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Transformation of olivine to diopside via interaction with carbonatite melts

Science China Earth Sciences 2023年第10期66卷 2332-2339页

作者： Jing WANG Ben-Xun SU sanjeewa p.k.malaviarachchi patrick Asamoah SAkYI prasanna L.DHARMApRIYA key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China University of Chinese Academy of Sciences Beijing100049China Department of Geology Faculty of ScienceUniversity of PeradeniyaPeradeniya20400Sri Lanka Department of Earth Science School of Physical and Mathematical SciencesUniversity of GhanaLegon-AccraGhana

Numerous empirical and experimental studies have documented the consumption of orthopyroxene and production of clinopyroxene in mantle peridotite during carbonatite metasomatism,whereas little attention has been paid to whether and how olivine is compositionally modified through the same process of carbonatite ***,we present the discovery of well-preserved reaction features in olivine from typical calciocarbonatites from Sri *** olivine grains experienced serpentinization along the cracks and in their rims and are generally surrounded outwardly by serpentine,tremolite and diopside *** inner serpentine zone is dominated by serpentine with tiny magnetite,whereas the mantle tremolite zone is characterized by euhedral tremolite and intergrowth of dolomite with small amounts of serpentine relics and *** outer diopside zone shows spongy texture and commonly encloses olivine,serpentine,tremolite and dolomite,which are also observed in interstitial diopside grains in the *** profile analyses reveal that these olivine grains display decreasing FeO and increasing MgO contents and thus elevating Fo values from their cores to the reaction rims,while the serpentine inherits compositions from the *** mapping images demonstrate outward diffusion of Si and Mg in the serpentine zones and contribution of Ca from carbonatite melts during tremolite *** interaction with carbonatite melts produced Si-and Mg-poor and Ca-rich diopside relative to the reactant *** observations suggest that the interaction with carbonatite melts first transformed olivine to diopside through serpentinization,followed by *** diopside formed through olivine-carbonatite melt interaction is anomalously depleted in Na and Al and enriched in Ca,which are distinct from those generated in interactions between orthopyroxene and both carbonatite and silicate *** implies that for the first time some w

关键词： Olivine Carbonatite Diopside Tremolite Melt-mineral interaction

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New constraints on the p-T path of HT/UHT metapelites from the Highland Complex of Sri Lanka

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Geoscience Frontiers 2017年第6期8卷 1405-1430页

作者： p.L.Dharmapriya sanjeewa p.k.malaviarachchi L.M.kriegsman Andrea Galli k.Sajeev Chengli Zhang postgraduate Institute of Science University of Peradeniya20400Sri Lanka Department of Geology Faculty of ScienceUniversity of Peradeniya20400Sri Lanka Naturalis Biodiversity Center Darwinweg 2NL-2333 CR LeidenThe Netherlands Department of Earth Sciences Utrecht UniversityBudapestlaan 4NL-3584 CD UtrechtThe Netherlands Department of Earth Sciences ETH ZurichSonnegstrasse 5CH-8092 ZurichSwitzerland Centre for Earth Sciences Indian Institute of ScienceBangalore 560012India key Laboratory of Continental Dynamics of Northwest University Department of GeologyNorthwest UniversityXi’an 710069China

We report here rare evidence for the early prograde p-Tevolution of garnet-sillimanite-graphite gneiss(khondalite)from the central Highland Complex,Sri *** types of garnet porphyroblasts(Grt_1,Grt_2,Grt_3 and Grt_4)are observed in the rock with specific types of inclusion *** Grt_3 shows evidence for non-coaxial *** the information shows a sequence of main inclusion phases,from old to young:oriented quartz inclusions at core,staurolite and prismatic sillimanite at mantle,kyanite and kyanite pseudomorph,and biotite at rim in Grt_1;fibrolitic sillimanite pseudomorphing kyanite±corundum,kyanite,and spinel+sillimanite after garnet+corundum in Grt_2;biotite,sillimanite,quartz±spinel in Grt_3;and ilmenite,rulite,quartz and sillimanite in Grt_*** pre-melting,original rock composition was calculated through stepwise re-integration of melt into the residual,XRF based composition,allowing the early prograde metamorphic evolution to be deduced from petrographical observations and *** earliest recognizable stage occurred in the sillimanite field at around 575℃ at 4.5 *** collision associated with Gondwana amalgamation led to crustal thickening along a p-T trajectory with an average dp/dT of ~30 bar/℃ in the kyanite field,up to ~660℃ at 6.5 kbar,before crossing the wet-solidus at around 675 ℃ at 7.5 *** highest pressure occurred at p > 10 kbar and T around 780℃ before prograde decompression associated with further *** 825℃ and 10.5 kbar,the rock re-entered into the sillimanite *** temperature peaked at 900℃ at ca.9-9.5 *** near-isobaric cooling led to the growth of Grt_4 and rutile at T ~880℃.Local pyrophyllite rims around sillimanite suggest a late stage of rehydration at Tprobably occurred after uplift to upper crustal levels.U-pb dating of zircons by LAICpMS of the khondalite yielded two concordant ^(206)pb/^(238)U age groups with mean values of 542±2 Ma(MSWD=0.24,Th/U=0.01-0.

关键词： prograde evolution Melt re-integration Highland Complex Sri Lanka UHT granulites

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Distinct metamorphic evolution of alternating silica-saturated and silica-deficient microdomains within garnet in ultrahigh-temperature granulites: An example from Sri Lanka

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Geoscience Frontiers 2017年第5期8卷 1115-1133页

作者： p.L.Dharmapriya sanjeewa p.k.malaviarachchi Leo M.kriegsman k.Sajeev Andrea Galli Y.Osanai N.D.Subasinghe C.B.Dissanayake postgraduate Institute of Science University of Peradeniya 20400 Sri Lanka Department of Geology Faculty of Science University of Peradeniya 20400 Sri Lanka Department of Geology Naturalis Biodiversity Center Darwinweg 2 2333 CR Leiden The Netherlands Department of Earth Sciences University of Utrecht NL-3584 CD Utrecht The Netherlands Center for Earth Sciences Indian Institute of Science Bangalore 560012 India Department of Earth Sciences ETH Zurich Sonnegstrasse 5 CH-8092 Zurich Switzerland Division of Earth Sciences Department of Environmental Changes Faculty of Social and Cultural Studies Kyushu University 744 Motooka Fukuoka 819-0395 Japan National Institute of Fundamental Studies Hantana Road Kandy Sri Lanka

Here we report the occurrence of garnet porphyroblasts that have overgrown alternating silica-saturated and silica deficient microdomains via different mineral reactions. The samples were collected from ultrahigh-temperature(UHT) metapelites in the Highland Complex, Sri Lanka. In some of the metapelites, garnet crystals have cores formed via a dehydration reaction, which had taken place at silicasaturated microdomains and mantle to rim areas formed via a dehydration reaction at silica-deficient microdomains. In contrast, some other garnets in the same rock cores had formed via a dehydration reaction which occurred at silica-deficient microdomains while mantle to rim areas formed via a dehydration reaction at silica-saturated microdomains. Based on the textural observations, we conclude that the studied garnets have grown across different effective bulk compositional microdomains during the prograde evolution. These microdomains could represent heterogeneous compositional layers(paleobedding/laminations) in the precursor sediments or differentiated crenulation cleavages that existed during prograde metamorphism. UHT metamorphism associated with strong ductile deformation, metamorphic differentiation and crystallization of locally produced melt may have obliterated the evidence for such microdomains in the matrix. The lack of significant compositional zoning in garnet probably due to self-diffusion during UHT metamorphism had left mineral inclusions as the sole evidence for earlier microdomains with contrasting chemistry.

关键词： UHT Metapelites Garnet Microdomains Highland Complex Sri Lanka

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Geochemistry and geochronology of acidic rocks in the Beishan region,NW China:petrogenesis and tectonic implications

Geochemistry and geochronology of acidic rocks in the Beisha...

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中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： patrick Asamoah Sakyi sanjeewa p.k.malaviarachchi Department ofEarth Science University of GhanaP.O.Box LG 58Legon-AccraGhana Research School of Earth Sciences The Australian National UniversityBuilding 61Mills Road ActonCanberraAct 0200Australia

The dacites and granites from the Beishan region are characterized by highly-fractionated REE,enrichments in LILE,and depletion in Nb,Ta and *** dacites contain zircons with ages ranging from 265 to 748 *** features suggest that they were probably derived from the older lower continental crust and were later on subjected to significant crustal *** rhyolites,diorites and diabases,all of which share similar geochemical features such as trace element patterns,zircon U-pb ages of～280 Ma, positiveε(f) andε(f),high initial(Sr/Sr)i andδO‰values,were most likely derived from the juvenile crustal sources and subsequently experienced fractional crystallization and crustal contamination. These acidic igneous rocks(except dacites and granites) and coeval mafic-ultramafic intrusions form a bimodal igneous *** implies that the Beishan region was a Late paleozoic rift probably developed in association with the early permian mantle plume activity in the Tarim Basin.

关键词： Beishan Central Asian Orogenic Belt Dacite Magmatism Rhyolite Zircon U-pb-Hf-O isotopes

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U-pb ages and Hf-O isotopes of zircons from Late paleozoic mafic-ultramafic units in the southern Central Asian Orogenic Belt:Tectonic implications and evidence for an Early-permian mantle plume

U-Pb ages and Hf-O isotopes of zircons from Late Paleozoic m...

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中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： patrick Asamoah Sakyi sanjeewa p.k.malaviarachchi Department of Earth Science University of GhanaP.O.Box LG 58Legon-AccraGhana Research School of Earth Sciences The Australian National UniversityBuilding 61Mills Road ActonCanberraAct 0200Australia

U-pb age and Hf-O isotope data of zircons from the mafic-ultramafic complexes and their related rhyolites and granites in the Eastern Tianshan and Beishan regions were obtained by SIMS and *** Hf-O isotopic composition and Hf model age of the zircons are closely related to their tectonic setting and formation *** zircons from the mafic-ultramafic complexes in the Bogeda-Haerlike and Jueluotage belts have higherε(t) (+ 8-+ 17) and lowerδO(+ 4‰- + 6‰),whereas most of the zircons in the gabbros,granites and rhyolite from the Middle Tianshan Massif and Beishan Rift display lowerε(t)(0- + 8) and higherδO(+ 5‰- + 8‰). The positiveε(t) and relatively lowerδO values suggest that these mafic-ultramafic complexes were derived from depleted mantle which was subjected to subduction-related modification *** Hf isotopic composition of zircons in the granites has revealed that the growth of juvenile crust was also very significant in the southern margin of the Central Asian Orogenic Belt during the *** Hf model ages of the analyzed zircons,together with the regional geology suggest that the Beishan area had a northward subduction,possibly from ca.900 Ma to ca.400 Ma,whereas the Eastern Tianshan had a south-directed subduction most likely from ca. 600 Ma to ca.310 ***,zircons with ca.280 Ma U-pb ages display wider and more scatteredε(t) andδO variations than the relatively older and younger ones,which further support the Early permian mantle plume model.

关键词： Central Asian Orogenic Belt Mafic-ultramafic complex Mantle plume U-pb-Hf-O isotope Zircon

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Geochronologic-petrochemical studies of the Hongshishan mafic-ultramaflc intrusion,Beishan area,Xinjiang(NW China):petrogenesis and tectonic implications

Geochronologic-petrochemical studies of the Hongshishan mafi...

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中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： Benxun Su kezhang Qin patrick Asamoah Sakyi Dongmei Tang pingping Liu sanjeewa p.k.malaviarachchi Qinghua Xiao He Sun key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of Sciences State key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences Department of Earth Science University of GhanaP.O.Box LG 58Legon-AccraGhana Research School of Earth Sciences The Australian National UniversityBuilding 61Mills Road ActonCanberraACT 0200Australia

The Hongshishan mafic-ultramafic intrusion(SIMS zircon U-pb age 286.4±2.8 Ma) consists of dunite,clinopyroxene peridotite,troctolite,and *** elements display systematic *** elements have identical distribution patterns,including flat rare-earth element(REE) patterns with positive Eu anomalies and enrichments in large ion hthophile elements(LILE) but depletions in Nb and Ta,indicating fractional crystallization as a key factor in magmatic evolution. petrologic and geochemical variations in drill core samples demonstrate that minor assimilation and progressive magma mjectioiis were closely associated with Ni-Cu *** balance estimates and Sr-Nd isotopes reveal that the Hongshishan parental magmas were high-Mg and low-Ti tholeiitic basalts and were derived from a lithospheric mantle source that had been modified by subducted slab metasomatism before partial melting. Southward subduction of the palaeo-Tianshan-Junggar Ocean is further constrained by a compilation of inferred subduction-induced modifications of mantle sources in mafic-ultramafic intrusions distributed in the eastern Tianshan-Beishan *** the regional positiveεNd(t) granites,high-Mg and low-Ti basaltic magmas(mafic-ultramafic intrusions),and slightly later high-Ti basalts in NW China suggests that their petrogenesis could be attributed to permian mantle plume activities.

关键词： Beishau eastern Tianshan fractional crystallization mafic-ultramafic intrusions mantle plume

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The metasedimentary rocks from the eastern margin of the Tarim Craton:petrology,geochemistry,zircon U-pb dating,Hf isotopes and tectonic implications

The metasedimentary rocks from the eastern margin of the Tar...

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中国科学院地质与地球物理研究所2013年度（第13届）学术年会

作者： Zhong-Mei Wang Chun-Ming Han Ben-Xun Su patrick Asamoah Sakyi sanjeewa p.k.malaviarachchi Song-Jian Ao Luo-Juan Wang State key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences University of Chinese Academy of Sciences Department of Earth Science University of Ghana Department of Geology Faculty of ScienceUniversity of Peradeniya State key Laboratory of Lithosphefic Evolution Institute of Geology and GeophysicsChinese Academy of Sciences

The Dunhuang Block,located in the eastern Tarim Craton,widely exposes precambrian TTG gneisses and metamorphosed supracrustal rocks.A suite of metasedimentary rocks of the Dunhuang Group in the Hongliuxia area on the eastern margin of the Tarim Craton are characterized by moderate contents of quartz,plagiodase,and biotite,with minor amounts of garnet or kyanite,most of which have experienced strong deformation,resulting in welldeveloped amphibolite-facies *** examined samples are characterized by moderate FeO+MgO and TiO contents,and AlO/SiO and kO/NaO ratios with low Chemical Index of Alteration(CIA)and high Index of Compositional Variability(ICV)values,suggesting that the protolith sediments originated from continental island arc *** U-pb ages of magmatic-type detrital zircons from the Hongliuxia metasedimentary rocks range between 2476 Ma and 1950 Ma,with a peak at 2417 *** zircons of metamorphic origin yielded an age peak at 1832 Ma,which may represent a tectono-thermal event in the paleoproterozoic,Considering that the main age populations of the analyzed samples are consistent with the tectono-thermal events in the Tarim Craton during the early paleoproterozoic,we propose that the Tarim Craton was possibly the major source for the protolith sediments of the metasedimentary rocks in the Hongliuxia area,Zircon Hf isotopic compositions (ε(t)=-5.8 to+2.9)suggest voluminous addition of juvenile materials to the crust and minor reworking of old materials in the eastern Tarim Craton during the Mesoarchean(T=2.8-2.9 Ga).The metasedimentary rocks of the Hongliuxia area provide dear constraints to the evolution of the Tarim Craton,A possible tectonic model is that multiple thermal events(～2.4 Ga,2.2 Ga,2.0 Ga and 1.8 Ga)occurred in the study area,and the time period of Mesoarchean was important for crustal growth in the eastern Tarim Craton,whereas the～1.83 Ga metamorphism might represent a thermal event assodated with the Tarim Craton wit

关键词： Tarim Craton Metasedimentary rocks provenance Zircon U-pb dating Hfisotopes

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Occurrence of an Alaskan-type complex in the Middle Tianshan Massif,Central Asian Orogenic Belt:inferences from petrological and mineralogical studies

Occurrence of an Alaskan-type complex in the Middle Tianshan...

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中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： Ben-Xun Su ke-Zhang Qin patrick Asamoah Sakyi sanjeewa p.k.malaviarachchi ping-ping Liu Dong-Mei Tang Qing-Hua Xiao He Sun Yu-Guang Ma Qian Mao key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of Sciences Graduate University of Chinese Academy of Sciences Department of Earth Science University of GhanaP.O.Box LG 58Legon-AccraGhana Research School of Earth Sciences The Australian National UniversityCanberraACT 0200Australia State key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences

The Xiadong mafic-ultramafic complex hes in the central part of the Middle Tianshan Massif(MTM),along the southern margin of the Central Asian Orogenic Belt(CAOB).This complex is composed of dunite,hornblende(Hbl) clinopyroxenite, hornblendite,and Hbl *** rocks are characterized by adcumulated textures and variable *** is an extremely rare mineral in all rock units and plagioclase is absent in dunite and Hbl ***,Fe-chromite, and Cr-magnetite are common *** have forsterite(Fo) contents ranging from 92.3 to *** are Ca-rich,Ti-poor diopsides,and mostly altered to tremolites or *** display low TiO and AlO contents and high Cr# and Fe(Fe + Mg) *** and secondary Hbls show wide compositional *** petrological and mineralogical features as well as mineral chemistry are comparable to typical Alaskan-type complexes worldwide, which are widely considered to have formed above subduction *** chemistry of clinopyroxene and chromite supports an arc plate-tectonic origin for the Xiadong *** confirmation as an Alaskan-type complex implies that the MTM,with precambrian basement,was probably a continental arc during oceanic plate underflow and further supports the hypothesis of southward subduction of the palaeozoic Junggar Ocean.

关键词： Alaskan-type mafic-ultramafic complex Central Asian Orogenic Belt mafic-ultramafic complex Middle Tianshan Massif continental arc

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Formation of Melt pocket in Mantle peridotite Xenolith from Western Qinling, Central China: partial Melting and Metasomatism

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Journal of Earth Science 2010年第5期21卷 641-668页

作者：苏本勋张宏福 patrick Asamoah Sakyi 秦克章刘平平英基丰汤艳杰 sanjeewa p.k.malaviarachchi 肖燕赵新苗毛骞马玉光 key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences State key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences Department of Earth Science University of Ghana Legon-Accra Ghana Research School of Earth Sciences The Australian National University Canberra Act 0200 Australia

Two types of melt pockets, closed melt pocket （CMp） and open melt pocket （OMp）, are recognized from the peridotite xenoliths entrained in the Cenozoic kamafugites in western Qinling （秦岭）, Central China. The Haoti （好梯） CMps have a mineral assemblage of olivine＋ clinopyroxene＋amphibole＋k- feldspar, whereas the Baiguan （白关） CMps are composed of olivine＋clinopyroxene＋Umenite＋carbonate. The components of the OMps are more complicated. In the Haoti OMps, there are olivine, ciinopyroxene, glass, low modal abundances of amphibole, k-feldspar （kfs）, Umenite, sulfide, chlorite, perovskite, chromite and phlogopite. The Baiguan OMps contain olivine, clinopyroxene, glass, chlorite and chromite. Compositionally, ofivines in the CMps and OMps are both apparently depleted in Ni, and those in the OMps are also depleted in Fe and Mg, and enriched in Ca compared to the primary ones. Ciinopyroxenes display large and systematical compositional variations between the CMps and OMps, particularly in Al, Cr, Na, Ca and Ti. Glasses are generally depleted in Si compared to the worldwide glasses in melt pockets, although they still have large variations. Amphiboles and k-feldspars have relatively restricted compositional variations. The petrographical observations and mineral chemistry suggest that the Haoti and Baiguan CMps were generated by the in-sitn decompression melting of orthopyroxenes, olivines and clinopyroxenes, and by the addition of minor external k-rich and Ca-rich melt/fluids. The OMps formed during the latest metasomatic event in the lithospheric mantle beneath the western Qinling.

关键词： mantle metasomatism melt pocket partial melting peridotite xenolith western Qinling.

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斯里兰卡地质演化研究的进展与评述:岩石组合、变质演化及其与冈瓦纳大陆的关系

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岩石学报 2021年第5期37卷 1287-1320页

作者：赵磊张艳斌 malaviarachchi sanjeewa prabhath kumara DHARMApRIYA prasanna Lakshitha 翟明国中国科学院地质与地球物理研究所岩石圈演化国家重点实验室北京100029 斯里兰卡佩拉德尼亚大学地质系康堤20400

地球表生环境的演变及生命演化过程,与地球构造过程密切相关,新元古代-寒武纪时期的冈瓦纳大陆汇聚过程见证了一系列剧变。东非造山带(ca.650~620Ma)和kuunga造山带(ca.600~500Ma)是冈瓦纳大陆块体汇聚过程中形成的两条主要造山带,二者... 详细信息

地球表生环境的演变及生命演化过程,与地球构造过程密切相关,新元古代-寒武纪时期的冈瓦纳大陆汇聚过程见证了一系列剧变。东非造山带(ca.650~620Ma)和kuunga造山带(ca.600~500Ma)是冈瓦纳大陆块体汇聚过程中形成的两条主要造山带,二者在斯里兰卡所在的区域十字交叉。因此斯里兰卡地质演化历史的准确梳理,对理解新元古代时期全球构造过程的重要意义不言而喻。斯里兰卡的四个前寒武纪地质体(Wanni、kadugannawa、Highland和Vijayan杂岩地体)中,中部的Highland杂岩地体最古老(ca.2000~1800Ma)、变质程度最高(普遍麻粒岩相,局部为超高温麻粒岩相),其余三个地质体主要岩石的形成时代为中元古代晚期-新元古代(ca.1100~700Ma),岩石记录的变质级别略低于Highland地体,为角闪岩相-麻粒岩相。现有研究表明斯里兰卡几个地质体在新元古代-寒武纪时期(ca.610~500Ma)的变质作用记录最为显著,并伴随有广泛的陆壳重熔再造。该构造热事件晚于东非造山带的变质时代(ca.650~620Ma),与kuunga造山带活动时间(ca.600~500Ma)吻合度较高,这与前人提出的莫桑比克缝合带(东非造山带)穿过斯里兰卡的认识相矛盾。斯里兰卡的高级变质作用究竟是单次造山作用的结果,还是代表了两期造山事件的叠加效应,目前尚无定论。高温-超高温变质作用是斯里兰卡前寒武纪基底岩系的显著特征,其中超高温麻粒岩具有假蓝宝石+石英、紫苏辉石(Al2O3含量可达~13%)+夕线石、尖晶石+石英等的矿物组合,不同研究者给出超高温峰期变质温度在950~1150℃的范围内,峰期变质压力在10~16kbar的范围内,多显示顺时针演化p-T轨迹。斯里兰卡中东部地区的基性麻粒岩,发育由斜方辉石+斜长石、角闪石+斜长石或单斜辉石+斜长石组成的环绕石榴石的蠕虫状后成合晶结构,指示近等温降压的p-T演化样式,以及峰期变质作用之后地体相对快速抬升的演化过程。紫苏花岗岩在斯里兰卡不同地体中都很常见,与所有的高级变质岩(如泥质、基性麻粒岩和钙硅酸盐岩等)密切伴生,是研究斯里兰卡地质演化不可忽视的岩石类型。紫苏花岗岩的原岩成因较为复杂,其最古老部分的形成时代可能为太古宙或古元古代(~1850Ma),但是没有很好的年代学限定。部分紫苏花岗岩原岩时代为ca.1100~750Ma,具有钙碱性弧岩浆的地球化学特征,并记录ca.580~500Ma的变质作用,还有一部分紫苏花岗岩时代与区域麻粒岩相变质作用的峰期时代相当,为ca.580~550Ma。在一些地区的角闪片麻岩中,还可以观察到补丁状分布的初始紫苏花岗岩,其形成时代多被认为晚于峰期麻粒岩相变质时代。斯里兰卡四个前寒武纪地质体在岩石组合、变质级别、地质年代学格架等方面的差异被普遍认同,暗示这些地质体具有不同的演化历史。但是斯里兰卡不同地质体的汇聚过程是否对应于莫桑比克洋的闭合,以及kuunga造山带如何改造斯里兰卡的基底岩石,目前并不清楚。本文综述了前人发表的研究结果,主要从斯里兰卡不同地质体岩石组合、高温-超高温变质作用(Highland地体)、变质地质年代学及其对冈瓦纳大陆重建的启示等几个方面,对斯里兰卡地质演化研究进行归纳和小结。在此基础上提出,在斯里兰卡基底构造框架、新元古代晚期-寒武纪高温-超高温变质作用、紫苏花岗岩成因、地质演化的年代学格架、斯里兰卡在冈瓦纳大陆重建中的位置和作用、下地壳热状态和热源机制等诸多方面,还存在问题和争议,是值得未来开展深入研究的方向。

关键词：斯里兰卡前寒武纪地体 UHT变质作用变质年代学冈瓦纳大陆

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