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1.
对20世纪90年代国外花岗岩类研究几个方面的进展情况进行了评述：I型／S型花岗岩成因的新模式、磁铁矿系列、钛铁矿毓花岗岩成因、从ISAM到以综合标志为基础的新的花岗岩地球动力学分类、从以大陆边缘板块俯冲带为主扩大到大陆内部碰撞造山带的花岗岩研究地域及太古宙TTG成因，并力图阐明提出问题和解决问题的思路及着手研究的途径。这些内容表明花岗岩研究已进入一个新的发展阶段，即从以个别岩体、央套为主的研究发展到对全球不同构造背景下的花岗岩进行地球动力学研究。作为地壳重要组成的花岗岩物质可以作为地球动力学环境的标志及其演化的示踪剂，反演出不同地球动力学环境下大陆地壳的形成和再循环过程。 相似文献
2.
中国地质调查局花岗岩地质研究室 《岩石矿物学杂志》2002,21(2)
花岗岩是大陆地壳重要的物质组分 ,是壳幔相互作用和造山作用不同阶段的产物 ,是形成众多矿产的物源 ,是揭示地球深部信息的岩石探针 ,是判别地球动力学环境的主要标志。中国花岗岩类型众多 ,特色鲜明 ,时空分布广泛 ,形成环境复杂 ,在全球地质研究中具有举足轻重的地位。目前 ,国外花岗岩地质研究发展迅速 ,已成为大陆地壳生长和地球动力学研究领域不可缺少的重要内容之一。刚刚成立的中国地质调查局花岗岩地质研究室是中国地质调查局业务支撑体系的重要组成部分 ,以“综合、指导、攻关、服务”为宗旨 ,肩负着推广花岗岩地质调查与研究的新… 相似文献
3.
大陆花岗岩的地球动力学意义 总被引：6，自引：0，他引：6
大陆花岗岩的地球动力学意义是一个有争议的话题。笔者认为,花岗岩可分为大洋和大陆两个系列,产于洋盆内及其边缘的花岗岩属于大洋系列,产于大陆内(不包括造山带)的花岗岩属于大陆系列。大洋系列花岗岩最重要的地球动力学意义是判断花岗岩形成的构造环境;大陆系列花岗岩最重要的地球动力学意义是判断地壳状况,包括花岗岩形成时的地壳厚度和温度状况。花岗岩按照Sr-Yb含量可分为埃达克型、喜马拉雅型、浙闽型、广西型和南岭型5类。产于大陆内的不同类型的花岗岩与其形成的深度有关:埃达克型花岗岩富Sr贫Yb,与榴辉岩相处于平衡,产于加厚的地壳;喜马拉雅型花岗岩贫Sr和Yb,与麻粒岩相处于平衡,产于较厚的地壳;浙闽型(贫Sr富Yb)和广西型(富Sr和Yb)花岗岩与角闪岩相处于平衡,产于正常或较薄的地壳;南岭型花岗岩也与角闪岩相处于平衡,地壳厚度最薄。喜马拉雅型花岗岩属于低温系列,浙闽型花岗岩为中或高温系列,广西型和南岭型花岗岩属于高温系列。埃达克型花岗岩则可以出现在各个温度系列。应用花岗岩分类可以恢复古代地壳厚度和下地壳底部温度状况,还可以追踪某些地区随时间变化地壳厚度和温度变化的情况和趋势。 相似文献
4.
化学地球动力学研究进展 总被引：1，自引：0，他引：1
化学地球动力学是地球化学与地球动力学之间的交叉学科,是20世纪末期地幔地球化学研究的热点和前沿。随着人们对板片-地幔相互作用机制及其地球化学效应的认识,化学地球动力学研究已经从地幔不均一性本身拓展到具体俯冲板片对地幔成分的影响。这个拓展为我们认识地球内部的运作机制、俯冲带壳幔相互作用和地幔不均一性的尺度等重要科学问题做出了重大贡献。本文系统回顾了大洋玄武岩成因与地壳物质再循环、大洋玄武岩源区的岩石学性质、板块俯冲与大洋玄武岩成因、大陆镁铁质超镁铁质岩成因和板片-地幔相互作用以及花岗岩成因与大陆动力学等方面的突出进展,对化学地球动力学领域存在的重要科学问题和今后的研究方向也提出了建议。 相似文献
5.
西天山海西中期花岗岩的地质特征及其构造环境 总被引：4，自引：0，他引：4
海西中期花岗岩是西天山加里东褶皱带内规模最大的一次岩浆活动。本文从岩石学、矿物学、岩石化学和地球化学等方面对该期花岗岩的成因类型、岩浆起源和形成的构造环境进行了探讨，认为海西中期花岗岩以Ｉ型为主，Ｓ型次之，在空间上成对分布；花岗岩浆起源于地壳；海西中期花岗岩形成于活动大陆边缘岛弧环境。 相似文献
6.
正作为指示地壳伸展构造背景的重要标志之一,A型花岗岩因其特殊的地球化学特征、岩石成因及地球动力学背景,倍受国内外学者关注,其中A_1型代表了裂谷或板内伸展有关的非造山伸展环境,A_2型则代表了岛弧、后碰撞、陆内剪切等后造山背景下的伸展(Eby,1992)。洪大卫等(1995)也提出拉张程度的差异是产生非造山和后造山A型花岗岩的重要因素。因此,A型花岗岩的成因研究可为约束区域构造演化提供重要依据。 相似文献
7.
大陆构造与动力学研究的若干重要方向 总被引：5，自引：2，他引：5
为了建立新的地球观，当代地学界把主要科学目标瞄准大陆动力学。大陆构造是大陆动力学的核心领域，涉及到盆地和造山带的形成与演化、大陆岩石圈三维层块结构、大陆下地壳的热状态和流变状态、大陆地震成因和大陆地壳运动的动力来源等一系列重大课题。随着多学科的联合攻关和新技术、新方法的应用，在上述研究领域取得的新突破将导致大陆动力学新理论的诞生，并推动固体地球科学迅速发展，以至带来新的地学革命。 相似文献
8.
花岗岩与大地构造 总被引：6，自引：2，他引：4
花岗岩(广义)是地球有别于其它星球及地球上大陆地壳有别于大洋地壳的物质标志,是大陆上分布最广的岩石之一。在已有研究基础上,本文系统阐述了花岗岩大地构造的内涵、研究思路、研究内容和发展方向。花岗岩大地构造将花岗岩视为一种构造标志体、地质体,是从花岗岩角度,探索解决大地构造问题,其研究内容可概括为物理特性(构造)、物质组成(岩石地化)和年代学三大方面,具体研究内容包括:(1)巨量花岗岩浆侵位的物理特性变化及其构造意义,包括岩浆上升迁移、汇聚定位及岩体(带)形成/构建过程;(2)花岗岩体变形改造及其构造意义;(3)花岗岩物源与大陆生长及深部结构,以新老物质组成,划分造山带类型;(4)巨型花岗岩带发育过程与大陆聚散,探索超大陆和中小板块聚散的岩浆响应。花岗岩大地构造丰富了大地构造研究内容,也有助深化花岗岩体(带)形成、发育过程和构造背景的认识。它的提出是当今地球科学学科交叉、融合发展的必要。 相似文献
9.
阿尔金和东昆仑造山带中酸性侵入岩地质、地球化学特征及地质意义 总被引：3，自引：0，他引：3
据青藏高原北部1∶25万区域地质调查资料引对阿尔金和东昆仑造山带中主要出露的中酸性侵入岩类岩体地质、岩石地球化学特征进行对比研究,探讨原始古陆系统隶属关系结果得出:岩体类型、岩石类型组合、成岩时代、岩浆系列、岩浆源岩物性及形成的地球动力学背景均可完全进行对比,认为前晋宁和晋宁期S型花岗岩类,可能是在碰撞造山地球动力学背景下,由成年期TTG陆壳局部或循环熔融形成;加里东和华力西期以I型和A型花岗岩类为主,推测是在一种大陆岩石圈伸展减薄或是大陆裂谷动力学背景下,由地幔基性超基性岩浆上侵引起中下地壳岩石局部熔融产生的一种岩浆作用产物,源区可能是副变质类型榴辉岩相和麻粒岩相下地壳结合前人研究成果,初步提出阿尔金和东昆仑造山带古老基底同属一个古陆系统. 相似文献
10.
花岗岩研究与大陆动力学 总被引：27，自引：1，他引：26
花岗岩是大陆地壳的主要物质组成之一 ,蕴含着探索大陆动力学的重要信息。成因研究特别是混合成因研究可以提供探索大陆结构、生长及壳幔相互作用演化的信息 ;花岗岩形成演化揭示了构造动力学演化、大陆动力学演化及壳幔相互作用演化的某些特点 ;岩浆上升、迁移是大陆内部能量传播、物质迁移和调整的一种形式 ;岩浆的聚集及岩体生产方式与大陆块体运动学、动力学密切相关 ;岩体定时、定位对大陆块体时空定位提供了限制条件 ;变形岩体可作为区域应变标志体和时间标志体 ,研究大陆的变形 ,并有助于古老块体早期构造的解析。这些研究涉及到大陆的形成、演化、内部物质再分配、热动力效应和构造变动等动力学等问题 ,是花岗岩研究与大陆动力学研究的结合点。 相似文献
11.
花岗质岩石成因分类研究述评 总被引：5，自引：0，他引：5
由于花岗质岩石类型多 ,分布广 ,差异大 ,因此 ,国内外学者依据不同的判别标准提出了多种花岗质岩石的分类方案。通过对 2 0多种有代表性的分类方案的分析和对比 ,笔者认为 ,Barbarin(1999)提出的花岗岩类成因分类方案较为合理 ,但应补充橄榄玄粗质花岗岩类这一重要类型。文中较详细地介绍了Barbarin (1999)的分类方案 ,论述了含白云母的过铝质花岗岩类 (MPG)、含堇青石的过铝质花岗岩类 (CPG)、富钾的钙碱性斑状钾长石花岗岩类 (KCG)、富角闪石钙碱性花岗岩类(ACG)、岛弧拉斑系列花岗岩类 (ATG)、洋中脊拉斑质花岗岩类 (RTG)、过碱性和碱性花岗岩类(PAG)以及橄榄玄粗质花岗岩类 (SHG)的特征及其形成的地球动力学环境 ,并简要讨论了这种分类方法的优点和意义。 相似文献
12.
《Russian Geology and Geophysics》2014,55(2):153-176
The evolution of Late Paleozoic granitoid magmatism in Transbaikalia shows a general tendency for an increase in the alkalinity of successively forming intrusive complexes: from high-K calc-alkaline granites of the Barguzin complex (Angara–Vitim batholith) at the early stage through transitional from calc-alkaline to alkaline granites and quartz syenites (Zaza complex) at the intermediate stage to peralkaline granitoids (Early Kunalei complex) at the last stage. This evolution trend is complicated by the synchronous development of granitoid complexes with different sets and geochemical compositions of rocks. The compositional changes were accompanied by the decrease in the scales of granitoid magmatism occurrence with time. Crustal metaterrigenous protoliths, possibly of different compositions and ages, were the source of granitoids of the Angara–Vitim batholith. The isotopic composition of all following granitoid complexes points to their mixed mantle–crustal genesis. The mechanisms of granitoid formation are different. Some granitoids formed through the mixing of mantle and crustal magmas; others resulted from the fractional crystallization of hybrid melts; and the rest originated from the fractional crystallization of mantle products or the melting of metabasic sources with the varying but subordinate contribution of crustal protoliths. Synplutonic basic intrusions, combined dikes, and mafic inclusions, specific for the post-Barguzin granitoids, are direct geologic evidence for the synchronous occurrence of crustal and mantle magmatism. The geodynamic setting of the Late Paleozoic magmatism in the Baikal folded area is still debatable. Three possible models are proposed: (1) mantle plume impact, (2) active continental margin, and (3) postcollisional rifting. The latter model agrees with the absence of mafic rocks from the Angara–Vitim batholith structure and with the post-Barguzin age of peralkaline rocks of the Vitim province. 相似文献
13.
花岗岩成矿的几个判别标志 总被引：14，自引：1，他引：14
花岗岩具成矿专属性。在不同大地构造背景及造山作用不同阶段，不同源岩的部分熔融形成类型、矿物学和地球化学成分、成因、分异演化均不同的花岗岩类，出现不同程度的环带构造、断裂构造和交代作用现象，它们均与相关的成矿元素组合具有一定的相关关系，对花岗岩成矿起关键性的控制作用。本文归纳总结了花岗岩成矿的几个判别标志：大地构造背景、花岗岩的环带构造、成矿流体可迁移性及自交代作用、矿物学和地球化学特征。 相似文献
14.
The dike belt and separate intrusive bodies of the Abdar–Khoshutula series were formed in the NE-trending linear zone, southwest of the Daurian–Khentei batholith, in the peripheral part of the Early Mesozoic magmatic area, on the western termination of the Mongol–Okhotsk belt. The granitoids of this series are subdivided into following geochemical types: anatectic granitoids of the calc-alkaline and subalkaline series, alkaline rocks, and plumasite rare-metal leucogranites (Li–F granites). The entire series was formed within approximately 12–15 Ma. Its geochemical evolution follows two trends, which correspond to two stages of the granitoid magmatism. The early stage was responsible for the formation of granitoids of two phases of the Khoshutulinsky Pluton and alkaline syenites with similar trace element distribution patterns. However, syenites, as agpaitic rocks, are significantly enriched in Ba, Zr, and Hf. The late stage of the intrusive- dike series resulted in the formation of the dike belt and Abdar Massif of rare-metal granites. These rocks show enrichment in Li, Rb, Cs, Nb, Ta, Sn, and Y, and deep negative anomalies of Ba, Sr, La, and Ce, which are best expressed in the late amazonite–albite granites of the Abdar intrusion and ongonites of the dike belt. The intrusive-dike series in the magmatic areas of different age of Mongolia and Baikal region are characterized by the wide compositional variations, serve as important indicators of mantle-crustal interaction and differentiation of granitoid magmas, and could highlight the nature of zonal areas within the Central Asian Fold Belt. Obtained geochemical data indicate a potential opportunity to concentrate trace and ore components during long-term evolution of the intrusive-subvolcanic complexes, which could be indicators of the evolution of the ore-magmatic systems bearing rare-metal mineralization. 相似文献
15.
This paper presents a study of Middle Paleozoic, Late Paleozoic, Early Cretaceous, and Early—Late Cretaceous granitoid complexes from two Pacific marginal seas. The granitoid complexes are subdivided into two large groups: (1) mantle-crust derivatives, including andesite differentiates, and (2) crustal palingenetic granites. In terms of formation depth, they are subdivided into abyssal, mesoabyssal, and hypabyssal granites, with decreasing depth from the old to young complexes. It was established that the granitoids of different genesis have peculiar geochemical features. The granitoids of distinguished genetic types differ in the content and proportions of alkalis, primarily, K, as well as Rb, Sr, and Ba. The palingenetic granites show the predominance of K over Na and are classified as high-K calc-alkaline rocks, whereas andesitic derivatives correspond to the calc-alkaline rocks. The former are characterized by the higher Rb and Ba contents, which is related to the geochemical affinity of these elements to K. In contrast, the Okhotsk Sea rocks are characterized by the predominance of Na over K, the elevated Sr content, and the lower Ba and Rb contents. In terms of geodynamic setting, the studied granitoids fall in the field of volcanic arcs and syncollisional rocks. The latters are represented by the palingenetic granitoids of the Sea of Japan. 相似文献
16.
东准噶尔北缘两类花岗质岩石及其地质意义 总被引：1，自引：0，他引：1
对东准噶尔北缘造山带内花岗质岩石以岩石地球化学特征为主的对比研究发现,该区主要存在两类花岗质岩石：造山带钙碱性花岗岩类和富碱花岗岩类。部分钙碱性花岗岩与新疆北部的埃迭克质岩具有相似的岩浆亲和性,而富碱花岗岩更多的表现出碱性花岗岩的岩石地球化学特点？两类花岗质岩石分别产于大陆碰撞造山带造山演化的俯冲环境和陆内后碰撞环境,... 相似文献
17.
The paper reports the characterization of density, magnetic susceptibility, magnetic anisotropy, seismic wave velocities, attenuation as well as mineralogy and major element chemistry of the four generation of granitoids from the Indian Himalaya. Based on these petrophysical properties, only the Cretaceous granitoids of the Trans-Himalayan region by virtue of their mantle affinity and domination of magnetite and/or magnetite–ilmenite series qualify to be the I-type granitoid. On the other hand, rest of the 3 suites of granitoids have a crustal affinity and can be categorized as S-type granitoids enriched with ilmenite and/or hemo-ilmenite series. Beside this general classification, some anomalous petrophysical properties can be related to distinctive mineralogy, stages of magmatic crystallization, and intensity of deformation in different class of granitoids. For example; (i) presence of heavy minerals like hornblende and magnetite accounts for the significantly high density and seismic wave velocity of the Cretaceous granitoids; (ii) fractional crystallization of mantle melts leads to hornblende-rich granitoids (rich in magnetite) in the earlier stage where biotite-rich granitoids (low magnetite) crystallize in the later stage, thus explaining bimodal distribution of magnetic susceptibility in Cretaceous granitoids; (iii) in S-type granitoids, high quartz content (45%) account for the lowest density recorded in Saruna Proterozoic granitoids whereas high content of micaceous minerals reduce the seismic wave and are responsible for the lowest S-wave velocity in the Early Palaeozoic Mandi granitoids; (iv) further, the effect of texture is seen as varying attenuation character of P- and S-waves on grain size. In general, the higher the grain size, the greater the attenuation. Once again Cretaceous granitoids negate this well established relation. Incorporation of this anomalous dependence of physical properties on mineralogical, tectonic fracturing, texture will help the translation of geophysical maps to more a realistic region specific crustal tectonic evolution models. 相似文献
18.
The classical models of adakite formation by melting of basaltic layer of oceanic lithosphere in the subduction zone were verified using geochemical and Sr–Nd isotope data on the Early Paleozoic granitoids of Eastern Sayan. The presence of adakites in fold belts is usually regarded as geochemical proxy for paleogeodynamic reconstruction. The formation of felsic derivatives with adakitic signatures in the collisional orogens is inconsistent with these models and requires their revision. It is shown that the composition of the granitoids and their evolution cannot be described with these models. In order to solve this problem, two hypotheses of granitoid formation by mixing of two geochemically contrasting reservoirs were proposed and verified. According to the first hypothesis, the granitoids represent the mixing products between alkaline olivine basalts and partial melts of the gray gneiss basement of this region. The second model relates the formation of the granitoids with melting of geochemically 2700 Ma-old enriched source in the subcontinental lithospheric mantle. In spite of differences, both these hypotheses are based on the remobilization of sources formed at the previous stages of the geological evolution of the region. In both cases, adakitic geochemical characteristics of forming felsic magmas are determined by the composition of protolith rather than by their geodynamic position. Obtained preliminary results place constraints on genetic models and geochemical reservoirs participating in the formation of the granitoids. 相似文献
19.
侵入岩填图方法体系及专题研究 总被引：2，自引：1，他引：1
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
20.
《International Geology Review》2012,54(1):71-94
AbstractThe granitoid suites encountered by drilling in the northern South China Sea (SCS) remain important for understanding the evolution of the late Mesozoic Southeast Asian continental margin. They comprise a range of rock types including diorite, tonalite, granodiorite, monzogranite and syenogranite with SiO2 spanning 56.4–76.8%. Newly acquired secondary ion mass spectrometry (SIMS) U–Pb ages of samples from 14 boreholes indicate two key magmatic episodes: Late Jurassic (161.6–148.2 Ma) and Early Cretaceous (136.5–101.7 Ma). Jurassic magmatism probably began in late Middle Jurassic time, documented by the dates of inherited zircons. The granitoids are dominated by metaluminous to weakly peraluminous I-type granites, are transitional between magnesian and ferroan, and encompass calc-alkaline, high-K calc-alkaline, and shoshonitic series. The geochemical signatures suggest that these granitoids were mostly generated in a normal continental arc environment. Notable features of the I-type samples are well-defined negative Nb–Ta–Ti anomalies typical of arc-related magmas. Taken together, the late Mesozoic arc granites of the SCS, the accretionary wedge of the Palawan terrane to the southeast, and the zone of lithospheric extension north of the SCS throughout Southeast China, define a southeast-to-northwest trench-arc-backarc architecture for the late Mesozoic Southeast Asian continental margin whose geodynamic setting is related to subduction of the Palaeo-Pacific slab beneath the Asian continent. Two key subduction episodes are recognized, one in Late Jurassic and the other in Early Cretaceous time. 相似文献