamorphic rocks with increasing metamorphic grade from high (northern part) to low (southern part) structural levels is exposed. The metamorphic rocks in these complexes can be divided into five metamorphic zones (zone A to zone E) from top to base (i.e., from north to south) on the basis of mineral parageneses of pelitic rocks. Greenschist-facies mineral assemblages in zone A (the Manotani metamorphic complex) give way to amphibolite-facies assemblages in zones B, C and D, which in turn are replaced by granulite-facies assemblages in zone E of the Higo metamorphic complex. The highest-grade part of the complex (zone E) indicates peak P–T conditions of ca. 720 MPa and ca. 870 °C. In addition highly aluminous Spr-bearing granulites and related high-temperature metamorphic rocks occur as blocks in peridotite intrusions and show UHT-metamorphic conditions of ca. 900 MPa and ca. 950 °C. The prograde and retrograde P–T evolution paths of the Higo and Manotani metamorphic complexes are estimated using reaction textures, mineral inclusion analyses and mineral chemistries, especially in zones A and D, which show a clockwise P–T path from Lws-including Pmp–Act field to Act–Chl–Epi field in zone A and St–Ky field to And field through Sil field in zone D.The Higo metamorphic complex has been traditionally considered to be the western-end of the Ryoke metamorphic belt in the Japanese Islands or part of the Kurosegawa–Paleo Ryoke terrane in south-west Japan. However, recent detailed studies including Permo–Triassic age (ca. 250 Ma) determinations from this complex indicate a close relationship with the high-grade metamorphic terranes in eastern-most Asia (e.g., north Dabie terrane) with similar metamorphic and igneous characteristics, protolith assembly, and metamorphic and igneous ages. The north Dabie high-grade terrane as a collisional metamorphic zone between the North China and the South China cratons could be extended to the N-NE along the transcurrent fault (Tan-Lu Fault) as the Sulu belt in Shandong Peninsula and the Imjingang belt in Korean Peninsula. The Higo and Manotani metamorphic complexes as well as the Hida–Oki terrane in Japan would also have belonged to this type of collisional terrane and then experienced a top-to-the-south displacement with forming a regional nappe structure before the intrusion of younger Shiraishino granodiorite (ca. 120 Ma).  相似文献   
896.
897.
A simple method for the determination of the position of singularities in the complex time domain for dynamical systems which are described by ordinary differential equations is presented. The method is designed for integrable separable systems whose solutions are not expressible in closed form. A direct consequence of this method is that it ‘closes’ the phase space. Simple physical meaning is given to the singularity position. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
898.
电提取中金的配阴离子运动分析及找矿机理   总被引:3,自引:2,他引:1  
从金离子在自然界的存在形式入手,分析了金的配阴离子在电场力作用下的运动形式,把金的配阴离子的运动分为4个区:配阴离子化学及电化学离解区;配服离子被电场力离解区;配阴离子被电场力离解了,但金离了无法作定向运动的非漂移区;配阴离子漂移或热运动区。提出了”本征提取域“概念,最后应用此概念讨论了4种情况下电提取离子法找金时异常形成的机理及其找矿优势。  相似文献   
899.
中国陆相复杂含油气系统的特征   总被引:2,自引:0,他引:2  
含油气系统研究是当今石油地质界最为热门的研究课题之一,在油气勘探中日愈发挥重要作用。在中国陆相多旋回族合叠加型盆地背景下的含油气系统多表现为复杂的多源多灶多期生烃和成藏。这种复杂的含油气系统有3个较突出的特点:(1)多源多灶致系统叠置和交叉;(2)多阶段多期生烃、成藏和变动导致多源混生;(3)多个关键时刻。在复杂含油气系统的演化过程中,常有多期大规模的油气运移过程,因上顷研究过程中要重视过程的恢复  相似文献   
900.
新疆西天山那拉提构造带变质核部杂岩分布于新疆巩留县那拉提山山脊北侧,整体沿那位提南缘构造带北侧呈近东西向展布,为一套由高级变质表壳岩、灰色片麻岩组成的早前寒武系高级片麻岩系,历经多期不同构造体制变形变质改造与再造,形成多相片麻岩系,并呈长垣状变质核部杂岩隆升,构成那拉提造山带的核部构造物质组成。  相似文献   
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