洋盆

Oceanic subduction-type eclogite in the Lhasa block, Tibet, China: Remains of the Paleo-Tethys ocean basin?

青藏高原拉萨地块中的大洋俯冲型榴辉岩：古特提斯洋盆的残留？

Characteristics of these two kinds of spinels not only indicate that the whole terrain underwent granulite facies metamorphism but also provide direct mineralogical evidence for the argument that Yushugou ophiolite suite of granulite facies lies in an environment of oceanic basin.

这两类尖晶石的特征一方面说明该地体遭受了麻粒岩相的变质作用改造，另一方面也提供了榆树沟麻粒岩相蛇绿岩套属洋盆构造环境的直接矿物学证据。

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。

In addition, the met amorphic PTt path reflects that the thickness of oceanic crust of the Mian-Lue small ocean is thinner than that of the standard oceanic crust.

此外，变质作用PTt轨迹还反映勉略小洋盆洋壳厚度与标准大洋型洋壳厚度差异较大。

During end_Proterozoic and early Early Paleozoic, the northern row extended into archipelagic oceans, which closed by the end of Caledonian stage and formed foreland basins along the northern margin of the microplates.

元古代末至早古生代早期，北列拉张成多岛小洋盆，它们在加里东末期关闭，并在微板块群北缘形成前陆盆地带。

The epicontinental volcanic magma arcs and residual sea basins that occurred at the stages of the oceanic crust subduction and oceanic basin closure, and the epicontinental volcanic...

在洋壳俯冲和洋盆闭合阶段陆缘火山岩浆弧、残余海盆和俯冲带上形成的陆缘-火山碎屑沉积相、含碳质沉积相及混杂蛇绿岩块等是金丰度较高的地质体，构成了成矿系统潜在的矿源层。

The volcano-sedi mentary strata,with principal part calcareous turbidites and outcroping at Juema -Bage and Zhaxi,are products of an active continental margin:the island arc tho leiite recording a subduction of the major oceanic basin of Paleotethys in early Late Triassic.

上述发现为碧土带是复杂的造山带拼贴体、古特提斯主洋盆是开阔的多岛洋和晚三叠世活动大陆边缘可能属马里亚纳型提供了重要证据。

Kalamaili suture zone is an important plate boundary in north Xinjiang, and there are plenty of Neopaleozoic volcanic rocks around itThese volcanic rocks are enriched in LILEs and relatively depleted in HFSEs, and they are also characterized by high Nb, Zr, TiO2 contents and Zr/Y, Nb/Y ratios, and depleted SrNd isotopesThe characteristics of these volcanic rocks suggest that they were produced in postcollisional periodThe postcollisional volcanic rocks around Kalamaili suture zone become younger from west to east, which indicates that this suture zone entered postcollisional period gradually from west to east, and reflects that the Kalamaili Ocean had been closed gradually from west to eastAs to the Kalamaili suture zone in postcollisional period, the lithosphere extended and thinned, and the asthenosphere materials upwelled and melted partially, and intensive mantle convection occurred, leading to a plenty of mantlederived magmas underplating the suture zoneThe lithospheric mantle metasomatized by fluid in subduction period melted partially under decompression and high temperature, the resulting melts contaminated the underplating asthenospheric materials, and the erupted lavas became the Neopaleozoic postcollisional volcanic rocks

卡拉麦里缝合带是北疆的一条重要界线，沿该带广泛发育晚古生代火山岩。这些火山岩具有LILE相对富集、HFSE相对亏损的特征，且具有较高的Nb、Zr、TiO2含量和Zr/Y、Nb/Y比值，SrNd同位素主要表现出亏损的特征。综合分析表明，这些火山岩形成于后碰撞期。对卡拉麦里缝合带而言，从西向东后碰撞火山岩的时代逐渐变新，表明该缝合带从西向东逐渐演化进入后碰撞期，这从侧面反映了卡拉麦里洋盆是从西向东逐渐关闭的。对卡拉麦里缝合带而言，在后碰撞期，岩石圈伸展减薄，软流圈地幔物质上涌并发生部分熔融，加上地幔对流作用强烈，使得缝合带下产生了大规模的幔源岩浆底垫；先前在洋壳消减期被流体交代提取过的岩石圈地幔也在低压高温下发生部分熔融，形成的熔体混染了底垫的软流圈物质并喷发，形成了晚古生代的后碰撞期火山岩。

In accordance with the characteristics of the occurence and tectonic emplacement of the ophiolitic belt.

目前认为蛇绿混杂岩带是洋盆闭合时洋壳残片构造侵位到陆壳之中的产物，为无序层序，相当于造山带非史密斯地层学划分类型的构造混杂体类，即由构造包体和基质两大部分组成。

Tectonic analysis of Pre-Carboniferous metamorphic stratum and structural foliation dating have shown that The Qinling and its vicinities had happened an important regional tectonic event -Caledonian event, this event represents early paleozoic closure of the Qinling ocean basin and continent-continent obliquely diachronous collision, so we also could reconstruct Caledonian Qinling orogenic belt's basic tectonic framework.

对北秦岭地区前石炭纪变沉积—火山岩地层系统进行构造解析，以及构造面理定年数据表明，秦岭及邻区志留纪至早泥盆世经历了区域性的重大构造事件，相当于加里东事件，该事件代表了秦岭早古生代洋盆闭合、陆—陆碰撞造山的造山事件，并可恢复加里东古造山带的基本构造格局。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。