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1.
东昆仑造山带结构及构造岩片组合   总被引:17,自引:7,他引:17       下载免费PDF全文
王国灿  张克信 《地球科学》1997,22(4):352-356
东昆仑造山带可划分为5个构造单元,自北而南分别为东昆北单元,东昆中混杂岩带,东昆南单元,阿尼玛卿混杂岩带和巴颜喀拉单元,东昆中混杂岩带,东昆南单元和阿尼玛卿混杂岩带是由不同层次,不同产状,不同性质,成生于不同时期的断裂所分割的多级次构造央片组合而在的复杂构造带,从填图尺度可划分为超岩片,岩片两级,结合1:25万加鲁河幅地质填图,对东昆仑地区岩片组合特点及东昆仑造山带结构构造有关问题作了阐述。  相似文献   

2.
将东昆仑造山带划分为东昆北古老基底单元、东昆中早古生代构造混杂岩带、东昆南早古生代构造混杂岩带、马尔争-布青山晚古生代构造混杂岩带和巴颜喀拉山三叠纪浊积盆地5个次级构造单元,重新厘定了东昆仑不同构造混杂岩带的组成、结构、性质和时代,恢复了古海盆的演化历史.通过成分分析和颗粒裂变径迹年龄分析,确定了测区巴颜喀拉山群物源来自北部,基底性质可与马尔争-布青山带相对比,恢复了巴颜喀拉山群经历的构造热历史.运用构造年代学分析方法限定了测区经历的几次重大地质历史转折事件.确定了测区浆混花岗岩的存在.通过构造地貌和第四纪沉积分析,揭示了测区第四纪成山作用过程、水系变迁过程和古环境古气候演变过程.新发现一中型砂岩型铜矿.  相似文献   

3.
阿拉克湖幅地质调查新成果及主要进展   总被引:4,自引:5,他引:4  
将东昆仑造山带划分为东昆北占老基底单元、东昆中早占生代构造混杂岩带、东昆南早古生代构造混杂岩带、马尔争一布青山晚古生代构造混杂岩带和巴颜喀拉山三叠纪浊积盆地5个次级构造单元,重新厘定了东昆仑不同构造混杂岩带的组成、结构、性质和时代,恢复了,古海盆的演化历史:通过成分分析和颗粒裂变径迹年龄分析,确定了测区巴颜喀拉山群物源来自北部,基底性质可与马尔争-布青山带相对比,恢复了巴颜喀拉山群经历的构造热历史。运用构造年代学分析方法限定了测区经历的几次重大地质历史转折事件。确定了测区浆混花岗岩的存在。通过构造地貌和第四纪沉积分析,揭示了测区第四纪成山作用过程、水系变迁过程和占环境古气候演变过程。新发现一中型砂岩型铜矿。  相似文献   

4.
王国灿  拜永山 《地球科学》1999,24(2):129-133
东昆中断裂带中存在多期蛇绿岩组合,分别代表中元古代、新元古代-早古生代和晚古生代3次裂解成洋、断裂带中主要的3类各不相同的韧性剪切构造变组合分别可与新元古代早期,加里东期末和晚海西期的3次碰撞缝合事件相匹配,“东昆中蛇绿混杂岩带”不能仅限于东昆中断裂带,而应包括原东昆中蛇绿混杂岩带和整个东昆南单元,是一多旋回俯冲碰撞的复全蛇绿构造混杂岩带,东昆中断和为统一的纵贯东昆仑造山带的线性构造变形带地印支期  相似文献   

5.
青藏高原中的古特提斯体制与增生造山作用   总被引:28,自引:12,他引:16  
青藏高原古特提斯体系的特征表现为古特提斯洋盆中多条状地体的存在,多俯冲、多岛弧增生体系的形成和多地体汇聚、碰撞造山的动力学环境,其构架包括4条代表古特提斯洋壳残片的蛇绿岩或蛇绿混杂岩(昆南-阿尼玛卿蛇绿岩带、金沙江-哀牢山-松马蛇绿岩带、羌中-澜沧江-昌宁-孟连蛇绿岩带和松多蛇绿岩带)、5条火山岩浆岛弧带(布尔汗布达岛弧岩浆带、义敦火山岩浆岛弧带、江达-绿春火山岛弧带、东达山-云县火山岛弧带和左贡-临沧岛弧-碰撞岩浆带)、4个陆块或地体(松潘-甘孜地体、羌北-昌都-思茅地体、羌南-保山地体)、3条洋壳深俯冲形成的高压-超高压变质带(金沙江得荣高压变质带、龙木错-双湖高压变质带、松多高(超)压变质带),以及5条弧前增生楔或增生杂岩(西秦岭增生楔、巴颜喀拉-松潘-甘孜增生楔、金沙江增生楔、双湖-聂荣-吉塘-临沧增生楔、松多增生杂岩)。古特提斯洋盆的俯冲增生造山作用普遍存在于青藏高原古特提斯复合造山体中,构成与多条古特提斯蛇绿岩带(缝合带)相伴随的俯冲增生杂岩带(链)。古特提斯俯冲增生杂岩带包括由弧前强烈变形的沉积增生楔、以及高压变质岩、岛弧岩浆岩、蛇绿岩和外来岩块组成的混杂体,代表在洋盆俯冲过程中的活动陆缘的地壳增生。  相似文献   

6.
东昆中构造混杂岩带是经历了晚元古代、加里东末和晚海西期三次碰撞事件而形成的多旋回复合碰撞缝合带,通过对东昆中构造混杂岩带晚加里东期左旋斜冲韧性剪切变形的几何学、运动学及流变学特征的研究,探讨了其形成的构造背景,指出该期构造变形是东昆中加里东末碰撞事件的产物。  相似文献   

7.
东昆中断裂带中存在多期蛇绿岩组合,分别代表中元古代、新元古代-早古生代和晚古生代3次裂解成洋.断裂带中主要的3类各不相同的韧性剪切构造变形组合分别可与新元古代早期、加里东期末和晚海西期的3次碰撞缝合事件相匹配."东昆中蛇绿混杂岩带"不能仅限于东昆中断裂带,而应包括原东昆中蛇绿混杂岩带和整个东昆南单元,是一多旋回俯冲碰撞的复合蛇绿构造混杂岩带.东昆中断裂带作为统一的纵贯东昆仑造山带的线性构造变形带应形成于印支期陆内构造变形阶段,是碰撞后的陆内构造变形产物.  相似文献   

8.
迄今为止,位于扬子地块的西北缘,夹持于扬子、华北、塔里木和羌塘—昌都地块之间呈倒三角形构造区块的巴颜喀拉褶皱带尚未有构造古地磁研究成果报导。为配合该区油气勘查与油气资源评价,并对构造区块定位提供定量数据,开展了松潘—阿坝地块的古地磁研究。采样区集中在西秦岭构造区南亚带(摩天岭和若尔盖)、中亚带(洮河)和巴颜喀拉构造区的马尔康复向斜带(巴颜喀拉褶皱区)4个微地块。采样地层单元主要为三叠系。共采集57个采点,376块岩心标本。通过对岩石样品测试数据的分析和计算,获得洮河、巴颜喀拉、摩天岭和若尔盖(后两者夹于前两者之间)4个微地块古地磁极极点位置:经度为191.4°E~202.9°E,纬度为49.5°N~58.5°N。洮河和巴颜喀拉两微地块在晚三叠世的古纬度同为26.2°N,表明晚三叠世这4个被断裂相隔的微地块已构成一个统一的较大的地块。洮河和巴颜喀拉地块在三叠纪时的古纬度变化分别从早三叠世的13.4°N和11.3°N向北移动到晚三叠世的26.2°N,同时在北向移动过程中从早三叠世至晚三叠世分别发生了约40°和16°的逆时针旋转。  相似文献   

9.
布青山蛇绿混杂岩位于阿尼玛卿带西段,它是由早古生代和早石炭世一早二叠世两期蛇绿岩组成的复合蛇绿混杂岩带。蛇绿岩中的变质橄榄岩以方辉橄榄为主,高镁,∑PEE是球粒陨石的0.2-0.65倍,HREE是球粒陨石的0.28-0.32倍,属亏损的大洋岩石圈地幔。早古生代蛇绿岩中辉长岩、辉绿岩和玄武岩等镁铁质岩主要具N-MORB性质,少量具T-MORB性质。早石炭世一早二叠世蛇绿岩中玄武岩也主要具N-MORB性质、少量具T-MORB性质。它们均形成于洋中脊环境。本区曾存在成熟的早古生代洋盆和古特提斯洋盆,有更复杂的构造演化史。  相似文献   

10.
东昆仑中部构造混杂岩带右行走滑韧性剪切变形特征   总被引:1,自引:0,他引:1  
东昆仑中部构造混杂岩带是经历了新元古代、加里东末期和晚海西期3次碰撞事件而形成的多旋回复合的碰撞缝合带。通过对东昆中构造混杂岩带晚海西期右行走滑韧性剪切变形的几何学、运动学及流变学特征的研究,探讨了其形成的动力学背景,指出东昆中晚海西期的碰撞缝合带是不同陆块间斜向碰撞形成的转换挤压带。  相似文献   

11.
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   

12.
Well investigated platforms have been selected in each continent, and the history of Cretaceous transgressions and regressions there is concisely reviewed from the available evidence. The factual records have been summarized into a diagram and the timing of the events correlated between distant as well as adjoining areas.On a global scale, major transgressions were stepwise enlarged in space and time from the Neocomian, via Aptian-Albian, to the Late Cretaceous, and the post-Cretaceous regression was very remarkable. Minor cycles of transgression-regression were not always synchronous between different areas. Some of them were, however, nearly synchronous between the areas facing the same ocean.Tectono-eustasy may have been the main cause of the phenomena of transgression-regression, but certain kinds of other tectonic movements which affected even the so-called stable platforms were also responsible for the phenomena. The combined effects of various causes may have been unusual in the Cretaceous, since it was a period of global tectonic activity. The slowing down of this activity followed by readjustments may have been the cause of the global regression at the end of the Cretaceous.  相似文献   

13.
The Afyon stratovolcano exhibits lamprophyric rocks, emplaced as hydrovolcanic products, aphanitic lava flows and dyke intrusions, during the final stages of volcanic activity. Most of the Afyon volcanics belong to the silica-saturated alkaline suite, as potassic trachyandesites and trachytes, while the products of the latest activity are lamproitic lamprophyres (jumillite, orendite, verite, fitztroyite) and alkaline lamprophyres (campto-sannaite, sannaite, hyalo-monchiquite, analcime–monchiquite). Afyon lamprophyres exhibit LILE and Zr enrichments, related to mantle metasomatism.  相似文献   

14.
正20140751 Guo Xincheng(Geological Party,BGMRED of Xinjiang,Changji 831100,China);Zheng Yuzhuang Determination and Geological Significance of the Mesoarchean Craton in Western Kunlun Mountains,Xinjiang,China(Geological Review,ISSN0371-5736,CN11-1952/P,59(3),2013,p.401-412,8  相似文献   

15.
正20141058 Chen Ling(Key Laboratory of Mathematical Geology of Sichuan Province,Chengdu University of Technology,Chengdu610059,China);Guo Ke Study of Geochemical Ore-Forming Anomaly Identification Based on the Theory of Blind Source Separation(Geosci-  相似文献   

16.
SEISMIC GEOLOGY     
正20141334 Chen Kun(Institute of Geophysics,China Earthquake Administration,Beijing100081,China);Yu Yanxiang Shakemap of Peak Ground Acceleration with Bias Correction for the Lushan,Sichuan Earthquake on April20,2013(Seismology and Geology,ISSN0253-4967,CN11-2192/P,35(3),2013,p.627-633,2 illus.,1 table,9 refs.)Key words:great earthquakes,Sichuan Province  相似文献   

17.
正20141624 Cai Xiongfei(Key Laboratory of Geobiology and Environmental Geology,Ministry of Education,China University of Geosciences,Wuhan 430074,China);Yang Jie A Restudy of the Upper Sinian Zhengmuguan and Tuerkeng Formations in the Helan Mountains(Journal of Stratigraphy,ISSN0253-4959CN32-1187/P,37(3),2013,p.377-386,5 illus.,2 tables,10 refs.)  相似文献   

18.
PALEONTOLOGY     
正20142263Lü Shaojun(Geological Survey of Jiangxi Province,Nanchang 330030,China)Early-Middle Permian Biostratigraphical Characteristics in Qiangduo Area,Tibet(Resources SurveyEnvironment,ISSN1671-4814,CN32-1640/N,34(4),2013,p.221-227,2illus.,2tables,22refs.)Key words:biostratigraphy,Lower Permian,Middle Permian,Tibet  相似文献   

19.
正20142560Hu Hongxia(Regional Geological and Mineral Resources Survey of Jilin Province,Changchun 130022,China);Dai Lixia Application of GIS Map Projection Transformation in Geological Work(Jilin Geology,ISSN1001-2427,CN22-1099/P,32(4),2013,p.160-163,4illus.,2refs.)  相似文献   

20.
GEOCHEMISTRY     
正20140692 Duo Tianhui(No.402 Geological Team,Exploration of Geology and Mineral Resources of Sichuan Authority,Chengdu611730,China);Wang Yongli Computer Simulation of Neptunium Existing Forms in the Groundwater(Computing Techniques for Geophysical and Geochemical Exploration,ISSN1001-1749,CN51-1242/P,35(3),  相似文献   

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