岩石学报杂志 SCI期刊 北大期刊 CSCD期刊 统计源期刊

岩石学报 2009年第08期杂志 文档列表

变质作用分类的历史回顾和新的试行分类雏议-

摘要：根据变质作用分类研究的历史回顾和最新进展,本文介绍了一个试行的、较系统的变质作用分类方案,可分为局部性的变质作用和区域性的变质作用两个大类9个类型.局部性的变质作用包括以下5个类型:(1)接触变质作用,包括热变质作用、接触交代变质作用和高热变质作用3个亚类;(2)低-中-高温动力变质作用,包括低-中-高温韧性剪切带变质作用和温压递进逆冲断层变质作用2个亚类;(3)冲击变质作用;(4)水热变质作用;(5)燃烧变质作用.区域性的变质作用可分为以下4个类型:(6)早前寒武纪克拉通基底变质作用-低中压-中高温区域变质作用,可分为5个亚类,分别是低-中压角闪岩相变质作用、低-中压麻粒岩相变质作用、低-中压角闪岩相-麻粒岩相变质作用、低-中压绿片岩相-角闪岩相递增的变质作用和区域超高温麻粒岩相变质作用;(7)造山带变质作用,可分为3个亚类,分别是低温-低压区域动力变质作用、碰撞造山变质作用和深俯冲高压-超高压区域变质作用;(8)埋深变质作用;(9)洋底变质作用. Abstract： Based on a history review of the advancement in classification of the metamorphism types, this paper has proposed a tentative and systematic classification of types of metamorphism. Metamorphism can be divided into two great types: Local and regional metamorphism, each of which involves 4 or 5 types. Local metamorphism is divided into the following five types: (1) contact metamorphism which includes three subtypes, i.e. thermal metamorphism, contact metasomatic metamorphism and pyro-metamorphism; (2) low-medium-high temperature dynamic metamorphism involving two subtypes such as low-medium-high temperature ductile shear zone metamorphism and temperature-and pressure-increasing thrust metamorphism; (3) impact (or shock) metamorphism; (4) hydrothermal metamorphism; (5) burn metamorphism. Regional metamorphism is divided into the following four types; (6) Early Preca

包含变质岩分类三要素的主要变质岩分类表-

摘要：变质岩分类的三要素是:变质岩的物质成分(化学成分、矿物成分)、变质岩的组构(结构、构造)和变质岩的成因(变质作用类型和形成变质岩的物理化学条件).由于变质岩的化学成分、矿物成分、组构特征和形成变质岩的地质环境十分复杂,致使至今尚无以变质岩分类三要素为基础的、内容比较完善的分类方案.本文中主要变质岩的分类是以其分类三要素为基础编制的,首次将不同成因的变质岩类并列于同一表中、将鉴定变质岩的主要标志性矿物成分和组构特征列入同一分类表中.该分类对鉴定变质岩石具有可操作性和实用性,分类表中涵盖了自然界主要的变质岩石. Abstract： The three essential factors for classifying metamorphic rocks are composition (chemical and mineralogical), fabric (texture and structure) and genesis (types of metamorphism and physiochemical conditions for forming metamorphic rocks). So far, there is still not a perfect classification scheme based on the three essential factors due to the chemical, mineralogical and fabric characteristics, and the complex geological environments of metamorphic rocks. The classification scheme used in this paper is based on the three essential factors. For the first time, we put metamorphic rocks with different geneses into one classification scheme. We have also listed the main index mineral compositions and fabric characteristics into one classification scheme to indentify metamorphic rocks. Compared to previous schemes, this classification scheme is more useful and practicable, which has covered the main metamorphic rocks in nature.

东南极普里兹带多期变质作用及其对罗迪尼亚和冈瓦纳超大陆重建的启示-

摘要：东南极普里兹带是一条经受格林维尔期和泛非期高级构造热事件影响的多相变质带,其构造演化过程与罗迪尼亚和冈瓦纳超大陆的形成密切相关.新的岩石学和年代学资料表明,普里兹带中的格林维尔期高级变质作用是区域性的,并经历了>970Ma和930～900Ma两个演化阶段(期),变质条件达到相对高温高压的麻粒岩相.格林维尔期造山作用起始于活动大陆边缘或岛弧环境下的岩浆增生,最后发展到陆陆碰撞,从而使印度、东南极西陆块和非洲的卡拉哈里克拉通拼合在一起,构成了罗迪尼亚超大陆的重要组成部分之一.普里兹带中的泛非期高级变质作用并不象前人认为的那样只发生在中低压麻粒岩相条件下,而是达到高压麻粒岩相,并具有近等温减压的顺时针P-T演化轨迹.格林维尔期变质先驱的普遍存在说明泛非期碰撞造山事件主要叠加在印度-南极陆块东缘的基底杂岩之上,所以其主缝合线的位置应该在现今普里兹带的东南方向,并可能向南极内陆延伸到甘布尔采夫冰下山脉.对不同类型岩石的精细定年揭示,普里兹带中泛非期造山作用过程从570Ma一直持续到490Ma,这与东非造山带的晚期碰撞阶段大致相吻合.因此,冈瓦纳超大陆的最后拼合可能是通过西冈瓦纳、印度-南极陆块和澳大利亚-南极陆块等三个陆块的近于同期碰撞来完成的. Abstract： The Prydz Belt in East Antarctica is a typical polymetmorphic belt that experienced Grenvillian and Pan-African high-grade metamorphism. The tectonic evolution of the belt is closely related to the formation of the supercontinents Rodinia and Gondwana. New petrological and geochronological data suggest that the Grenvillian metamorphism involving two episodes at>970Ma and 930～900Ma spreads over the main part of the Prydz Belt. Metamorphic peak during this peroid reaches relatively high temperature and high pressure granulite facies conditions. The Grenvi

华北克拉通晚中生代壳-幔拆离作用:岩石流变学约束-

摘要：大陆岩石圈的流变学结构对于岩石圈深部过程(壳/幔过程)有着深刻的影响,直接表现在岩石圈壳-幔结构与浅部构造上.本文注意到华北克拉通晚中生代岩石圈减薄期间地壳的伸展、拆离与减薄在不同地区的宏观、微观构造及地壳岩石流变学等方面的差异表现与区域变化,以及现今和晚中生代时期岩石圈厚度的不均匀性.讨论了以水为主体的地质流体的存在对于岩石圈流变性的影响.综合克拉通东部与西部地壳/地幔厚度变化特点以及下地壳和上地幔含水性特点,阐述了晚中生代时期华北克拉通岩石圈内部壳幔耦合与解耦的规律,提出了华北岩石圈壳-幔拆离作用模型以解释华北克拉通晚中生代岩石圈减薄的基本现象与深部过程.提出区域性伸展作用是岩石圈减薄的主要动力学因素,东部地区在晚中生代伸展作用过程中壳-幔具有典型的解耦性,上部地壳、下部地壳和岩石圈地幔的变形具有显著差异性.而西部区壳幔总体具有耦合性,下地壳与岩石圈地幔共同构成流变学强度很高且难以变形的岩石圈根. Abstract： Rheological structure of the continental lithosphere fundamentally influences on the deep processes of the lithosphere (crust/mantle process), which is directly shown by the crust-mantle structure of the lithosphere and also by shallow structures. Crustal extension, detachment faulting and thinning of the crust during thinning of the lithosphere of North China craton in Late Mesozoic are exactly shown by occurrence and variation of macro-and micro-structures, and due to changing rheology of the crust. The inhomogeneity of Late Mesozoic lithosphere is deduced from the present geophysical lithosphere structure and regional structural analysis. Lithosphere rheology is influenced by several factors including the absence and presence of H_2O dominated geological fluids. Coupling and decoupling relationships of the crust and mantle during regional e

内蒙古贺兰山地区古元古代晚期的花岗岩浆事件及其地质意义:同位素年代学的证据-

摘要：位于华北克拉通西缘的贺兰山杂岩主要由孔兹岩系和变形花岗岩(正片麻岩)所组成,前者主要由夕线石榴片麻岩、石榴二长片麻岩、变粒岩和少量的大理岩及麻粒岩所组成,后者主要包括黑云斜长片麻岩、石榴子石花岗岩、斑状花岗岩和片麻状变质闪长岩.本文报道了该区变形花岗岩的锆石SHRIMP U-Pb定年结果.黑云二长片麻岩和石榴子石花岗岩分别形成于2053±58Ma和2047±42Ma,斑状花岗岩和片麻状闪长岩分别在1955Ma和1920Ma侵位.大量的年代学资料表明,在华北克拉通北缘存在一条古元古代晚期的花岗杂岩带,该带中的花岗杂岩主要形成于三个阶段,第一阶段大于2.0Ga,第二阶段主要出现在2.0～1.87Ga期间,第三阶段的花岗杂岩在1.85～1.80Ga期间侵位.年代学研究还表明,古元古代晚期的花岗岩浆作用常常与变质事件紧密相关. Abstract： Helanshan complex, situated in the western margin of the North China Craton, consists mainly of khondlite series and deformed granitoids (orthogneisses). The former is composed dominently of sillimanite-garnet gneiss, garnet two-feldspar gneiss, leptineite and a bit of marble and granulite, the later consists mainly of biotite plagioclase gneiss, garnet granite, porphyritic: granite and gneissic diorite. By using the zircon SHRIMP U-Pb dating, the authors have been obtained some results for granitoids in this area. The biotite feldspar gneiss and garnet granite formed respectivelly 2053±58Ma and 2047±42Ma, respectively,porphyritic granite and gneissic diorite intruded at 1955Ma and 1920Ma respectively. A lot of geochronology data indicate that a Late-Paleoproterozoic granite zone distributes in the northern margin of the North China Craton. The Late-Paleoproterozoic granitoids formed in three stages, the granitoids of the first stage formed early than 2.0Ca, second stage occurred in 2.0～1.87Ca, the granitoids in third stage intruded at 1.85～1.80Ca. The Late-Paleoproterozoic gran

贺兰山孔兹岩系的变质时代及其对华北克拉通西部陆块演化的制约-

摘要：贺兰山孔兹岩系作为华北克拉通西部孔兹岩带的重要组成部分,其变质时代问题一直悬而未决.利用SHRIMP锆石U-Pb定年技术,对贺兰山孔兹岩系中3个代表性富铝片麻岩(石榴堇青钾长片麻岩、石榴堇青二长片麻岩与石榴黑云斜长片麻岩)样品进行了精确定年.发现这3种岩石虽处不同层位,但其碎屑锆石年龄却非常集中,各测点~(207)Pb/~(206)Pb年龄总体变化在2.0～2.1Ga之间,加权平均年龄则在2017～2040Ma之间.这些碎屑锆石都具有岩浆结构特征,反映当时曾存在大规模花岗质岩浆活动,所成岩体为孔兹岩系沉积提供了充足物源.另有少量大于2.5Ga的碎屑锆石(2520～2949Ma),表明本区存在太古代岩浆活动记录.本区石榴堇青二长片麻岩中发育典型的变质增生锆石,其成因很可能与黑云母的脱水熔融反应有关.利用该锆石确定贺兰山孔兹岩系的变质时代为1950±8Ma.该时代与东部大青山、乌拉山孔兹岩系变质时代相同,表明华北克拉通西部的阴山地块与鄂尔多斯地块大体是以平行的方式正面拼贴到一起的,形成了目前的孔兹岩带. Abstract： The khondalite series in the Helanshan region is a main part of the Khondalite Belt in the western block of the North China Craton, whose metamorphic time is still unknown. Using SHRIMP zircon U-Pb dating technique, three representative Al-rich gneiss samples from the Helanshan khondalite series were analyzed, including garnet-cordierite-K-feldspar gneiss, garnet-cordierite monzo-gneiss and garnet-biotite-plagioclase gneiss. The results show that the three rocks have nearly same detrital zircon age though they were collected from different strata. Apparent ~(207)Tpb/~(206)Pb ages of detrital zircons range from 2. 0 to 2. 1Ga and weighted mean ages are from 2017Ma to 2040Ma. According to CL image and Th/U value, all the detrital zircons are magmatic origin, indicating a large scale of granitic intrusion at that time, which could provide en

华北克拉通南缘安沟群的SHRIMP年龄及地层对比-

摘要：华北克拉通南缘安沟群的时代及地层划分对比一直存有争议.侵吞安沟群的许台花岗岩原划为古元古代,本文通过SHRIMP测试,获得其精确的形成年龄为2503±11Ma.安沟群石梯沟组变质酸性火山岩的SHRIMP锆石U-Ph年龄为2521±11Ma,安沟群寨沟组变质酸性火山岩的SHRIMP锆石U-Ph年龄为2517±12Ma,表明安沟群形成于新太古代,与登封群和五台群的形成时代基本一致.安沟群地层的原岩组合为基性火山岩-中酸性火山岩、泥质.碎屑沉积岩和少量碳酸盐岩,总体上与登封群和五台群的原岩组合类似. Abstract： The age, stratigraphic division and correlation of the Angou Group on the southern margin of the North China Cratou have been in dispute for a long time. The crystallization age of the Xutai granite which disrupted the Angou Group was once assigned as Paleoproterozoic. In the paper a precise SHRIMP zircon U-Pb age of 2503±11Ma is obtained for the time. As to the Angou Group themselves, the meta-acid volcanics of the Shitigou Formation and the Zhaigou Formation from the complex give the SHRIMP zircon U-Pb ages of 2521±11Ma and 2517±12Ma, respectively. The data show that the Angou Group formed in Neo-Archaean, which is consistent with the formation age of the Dengfeng Group and Wutai Group. In addition, the protolith association of the Angou Group is similar to that of the Dengfeng Group and Wutai Group, too, including the basic and intermediate-acidic volcanics, argitlitic to detrital sediments and minor carbonate rocks.

沂水杂岩中变泥砂质岩石的岩石化学特征及年代-

摘要：含夕线石十字石榴二云斜长片麻岩是沂水杂岩中首次发现的一种少见的变泥砂质岩石,包裹于沂水生心官庄岩浆杂岩体中,为残留的变质表壳岩透镜体,它经历了两期变质作用的改造.早期高角闪岩相变质与区域麻粒岩相变质有关,峰期矿物共生组合主要为:石榴子石(中心域)+黑云母±白云母+斜长石+石英,M1峰期变质温压条件为:T=660±10℃,P=5.7±0.3kb;晚期角闪岩相变质矿物共生组合为:十字石+石榴子石(边部域)+黑云母±白云母+斜长石±夕线石+石英,以形成大量自形-半自形十字石和具有明显的成分环带的石榴子石为特征,晚期石榴子石的形成由核部→边部经历了一降温降压过程,石榴子石核部:T=650±10℃,P=7.7±0.5Kb,石榴子石边部:T=578±10℃,P=4.7±0.1kb;晚期变质作用早期(石榴子石成核)阶段与埋深导致的部分熔融有关,晚期石榴子石生长阶段与岩浆热事件有关.锆石SHRIMP U-Pb定年结果表明:碎屑锆石不一致线上交点年龄为2695±32Ma,代表变泥砂质岩石源区岩浆岩的结晶年龄,变泥砂质岩石的早期变质变质作用年龄小于此值;晚期变质作用年龄为2537±5Ma. Abstract： A kind of metapelite of sillimanite-bearing staurolite-garnet-two-mica plagiogneiss is recognized at first time, which is as a relic of metamorphic supracrustal rock in the Niuxinguanzhuang magmatic complex. Two metamorphic phases are recognized by assemblage minerals in the rock. The first metamorphic phase (M_1) is of high amphibolite facies, the peak-assemblage minerals include garnet (M_1)+biotite±muscovite+plagioclase+quartz±staurolite, which is related to the regional granulite facies metamorphism. The peak metamorphic conditions estimated by core-component of garnet are about T=660±10℃ and P=5.7±0.5kb respectively. The second metamorphic phases (M_2) is of amphibolite facies which the assemblage minerals include staurolite+garnet (M_2)+biotite±muscovite+plagioclase+sillimanite+quartz

山东沂水杂岩岩石化学及锆石Hf同位素研究-

摘要：山东沂水杂岩主要由高角闪岩相至麻粒岩相变质的变基性岩和(紫苏)花岗岩岩体组成.本文主要研究了三个含紫苏辉石的黑云斜长角闪岩(YS06-19、YS06-41和YS06-29),三个含石榴子石的角闪二辉斜长麻粒岩(YS06-40、YS06-45、YS06-49),一个含尖晶石和石榴子石角闪二辉麻粒岩(YS06-31)和两个英灵山花岗片麻岩样品(YS06-30和YS06-48)的岩石化学和锆石Hf同位素特征.结果认为,(1)含紫苏辉石的黑云斜长角闪岩和含石榴子石的角闪二辉斜长麻粒岩对Sr、K、Rb、Ba、Ce、Th等大离子亲石元素和轻稀土元素的富集程度不同,指示了其原岩经历了不同程度的部分熔融;(2)认为英灵山花岗片麻岩是由来自于亏损地幔的基性岩部分熔融产生,这一观点同沈其韩等(2000)认识一致;(3)所研究的变基性岩的锆石Hf亏损地幔模式年龄均小于英灵山花岗片麻岩Hf亏损地幔模式年龄,指示了该变基性岩可能不是英灵山花岗片麻岩的母岩,沂水地区应该存在更古老的变基性岩石,也可能反映了这两类岩石对Hf同位素体系的保存能力不同;(4)该地区地壳生长在30亿年左右启动,大规模的地壳生长出现在2530～2740Ma. Abstract： Yishui Complex in Shandong Province is mainly composed of meta-basic rocks with high amphibolite facies to granulite facies metamorphism and (hypersthene-bearing) granite bodies. In this article, the authors researched the petrochemical and hafnium isotopic characters of zircons of four kinds of rocks including hypersthene-bearing biotite plagio-amphibolites, garnet-bearing hornblende two-pyroxene plagioclase granulites, spinel and garnet-bearing hornblende two-pyroxene granulites and Yinglingshan granite-gneiss. The research results are as follows: (1) Hypersthene-bearing biotite plagio-amphibolites and garnet-bearing hornblende two-pyroxene plagioclase granulites have different enrichment of St, K, Rb, Ba, Ce, Th and light rare earth elements, these indicate that thei

扬子地台西南缘高家村岩体成因:岩石学、地球化学和年代学证据-

摘要：高家村岩体辉长岩-橄榄岩中矿物组合、矿物结晶顺序及岩浆成因角闪石的普遍出现,指示矿物结晶于富含水的岩浆体系.主量元素Al2O3、CaO与MgO呈明显的负相关关系,表明斜长石并非早期堆晶相.稀土元素含量为5.97×10~(-6)～221.32×10~(-6),轻稀土元素相对富集,弱-中等程度轻重稀土元素分异,辉长岩-含辉石闪长岩无明显的Eu异常,而橄榄辉长岩-橄榄岩具有较明显的正Eu异常.微量元素中,辉长岩-含辉石闪长岩类具有明显的Nb、Ta、Zr、Hf和Ti负异常,Ba、Sr正异常,同时ε_(Nd)(t)为0.59～1.86,低于同期的亏损地幔值,与岛弧基性岩浆特征类似.含辉石闪长岩SHRIMP锆石U-Pb年龄结果822±8Ma,为新元古代.综合分析认为,高家村岩体应形成于受俯冲带流体改造的亏损上地幔部分熔融. Abstract： The mineral assemblage, crystallizing sequence and ubiquitous occurrence of hornblende in the gabhro-peridotite pluton near Gaojiacun Village, Yanbian County, Sichuan Province, all indicate that the rocks formed from the hydrous magma. The obvious negative correlations between the major components Al_2O_3, CaO and MgO imply that plagioclase is not an early cumulate phase. With the total REE contents from 5.97×10~(-6) to 221.32×10~(-6), the LREE are moderately enriched and the LREE and HREE are weak to moderately differentiated. While the Eu anomaly is weak in gabbro and pyroxene-bearing diorite, but prominent in olive-gabbro and peridotite. As to the trace elements, negative anomalies of Nb, Ta, Zr, Hf and Ti, but positive anomalies of Ba and Sr can be observed in the gabbro and pyroxene-bearing diorite. Meanwhile the ε_(Nd) (t)gives the range of 0. 59～1.86, which is lower than that of the contemporaneous depleted mantle, suggesting the similar feature to that of basic magma of the island arc. In addition, the Neoproterozoic age, 822±8Ma, is obtained with SHRIMP U-Pb analysis of zircon from the pyroxene bearing diorite. Summarizingly the Gaojiacun plu

黑龙江桦南地区黑龙江杂岩锆石U-Pb定年-

摘要：黑龙江杂岩主要由绿片岩相变质岩和糜棱岩化构造片岩组成,长期以来与麻山杂岩一起被认为代表佳木斯地块的前寒武纪基底,但这种认识缺乏可信的同位素年代学及古生物资料的支持.对出露于黑龙江省东部桦南地区湖南营组绿片岩进行了锆石LA-ICP-MS U-Pb定年研究.结果显示锆石的Th/U比值为0.27～1.27,变化较大;获得两组~(206)pb/~(238)年龄数据:其加权平均年龄分别为:511±10Ma(n=13,MSWD=1.6)和274.7±3.6Ma(n=9,MSWD=0.91).黑龙江杂岩中最老的年龄969～747Ma表现来自中元古和新元古代.这些年龄与黑龙江杂岩的年龄与来自俯冲碰撞变质事件的～511Ma的年龄结合起来,表明黑龙江杂岩中含有经历晚新元古--早古生代造山作用的碎屑锆石,亦或代表着在俯冲拼贴过程中混入的麻山杂岩块体.～275Ma年龄反映黑龙江杂岩经历的一次碰撞造山事件,可能与晚古生代古亚洲洋闭合相关. Abstract： The Heilongjian complex is consist of greeschist rocks and tectonic mylonites, and has been believed making up of Precambrian basement with the Mashan complex together in northeastern China. This conclusion, however, lacks of evidences of isotopic age and paleontology. LA-ICP-MS zircon U-Pb dating of the greeschist from the Hunanying Formation of the Heilongjian complex is carried out in order to determine the age and to discuss geotectonic background and metamorphic events the Heilongjian complex has experienced. Results show that zircons from analyzed sample present available Th/U ratio between 0.27～1.27 and show well defined two group ages, i. e. weighted average ~(206)pb/~(238)U ages are 511±10Ma (n=13, MSWD=1.6) and 274.7±3.6Ma (n=9, MSWD=0.91). The oldest ages from 969～747Ma imply the origination of Mesoproterozoic to Neoproterozoic. These ages along with metamorphic age of～511 Ma display that the Heilongjian complex, contains detrital zircons, which are possibly derived from the spatially intimately associated Mash

黑龙江依兰地区黑硬绿泥石片岩岩石学与P-T条件研究-

摘要：依兰地区黑龙江杂岩中黑硬绿泥石片岩矿物组合为黑硬绿泥+绿泥石+多硅白云母+钠长石+透闪石+钾长石±黑云母.岩石矿物学研究表明黑硬绿泥石片岩形成于250～400℃,6～9kbar的变质条件下.黄褐色黑硬绿泥石呈束状、放射状集合体.黑硬绿泥石片岩形成于佳木斯地块向西与松嫩地块俯冲拼贴过程中蓝片岩变质作用的后期,压力稍有降低而温度略有升高的变质变形环境,是蓝片岩向绿片岩转变的蓝闪绿片岩相变质条件下的产物. Abstract： Stilpnomelane schist contains mineral assemblage of stilpnomelane + chlorite + phengite + albite + tremolite + quartz + K-feldspar + biotite in Heilongjian complex, Yilan district. Mineralogical and petrological studies show that stilpnomelane schist formed under P-T conditions of 250～400℃ and 6～9kbar. Brown stilpnomelane occurs in the form of fascicular or radial aggregates. Stilpnomelane schist was formed in the process of Jiamusi block westward subduction with Songnen block during post-stage blueschist metamorphism, and was a product of geological deformation environment with pressure slightly decline and temperature slightly increase when blueschist facies transforms into greenschist facies.

黑龙江杂岩的碎屑锆石年代及其大地构造意义-

摘要：黑龙江杂岩带位于佳木斯地体西缘,为佳木斯地体向西与松嫩地体之间俯冲、拼贴、碰撞而形成的高压变质带.黑龙江杂岩沿牡丹江断裂分布,其构造-岩石组合、变质变形特征等显示其为佳木斯地体向松嫩地体俯冲拼帖的过程中形成的增生杂岩,目前保存下来的杂岩带应为大规模增生楔仰冲到佳木斯地体之上的残余部分.88颗碎屑锆石的全部样品SHRIMPU-Ph年代学测试结果显示三个主要年龄区间:170～220Ma,峰值年龄为183Ma;240～338Ma,峰值年龄为256Ma;450～520Ma,峰值年龄为470Ma.而28个碎屑锆石谐和年龄的年龄谱为两组:240～338Ma,峰值年龄为256Ma;450～500Ma,峰值年龄为470Ma.碎屑锆石年龄数据分析得到,240～338Ma峰期年龄为256Ma的年龄应代表黑龙江杂岩主体岩石的沉积年龄上限;而450～500Ma的年龄谱对应于佳木斯地体的基底变质岩年龄,显示佳木斯地体的基底变质岩曾为黑龙江杂岩的物源区;而170～210Ma,峰期年龄为183Ma的不谐和年龄应为受印支期-早侏罗世构造热事件的扰动年龄,与该区变质单矿物的Ar-Ar年龄相一致,应代表了该区陆-陆碰撞的时代.上述年龄为黑龙江杂岩的形成与演化提供了重要的地质年代学制约,即黑龙江杂岩的原岩成岩时代上限为早三叠世,佳木斯地体向西的俯冲时代主体为印支期,而陆-陆拼贴及碰撞过程主要为晚印支期并可能持续到早侏罗世.这些结果将为揭示我国东北地区构造演化的年代学格架以及三叠纪古亚洲构造域向环太平洋构造域叠加和转换的动力学背景研究提供新的基本地质事实依据. Abstract： Heilongjiang complex, along the Mudanjiang fault in the western part of the Jiamusi massif, was the high-pressure metamorphic belt due to the collision between the Jiamusi and Songnen massifs. According the tectonic-rock assemblages, metamorphism and deformation characteristics, the Heilongjiang complex are the similar to

长英质高级片麻岩中夕线石的形成与变形-变质-深熔作用的关系--以南极拉斯曼兵陵区为例-

摘要：南极拉斯曼丘陵高级长英质片麻岩的夕线片麻岩中可有两类结构和变质矿物组合均有所不同的两种域,一种含夕线石部分对应于片理组合,另一种对应无夕线石的非片理化组合.岩石的变形尤其是破裂性裂隙的率先出现对于富夕线石部分的形成是必要的.在非破裂性片麻理岩石域中,中-低压/高温条件下黑云斜长片麻岩进变质发展的结果往往是形成Grt+Qtz±Opx组合.这两种不同的变质域的组合与应变分解造成的强应变带和弱应变域相一致.而且,夕线石的形成不是简单的变质早期矿物固相反应的结果,而是反应链上的一部分.其出现是由开放体系中组分的差异迁移造成的,这种差异迁移实际上是碱土金属迁出(淋滤)的过程,与变形相伴的流体活动使得SiO_2发生强烈淋滤,残留组分中SiO_2活度大为降低,并使长英质组分和镁铁质组分分凝,主要组分大都可以单独富集(集中)、形成复杂的矿物演化和分布.这种演化还可从MgO等碱(土)金属组分的外迁程度差异来理解.随着碱(土)金属丢失程度的减小,依次出现夕线石、石榴子石、斜方辉石和堇青石,或者说,不同的变质或分异阶段形成不同的矿物(组合):变形-变质起始阶段,碱(土)金属组分迁移初期残留形成夕线石,之后为镁(铁)质组分迁移,初期残留不透明钛铁氧化物,晚期残留组分形成堇青石.石榴子石-长英质组合为体系基本封闭情况下的结晶.此外,夕线石的形成往往标志着深熔作用的开始,一旦深熔作用发展完善,夕线石呈准稳定状态或趋于消失.拉斯曼丘陵与夕线石有关的长英质岩石经历了复杂的变形、变质和流体活动变化. Abstract： In the high-grade quartzofeldspathic gneisses in the Larsemann Hills, East Antarctica, two domains of distinct mineral assemblages and textures have been discerned. One is the sillimanite-bearing assemblage aligned along the foliation, while the other

太行山南段符山高镁闪长岩的成因——拆沉陆壳物质熔融的熔体与地幔橄榄岩反应的结果-

摘要：本文对太行山南段符山高镁闪长岩进行了年代学与地球化学研究,结合其中地幔橄榄岩包体的研究,对符山高镁闪长岩的成因和中生代岩石圈地幔的性质进行了探讨.研究表明,符山闪长岩体是由一套含橄榄石角闪闪长岩-角闪闪长岩-闪长岩构成.含橄榄岩包体的寄主岩--角闪闪长岩中的锆石可划分为两种:一是代表寄主岩浆结晶的锆石:内部结构均匀、呈条带状吸收、自形-半自形晶形,具有较高的Th/U比值(1.10～4.08),其~(206)Pb/~(238)U年龄介于123～128Ma之间,12个点的加权平均值为125±1Ma,这表明岩体的形成时代为早白垩世;二是捕获或继承锆石:具有核边结构、吸收程度不均匀、呈浑圆状和自形-半自形两种,它们的Th/U比值介于0.32～2.03之间,构成了3组~(207)Pb/~(206)Pb加权平均年龄:2503±11Ma、2181±26Ma和1778±36Ma.该类岩石的SiO_2和MgO含量分别介于56.69%～59.21%和3.60%～6.33%之间;且以高:Mg~#(0.51～0.64)、富Na(Na_2O/K_2O大于1)、高Cr(93.1×10~(-6)～420×10~(-6))、Ni(35.1×10~(-6)～137×10~(-6))为特征.该类岩石强烈富集轻稀土元素和大离子亲石元素、明显亏损高场强元素,(87Sr/86Sr)I、ε_(Nd)(t)值和(~(206)Pb/~(204)Pb)I分别变化于0.70581～0.70641、-8.30～-16.56和17.052～17.512之间.综合上述特征,同时结合地幔橄榄岩包体的特征和古元古代捕获锆石的大量存在,认为符山高镁闪长岩的原始岩浆起源于拆沉陆壳物质的部分熔融,其后经历了与地幔橄榄岩的反应过程. Abstract： This paper reports chronological and geochemical data of the Fushan high-Mg~# diorites from the southern Taihang Mts. And discusses its petrogenesis and nature of the Mesozoic lithospheric mantle beneath the central North China Craton together with the mantle peridotite xenoliths entrained by them. The Fushan dioritic intrusion is composed mainly of olivine-bearing hornblende-diorite, hornblende-diorite and diorite. Based on their shape and s

华北克拉通东北缘岩石圈深部物质组成的不均一性:来自吉林南部中生代火山岩元素及Sr-Nd同位素地球化学的证据-

摘要：本文报导了吉林南部果松组和三棵榆树组火山岩的全岩K-Ar和角闪石~(40)Ar/~(39)Ar定年结果和岩石地球化学资料,并讨论了吉林南部早白垩世火山岩岩浆源区性质以及空间变异.定年结果显示,果松组和三棵榆树组火山岩的形成时代分别为130.2±0.3Ma和118.3±1.9Ma.果松组火山岩主要由玄武岩-玄武质粗面安山岩-粗面安山岩-英安岩组成;它们的SiO_2含量介于46%～64%,Mg~#介于31～50之间,Al_2O_3含量介于14.9%～18.9%之间,全碱含量(Na_2O+K_2O)介于4.61%～9.23%之间,属于亚碱性系列,具钙碱性演化趋势;并以富集大离子亲石元素(LILEs)和轻稀土元素(LREEs),亏损重稀土元素(HREEs)和Nb、Ta、Ti等高场强元素(HFSEs)为特征;(~(87)Sr/~(88)Sr)_i值和ε_(Nd)(t)值分别介于0.7065～0.7077和-2.67～-19.71之间.果松组火山岩的成分具有较好的空间变异趋势,由东向西,火山岩的基性程度增高,东部果松组火山岩具有较高的(~(87)Sr/~(86)Sr)_i值,而西部具有较低的ε_(Nd)(t)值.三棵榆树组火山岩由粗面安山岩和粗面英安岩组成;三棵榆树组火山岩的SiO_2含量介于55.5%～65.8%之间,Mg~#介于42～50,Al_2O_3含量介于15.0%～15.7%,全碱含量偏高(Na_2O+K_2O=6.93%～9.24%),主体属于亚碱性系列,具钙碱性系列的演化趋势;并以较高的Th/U(5.36～5.82)、Ba/Nb(50.2～120.0)、(La/Yb)N(32.9～47.9)和Sr/Y(50.0～72.4)比值为特征;它们的(~(87)Sr/~(86)Sr)_i值和ε_(Nd)(t)值分别变化于0.7056～0.7057和-8.99～-19.71之间.上述特征揭示,果松组火山岩(130Ma)的形成主要与古太平洋板块的俯冲作用有关,岩浆来源于受流体/熔体交代的地幔楔,东西部受到不同程度陆壳物质的混染.与果松组火山岩相比,三棵榆树组火山岩(118Ma)形成于俯冲背景下的相对引张环境,岩浆来源于受交代的岩石圈地幔,但受到深部陆壳物质的混染. Abstract： This paper reports the whole-rock K-Ar and amphibole ~(40)Ar/~(39)Ar dating results

冀东晚古生代东湾子岩体的岩石成因研究-

摘要：冀东晚古生代东湾子岩体由角闪石岩、少量辉石岩和辉长岩组成.典型的堆晶结构、全岩和镁铁质矿物(透辉石、角闪石)的上凸型稀土分布模式、相容元素含量低且变化范围大(如:角闪石岩中V=296×10~(-6)～673×10~(-6))的特征表明了岩体的堆晶成因.计算得到的与辉石岩中的透辉石相平衡的熔体具有很高的稀土含量,轻重稀土分馏较为明显,富集大离子亲石元素(如:Sr,Ba,K),亏损高场强元素(如:Nh,Zr,Ti),具有典型的弧岩浆特征.透辉石和角闪石的矿物成分也具有弧岩浆的特征.高钙透辉石、大量的角闪石与黑云母的存在说明母岩浆富水.透辉石在高P_(H2O)的状态下与熔体反应,生成角闪石的结构特征也证明了这一点.结合岩体的球化学特征,认为岩浆来源于富集的含有角闪石的尖晶石橄榄岩的部分熔融,母岩浆具有富水的特征(>3%).考虑到岩体形成时代(～300Ma;Zhao et al.,2007)和地质背景,认为东湾子岩体与位于华北北缘的其它晚石炭-早二叠世的岩体形成于同一构造背景下,都是晚古生代时期古亚洲洋向华北板块之下俯冲的产物. Abstract： The Late Paleozoic Dongwanzi plnton is made up of hornblendite, pyroxenite and gabbro. Cumulate origin of these rocks is suggested by the cumulative textures, the convex-upward REE patterns of whole rock and mafic minerals (diopside and hornblende), and the low and large variation of compatible elements such as V in hornblendites. Calculated REE patterns of the parental magma in equilibrium with the pyroxenite show strong fractionation between LREE and HREE. The enrichment in LILE (e. g. Sr, Ba, K) and depletion in HFSE (e. g. Nb, Ta, Ti) , along with the compositions of diopside and hornblende, suggest their arc magmatic affinity. High Ca-diopside, magmatic hornblende and the reactions between diopside and melt to form amphibole all can be attributed to the high content of water in the parental magma. It seems that the parent

大兴安岭地区德尔布干断裂带北段构造年代学研究-

摘要：德尔布干断裂带是大兴安岭隆起西侧NE向的重要断裂带,处在海拉尔-拉布达林-根河盆地西缘,是著名德尔布干成矿区东南边界断裂带.为了确定德尔布干断裂带运动性质、活动时间,深入探讨该断裂带与中生代海拉尔-拉布达林-根河盆地及大兴安岭盆山格局、认识德尔布干断裂带多金属矿床成因等问题,本文应用锆石SHRIMP和云母~(40)Ar/~(39)Ar定年技术,分别对断裂带内的细粒黑云母花岗岩侵入体、韧性变形的花岗闪长质片麻岩、白云母石英片岩,进行了同位素年代学研究.其中花岗闪长质片麻岩岩浆型锆石SHRIMP谐和年龄300.6±9.3Ma,为花岗闪长质片麻岩海西期的侵位年龄;而花岗闪长质片麻岩中黑云母~(40)Ar/~(39)Ar坪年龄是130.9±1.4Ma,白云母石英片岩的白云母~(40)Ar/~(39)Ar坪年龄是115.6±1.6Ma,代表早白垩世伸展构造变形年龄;细粒黑云母花岗岩侵入体岩浆型锆石SHRIMP谐和年龄130.1±1.4Ma,为同伸展构造变形侵位的岩浆事件.上述地质年代说明德尔布干断裂带是早白垩世(110～130Ma)该区最年轻的重大伸展构造变形产物.控制NE向大兴安岭隆起和中生代海拉尔-拉布达林-根河等火山沉积盆地的发育格局、以及中生代以来的地壳演化与成矿类型. Abstract： Derbugan fault zone, a NE tending fault zone in the West of the Great Xing' an Range uplift and along the western margin of the Hailar-Labudalin-Genhe basins, is the famous zone which is the NS boundary fault zone of the Derbugan metallogenic belt. In order to understanding the character for the activity and timing of this fault, and its relations to the Hailar-Labudalin-Genhe basins, and polymetal ore deposit along this fault, we show the SHRIMP zircon and mica ~(40)Ar/~(39)Ar dating for the granule-biotite granitic vein, granodioritic gneiss with ductile deformation and mica-quartz schist in this fault zone. SHRIMP zircon U-Pb dating of the granodioritic gneiss yield concordant ag