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1.
Zircon LA-ICP-MS U-Pb dating reveals that the Baimashan Pluton is composed mainly of late Indosinian (204.5±2.8 Ma-209.2±3.8 Ma) biotite granodiorites/monzonitic granites (LIGs) and early Yanshanian (176.7±1.7 Ma) two-micas monzonitic granites (EYGs), and the coeval (203.2±4.5 Ma-205.1±3.9 Ma) mafic microgranular enclaves (MMEs) are generally found in the former. In addition, the ages of cores within zircons from LIGs and MMEs ranging from 221.4±4.0 Ma to 226.5±4.1Ma provide evidence of multistage magma intrusion during Indosinian in the study area. Measured 3010±20.6 Ma of inherited zircon age suggests that there may be recycling Archaean curstal material in existence in this area. LIGs and EYGs share some similar geochemical features: subalkaline and peraluminous granites, enrichment of Th, U, K, Ta, Zr, Hf and LREE but depletion of Ba, Nb, P, Ti and Eu, low εNd(t) values but high (87Sr/86Sr)i ratios, and old T2DM (ca. 1.9-2.0 Ga). The behaviors of incompatible elements and REE are mainly dominated by fractional crystallization of plagioclase, K-feldspar, ilmenite and apatite, but that of Sr isotope mainly controlled by EC-AFC. They are crust-sourced and derived from partial melting of paleo-Proterozoic metagreywackes and related to biotite dehydration melting. LIGs are formed in post-collisional tectonic setting as crustal local extension and thinning during late Indosinian. But EYGs may be evolved products of congeneric granitic magma with LIGs formed in late Indoinian, which were emplaced again when crust underwent extensive thinning and extension in post-orogenic tectonic setting during Yanshanian in SC after undergoing EC-AFC. MMEs should be cognate enclaves and derived from liquid immiscibility of host magma.  相似文献   

2.
The strongly peraluminous granites (SPGs) of Eastern Nanling Range (ENR) are a characteristic of all bearing highly aluminous minerals, such as muscovite±AI-rich biotite±tourmaline±garnet, and lack of cordierite. In respect of petrography, geochemistry, Nd isotope, and single grain zircon U-Pb dating, the representative granite bodies of them are studied. The research shows that these granites were emplaced in two stages, namely 228-225 Ma BP and J2-3 159-156 Ma BP, belonging to Indosinian and early Yanshanian periods, respectively, and they have low εNd(t) values (-10.6--11.1), high A/CNK, Rb/Sr ratios and tDM values (1887-1817 Ma), and REE's tetrad effect (TE1,3=1.13-1.34). In comparison with related geology, petrology and chronology of granites in adjacent regions, it is suggested that Indosinian SPGs of ENR formed in the circumstance of post-collisional extension 20 Ma after the major collision of Indosinian Movement (258-243 Ma BP) in Indo-China Peninsula, and early Yanshanian SPGs formed in the  相似文献   

3.
Early Yanshanian magmatic suites predominate absolutely in the Nanling granite belt. They consist mainly of monzogranite and K-feldspar granite. There occur associations of early Yanshanian A-type granitoids (176 Ma-178 Ma) and bimodal volcanic rocks (158 Ma-179 Ma) in southern Jiangxi and southwestern Fujian in the eastern sector of the granite belt and early Yanshanian basalts (177 Ma-178 Ma) in southern Hunan in the central sector of the belt. Both the acid end-member rhyolite in the bimodal volcanic rock association and A-type granitoids in southern Jiangxi have the geochemical characteristics of intraplate granitic rocks and the basic end-member basalt of the association is intraplate tholeiite, while the basaltic rocks in southern Hunan include not only intraplate tholeiite but also intraplate alkali basalt. Therefore the early Yanshanian magmatic suites in the Nanling region are undoubtedly typical post-orogenic rock associations. Post-orogenic suites mark the end of a post-collision or late orogenic event and the initiation of Pangaea break-up, indicating that a new orogenic Wilson cycle is about to start. Therefore it may be considered that the early Yanshanian geodynamic settings in the Nanling region should be related to post-orogenic continental break-up after the Indosinian orogeny and the break-up did not begin in the Cretaceous.  相似文献   

4.
Early Yanshanian magmatic suites predominate absolutely in the Nanling granite belt.They consist mainly of monzogranite and K-feldspar granite.There occur associations of early Yanshanian A-type granitoids(176 Ma-178 Ma) and bimodal volcanic rocks(158 Ma-179 Ma) in southern Jiangxi and southwestern Fujian in the eastern sector of the granite belt and early Yanshanian basalts(177 Ma-178 Ma) in southern Hunan in the central sector of the belt.Both the acid end-member rhyolite in the bimodal volcanic rock association and A-type granitoids in southern Jiangxi have the geochemical characteristics of intraplate granitic rocks and the basic end-member basalt of the association is intraplate tholeiite,while the basaltic rocks in southern Hunan include not only intraplate tholeiite but also intraplate alkali basalt.Therefore the early Yanshanian magmatic suites in the Nanling region are undoubtedly typical post-orogenic rock associations.Post-orogenic suites mark the end of a post-collision or late orogenic event and the initiation of Pangaea break-up,indicating that a new orogenic Wilson cycle is about to start.Therefore it may be considered that the early Yanshanian geodynamic settings in the Nanling region should be related to post-orogenic continental break-up after the Indosinian orogeny and the break-up did not begin in the Cretaceous.  相似文献   

5.
The large-scale Huangshaping Pb-Zn-W-Mo polymetallic deposit is located in the central Nanling min- eralization zone, South China. Six molybdenite samples from the Huangshaping deposit were selected for Re-Os isotope measurement in order to define the mineralization age of the deposit. It yields a Re-Os isochron age of 154.8±1.9 Ma (2σ ), which is in accordance with the Re-Os model ages of 150.9― 156.9 Ma. This age is about 7 Ma younger than their host granite porphyry, which was dated as 161.6±1.1 Ma by zircon U-Pb method using LA-ICPMS. All these ages demonstrate that the Huang- shaping granite and related Pb-Zn-W-Mo deposit occurred in the middle Yanshanian period, when many other granitoid and related ore deposits emplaced and formed, e.g. the Qitianling granite and Furong tin deposit, the Qianlishan granite and giant Shizhuyuan W-Sn-Mo-Bi deposit and Jinchuantang Sn-Bi deposit in the nearby area. They constitute the main part of the magmatic-metallogenic belt of southern Hunan, and represent the large-scale metallogeny in middle Yanshanian in the area. The lower rhenium content in molybdenite of Huangshaping deposit suggests that the ore-forming material was mainly of crust origin.  相似文献   

6.
The polymetallic Dushiling W-Cu deposit is a large, altered, skarn-type deposit, located in the northeastern part of the Miao'ershan-Yuechengling pluton, China. Two types of granite have been identified in the deposit: a medium-grained porphyritic biotite granite, and a medium- to fine-grained biotite granite. Both are spatially and temporally related to ore bodies, suggesting they may be the source of mineralization in the deposit. A medium- to fine-grained porphyritic biotite granite is exposed at the surface in the region of mineralization. U-Pb dating of zircons yielded magmatic ages of 423 Ma for the medium-grained porphyritic biotite granite and 421 Ma for the medium- to fine-grained porphyritic biotite granite, while a younger age(217 Ma) obtained for surface samples indicates later diagenesis. Thus, magmatism occurred during the Caledonian and Indosinian, respectively. The petrological and geochemical characteristics of the two Caledonian granites show that both are calc-alkaline and peraluminous.They are moderately enriched in Cs, Rb, U, and REE, and strongly depleted in Sr,Ba,P,and Ti; they show similar REE behavior,including negative Eu anomalies. These geochemical similarities suggest that the two granites were derived from the same source,although they were emplaced during different stages of the evolution of the magma. Furthermore, the granites are associated with mineralization, suggesting they were the source of mineralization in the Dushiling W-Cu deposit. Sm-Nd ages of scheelite from the Dushiling W-Cu deposit indicate that metallogenesis occurred at 417±35 Ma, while the two types of titanite, intergrown with scheelite, yield U-Pb ages of 423–425 Ma(in altered granite sample) and 218 Ma(in skarn sample). These ages place the main mineralization event in the late Caledonian, and later magmatic-hydrothermal activity occurred in the Indosinian. The ages obtained for the Dushiling W-Cu deposit in the western Nanling Range, northern Yuechengling, together with the occurrence and ages of the Niutangjie W deposit in southern Yuechengling, provide insight into the process of ore concentration during the Caledonian and Indosinian.  相似文献   

7.
Although a number of petrographic observations and isotopic data suggest that magma mixing is common in genesis of many granite plutons, it is still controversial whether the mantle-derived magmas were involved in granites. We carried out in this study a systematic analysis of in situ zircon Hf-O isotopes for three early Yanshanian intrusions dated at ca. 160 Ma from the Nanling Range of Southeast China. The Qinghu monzonite has very homogeneous zircon Hf-O isotopic compositions, εHf(t) =11.6±0.3 and δ18O=5...  相似文献   

8.
Foliated garnet-bearing granite, usually associated with high pressure and ultrahigh -pressure (UHP) metamophic rocks, is a particular rock-type extensively exposed in the Mesozoic Dabie-Sulu orogenic belt of China. This study focuses on deformation features and SHRIMP zircon dating of foliated garnet granite in a high-pressure metamorphic unit from Huwan, western Dabie Mountains in order to resolve discrepancies in current versions of its petrogenesis and structural evolution. SHRIMP dating reveals a zircon age of 762 ± 15 Ma (MSWD=1.7) for Huwan granites, representing the Middle to Late Neoproterozoic age of intrusion and crystallization. Field and microstructural studies show that the Huwan granite body underwent multiple-stage deformation. The deformation was manifested by an early stage of rootless folding and imposition of relict foliation (S1); an Indosinian main stage marked by imposition of north-dipping penetrative gneissosity (S2) and development of ductile shear zones under NNE-SSW directed compression; and a final Indosinian stage of southward thrusting of the Huwan high-pressure unit. Shallow level extension prevailed after the Late Triassic, giving rise to south-dipping thrust faults and north-dipping normal faults. Supported by the National Natural Science Foundation of China (Grant Nos. 40802046 and 40334037) and the Project of Science & Technology Research and Development from Sinopec (Grant No. P02009)  相似文献   

9.
Northern Xinjiang has been an idea and focus re-gion for post-collisional tectonic-metallogenic re-search. The time span of post-collisional stage, as well as the time span of extrusion and extension gyration of a post-collisional stage, and the process and dynamicssetting of Paleozoic continental growth are the key problems[1-7]. According to the definition by Liegeois[8], Wang et al. (in press)1) proposed that the taphrogeosyncline sedimentary formation that unconformably overliesthe main c…  相似文献   

10.
The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzonitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02DX-137) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/238U ages of 229.4 ± 3.0 Ma and 230.4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/238U age of 231.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (∼230 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/238U apparent age of 1977±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of development of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.  相似文献   

11.
The Bashikaogong-Shimierbulake granitoid complex is about 30 km long and 2―6 km wide, with an area of 140 km2, located at the north margin of the Bashikaogong Basin in the north Altun terrain. It intruded into schist, metapelite and metatuff of Precambrian ages. This granitoid complex consists of darkish quartz diorite, grey granite, pink granite and pegmatite. Geochemically, the quartz diorite has I-type granite affinity and belongs to Calc-alkaline sereies, and the other gran- ites have S-type affinity and to high-K calc-alkaline series. Zircon SHRIMP U-Pb dating shows that the quartz diorite has a bigger age than those of other granites, which is 481.6±5.6 Ma for quartz diorite, 437.0±3.0 Ma―433.1±3.4 Ma for grey granite and 443±11 Ma―434.6±1.6 Ma for pink granite, re- spectively. Combined with regional geology, we think that the quartz diorite formed in tectonic envi- ronment related to oceanic crust subduction and the granites in post-collision.  相似文献   

12.
The intrusive bodies studied include Mafan diorites ((462.7±1.5) Ma,40Ar/39Ar amphibole plateau age), Duhudian granites ((293±12) Ma, U-Ph zircon age) and Suxianshi granites ((146.2±0.9) Ma) in Beihuaiyang area at the northern foot of Dabie Mountains, central China. Petrological studies indicate that all of them belong to I-type granitoid rocks. Among them, the Mafan and Duhudian stocks were formed by arc magmatism, while the Suxianshi pluton is a post-collisional granitic body. Three intrusive bodies have distinctive characteristics of structural deformation. The Mafan stock has a rather complicated structure pattern resulting from polyphase deformation during the Caledonian and Mesozoic, the Duhudian stock has been pronouncedly deformed during the Hercynian-Yanshanian events, while regional foliation is not pronounced within the Yanshanian Suxianshi stock. Combination of regional stratigraphic, regional structural and geochronological data shows that the Yangtze plate has experienced two episodes of subduction northward beneath the North China plate during the Paleozoic and following collisional events. The first phase of collision at about 400 Ma resulted in the formation of the Beihuaiyang crystalline basement and the Caledonian high-pressure metamorphism in Dabie orogenic zone, and a late phase of continent-continent collision (~230 Ma) is responsible for the Triassic ultrahigh- and high-pressure metamorphism in Dabie Mountains and for orogenic uplift of the Dabie Mountains. It is suggested that the Beihuaiyang tectonic belt at the northern foot of the Dabie Mountains is a multicyclic suture.  相似文献   

13.
Emplacement P-T condition estimations using granites are important for understanding metamorphic and erosional processes of orogenic belt.Granites are widespread in South China and a majority of them are peraluminous.Particularly,over 91%of the Indosinian granites exposed in the region are peraluminous in composition.It is extremely hard to determine the pressure of intrusion of these peraluminous granites due to the absence of amphibole,a good mineral barometer commonly identified in metaluminous granites.Muscovite is a common mineral in peraluminous granites,certain kind of it could be used as a mineral barometer to constrain the emplacement pressure of peraluminous granites.In this paper,results of petrographic and geochemical studies of muscovites from the Indosinian and early Yanshanian two-mica granites at the Longyuanba in the eastern Nanling Range are reported.Based on petrographic studies,the primary muscovite can be discriminated from the secondary muscovites.Muscovites from the Indosinian two-mica granites are enriched in Ti,Al,Mg,and Na,and depleted in Fe and Mn.Geochemically,these muscovites were considered as primary,whereas those from the Yanshanian two-mica granites fall into the area of secondary muscovite on discrimination diagrams.Barometer estimations show that pressures calculated for primary muscovites are accurate,but those calculated for secondary muscovites are overestimated.The average pressure of emplacement of the Longyuanba Indosinian two-mica granites is 5.9 kbar,corresponding to~19 km in depth,suggesting that the Indosinian granitic magmas were probably generated by partial melting of a thickened crust root in a compressional tectonic setting.  相似文献   

14.
Granitoids in the Hida region of Japan encompass two main rock types: younger type‐1 granites and older type‐2 granites. Sensitive high mass‐resolution ion microprobe (SHRIMP) U–Pb zircon dating of older type‐2 granites collected from the Tateyama area show similar ages of 245 ± 2 Ma and 248 ± 5 Ma for two gneissose granites, while a significantly younger intrusion age of 197 ± 3 Ma was determined for the younger type‐1 granites collected from the Hayatsukigawa River which belongs to the Okumayama pluton. A felsic gneiss sample (07HI‐3) collected from the right bank of the Hayatsukigawa River yielded multiple complex ages at 330 ± 6 Ma, indicating the timing of the Hida regional tectono‐thermal events that formed the Hida gneisses; 243 ± 8 Ma, representing the timing of intrusion of the augen granite; and 220 Ma, indicating the timing of regional dextral ductile shearing that caused a repeated recrystallization of metamorphic rocks in the study area. Considering the geochronological data, the rock types and assemblages, basement, and Sr–Nd isotopic constraints, we propose that the Hida Belt separated from the Jiamushi massif, which is located in the eastern margin of the Central Asian Orogenic Belt.  相似文献   

15.
The Nanling metallogenic belt in South China is characterized by well-developed tungsten-tin mineralization related to multiple-aged granitoids. This belt is one of the 5 key prospecting and exploration areas among the 19 important metallogenic targets in China. Important progress has been made in recent years in understanding the Nanling granitoids and associated mineralization, and this paper introduces the latest major findings as follows: (1) there exists a series of Caledonian, Indosinian, and Yanshanian W-Sn-bearing granites; (2) the Sn-bearing Yanshanian granites in the Nanling Range form an NE-SW trending aluminous A-type granite belt that stretches over 350 km. The granites typically belong to the magnetite series, and dioritic micro-granular enclaves with mingling features are very common; (3) the Early Yanshanian Sn- and W-bearing granites possess different petrological and geochemical features to each other: most Sn-bearing granites are metaluminous to weakly peraluminous biotite (hornblende) granites, with zircon ?Hf(t) values of ca. ?2 to ?8, whereas most W-bearing granites are peraluminous two-mica granites or muscovite granites with ?Hf(t) values of ca. ?8 to ?12; (4) based on the petrology and geochemistry of the W-Sn-bearing granites, mineralogical studies have shown that common minerals such as titanite, magnetite, and biotite may be used as indicators for discriminating the mineralizing potential of the Sn-bearing granites. Similarly, W-bearing minerals such as wolframite may indicate the mineralizing potential of the W-bearing granites. Future studies should be focused on examining the internal relationships between the multiple-aged granites in composite bodies, the metallogenic peculiarities of multiple-aged W-Sn-bearing granites, the links between melt evolution and highly evolved ore-bearing felsic dykes, and the connections between granite domes and mineralization.  相似文献   

16.
The samples from the hidden Daqiling muscovite monzonite granite, which has recently been recognized within the Limu Sn-polymetallic ore field, have been analyzed for zircon U-Pb ages and whole rock geochemical and Nd-Hf isotopic compositions to discuss its genesis, source, and tectonic setting. LA-ICP-MS zircon U-Pb dating indicates that the granite crystallized in the late Indosinian (224.8±1.6 Ma). The granite is enriched in SiO2 and K2O and low in CaO and Na2O. It is strongly peraluminous with the A/CNK values of 1.09–1.20 and 1.4 vol%–2.7 vol% normal corundum. Chondrite-normalized REE patterns show slightly right-dipping shape with strongly negative Eu anomalies (δEu =0.08–0.17). All samples show enrichment of LILEs (Cs, Rb and K) and HFSEs (U, Pb, Ce and Hf), but have relatively low contents of Ba, Sr and Ti. The zircon saturation temperatures (T zr) are from 711 to 740°C, which are slightly lower than the average value of typical S-type granite (764°C). The granite has negative ? Nd(t) and ? Hf(t) values, which change from ?9.1 to ?10.1 with the peak values of ?9.2 to ?9.0 and from ?3.7 to ?12.6 with the peak values of ?6 to ?5, respectively. The T DM C (Nd) and T DM C (Hf) values are 1.74–1.82 Ga with the peak values of 1.73–1.75 Ga and 1.49–2.04 Ga with the peak values of 1.5–1.6 Ga, respectively. These characteristics reveal that the source region of the granite is dominantly late Paleoproterozoic to early Mesoproterozoic crustal materials. Seven inherited magmatic zircons are dated at the age of 248.6±4.3 Ma, which suggests the existence of the early Indosinian granite in Limu area. These zircons have the ? Hf(t) values of ?6.7–?2.3, similar to those of the Daqiling granite, implying the involvement of the early Indosinian granite during the formation of the Daqiling granite. Inherited zircon of 945±11 Ma has the ? Hf(t) and T DM(Hf) values of 8.7 and 1.14 Ga, respectively, compatible with those of the Neoproterozoic arc magmatic rocks in the eastern Jiangnan orogenic belt. Therefore we inferred that Neoproterozoic arc magma might have been involved in the formation of the Daqiling granite, and that the Neoproterozoic arc magma belt and continent-arc collision belt between the Yangtze and Cathaysia Blocks might have extended westsouthward to Limu region. It is proposed that the underplating of mantle materials triggered by crustal extension and thinning resulted in partial melting of crustal materials to form the Daqiling granite in the late Indosinian under post-collisional tectonic setting.  相似文献   

17.
Seon-Gyu  Choi  V. J. Rajesh  Jieun  Seo  Jung-Woo  Park  Chang-Whan  Oh  Sang-Joon  Pak  Sung-Won  Kim 《Island Arc》2009,18(2):266-281
Collision between the North and South China continental blocks began in the Korean peninsula during the Permian (290–260 Ma). The Haemi area in the Hongseong collision belt (proposed as the eastern extension in South Korea of the Dabie–Sulu collision zone of China) within the Gyeonggi Massif comprises post-collisional high Ba–Sr granite with intermediate enclaves that intruded into the Precambrian rocks. The intermediate enclaves have a shoshonitic affinity whereas the granite is a high-K calc-alkaline variety. The chondrite-normalized rare earth element (REE) pattern with relative enrichment of LREE over HREE and absence of a significant negative Eu anomaly typifies both enclaves and granite. Geochemical similarities of enclaves and granite are attributed to the involvement of enriched mantle sources in their genesis. However, dominant crustal components were involved in the formation of high Ba–Sr granites. A granite crystallization age of 233 ± 2 Ma was obtained from SHRIMP U–Pb zircon dating. This age is slightly younger than the Triassic collision event in the Hongseong Belt. Geochemical data, U–Pb zircon age, and regional tectonics indicate that the Haemi high Ba–Sr granite formed in a post-collisional tectonic environment. A Mesozoic post-collisional lithospheric delamination model can account for the genesis of high Ba–Sr granite in the Haemi area.  相似文献   

18.
Researches over the last 20 years show that the orogenic belt remains rather active after plate colli-sion[1,2]. A complete orogenic cycle in the last period of the Wilson cycle can be defined by three stages of development[3]: (1) horizontal contraction and crustal thickening due to collision, as well as formation of topography and the crustal and lithospheric root; (2) eclogite facies metamorphism of the crustal root; and (3) delamination of the crustal root or lithospheric mantle, extension…  相似文献   

19.
Granitoid intrusives such as Saishitenshan, Tuanyushan, Aolaohe and Sanchagou occur widely in the western segment of North Qaidam. All these bodies trend NW, roughly parallel to the regional structure. Zircon SHRIMP dating for these granites show that they range in age from Ordovician to Permian; 465.4±3.5 Ma for Saishitenshan, 469.7±4.6 Ma and 443.5±3.6 Ma for Tuanyushan, 372.1±2.6 Ma for Aolaohe, and 271.2±1.5 Ma and 259.9±1.2 Ma for Sanchagou. Both the Tuanyshan and Aolaohe plutons record two distinct intrusive events. Geochemically, the early Paleozoic granites have an island arc or active continental margin affinity, and their protolith may have been Mesoproterozoic oceanic crust derived from depleted mantle. The protolith of the late Paleozoic granites may have been Mesoproterozoic lower crust from the root of an island arc with the magmas reflecting a mixture of mantle and crustal material.  相似文献   

20.
The Phan Si Pan zone in northwest Vietnam is an important tectonic unit for understanding the geological evolution of the southeast Asian Block. Numerous late Permian A‐type granites outcrop in this zone. In this study, new geochemical and geochronological data derived from the Muong Hum alkaline granitic pluton in the Phan Si Pan zone were investigated for its petrogenesis and tectonic setting. Zircon U–Pb analyses of three samples yielded 206Pb/238U ages of (251.1 ±3.5) Ma, (251.2 ±3.8) Ma, and (253.9 ±1.5) Ma, respectively, coinciding with the ages of the acid member of magma from Emeishan large igneous province, southwest China. The Muong Hum granite has 10 000 × Ga/Al and A/CNK values of 4.70–4.93 and 0.87–0.90, respectively, as well as negative Eu anomalies. It shows significant depletion of Ba, Sr, Ti, and P, similar to features of A‐type granite. Zircons have positive εHf(t) values (+1.9 to +8.6) and Hf model ages (TDM1) of 595–846 Ma, originating a mantle source. Compared with the Panzhihua A‐type granite of the southwest China domain and other A‐type plutons of the Phan Si Pan zone, including Ye Yen Sun, Phu Sa Phin, Nam Xe, Tam Duong Phan Si Pan, and Taihe, the geochemical characteristics and zircon Hf isotopic compositions of the Muong Hum granite demonstrate an affinity of mantle magma. It is believed that the Phan Si Pan zone is an important part of Emeishan large igneous province. It was reworked by the Cenozoic Aillaoshan‐Red River shear fault to its present location.  相似文献   

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