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1.
龙门山造山带地质和地球物理资料的综合解释 总被引：16，自引：0，他引：16
宋鸿彪 《成都理工学院学报》1994,21(2):79-88
通过对航磁、重力、深部地壳测深、大地电磁测深及地热流值估算等多种地球物理资料和地质资料的综合研究，提出龙门山造山带地壳，上地幔结构模式，并通过平衡剖面恢复结合地史资料对龙门山造山带的演化进行了探讨。 相似文献
2.
“中央造山带”早古生代缝合带及构造分区概述 总被引：15，自引：2，他引：15
“中央造山带”是夹持于中国塔里木、华北和扬子克拉通之间的近东西向延展的（局部为北东向和北西向）显生宙造山系统。该造山带中包括了库地-喀拉塔什、红柳沟-肃北-北祁连、南阿尔金-滩间山、昆中、朱阳关-夏馆和商州-丹凤6条早古生代缝合带。被缝合带所围限的前寒武纪地质构造单元包括中阿尔金-祁连-金吉地块、柴达木地块、北秦岭地块和东、西昆仑2个变质地体。南秦岭原为扬子克拉通的北部边缘，但卷入了显生宙造山带，成为中央造山带的一部分。对上述6条早古生代缝合带和6个前寒武纪地质构造单元的特点进行了概略总结，并阐述了各地质构造单元中的构造地层系统和热-构造事件的年代格架。 相似文献
3.
中国—吉尔吉斯天山成矿单元划分及其特征 总被引：1，自引：0，他引：1
中国—吉尔吉斯天山地处中亚天山造山带中段,是古亚洲构造域的重要组成部分,地质构造复杂,矿产资源丰富。在收集境内、外大量地质、矿产资料及图件的基础上,通过近年来对研究区内地层、构造、岩浆及矿产的研究,在大地构造单元划分基础上对研究区内天山进行了成矿单元划分,划分出北天山—伊犁、中天山和南天山—塔里木3个成矿省,进一步划分为22个成矿带和58个成矿亚带,总结了各成矿单元的地质及矿产特征,为天山成矿带矿产勘查和地质大调查工作部署提供有益的思路和依据。 相似文献
4.
贡山地区两类特殊的区域动力热流变质作用 总被引：2，自引：0，他引：2
贡山地区存在两类特殊的区域动力热变质作用－低压热轴型、减压增温型。其共同特征是：具明显的递增变质现象，以地幔热流上升为主要因素，构造背景为碰撞造山。不同之处为：低压热轴型区域动力热流变质，形成于低压环境，变质岩石的分布与断裂、剪切带无明显关系；减压增温型区域动力热流变质，形成于中低压环境，变质岩石受韧性剪切带控制呈间隔带状出露。 相似文献
5.
华北东部裂陷盆地西与太行造山带、北与燕山造山带、东与胶辽山地、南与大别造山带均构成盆—山耦合，即中心裂陷盆地与外围各造山带均为耦合关系。研究表明：中心裂陷与华北地幔亚热柱的形成密切相关，由于地幔亚热柱强烈上隆，在岩石圈底部受阻。使华北东部岩石圈发生热减薄—断陷。同时，向外拆离的地幔岩在盆地外围形成一系列次级隆起（太行、燕山、胶辽、大别造山带），即地幔热柱多级演化的第三级单元—幔枝构造。各幔枝构造（造山带）间具有明显的可比性，并共同与中心裂陷盆地构成盆—山耦合关系。 相似文献
6.
地壳根、造山热与岩浆作用 总被引：8，自引：1，他引：7
简要讨论了近年来造山带及其岩浆作用研究的主要进展。造山带流变学结构与造山热和岩浆作用有着密切的耦合关系。年轻的山带往往存在地壳根,但古老的山带地壳根是否存在,取决于造山带的热状态和榴辉岩化的强度,只有缺乏流体和冷的造山带才保留有地壳根,例如古生代的南乌拉尔山和北美前寒武纪的南Trans-Hudson造山带。造山带的伸展塌陷往往伴随着幔源岩浆底侵、地壳软化、隆升和强烈岩浆作用。由于地幔浮力和造山热的作用,一些山带具有高的海拔和薄而热的地壳,属于具有长期活动性的构造带。研究表明,这些具有长期活动性的构造带,是建立在以前形成的热的、软化了的弧后区内。中国昆仑—秦岭—大别造山系北缘,古生代时期发育了与俯冲有关的弧岩浆带,而南缘发育了相近时代的与弧后伸展有关的双峰式岩浆带,构成古生代双岩浆带。该造山系早中生代的造山作用,就是在南缘的古生代弧后岩浆带基础上发展起来的。因此,该双岩浆带提供了造山热控制复合造山作用的实例。 相似文献
7.
Ｂａｒｒｏｗ（１８９３）提出了三个重要观点：（ｌ）关键性指示矿物的应用可确定变质带并推断区域变质作用的空间特征；（２）递增变质作用的概念；（３）热岩浆平流可能是区域变质作用的一个起因，这些都加深了对变质作用过程的理解。本文通过回顾我们对变质岩石ＰＴｔ轨迹得出的造山带动态演化的认识，以及考虑到造山带内不同类型区域变质作用的可能起因，来进一步探讨这些论题。通过峰值温度和压力的相对时间关系，对区域变质岩石可区分出两种不同的基本造山带类型。以顺时针ＰＴ轨迹为特征的造山带在达到峰值温度前获得峰值压力，变质峰期一般滞后于带内早期变形，高于“正常”传导热流的附加热与超覆量有关。相反，以逆时针ＰＴ轨迹为特征的造山带在获得峰值压力前达到峰值温度，变质峰期一般先于带内早期变形或与之同时，高于“正常”传导热流的附加热与深成任人体的就位有关。用于确定ＰＴｔ轨迹的手段有：变斑晶及反应结构中矿物包裹体序列的应用、温压计、流体包体的应用、诸如Ｇｉｂｂｓ方法的热力学方法、放射性同位素测年、裂变径迹研究和数字模拟。在合适的岩石中，我们可利用特定矿物共生组合来确定单条ＰＴｔ轨迹，并且同—造山带内的一套ＰＴｔ轨迹使我们能够解释变质作用动态演化过 相似文献
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9.
关于造山带花岗岩类填图方法的讨论——以西秦岭天水地区为例 总被引：3，自引：0，他引：3
花岗岩类的分类理论决定其填图方法。现行的单元－超单元填图方法是依据花岗岩类的Ⅰ型、S型分类理论和同源岩浆演化理论而建立的。由于同源岩浆演化理论的不完善性，造山带地壳结构及地质结构特征的复杂性、地质作用过程的多样性，导致了形成花岗岩类源岩组分的复杂性，使得Ⅰ型、S型分类在造山带具有不确定性，因而单元－超单元填图方法在造山带实践中存在较多问题和矛盾。造山带花岗岩类填图方法应以基本岩石分类方案为依据，以野外可识别、易掌握的客观岩石学、矿物学、组构学为准则，客观、真实地反映造山带花岗岩类的特色。 相似文献
10.
造山带中原始大地构造单元具有诸多相似的地质特征,要区分它们是很困难的.因此,本研究综述了保留完好的加利福尼亚海岸带的古弧前单元特征,旨在为其他造山带研究提供对比实例.加利福尼亚海岸带古弧前单元长约1000 km、宽100 km,包含上部板块物质和俯冲—增生过程中从下部板块铲刮下来而拼贴的俯冲杂岩.上部板块的构造单元包含... 相似文献
11.
Emily Keeble David I. Whiteside Michael J. Benton 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(2):99-119
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco. 相似文献
12.
Gilles Serge Odin 《Comptes Rendus Geoscience》2002,334(6):409-414
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414. 相似文献
13.
The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts 总被引：4，自引：0，他引：4
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species. 相似文献
14.
Emmanuel Skourtsos Daniel Vachard Alexandra Zambetakis-Lekkas Rossana Martini Louisette Zaninetti 《Comptes Rendus Geoscience》2002,334(12):925-931
Some olistolites reworked in a Tertiary flysch of Mount Parnon (Peloponnesus, Greece) exhibit a Late Permian assemblage, dominated by Paradunbarula (Shindella) shindensis, Hemigordiopsis cf. luquensis and Colaniella aff. minima. This association corresponds to the Late Wuchiapingian (=Late Dzhulfian), a substage whose algae and foraminifera are generally little known. Contemporaneous limestones crop out in the middle part of the Episkopi Formation in Hydra, but they are rather commonly reworked in Mesozoic and Cainozoic sequences. The palaeobiogeographical affinities shared by the foraminiferal markers of Greece, southeastern Pamir, and southern China, are very strong (up to the specific level), and are congruent with the Pangea B reconstructions. To cite this article: E. Skourtsos et al., C. R. Geoscience 334 (2002) 925–931. 相似文献
15.
正20141596 Liu Yunhuan(School of Earth Sciences and Resources,Chang’an University,Xi’an 710054,China);Shao Tiequan Early Cambrian Quadrapyrgites Fossils of Xixiang Boita in Southern Shaanxi Province(Journal of Earth Sciences and Environment,ISSN1672-6561,CN61-1423/P,35(3),2013,p.39-43,3 illus.,20 refs.) 相似文献
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正20141719 Chen Zhijun(State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China);Chen Jianguo Automated Batch Mapping Solution for Serial Maps:A Case Study of Exploration Geochemistry Maps(Journal of Geology,ISSN1674-3636,CN32-1796/P,37(3),2013,p.456-464,2 illus.,2 tables,10 refs.) 相似文献
17.
正20140962 Chen Fenning(Xi’an Institute of Geology and Mineral Resources,Xi’an710054,China);Chen Ruiming Late Miocene-Early Pleistocene Ostracoda Fauna of Gyirong Basin,Southern Tibet(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,87(6),2013,p.872-886,6illus.,56refs.) 相似文献
18.
正1.IGNEOUS PETROLOGY20142008Cai Jinhui(Wuhan Center,China Geological Survey,Wuhan 430205,China);Liu Wei Zircon U-Pb Geochronology and Mineralization Significance of Granodiorites from Fuzichong Pb-Zn Deposit,Guangxi,South China(Geology and Mineral Resources of South China,ISSN1007-3701,CN42-1417/P,29(4),2013,p.271-281,7illus., 相似文献
19.
正20141205Cheng Weiming(State Key Laboratory of Resources and Environmental Information System,Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China);Xia Yao Regional Hazard Assessment of Disaster Environment for Debris Flows:Taking Jundu Mountain,Beijing as an 相似文献
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正20141266Fan Chaoyan(Guangdong Provincial Key Laboratory of Mineral Resources and Geological Processes,Guangzhou 510275,China);Wang Zhenghai On Error Analysis and Correction Method of Measured Strata Section with Wire Projection Method(Journal of 相似文献