查询词典 subducted
- 与 subducted 相关的网络例句 [注:此内容来源于网络,仅供参考]
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On basis of analysis of typical cases, four kinds of foreland basins were recognized:(1) subducted-collisional foreland basin;(2) retro-arc foreland basin (arc-continental collisional foreland basin);(3) intracontinental subducted foreland basin; and (4) strike-slip foreland basin.
在典型实例分析基础上,划分出四种类型的前陆盆地:(1)俯冲碰撞型前陆盆地;(2)弧后前陆盆地;(3)陆内俯冲型前陆盆地;(4)走滑型前陆盆地。
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According to the variation in the components of intermediateacid igneous rocks coming from the lower crust, it is possible to restrain the depth of the source area and the minimum thickness of the crust, and thus to provide important information for the study of the deep process of the continental intraplate mineralizationGlobally, many world level porphyry copper deposits and metallogenic systems formed by hypabyssal hot liquid have their close relationship with the synchronous adakite in spacetime and genesis; domestically, the adakitelike rocks have been identified to be related to the metallogenesis in the main metallogenic areas in ChinaThe recognition of adakitelike rocks having no relationship with the process of subduction makes it possible to construct a metallogenic model of continental intraplate porphyry metal deposits by combining other geological evidences, and this model is totally different from the metallogenic model of porphyry copper deposits with Bsubduction setting constructed by Sillitoe (1972)The existence of adakitelike rocks may be the necessary condition but not the sufficient one for forming the largescale porphyry deposits and the hypabyssal hotliquid deposits, whose metallogenic elements mainly came from the mantleThe metallogenic potential of adakitelike rocks is achieved by the entering of the mantle material, and the metallogenic specialization of adakitelike rocks is decided by the distribution characteristics of the metallogenic elements in the upper mantleAn important reason for the adakitelike magma related to subduction being advantageous to mineralization is that there were abundant high pressure and high temperature liquid coming from the subducted platepieces and the magma of high fO2 coming from the melting of subducted platepiecesHowever, for those adakitelike rocks, whose occurrence has continental plate background but does not relate to the subduction, their metallogenic mechanism is not clear yetBased on the concept of modern mineral exploration and combined with the analysis of integrated geological information, we may better realize the practical prospecting significance of the adakitelike rocks
根据起源于下地壳的中酸性岩浆岩的成分变化,可以约束其源区深度以及地壳最小厚度,为大陆板内成矿作用的深部过程研究提供重要信息。全球范围内,许多世界级斑岩铜矿和浅成热液矿化系统与同期的埃达克质岩存在密切的时空与成因联系,在国内主要成矿区带也识别出与金属成矿作用有关的埃达克岩。与俯冲过程无关的埃达克质岩的识别,使我们有可能结合其他地质证据构建完全不同于Sillitoe(1972)B型俯冲环境的斑岩铜矿成矿模式的大陆板内斑岩型金属矿床成矿模式。对于规模巨大、矿质主要源自地幔的热液矿床的形成,埃达克岩可能是必要条件,但不是充分条件。埃达克岩的成矿潜力通过地幔物质加入而获取,埃达克岩的成矿专属性由上地幔成矿元素分布特征决定。与俯冲有关的埃达克质岩浆之所以有利于成矿,重要的原因是存在大量来自俯冲板片的高压、高温流体以及俯冲板片熔融形成高氧逸度(fO2)的熔体,但产出在大陆板内背景、与俯冲无关的埃达克岩的成矿机制还不清楚。根据现代资源勘查理念,结合综合地质信息分析,埃达克质岩具有实际找矿意义。
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They are:①completed total 8 000 km long natural seismic profiles cross the northern boundary and central part of the plateau, identified several deep-cut lithospheric faults and low velocity and low density bodies under the central part of the plateau related to Cenozoic volcanic eruption, the Tarim block subducted beneath the Altun Mts;②found the evidence that the Altyn Tagh fault formed in 220~240 Ma and at least 400 km sinistral offset since, and determined quantitatively deformation in Cenozoic;③discovered 350 km long high-ultrahigh pressure metamorphic belt in the south border of the Qilian terrane,which brobably represented the Early Paleozoic boundary between the North China and Yangtze plates;④according to new discoveries of caledonian ophiolite,granite are subducted complex established paleo-collision orogenic framework of northern Qinghai-Tibet plateau;⑤proposed a new model .
本文展示了中法1995~2000年青藏高原北部地学研究的如下主要新进展:①完成8 000 km长的青藏高原北部及中部天然地震岩石圈探测剖面,确定若干条岩石圈断裂,发现与新生代火山喷发有关的青藏高原中部深处的低速、低密度体,塔里木地块俯冲于阿尔金山之下;②提出阿尔金断裂形成于220~240 Ma和左行平移400 km的科学依据及确定其新生代变形量;③确定祁连南缘350 km长的高压-超高压变质带,提出其可能代表早古生代时期北中国板块与扬子板块之间西部界限的新认识;④根据加里东期蛇绿岩、花岗岩及俯冲杂岩带的新发现,初步建立了古碰撞造山格架;⑤提出高原隆升的&地幔底辟和内向陆内俯冲&的新假设。
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However, the Nb/Ta ratios lower than chondrite value (~17) in eclogites are inconsistent with previously proposed Nb/Ta high in subducted oceanic crust to complement the mass balance of Nb and Ta in the evolution of continental crust.
柴北缘沙柳河、鱼卡河、锡铁山和胜利口的榴辉岩类样品的地球化学分析显示它们的原岩的主体是与洋壳有关的火山岩,其中包括岛弧拉斑玄武岩、洋岛火。。。
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The lack of consistent high Poisson′s ratio (≥0.30) shows that widespread partial melt does not exist within the curst, but does not exclude the presence of local partial melt.③There is an obvious thickened zone of the mantle transition zone compared with IASP91 standard value which varies from 10 km to 26 km in Qiangtang terrane. The anomaly suggests that the temperature is about 100 ℃ to 260℃ lower than global average value within the mantle transition zone, and it may be attributed to the presence of a subducted slab within the mantle transition zone.
缺乏高的泊松比(≥0.30)分布表明青藏高原东南缘的地壳不存在广泛的部分熔融,但是不排除局部部分熔融的存在;③青藏高原东南缘的羌塘地体内存在一个比较明显的、异常变化范围为10~26 km的地幔过渡带增厚区域,其对应着地幔过渡带内100℃~260℃的温度降低,可以推断与此异常区域的地幔过渡带内存在俯冲的板块有关。
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The different metamorphic evolutional paths of the two sub-belts signify the differential exhumation histories of the subducted continental crust.
都兰两个变质带不同的变质演化轨迹反映了俯冲的大陆地壳具有差异折返的特征。
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This type of faulting is common in areas of compression, such as regions where one plate is being subducted under another as in Japan.
这种类型的断层通常出现在挤压区域,比如像日本那样的,板块向另一板块之下俯冲的区域。
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1:250000 geological mapping has further revealed the mysteries of the tectonics of the Qinghai-Tibet Plateau. The Altun Mountains are not of the Tarim massif, but a part of the Kunlun-Qilian-Qinling orogenic system; the Altun fault is a large transform fault; the Muztag-Maqên suture zone and Jinshajiang suture zone are both Variscan ones; the Songpan-Garzê area in the Triassic was a huge turbidite basin on the southern margin of Laurasia; the Gangdise belt underwent the important Indosinian orogenic movement; an ocean basin that persisted from the Paleozoic to Triassic did not exist, i.e. the so-called Paleo-Tethys or permanent Tethys was not in existence in the Qinghai-Tibet Plateau. In the Paleozoic, most parts of China, including the Sino-Korean, Yangtze and Tarim massifs and the Qinghai-Tibet Plateau, were located in south of the main ocean basin—the Central Asian-Mongolian sea way—of the Paleo-Asia ocean, belonging to the northern margin of Gondwana. The Yarlung Zangbo and Bangong -Nujiang belts were twins in the Tethyan Ocean, which began to develop into two ocean rift belts in the Triassic. The Tethyan Ocean with the Yarlung Zangbo belt as the main ocean basin belt began to be subducted in the Late Triassic and experienced a process of pulsatory plate convergence orogeny including the Indosinian, Yanshanian and Himalayan stages.
1:25万地质填图进一步揭开了青藏高原地区大地构造的奥秘:阿尔金山是昆仑,祁连-秦岭造山系的一部分;阿尔金断裂确是一条大型转换断层;木孜塔格-玛沁缝合带和金沙江缝合带均是华力西缝合带;松潘甘孜三叠系沉积盆地是劳亚大陆南部边缘的浊积岩盆地;冈底斯带曾经历了重要的印支造山运动;不存在从古生代延续到三叠纪的大洋盆地,即不存在所谓古特提斯或永久特提斯;古生代时期,在青藏高原地区亦不存在具古生物,古地理分隔意义的大洋盆地,当时,包括中朝,扬子,塔里木以及青藏高原地区在内的中国大部分均位于古亚洲洋主洋盆——中亚-蒙古带之南,属冈瓦纳大陆结构复杂的北部边缘;雅鲁藏布江和班公湖-怒江带是特提斯洋中的孪生姊妹,它们均是从三叠纪起就发展成大洋裂谷带的;以雅鲁藏布江带为主洋盆带的特提斯洋,从三叠纪晚期开始消减,经历了印支,燕山,喜马拉雅3个阶段脉动式板块汇聚造山过程。
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The early stage of me tamorphism happened before deformation in the upper mantle at about 60-70km. Then metagabbro emplaced rapidly at about 40 km by diapirism and perhaps amalgamated with cool subducted oceanic crust. After that, rapid cooling retrograde metam orphism occurred. Early rapid ocean spreading was constrained because subduction appeared. Therefore, metagabbro continued to uplift under the slow extension. At last, it obducted and thrusted to outcrop on the surface.
变形前的早期变质可能发生在60~70km处的上地幔,然后变质辉长岩快速"底辟"构造侵位,上升至约40km深处,可能与俯冲的冷洋壳并置,发生快速降温退变反应;因俯冲作用的开始,抑制了洋盆快速扩张,变质辉长岩在减速伸展环境下继续抬升减压;后期又由于仰冲推覆,最终出露地表。
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The evolution process under the control of the multigeodynamic force system (including the boundary forces of Eurasia-Pacific-Indian three massive plates around Nansha block, effects of the deep mantle, relative soft layer-sliding planes within Nansha lithosphere block and the earth's rotational inertial force) can be briefly divided four stages: the late Cretaceous to the early Eocene stage of uprilfing-erosion and shear-extension caused by the oceanwards-eastwards withdrew of Pacific subduction zone and the delamination of proto-subducted slab after the stage of pre-Cretaceous pre-rifting active continentoceanic plate margin. In this stage, the Nansha transcrustal layering-block started to move southeastwards on the Nansha transcrustal layer-sliding plane, meanwhile, the Andu-Bisheng and Liyue-Banyue basement layering-block slid on their upper-crust layer-sliding planes, and Xibu accretion zone was formed. Successively, it entered the stage of the mid-Eocene to early Oligocene, when NW-SE sea-floor spreading occurred in the southwest subbasin owing to the slip-line field initiated by the collision between the Indian and Eurasian plates, Zengmu foreland-basin started to develop in the same time. And in the stage of late Oligocene to early Miocene, near NS simple-shear extension and sea-floor spreading in the central subbasin of eastern South China Sea resulted from the south-southeastwards drawing-force of the mantle-flow. The crustal layering-blocks and the Miri accretion zone formed also in this stage.
南沙岩石圈新生代微板块及板内层块构造的动力演化过程,在多元动力等因素(如块体之外的欧-太-印三大板块运动边界力和地幔深部活动因素、块体内部软弱层滑面以及地球自转变化)控制下,大致经历了4个阶段的演化:从前晚白垩世的裂前活动陆-洋板块边缘阶段因太平洋俯冲带向东跃迁、原向NNW俯冲消亡的板片的拆沉、幔隆而进入晚白垩世-早始新世的隆升剥蚀、剪切伸展演化阶段,南沙超壳层块顺超壳层滑面祥东南运移、安渡-毕生与礼乐-半月基底层块沿上壳层滑面拆离,西布增生带形成;继而先后在中始新世-早渐新世期间受印-欧板块碰撞滑线场、地球自转加速影响出现西南海盆NW-SE向海底扩张和曾母前陆盆地的发育,和晚渐新世-早中新世期间南—东南向地幔流牵引造成的中央次海盆近NS向单剪伸展与海底扩张、壳体层块向南差异滑移、米里增生带形成;中中新世以来,印度-澳洲板块快速向北俯冲,构成今日南海格局。
- 推荐网络例句
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That's what makes this mod unique.
这也正是这个MOD独特。
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I now feel furious and want to do something.
现在我觉得非常气愤,想做点什么。
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The integrated control of the active suspension system and electric power steering system is studied.
研究了主动悬架和电动助力转向的集成控制问题。