查询词典 Proterozoic

Dated from Proterozoic to Mesozoic, they have poly-circle characteristics, found from one tectonic circle to another, which is very rare in the worldwide orogens. This reveals that the orogen and stable area of the world, the mantle and crust states of the Proterozoic and Phanerozoic are different in tectonic evolvement and dynamic process and that the rapakivi granite of the Qinling-Kunlun is a kind of orogenic granite different from the stable area of the Proterozoic.

它们出现在每一个大的造山旋回晚期，即向另一个构造旋回的转折期，这在世界造山带中是十分罕见的，反映出世界上造山带与稳定区元古宙和显生宙的地慢与地壳状态是不一样的，有着不同的构造演化历史和动力学过程，表明秦岭－昆仑地区的环斑花岗岩是一种有别于元古宙稳定区的造山型环斑花岗岩。

Features and innovations in this study:(1) Longest successive time scale of Precambrian samples is studied;(2) The environmental and biological significances of the difference between . the carbon isotopic compositions of kerogen and coexisted carbonate were discoved;(3) The difference of biogeochemical processes between Proterozoic closed and open sea system was considered in the disccussion;(5) It is first time to carry out the chemolysis and thermolysis of kerogen in Precambrian organic matter research.(6) It is first time to apply molecular organic geochemical data to the reconstruction of Proterozoic Rodinia Supercontinent.

此项研究具有以下特色和创新之处：(1)研究对象连续时间跨度最长；(2)研究内容涉及面较全面；(3)较早详细探讨了前寒武纪沉积有机质的分子特征与古环境和生物群落的演化关系；(4)独立推导和论证了δ〓C〓和δ〓C〓的差值的生物和环境的重要意义；(5)在前寒武纪有机质研究中区分了局部封闭环境下的生物地球化学循环过程与广域海环境下的生物地球化学过程的差异；(6)开展了前寒武纪干酪根化学和热降解研究；(7)开创性地将分子有机地球化学的数据应用于元古宙Rodinia超大陆的重建中。

It mainly consists of SN trend Guan Yan geosyncline type rift moving for long time and EW trend Da-Hong-Shan original continental crust rift moving in the early proterozoic and Yuan Bian-E-Bian original continental crust rift moving in the Mid-Late Proterozoic.

首次提出元古宙该区的古大地构造性质为诞生于太古宙雏陆壳内及其斜坡的雏陆壳型三岔裂谷系，主要由元古宙长期活动的南北向昆阳地槽型裂谷和早元古宙活动的东西向大红山雏陆壳间裂谷与中晚元古宙活动的盐边—峨边雏陆壳间裂谷组成，并论证了它们的演化—运动史。

The basal continental crust of Tarim-Tianshan area in Xinjiang consists of the continental nucleus, which is composed of grey gneisses, greenstones, and potass granites similar to charnockites, and its accretionary belts mainly of the early Proterozoic and partly the Middle Proterozoic.

塔里木－天山地区基底陆壳由太古宙灰色片麻岩、绿岩和可能是紫苏花岗岩的含钾花岗岩类组成的陆核及其古元古代和少量中元古代增生带组成。

The consolidation started by the end of the Middle Proterozoic, followed by intraplate development stage of the Late Proterozoic.

它们在元古宙中、晚期拼合成哈萨克斯坦－塔里木联合古陆，并成为冈瓦纳超级大陆的一部分，中元代末固结。

The Early Proterozoic volcanic rocks of the Liaodong area are the important part of composition of Lower Proterozoic Liaohe Group. They are composed of two suites of the acid and basic volcanic rocks.

辽东地区早元古代火山岩是下元古界辽河群地层的重要组成部分，它们由酸性和基性两套火山岩组成。

Based on the settings and geological and geochemical characteristics of granitoids of different orogenic belts (exemplified by orogenic granitoids in Altay, East Kunlun, Yanshan in North China, Northeast China and Nanling in South China), the relationships between granitoids and continental crustal growth are discussed, and five modes of continental crustal growth in the continent of China are proposed;they are as follows:(1)the Altay mode of continental growth is that the material and heat of the Paleozoic convertive mantle formed on the background of the Paleo-Asian Ocean were input into the Paleozoic continent and mixed with the materials of the upper crust;(2) the East Kunlun mode is that the basement of the Proterozoic orogenic belt was reworked by the heat input and materials of the Paleozoic-early Mesozoic convective mantle formed on the background of TTG continental crust of the Proterozoic orogenic belt;(3) the Northeast China style is that the Phanerozoic continental crust was reworked by the heat input and materials from the convective mantle formed on the background of the Yanshanian Central Asian orogenic belt;(4) the Yanshan mode is that the Archean basement was reworked by the heat input and materials from the Yanshanian convective mantle;and (5) the Nanling mode is that in South China what was input by the Yanshanian convective mantle into the continent was mainly heat and subordinately materials and the crustal material recycle was the dominant mode for the continental growth (showing zero continental growth).

根据不同造山带花岗岩的形成背景，地质地球化学特征差异，以阿尔泰，东昆仑，华北燕山，东北和南岭造山带花岗岩为例讨论花岗岩与大陆地壳生长的关系，区分出中国大陆的5种大陆地壳生长方式：阿尔泰式是古亚洲洋背景上形成的古生代对流地幔物质，热输入和上地壳混合为主的方式；东昆仑式是元古代造山带TTG陆壳背景基础上古生代—早中生代对流地幔物质和热输入，改造元古宙造山带基底的方式；东北式是燕山期中亚造山带背景上对流地幔物质和热输入改造显生宙陆壳的生长方式；燕山式是燕山期对流地幔物质和热输入改造太古宙基底的方式；南岭式燕山期对流地幔输入大陆的是以热为主，物质为辅，大陆地壳生长是以陆壳物质再循环为主的生长方式。

Nalati tectonic belts as the ultimate demise suture of south Tianshan ocean between Tarim plate - Yili-plate, of which basement is composed of lower Proterozoic gneissic metamorphic supracrustal rocks of Nalati rock group and early Proterozoic gneissic granite.

塔里木-伊犁微板块间的南天山洋最终消亡缝合线——那拉提构造带，基底由下元古界那拉提岩群的片麻岩、变质表壳岩及早元古代片麻状花岗岩组成。

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。

And the results for two samples from Xiakangiayu, southeast of Xiaojue give an approximate age around 2.06～2.08 Ga for another episode of anatexis in the Paleo-Proterozoic time.

小觉西南下康家峪两块标本的测定结果，提供了该地区阜平群岩石在2.06～2.08 Ga经历了古元古代时期重熔作用改造的信息。

So it was last week in Selma , alabama.

上星期在亚拉巴马州塞尔马市发生的事件也是这样一个转折点。

The group also spearheads various social programs in China.

该组织还带头参与中国的各种社会活动。