共查询到20条相似文献，搜索用时 31 毫秒
1.
HETEROGENEITY OF THE LITHOSPHERE IN TIBETAN PLATEAU ON THE CONSTRAINTS OF MAGMATISM 相似文献
2.
STUDY ON THE ISOTOPIC CHRONOLOGY AND THE TECTONIC SIGNIFICANCE OF DUGUER GRANITIC GNEISS IN CENTRAL QIANGTANG, TIBET 相似文献
3.
羌塘南部地区大面积出露基性—超基性火成岩。基性岩墙和玄武岩沿龙木错-双湖板块缝合带的南侧呈近东西向分布,大地构造位置位于冈瓦纳大陆北缘,分布范围西起国境线,东到双湖地区,总长约800km,形成时代集中在晚石炭世—早二叠世(284~318Ma),反映出岩浆的快速侵位-喷溢的过程。基性岩墙和玄武岩主要为碱性系列岩石,少数为亚碱性系列,Ti和Fe的含量均比较高,Mg#比较低,表明它们都是原始岩浆经不同程度分异结晶后的残余熔体。基性岩墙和玄武岩的稀土元素、微量元素、形成环境等均与板内玄武岩或典型的地幔柱成因玄武岩具有相似的特点。另外,苦橄质岩石多与基性岩墙和玄武岩一起产出,主要为单斜辉石橄榄岩和二辉橄榄岩,矿物成分贫挥发性组分,主量、稀土和微量元素的特点反映出其很可能代表了地幔柱原始岩浆结晶的产物而非岩浆捕获体,而且其源区很可能为石榴子石二辉橄榄岩。由此,初步认为羌塘南部基性岩墙和玄武岩为地幔柱的头部减压熔融的产物,而苦橄质岩石为地幔柱尾柱通道熔融的产物。 相似文献
4.
羌塘南部地区大面积出露基性—超基性火成岩。基性岩墙和玄武岩沿龙木错-双湖板块缝合带的南侧呈近东西向分布,大地构造位置位于冈瓦纳大陆北缘,分布范围西起国境线,东到双湖地区,总长约800km,形成时代集中在晚石炭世—早二叠世（284～318Ma）,反映出岩浆的快速侵位-喷溢的过程。基性岩墙和玄武岩主要为碱性系列岩石,少数为亚碱性系列,Ti和Fe的含量均比较高,Mg#比较低,表明它们都是原始岩浆经不同程度分异结晶后的残余熔体。基性岩墙和玄武岩的稀土元素、微量元素、形成环境等均与板内玄武岩或典型的地幔柱成因玄武岩具有相似的特点。另外,苦橄质岩石多与基性岩墙和玄武岩一起产出,主要为单斜辉石橄榄岩和二辉橄榄岩,矿物成分贫挥发性组分,主量、稀土和微量元素的特点反映出其很可能代表了地幔柱原始岩浆结晶的产物而非岩浆捕获体,而且其源区很可能为石榴子石二辉橄榄岩。由此,初步认为羌塘南部基性岩墙和玄武岩为地幔柱的头部减压熔融的产物,而苦橄质岩石为地幔柱尾柱通道熔融的产物。 相似文献
5.
SIGNIFICANCE AND CHARACTERISTICS OF OPHIOLITE SUITE IN LAJI SHAN, SOUTHERN QILIAN MOUNTAINS, QINGHAI PROVINCE,CHINAthedoctoralprogramofhighereducation (970 49119) 相似文献
6.
ANISOTROPIC FEATURE OF QIANGTANG MASSIF TEXTURE 总被引：2，自引：1，他引：1
ANISOTROPIC FEATURE OF QIANGTANG MASSIF TEXTURE 相似文献
7.
THE CHARACTERISTICS OF REMOTE SENSING TECTONICS IN QIANGTANG-CHANGDU MASSIF, QINGHAI-TIBET PLATEAU 相似文献
8.
GEOLOGICAL EVOLUTION AND OROGENY OF EAST KUNLUN TERRAIN ON THE NORTHERN QINGHAI—TIBET PLATEAU 总被引：1，自引：0，他引：1
GEOLOGICAL EVOLUTION AND OROGENY OF EAST KUNLUN TERRAIN ON THE NORTHERN QINGHAI—TIBET PLATEAU1 XuZQ ,YangJS ,ZhangJX ,etal.AcomparisonbetweenthetectonicunitsonthesidesoftheAltunsinistralstrike slipfaultandthemechanismoflithosphericshearing[J] :ActaGeologicaSinica,1999,73:193～ 2 0 5(inChinesewithEnglishabstract) .
2 YangJS ,XuZQ ,LiHB ,Wu ,etal.DiscoveryofeclogiteatthenorthernmarginofQaidambasin,NWChina[J] .Chi neseScienceBulletin,1998,4 3… 相似文献
9.
THE CRUSTAL STRUCTURE OF NORTHEASTERN TIBET: A RESULT OF RECEIVER FUNCTION ANALYSIS FOR TELESEISMIC P WAVEFORM 相似文献
10.
~(40)Ar-~(39)Ar GEOCHRONOLOGY OF THE SUTURE ZONE, LADAKH, INDIA1 TalatAhmedetal.GeochemicalJournal,1999.
2 HoneggerK ,etal.EarthandPlanetaryScienceLetters,1982 ,6 0 :2 53.
3 SearleMP ,etal.GeologicalSocietyofAmericaBulletin ,1987,98:6 78.
4 SharmaK ,K .PhysicsandChemistryoftheEarth ,1990 ,17( 2 ) :133.
5 Venkatesan ,etal.EarthandPlanetSciLett,1993,119:181.… 相似文献
11.
羌塘盆地晚三叠世古地理格局是研究其沉积演化史和油气资源评价关键基础。通过地层划分对比、沉积相分析、沉积序列等方法,结合最新的地质调查及其研究结果,对羌塘盆地晚三叠世岩相古地理环境进行恢复,并讨论了上三叠统烃源岩基本特征。羌塘盆地晚三叠世受北侧碰撞造山挤压和南侧班公湖—怒江中特提斯洋盆打开双重影响,北羌塘前陆盆地逐渐萎缩消亡,南羌塘则经历走滑作用开始接受沉积。盆地北部的可可西里造山带、东部的岛链状隆起带和中部的中央隆起带为该时期盆地内三个物源区。北部边缘、中央隆起带东部边缘和盆地的中、东部地区,形成滨岸—三角洲相沉积。盆地中西部沉积较稳定的缓坡相碳酸盐岩。南羌塘坳陷的南部,沉积了向上水体逐渐变深的浅海陆棚相沉积物。此时期碳酸盐岩缓坡相区发育的烃源岩,具有高残余有机碳,高成熟度,低残余生烃潜量等基本特征,综合评价属于中等—较好烃源岩,以生气为主。推测多格错仁地区是今后油气勘探的优选目标和首选地区。 相似文献
12.
笔者根据国内外研究进展和区域地质对比,将特提斯中西段的古生代构造域划分为Iapetus-Tornquist洋加里东造山带、Rheic洋华力西期造山带、乌拉尔-天山中亚造山带和古特提斯Pontides-高加索-Mashhad造山带,并提出4个初步认识：（1） Rodinia超大陆在新元古代裂解形成的原特提斯大洋在欧洲以Iapetus和Tornquist缝合带为代表,它们在约420 Ma闭合形成加里东造山带,与我国秦祁昆造山系相似;（2） Rheic洋类似于特提斯东段的龙木错-双湖-昌宁-孟连洋,为古生代的特提斯主大洋,而泥盆纪形成的古特提斯洋实际上为主洋盆衍生的分支洋盆之一,Rheic洋的各分支洋盆在320~310 Ma闭合,形成华力西造山带和Pangea超大陆;（3）南阿尔卑斯Plankogel带、土耳其北部Pontides带和伊朗北部Rasht-Mashhad为古特提斯缝合带,代表泥盆纪—二叠纪的洋盆,晚石炭世—早三叠世丝绸之路岩浆弧与我国羌塘中部的望果山火山弧相对应;（4）特提斯中西段的基梅里造山带和羌塘中部的印支期造山带为古特提斯增生型造山带的典型代表。 相似文献
13.
THE PALEOCURRENT PATTERN OF EARLY TERTIARY REDBEDS IN THE HOH XIL BASIN,NORTHERN TIBET PLATEAU:IMPLICATIONS FOR AN EARLY UPLIFT AND UNROOFING 相似文献
14.
燕辽地区燕山期火成岩与造山模型 总被引：70，自引：2，他引：70
通过与安第斯、青藏北缘、大陆裂谷带火成岩的比较，阐述了燕辽地区燕山期火成岩具活动大陆边缘靠内陆一侧的构造属性。提出了三种可能的母岩浆（玄武质、粗面质与花岗质）以及它们的混合作用是制约以壳幔混合型为主、组成谱系宽的火成岩的主要机制。基于实验岩石学成果，论述了无负Ｅｕ异常的中酸性火成岩类（正长岩、二长岩、石英闪长岩类）形成于加厚陆壳底部（或山根带）。主要基于岩石学成果，讨论了燕山期本区陆壳厚约６０～７０ｋｍ，岩石圈厚约１００～１５０ｋｍ。通过与印支期岩石圈（厚约１５０～２００ｋｍ）的对比，提出了造山岩石圈的拆沉－去根作用，使岩石圈减薄了约５０ｋｍ。由此，提出了一个大洋俯冲与岩石圈拆沉相结合的造山模型，称为华北式（或燕辽式）造山带模型。这一模型不但可以满意地解释为什么弧火成岩属性的岩浆活动可深入远离海沟达一千多公里的内陆地区以及挤压与拉伸交替的反转构造的发育，而且还可以比较满意地解释为什么火成岩组成极性极不明显，伴随岩浆活动的陆壳不断抬升等，并指出燕山期地幔岩石圈减薄，山根仍存在，所以造山后Ａ型花岗岩（指碱性正长岩类）仍保持无负Ｅｕ异常，而本区新生代处于大陆裂谷发育环境，地幔岩石圈与陆壳均减薄。 相似文献
15.
MAGMATIC ACTIVITY RELATED TO LATE PALEOZOIC RIFTING IN CENTRAL QIANGTANG PLATEAU 相似文献
16.
新疆东昆仑鸭子泉蛇绿岩的基本特征及其大地构造意义 总被引：19，自引：2，他引：17
鸭子泉蛇绿岩位于新疆东昆仑祁漫塔格山系中部, 与阿尔金断裂平行产出, 由超基性岩、基性岩和拉斑玄武岩等组成。它侵位于早石炭世含放射虫的深海沉积物中, 可能代表了东昆仑祁漫塔格地区晚古生代的板块俯冲带。蛇绿岩可能来源于俯冲带附近的由小型扩张中心形成的次生洋壳, 之后由于消减作用, 侵位到深海沉积物中, 形成了造山带中的蛇绿岩。 相似文献
17.
羌塘盆地托纳木地区新生代发育规模较大的洞错地堑构造,走向近南北,长度大于80km,由断隆带和断陷盆地组成,并对研究区地貌和水系格局有明显的控制作用。地堑活动始于中新世,现今仍处于活动之中,其形成可能受深部热动力学机制作用制约。沿地堑正断层存在明显的油气异常,对油气藏具有显著的破坏作用,不利于油气的保存。 相似文献
18.
Two Phases of Cenozoic Deformation in Northeastern Tibet: Thrusting Followed by Strike-Slip Faulting 总被引：1，自引：0，他引：1
TWO PHASES OF CENOZOIC DEFORMATION IN NORTHEASTERN TIBET: THRUSTING FOLLOWED BY STRIKE-SLIP FAULTING 相似文献
19.
CARBONATITES FROM THE EASTERN HIMALAYAN SYNTAXIS: PETROLOGY AND TECTONIC IMPLICATIONS 总被引：1，自引：1，他引：0
Most carbonatites occur in relatively stable, intra\|plate areas but some are found to occur in near to plate margins and may be linked with plate separation (Woolley, 1989). Although many carbonatites have been discovered to occur in the orogenic belts in recent years, most of these rocks are related to post\|orogenic magmatism, that is, the rocks occur in the specially extensional setting. Therefore it is unusual that such magmatic rocks occur in the typical convergent environment. Here we report carbonatites and associated ultramafic and mafic rocks in the core of the eastern Himalayan syntaxis. The eastern Himalayan syntaxis consists of three tectonic units: the Gangdise, the Yarlung Zangbo, and the Himalayan units, each of which is bounded by faults (Liu & Zhong, 1997). The Himalayan unit, the northernmost exposed part of the Indian plate, is divided into two complexes, the amphibolite facies complex in the south and the granulite facies complex in the north. The granulite facies complex in the Himalayan unit have been argued to experience high\|pressure metamorphism and represent materials buried to upper\|mantle depths (Liu & Zhong, 1997). The carbonatites and associated ultramafic and mafic rocks only occur in the granulite facies rocks and are divided into two belts: northern and southern belts.The northern belt extends at least 30km, and is about 20km in width. The southern belt extends several kilometers, and is 3km or so in width. Each belt consists mainly of differently compositional dykes, extending parallel to gneissosity of granulite facies gneiss. Carbonatitic agglomerates are observed in the northern belt. From the center of carbonatite dykes to country rocks, five types of rock are observed: the center parts of carbonatites, the rim parts of carbonatites, ultramafic and mafic rocks, altered rocks and country rocks. The gneissosity of country rock was deformed by intrusion of dykes. 相似文献
20.
M. Qasim Jan M. Hassan Agheem Amanullah Laghari Suhail Anjum 《Journal of the Geological Society of India》2017,89(1):91-98
Kharsar hill is one of many granitic plutons comprising the Nagar Parkar igneous complex. The eastern part of the hill is occupied by grey-pink granite (earlier) and the western part by pink granite (later). They are composed of perthite, quartz, and plagioclase, with minor opaque oxide, biotite, titanite, local amphibole, and secondary chlorite, epidote, leucoxene/titanite. The pink granite is characterized by the presence of mafic clots. Both the granitoids are intruded by microgranite/aplite, and porphyritic mafic and rhyolite dykes, locally in swarms. These are abundant in a NE trending 200 m wide zone cutting the entire granite hill. The dykes may extend over 1 km in length and >10 m in thickness, but most are < 100 m in length. The felsic dykes are of several generations; some are associated with the two varieties of granite, others are contemporaneous with the rhyolite and mafic dykes. The mafic dykes can be grouped into two types one of which contains hornblende and the other augite as the principal mafic mineral. Major element analyses suggest that the granitic rocks are metaluminous. The Kharsar granites, like the others in Nagar Parkar, may be an extension of the Malani igneous suite of Rajasthan. The occurrence of bimodal mafic-felsic dykes and petrographic variation in the mafic dykes are briefly discussed. 相似文献