查询词典 subduction

Together with the petrographic observation, metamorphic dehydration is evident in Group I gneiss during the prograde subduction.

两组样品具有相似的稀土和微量元素配分模式，但是，组I样品的Nb与LREE显示很好的相关性，与LILE(Rb、Ba、Pb、Th和U)没有相关性，说明在脱水过程中LILE发生了不同程度的迁移活化。

The peak metamorphic minerals are garnet, omphacite,phengite and rutile with temperature of～500℃,pressure of～2.3Gpa.On the basis of geochemical analysis,the content of SiO2 in the eclogite ranges from 46.68%to 50.24%,Na2O+K2O 3.10～4.21%,and high REE with enriched LREE, LREE/HREE of 2.83～6.06.The REE pattern and trace element spidergram are similar with those of ocean island basalt,according with the blueschist from Longmucuo -Shuanghu suture zone.The protolith of the eclogite and blueschist are OIB,and they aremaybe the result of subduction of Permian OIB in central Qiangtang area.

对棉辉岩的地球化学分析显示，榴辉岩SiO_2含量在46.68—50.24%之间，Na_2O+K_2O含量在3.10—4.21%之间，稀土元素总量较高，轻稀土富集，重稀土相对亏损，LREE/HREE比值在2.83—6.06之间，稀土元素球粒陨石标准化曲线呈向右倾斜的样式，微量元素原始地幔标准化蛛网图OIB类似，这些特征和龙木错—双湖高压变质带的蓝片岩类似，它们的原岩为均为洋岛型玄武岩，形成环境类似于现在太平洋中的夏威夷，榴辉岩、蓝片岩很可能是羌塘中部地区出露的二叠纪洋岛型岩石俯冲消减的产物。

The metal elements of the volcanic-hosted massive sulfide deposit have two sources, the copper and zinc are derived from rhyolitic magmas whereas the lead are probably related to old sediments overlying the rhyolites.(4) It is suggested here that the volcanic rocks hosting massive sulfide deposit in the north Qilian orogen, which are previously considered as a bimodal suite of Neo-proterozoic to middle Cambrian age in a continental rift, are virtually related to subduction magmatism in Ordovician age, and there might have no continental rift magmatism of Neo-proterozoic to middle Cambrian in the north Qilian.

Th/Ta比高(5.0～11.7)，εNd为较大的负值(-2.6～-8.4)，流纹岩的形成可能是两个端元组分混合的过程、或是上地壳混染的结果，形成在活动陆缘环境；(3)北祁连块状硫化物矿床成矿金属物质具有两种来源，Cu、Zn等来源于流纹岩，而Pb的来源可能与古老沉积物有关；(4)本文认为，前人厘定的北祁连新元古代-中寒武纪赋存块状硫化物矿床的大陆裂谷双峰式火山岩应是与俯冲作用有关的奥陶纪火山岩，说明北祁连可能不存在新元古代-中寒武纪的大陆裂谷活动。

After interpreting natural earthquakes since 1953,the author also did a exploratory research on the lithospheric tectonic relationship of South Tienshan orogen,and considered in west and east side,West Kunlun orogen and Tafim block,and considered that Tarim block subducts beneath the West Kunlun orogen and South Tienshan orogen in two direction;In Pamir area,a syntaxis formed with the West Kunlun orogen obducts upon the South Tienshan orogen,and result in the two great orogens that rejuvenated during Cenozoic and the subduction and jointing relationship of the two orogens and Tarim block,showing a specific basin-and-range coupling system.

5通过对天然地震剖面的解释，探索了南天山造山带、西昆仑造山带和塔里木地块的岩石圈大地构造关系，认为在东西两侧，塔里木地块为南北直接俯冲于西昆仑造山带和南天山造山带之下的双向俯冲模式；在中部地区，西昆仑造山带在帕米尔地区形成构造结并仰冲于南天山造山带的前陆冲断带之上，形成了两个新生代复活的巨型造山带，以及两大造山带与塔里木地块之间的俯冲和对接关系，形成了独特的&盆一山&耦合体系

I-type granite occurs on north of HongliugouLapeiquan Fault, its chemical composition is similar to that of trondhjemite arisen by Barker (1979), maybe also a product of subduction and collision of oceanic basin in early Paleozoic.

根据SiO〓-Al〓O〓和SiO〓-FeO〓/图解判别显示造山后花岗岩的特征；后者分布在红柳沟—拉配泉断裂以北，其成分与巴克尔1979年提出的奥长花岗岩的成分非常相似，也可能是区内早古生代洋盆俯冲碰撞的产物。

Based on the regional tectonic evolution, combined with the high precision isotopic ages from this paper and other geologists, we have some new acquaintances as follows: 1 There has no Caledonian granite belt distributed in north margin of North China Craton. So, the traditional evolving model of North China Carton, which formed on this idea and the acquaintance about the collision of North China plate and Siberian plate, must be incorrect; 2 The age date show that the earliest magmatic activity began since late-Palaeozoic Permian, which is inconsistent with the previous idea that there were Caledonian and Hercynian active continental margin in the north of North China Craton and in the south Xingkai Massif. 3 the crust and lithosphere were thickened by the subduction and collision of Siberia plate and North China plate during Late Paleozoic. The magma is formed when the crust is heated and melts caused by thickened lithosphere delamination and caused the Asthenosphere upwelling. But only a little basaltic magma erupted, most magma underplate under the bottom of the crust. Thermal energy derived from basaltic magma underplating made the middle and lower crust melt partially and the late Permian-early Triassic granites is formed in large scale.

根据区域构造演化分析，并结合本文及他人高精度同位素年龄，我们对延边花岗岩形成的大地构造环境有了新的认识：1在华北地台北缘并不存在所谓的加里东花岗岩带，因此，建立在此之上的传统的华北地台北缘演化模式及有关西伯利亚板块与华北板块的碰撞拼合的认识也必然是不正确的；2华北地台北缘和兴凯地块南缘不存在加里东期和海西期花岗岩带，表明两地块边缘最早的花岗质岩浆活动始于晚古生代的二叠纪，即不存在传统观点所认为的加里东期或海西期活动陆缘；3晚古生代由于西伯利亚板块与华北板块的俯冲碰撞，致使地壳和岩石圈增厚，导致加厚岩石圈发生拆沉作用，使得软流圈上涌，加热地壳使之熔融形成岩浆，但玄武质岩浆少量喷出地表，大部分底侵于地壳底部，形成下地壳高密度的玄武质底侵层，玄武质岩浆底侵的热能引起中下地壳广泛部分熔融，形成大面积分布的晚二叠世—早三叠世花岗岩。

Sulu UHP eclogites are products of collision between South and North blocks. Subduction-exhumationof volumetrically continental materials gave rise to formation of diverse UHP metamorphic rocks, and simultaneously titanium mineralization with rutile as principle ore mineral.

苏鲁地区超高压榴辉岩是华南-华北板块碰撞的结果，巨量陆壳物质俯冲-折返形成了多样式的高压-超高压岩石，与此同时也发生了以金红石为主要矿石矿物的钛成矿作用。

Accompany with the subduction of Pacific and Indian plates, upper mantle convected more violently, and new upwelling astheosphere replaced and eroded the lithosphere, and resulted in irregular thinning of cloud-like mantle along reticulated or dondroid weak zones. The thinning was dominated by replacement of lithosphere with new upwelling astheosphere, and accompanied possibly by delamination.

在这过程中，特别是伴随太平洋、印度洋板块的俯冲作用，地幔对流加剧，上涌的新生软流体顶蚀置换岩石圈，从而造成了沿早期业已存在的幔内薄弱带网络，出现类以&蘑菇云状&的地幔不规则减薄，这种减薄以新生软流体取代岩石圈为主，并可能伴随一定程度的岩石圈拆沉作用发生。

The results are shown as below.1 Tectono-thermal evolution: The history of the Songliao basin is divides into four stages, high-temperature doming and extension, high-temperature rifting, low-temperature depression, and low-temperature shrinkage. Numerical simulation of mechanical process shows that the basin appeared in the early- to late- Jurassic as a result of rapid low-angle subduction of the Pacific plate towards the northwest, of movement of the Siberian block towards the southeast, of many other influences such as internal thermal stress in the mantle, gravitational force, stress of phase transition, etc. Both the Pacific plate and the Siberian block slowed down in the early Cretaceous, and almost stopped in the middle Cretaceous with the rapid decrease of abnormal heat in the mantle below.

盆地构造热演化力源机制数值模拟研究表明：早、中侏罗世至晚侏罗世晚期，盆地演化主要是太平洋块体向北西方向以低角度快速俯冲和西伯利亚块体向东南俯冲共同作用的结果，同时也与地幔内部热力、重力、相变力以及地球自转及公转速度变化效应和上覆块体绝对运动的作用有关；早白垩世早期至早白垩世中期，来自东部太平洋块体俯冲作用的减弱，而这一时期影响盆地演化的主要力源是地幔内部热力、重力、相变力以及地球自转及公转速度变化效应和来自西伯利亚块体俯冲作用；进入早白垩世晚期至晚白垩世早期，由于双重俯冲带中西侧俯冲作用带基本停止活动，而本区地幔热能的快速衰减则控制盆地的构造热演化；晚白垩世晚期以后，太平洋块体活动加强和地幔热运动是影响盆地演化的主要动力。

According to the isotopic dating,it was emplaced into the active continental margin in Permian,which was resulted from the eastward subduction of the Tethys sea.

结合同位素测年结果及其它地质事件，确定是在二叠纪侵位于活动陆缘，是区内古特提斯洋向东俯冲消减作用的产物。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。