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1.
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   

2.
藏南岗巴-定日地区花岗岩单元特征及构造环境   总被引:10,自引:2,他引:10       下载免费PDF全文
岗巴。定日地区花岗岩属藏南拉轨岗日构造岩浆带的组成部分,岩石类型主要为似斑状二云母二长花岗岩、黑云母二长花岗岩、二长花岗岩、片麻状二云母二长花岗岩。通过1:25万区域地质填图,按照同源岩浆演化序列的观点,根据岩石学、岩石化学及地球化学、接触关系等特征,将该区花岗岩划分为5个单元,归并为1个超单元——佩古错超单元。研究表明,该超单元为S型花岗岩,在岩石学、岩石化学及地球化学组成上具有明显的同源岩浆演化特征,为形成于被动大陆边缘同碰撞构造环境的花岗岩。  相似文献   

3.
童英  郭磊  王涛  张磊  黄河  张建军 《地质通报》2017,36(11):1963-1970
单元-超单元花岗岩谱系填图方法是以同源岩浆演化理论为指导思想建立发展的。该方法从20世纪80年代开始在中国推广和应用,然而,随着岩浆岩理论的不断发展及填图实践过程中遇到的问题,填图方法回归到早期的"岩性+时代"方法。在新的形势下,如何开展好新一轮的花岗岩填图工作,谱系填图是否仍具有适用性值得分析探讨。以中蒙边境地区出露的宝德尔石林花岗岩体填图试点成果为例,阐述岩浆岩填图试点方法的可行性。填图结果显示,该岩体为复式杂岩体,发育约160Ma和140~124Ma两期二长花岗岩,这两期二长花岗岩时代和岩石结构存在差别,野外的主要区别在于粒度。它们处于同一个区域性伸展背景,属于同源岩浆演化的产物。依据谱系划分方案,可以划分为晚侏罗世和早白垩世2个序列及5个单元,且可以进行区域对比。因此,基于岩浆演化规律,以解体岩体和进行岩石类型归并为精髓的谱系填图对于同源花岗岩仍是适用和必须的,但不可扩大化。  相似文献   

4.
侵入岩填图方法体系及专题研究   总被引:2,自引:1,他引:1  
王涛  童英  郭磊  张建军  苏尚国  焦建刚  王连训 《地质通报》2017,36(11):1953-1962
中国侵入岩填图经历了不同发展阶段。目前,需要探索中大比例尺(1∶5万~1∶2.5万)填图方法。依据以往的填图实践经验,特别是同源花岗岩、异源花岗岩、中基性岩、超基性岩试点填图,提出侵入岩填图方法体系。无论何种成因,侵入岩填图应该建立不同级别的等级体制填图单位,即侵入体-单元-序列(或岩套)-超序列(或超岩套)-超序列组合(或超岩套组合),分别对应岩体-岩基-岩带-巨型岩带。同源花岗岩岩浆,可以按照以往的谱系单位填图,其侵入体-单元-序列-超序列应该是同一个岩浆旋回演化的产物。岩浆混合花岗岩,可以按照混合程度划分单元,归并序列。中基性-超基性侵入岩,也可以参考上述谱系单位和混合单位填图。侵入岩不同级别等级体制单位的建立有利于深入认识岩浆系统及其制约因素。此外,花岗岩等侵入岩蕴含了丰富的地球动力学信息,有必要开展深入的专题研究。  相似文献   

5.
在花岗岩同源岩浆演化过程中,稀土元素的铕亏损和轻、重稀土的比值可以反映各单元岩浆演化的先后顺序,进而为花岗岩单元─超单元填图提供佐证。  相似文献   

6.
琼南九所—高峰地区花岗岩谱系单位及演化特征   总被引:1,自引:0,他引:1  
王大英  黄怀 《广东地质》1995,10(4):19-25
根据同源岩浆演化的理论,运用单元一超单元的填图方法,将琼南九所-高峰地区的花岗岩分成90个侵入体,建立18个单元,归并为4个超单元,建立了该地区花岗岩的谱系单位,并对其岩石类型,岩石化学的演化特征进行了探讨。  相似文献   

7.
内蒙古中部白垩纪碱性花岗岩的发现及意义   总被引:3,自引:2,他引:3  
罗飞  罗照华 《现代地质》1995,9(2):203-211
作者通过对内蒙古苏尼特左旗地区深成侵入岩类同源岩浆演化系列的研究,首次发现了一个典型的碱性花岗岩杂岩体.在详细的地质填图和室内研究的基础上,按照岩石谱系单位的划分原则,对其作了进一步的解体,并对该碱性花岗岩超单元的岩石学、矿物学、岩石化学以及稀土元素地球化学进行了综合研究.同时,对杂岩体的成因性质及岩浆起源的物化条件作了初步探讨。认为沙尔塔拉碱性花岗岩超单元是形成于早白垩世的A型花岗岩,是该地区造山期后陆壳整体抬升过程中拉张环境下岩浆活动的产物,它的发现将对本区构造岩浆活动发展史的认识具有重要的意义.  相似文献   

8.
夏国礼 《华北地质》2003,26(1):61-64
结合野外实际资料,笔者就花岗岩类谱系单位填图方法能否以岩石结构演化特征为基础建立S型花岗岩的谱系单位,深成岩体间的接触关系类型能否作为划分花岗岩等级体制的标志进行了分析讨论,认为不同深成岩体之间的固结作用时间差仅仅是影响岩石结构变化及深成岩体间接触关系类型的因素之一,更主要的影响因素是与深成岩体形成时的物理化学环境(温度、压力、挥发组分的多寡)以及围岩介质的湿冷度、岩浆上侵规模的大小等有关。因此,S型花岗岩序列内部从早单元到晚单元岩石结构可以出现由粗粒结构一细粒结构演化的现象,同一起单元内部也可以出现起动型接触关系。另外,文中还对与火山岩关系密切的高位深成岩体能否单独建立谱系单位及混合岩浆成因的花岗岩可否利用同源岩浆演化理论建立谱系单位等问题进行了探讨。认为该方法尚有不妥之处,在具体使用过程中应加以注意。  相似文献   

9.
造山带异源浆混花岗岩理论与方法研究   总被引:2,自引:0,他引:2  
1:5万花岗岩填图方法在区调工作中推广以来,在造山带花岗岩调查实践中,由于造山作用及过程的复杂性,花岗岩浆的多源及多样性,使同源岩浆演化理论及方法遇到了难题。文章在新一轮1:25万造山带试点图幅,在对同源岩浆演化理论及方法的适用性进行探索的同时,提出了异源浆混理论指导造山带内部浆混花岗岩(H型花岗岩)的填图方法。并就异源浆混花岗岩鉴别标志等作了系统总结,提出了浆混组合、浆混单元、浆混体,填图的理论方法体系;给予了浆混花岗岩明确的定义。  相似文献   

10.
运用单元—超单元填图新方法对尼木—曲水岩基段进行了解体。建立了26个侵入岩单元,其中归并7个超单元,2个超单元组合。讨论了各超单元内部不同单元之间的演化规律以及岩基段的形成发展。通过各单元、超单元特征研究,确定该区存在四种花岗岩系列,即M型、科迪勒拉I型,加里东I型和S型,后两类系列为该岩基段主体岩石类型,且具同碰撞花岗岩特征。  相似文献   

11.
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.
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.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
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.
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.
PALEONTOLOGY     
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   

16.
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.
PETROLOGY     
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   

20.
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   

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