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1.
http://www.sciencedirect.com/science/article/pii/S1674987115000882   总被引：1，自引：0，他引：1  
A detailed vibrational Raman-IR spectroscopic and diffractional analyses have been performed on basalts from two locations from Tenerife Island:(1) the Arenas Negras volcano which belongs to the historical eruption not showing visible alteration and(2) Pillow Lavas zone from Anaga Massif which shows a clearly fluid-rock interaction caused by submarine alteration.These places have been extensively studied due to its similarity with the surface of Mars.The analysis is based on the mineral detection of selected samples by a Micro-Raman study of the materials.The complementary techniques have confirmed the mineralogy detected by the Raman measurement.The results show a volcanic environment behavior with primary phases like olivine,pyroxene,and feldspar/plagioclase.Moreover,the presence of accessory minerals or secondary mineralization like phosphate,iron oxides,zeolite or carbonates shows the alteration processes on each outcrop.The variation in the crystallinity and amorphous phases is related to fluid-rock interaction caused by hydrothermal episodes and external weathering processes,which shows several analogies with the ancient volcanic activity from Mars.  相似文献   

2.
Sedimentary basins containing igneous intrusions within sedimentary reservoir units represent an important risk in petroleum exploration. The Upper Triassic to Lower Jurassic sediments at Wilhelm?ya(Svalbard) contains reservoir heterogeneity as a result of sill emplacement and represent a unique case study to better understand the effect of magmatic intrusions on the general burial diagenesis of siliciclastic sediments. Sills develop contact metamorphic aureoles by conduction as presented in many earlier studies. However, there is significant impact of localized hydrothermal circulation systems affecting reservoir sediments at considerable distance from the sill intrusions. Dolerite sill intrusions in the studied area are of limited vertical extent(～12 m thick), but created localized hydrothermal convection cells affecting sediments at considerable distance(more than five times the thickness of the sill)from the intrusions. We present evidence that the sedimentary sequence can be divided into two units:(1) the bulk poorly lithified sediment with a maximum burial temperature much lower than 60-70 ℃,and(2) thinner intervals outside the contact zone that have experienced hydrothermal temperatures(around 140 ℃). The main diagenetic alteration associated with normal burial diagenesis is minor mechanical plastic deformation of ductile grains such as mica. Mineral grain contacts show no evidence of pressure dissolution and the vitrinite reflectance suggests a maximum temperature of ～40 ℃. Contrary to this, part of the sediment, preferentially along calcite cemented flow baffles, show evidence of hydrothermal alteration. These hydrothermally altered sediment sections are characterized by recrystallized carbonate cemented intervals. Further, the hydrothermal solutions have resulted in localized sericitization(illitization) of feldspars, albitization of both K-feldspar and plagioclase and the formation of fibrous illite nucleated on kaolinite. These observations suggest hydrothermal alteration at T 120-140 ℃ at distances considerably further away than expected from sill heat dissipation by conduction only, which commonly affect sediments about twice the thickness of the sill intrusion. We propose that carbonate-cemented sections acted as flow baffles already during the hydrothermal fluid mobility and controlled the migration pathways of the buoyant hot fluids. Significant hydrothermally induced diagenetic alterations affecting the porosity and hence reservoir quality was not noted in the noncarbonate-cemented reservoir intervals.  相似文献   

3.
This paper presents REE abundance pattern and REE geochemistry of granodiorite porphyry, skarns, as well as late hydrothermal alterations in the Tongshan copper deposit, Guichi County and, in the light of their similarities and variations, deals with the genesis of the skarns and the transformation process of the post-skarn hydrothermal alterations. On such a basis, the inference is drawn that the skarn-forming solution was produced by further fractionation of residual magma, thus belonging to a transitional fluid between residual magma and hydrothermal solution which, with the continuous variation of its components during the metasomatism, tended to become a hydrothermal solution.  相似文献   

4.
There are two main types of iron deposits in the Middle-Lower Yangtze Valley district.Both of them underwent post-magmatic hydrothermal processes during ore formation.Iron in the hydrothermal ore bodies was derived largely through mobilization from substantially consolidated diroitic intrusives.Wall-roch alteration zonation indicates that iron-mobilizing hydrothermal fluids evolved in a trend of decreasing alkalinity,which is suggested by regularly distributed wall-rock alterations formed by iron-mobilizing hydrothermal fluids and is in contradiction with the current chloride,chloride complex and bicarbonate models for iron mobilization.The close association of carbonatization with iron ores and the high concentrations of reduced gases such as CO,CH4 and H2 in fluid inclusions suggest that iron is most probably transported in the form of iron carbonyls during post-magmatic hydrothermal processes. In the light of the iron carbonyl mobilization model,explanations are made of the constraints on ores of some geologic factors such as melanocratic alteration,carbonatization,carbonate strata,structural fractures,cyptoexplosive pipes and embryo ores.  相似文献   

5.
In recent years, a considerable amount of microscopic spherules have been found in concentrates recovered from some stratabound gold deposits occurring in Middle-Upper Triassic turbidite series in northwestern Sichuan. Study indicates that these spherules are cosmic dust. It is the first time that cosmic dust of extraterrestrial origin has been found in hydrothermal gold deposits in China.The spherules are steel-grey in colour and show metallic luster. Their grain size is commonly less than 100 μm. According to their composition, they belong to chromium-rich iron cosmic dust. The spherules have complex and diverse microscopic structures and textures, i.e. they show a very distinct Widmanstaten structure.The variation of cosmic dust content in gold deposits exhibits a positive correlation with the mineralization intensities and hydrothermal alteration. Such a relation indicates that the ore sub- stances may transport not only mechanically but also may chemically in hydrothermal solutions.  相似文献   

6.
Uranium-bearing hydrothermal solutions during the stage of ore deposition are weakly alkaline and of the Ca^2 -Na^ /HCO3^- -F^- type.UO2(CO3)2^2- and UO2F4^-, are dominant in the hydrothermal solutions with respect to their activity.Wall-rock hydrothermal alterations ,temperature and pressure drop and the reducing capability of rock assemblage (Δeh) led to a decrease in Eh of the hydrothermal solutions and an increase in Eh at which uranium began precipitating.Therefore,the mechanism of uranium precipitation is essentially the reduction of uranium complexes.The granite-type uranium deposits are the most important type of uranium resources in China.Discussions will be made in this paper concerning the hydrothermal speciation and precipitation mech-anisms of uranium complexes in the light of fluid inclusion and geological data from some major de-posits of this type in South China.  相似文献   

7.
Experiments indicate that the solubility of cassiterite can be enhanced by increasing either acidity or alkalinity in hydrothermal solutions as a consequence of the duality of tin.The minimum solubility of cassiterite is found in neutral solutions.F-and CL-coordination compounds of Sn can alternate with hydroxyl coordination compounds with changing pH in the solutions.In this case,F^- and Cl^- and OH^- can be substituted with each other.The dissolution reaction of cassiterite is of reducing nature.High temperature and acidic reducing environment are favorable for the dissolution of cassiterite and the trans-port of Sn^2 compounds in fluids or solutions.High-temperature fluoride and chloride fluids can all dissolve,extract and enrich Sn to form F^- and /or Cl-coordination compounds,However,Fplays a more important role than Cl.F-coordination compounds are more stable and efficient than Cl-coordination compounds during the transport an enrichment of Sn in melts or solutions.The solubili-ty of cassiterite and the amount of Sn extracted from granitic melt depend not only on T,P,pH and Eh in the fluids or solutions,but also on the amounts of dissociated F^- and Cl^- in the fluids.  相似文献   

8.
The exhalation origin of the ankerite-siliceous rocks associated with Pb-Zn mineralizations in the Devonian system of Qinling is discussed in the light of geologic setting,sedimentary-tectonic environment,lithological and chemical characteristics.On this basis,criteria for distinguishing them and their potential role as an indicator in prospecting are described.Ankerite-siliceous rocks are developed in the strata-bound Pb-Zn polymetallic belt in the Devonian system of Qinling.They are microcrystalline,dark grey and compact in appearance and are commonly carbonaceous,As a persistent ore-bearing horizon in the region,their genetic relation to the Pb-Zn deposits in generally accepted.However,a consensus has yet to be reached among geologists concerning their origein as a product of hydrothermal metasomtism at the late stage of sedimentation or as exhalite resulting from submarine exhalation.Accumulating evidence from direct observations on modern submarine hydrothermal systems strongly indicates that seafloor exhalation is a much more common geologic process than previously thought nd its metallogenic implications have long been overlooked.Characteristics of the ankerite-siliceous rocks as a product of exhalation and their significance as a guide in prospecting are described on the basis or geological setting,lithology,lithochemistry,REE,and isotopic and trace element features.  相似文献   

9.
For the iron deposits occurring in andesitic volcaic rocks of the Lower Yangtze Area.the genetic model for porphyrite iron deposits was proposed by chinese geologists more than ten years ago on the basis of their detailed studies in the Nanjing-Wuhu Basin.It comprises a set of deposits of different genetic types ranging from late magmatic segregation ,ore-magma injection,pneumato-hydatogenetic replacing and hydrothermal filling as well as sedimentary origin.The deposits are closely connected with the gabbro-diorite porphyrite subvolcanic intrusive bodies both in space and in genesis.Miner4alization and wall-rock alteration are consistent with the history of the magmatic evolution.Geochemical studies on trace elements and S,O,Sr isotopes have proved that the porphyrite iron deposits are of magmatic origin,The proposed model may be applied to iron ores associated with andesitic volcanites,for example,in Chile,Mexico,Pakistan,Turkey,etc.  相似文献   

10.
The Kengdenongshe deposit is a newly discovered large Au-Ag-Pb-Zn polymetallic deposit in the eastern Kunlun metallogenic belt, and the genetic relationship between Pb-Zn-rich ore bodies and Au-rich ore bodies in this deposit is controversial. Therefore, comparative studies of mineralization, alteration, and fluid inclusions in the two types of ore bodies were carried out with the statistical analysis of the correlation among ore-forming elements of Au, Ag, Pb and Zn. The results show that, from north to south, the mineralization changes gradually from Pb-Zn-rich to Au-rich with the wall-rock alteration from silicification-epidotization to baritization-marbleization-silicification. In addition, the structures of Pb-Zn-rich ores indicate a hydrothermal sedimentary origin with the late hydrothermal superposition, while those of Au-rich ores show features of hydrothermal origin. Besides, based on the study of fluid inclusions in this mining area, the ore-forming fluid of Pb-Zn-rich ores is low temperature (focus on 150-170°C) and low-medium salinity (1.74%-10.24% NaCleqv), while that of Au-rich ores displays low-medium temperature (manily 130-250°C) with low-medium salinity (0.35%-10.24% NaCleqv). Pb-Zn and Au-Ag show positive correlation (correlation coefficient r>0.25), but Au is poorly correlated with Pb and Zn (correlation coefficient r<0.15). However, to due to the late stage hydrothermal superimposition, Au is rather well correlated with Pb in high grade ores. In summary, there may exist two epochs of mineralization in the Kengdenongshe polymetallic deposit. The early one is Pb-Zn mineralization stage with characteristics of hydrothermal sedimentary origin, and the ore-forming fluid may be derived from the mixture of magmatic water and seawater. While the later one is Au mineralization stage, having characteristics of hydrothermal origin with subsequent hydrothermal superimpositions, and the ore-forming fluid is mainly derived from magmatic water that mixed with meteoric water. © 2018, Science Press. All right reserved.  相似文献   

11.
The Tongling area is one of the 7 ore-cluster areas in the Middle-Lower Yangtze metallogenic belt,East China,and has tectonically undergone a long-term geologic history from the late Paleozoic continental rifting,through the Middle Triassic continent-continent collision to the Jurassic-Cretaceous intracontinental tectono-magmatic activation.The Carboniferous sedimentary-exhalative processes in the area produced widespread massive sulfides with ages of 303-321 Ma,which partly formed massive pyrite-Cu deposits,but mostly provided significant sulfur and metals to the skarn Cu mineralization associated with the Yanshanian felsic intrusions. To understand the Carboniferous submarine hydrothermal system,an area of about 1046 km~2 was chosen to carry out the geological fluid mapping.Associated with massive sulfide formation,footwall sequences 948 m to 1146m thick,composed of the Lower Silurian-Upper Devonian sandstone,siltstone and thin-layered shale,were widely altered.This hydrothermal alteration is interpreted to reflect large- scale hydrothermal fluid flow associated with the late Paleozoic crustal rifting and subsidence.Three hydrothermal alteration types,i.e.,deep-level semiconformable silicification(S_1),fracture-controlled quartz-sericite-pyrite alteration(S_(2-3)),and upper-level sub-discordant quartz-sericite-chlorite alteration(D_3),were developed to form distinct zones in the mapped area.About 50-m thick semiconformable silicification zones are located at～1-km depth below massive sulfides and developed between an impermeable shale caprock(S_1)and the underlying Ordovician unaltered limestone. Comparisons with modern geothermal systems suggest that the alteration zones record a sub-seafloor aquifer with the most productive hydrothermal fluid flow.Fracture-controlled quartz-sericite-pyrite alteration formed transgressive zones,which downward crosscut the semiconformable alteration zones, and upwards grade into sub-discordant alteration zones that enveloped no economic stringer- stockwork zones beneath massive sulfides.This transgressive zone likely marks an upflow path of high- flux fluids from the hydrothermal aquifer.Lateral zonation of the sub-discordant alteration zones and their relationship to overlying massive sulfide lenses suggest lateral flows and diffusive discharging of the hydrothermal fluids in a permeable sandstone sequence.Three large-sized,14 middle-small massive sulfide deposits,and 40 massive sulfide sites have been mapped in detail.They show regional strata- bound characters and two major styles,i.e.,the layered sheet plus strata-bound stringer-style and the mound-style.Associated exhalite and chemical sedimentary rock suites include(1)anhydrite-barite,(2) jasper-chert,(3)Mg-rich mudstone-pyrite shale,(4)barite lens,(5)siderite-Fe-bearing dolomite,and (6)Mn-rich shale-mudstone,which usually comprise three sulfide-exhalite cyclic units in the area. The spatial distribution of these alteration zones(minerals)and associated massive sulfides and exhalites,and regional variation inδ~(34)S of hydrothermal pyrite and inδ~(18)O-δ~(34)C of hanging wall carbonates,suggest three WNW-extending domains of fluid flow,controlled by the basement faults and syn-depositional faults.Each fluid domain appears to have at least two upflow zones,with estimated even spacing of about 5-8 km in the mapped area.The repeated appearance of sulfide-sulfate or sulfide-carbonate rhythmic units in the area suggests episodically venting of fluids through the upflow conduits by breaking the overlying seals of the hydrothermal aquifer.  相似文献   

12.
The Lugiin Gol nepheline syenite intrusion, Mongolia, hosts a range of carbonatite dikes mineralized in rare-earth elements(REE). Both carbonatites and nepheline syenite-fluorite-calcite veinlets are host to a previously unreported macroscale texture involving pseudo-graphic intergrowths of fluorite and calcite. The inclusions within calcite occur as either pure fluorite, with associated REE minerals within the surrounding calcite, or as mixed calcite-fluorite inclusions, with associated zirconosilicate minerals. Consideration of the nature of the texture, and the proportions of fluorite and calcite present(～29 and 71 mol%,respectively), indicates that these textures most likely formed either through the immiscible separation of carbonate and fluoride melts, or from cotectic crystallization of a carbonatefluoride melt. Laser ablation ICP-MS analyses show the pure fluorite inclusions to be depleted in REE relative to the calcite. A model is proposed, in which a carbonate-fluoride melt phase enriched in Zr and the REE, separated from a phonolitic melt, and then either unmixed or underwent cotectic crystallization to generate an REE-rich carbonate melt and an REE-poor fluoride phase. The separation of the fluoride phase(either solid or melt) may have contributed to the enrichment of the carbonate melt in REE, and ultimately its saturation with REE minerals. Previous data have suggested that carbonate melts separated from silicate melts are relatively depleted in the REE, and thus melt immiscibility cannot result in the formation of REE-enriched carbonatites. The observations presented here provide a mechanism by which this could occur, as under either model the textures imply initial separation of a mixed carbonate-fluoride melt from a silicate magma. The separation of an REEenriched carbonate-fluoride melt from phonolitic magma is a hitherto unrecognized mechanism for REE-enrichment in carbonatites, and may play an important role in the formation of shallow magmatic REE deposits.  相似文献   

13.
Amphibole is a rock-forming mineral widely existing on the earth. It is easily dissolved and altered during the later stage of diagenesis and mineralization, and often forms chloritization, which is an important indicator for prospecting. To explore amphibole's dissolution process and alteration mechanism, dissolution experiments were carried out under acidic conditions using pargasite-rich amphibole as raw material, and the effects of temperature, p H, and experiment duration on amphibole alteration were investigated. Experimental samples and products were analyzed using X-ray diffractometer, field emission scanning electron microscope, electron probe micro analyzer, and transmission electron microscopy. It was found that many pores and erosion edges are produced after amphibole dissolution, and there is a clear interface between the dissolved residual portion and the parent. The dissolved residual portion remains in the amphibole phase, but as the temperature and time increase, the intensity of the diffraction peak of the phase in the product decreases, and the peak position shifts to a small angle. Many clay minerals such as chlorite and griffithite formed on the amphibole surface. In an environment with strong acidity(p H=3), the amount of chamosite increases with temperature(180°C→210°C→240°C), whereas clinochlore is only increased in a 150–210°C environment. Griffithite growth was observed in the acidic(p H=6) and low temperature(180°C) environments. Based on this analysis, large radius Cl– enters the amphibole lattice or cracks to promote dissolution. The Al-poor and Ca-and Fe-rich regions between the edge and core of the amphibole are caused by dynamic equilibrium in amphibole dissolution and alteration process, which is an essential indicator for the beginning of amphibole dissolution-alteration. Diffusion and the coupled dissolution-reprecipitation mechanism accomplishes the process of dissolution and alteration to form clay minerals. The energy of the system determined by temperature and p H is the key to controlling the rate of growth and nucleation of clay minerals. High temperature and strong acidity will dissolve more iron from amphibole, which is conducive to chlorite growth. Compared to chlorite, griffithite is more sensitive to temperature. Griffithite attaches on the amphibole surface with a star-like in a weak acid and low-temperature environment. The results of this study can provide a mineralogical basis for the analysis of hydrothermal alteration processes and the division of alteration zones.  相似文献   

14.
The Jinsha River-Lancang River-Nujiang River area is one of the important prospect areas for noble metal and nonferous metal deposits of China. Of a great variety of gold deposits present in this area, the following types seem to be economically most valuable and promising: tectonic alteration type in ophiolitic melange; polymetallic quartz vein type related to intermediate-acid intrusions; finely disseminated type in fracture zones; mixed hydrothermal type in tectonic fractures of carbonate rocks; hydrothermal type related to subvolcanic rocks; volcanic-hot spring type; submarine volcano exhalation-sedimentary-hydrothermal reformation type. Metallogenic epochs are exclusively Mesozoic and Cenozoic, and ore deposits and orebodies are controlled by linear structures. Magmatic activity has affected gold mineralization in varying degrees, and gold deposits are basically of mesothermal-epithermal type with ubiquitous and intense alterations. Ore-forming materials and hydrothermal solutions show multi-source character.  相似文献   

15.
Fluidization processes based on experiments are reviewed to gain some useful insights and comparisons with those that occur in hydrothermal systems. Field and petrographic work, and microscope observation were carried out on samples from the Qiyugou Au-bearing breccia pipes from the East Qinling region, Henan Province. Evidence from macro- and micro-textures suggests that the style of breccias in the Qiyugou area can be grouped into three types： （1） jigsaw fit-stockwork texture, in which the interval between clasts is marked by fractures or filled with calcite or quartz veins; （2） larger breccias that are supported by smaller breccias, rock flour and alteration materials; in this type clasts moved over short distances, creating open spaces; （3） fluidized texture, where the clasts of different lithologies have rounded shapes. These observations are compared with those resulting from experiments on fluidization processes. The results of this comparison suggest that fluidization is an important geological process in the formation of the Qiyugou Au-bearing breccia pipes and gold mineralization. In addition, fluidization processes such as expansion, bubbling, slugging, channeling and spouting must have contributed to the formation of the pipes and were conducive to the development of gold mineralization. In the Qiyugou breccia pipes, gold mineralization occurs as disseminations, in stockwork veins, and open space infills. The ore zones form subparallel sheets that are nearly perpendicular to the walls of the pipes.  相似文献   

16.
Three-phase NaCl-H_2O fluid inclusions featuring halite dissolution temperature(Tm)higher than vapor bubble disappearance temperature(T_h) are commonly observed in porphyry copper/molybdenum deposits,skarn-type deposits and other magmatic- hydrothermal ore deposits.Based on |ΔV_1|(the absolute value of volume variation of NaCl-H_2O solution in a heating or cooling process of inclusions)= |ΔV_s|(the absolute value of volume variation of the halite crystal in a heating or cooling process of inclusions) and on the principle of conservation of the mass of NaCl and H_2O,we systematically calculated the densities of NaCl-H_2O solutions in the solid-liquid two-phase field for temperatures(T_h) from 0.1℃ to 800℃ and salinities from 26.3 wt%to 99.2wt%.Consequently for the first time we obtained the upper limit of the density of NaCI-H_2O solutions in the solid-liquid twophase field for T_bT_m inclusions with variant salinities.The results indicate that for inclusions of the T_hT_m type with the same T_h,the higher the T_m or salinity is,the higher the density of the NaClsaturated solution will be.If a group of fluid inclusions were homogeneously trapped,they must have the same T_h value and the same T_m or salinity value.This may be used to distinguish homogeneous,inhomogeneous,and multiple entrapments of fluid inclusions.  相似文献   

17.
Auriferous quartz veins in the Bankuan gold deposit occur in the interlayer broken zone of the basal conglomerate of the Tietonggou Formation or at the unconformity between the Tietonggou Formation and the crystalline basement.The composition of fluid inclusions in the minerals indicates that the nature and composition of ore-forming hydrothermal solutions show a drastical change soon after the solutions reached the Tietonggou Formation from the crystalline basement,resulting in gold precipitation.So the Bankuan gold deposit can be assigned to the conglomerate stata-bound-type deposits.137 thermometric data are concentrated in the three ranges 400-340℃,330-220℃ and 180-160℃,representing three episodes of metalogenesis,Oxygen isotope studies demonstrate the evolution of ore-forming hydrothermal solutions from early metamorphic to late meteoric,Diversity of ore-forming materials dominated by deep-source material is supported by sulphur and lead isotope data.From the above discussions it may be concluded that the deposit formed by metamorphism induced as a result of Mesozoic northward intracontinental subduction along the Machaoying fault.  相似文献   

18.
斑岩铜（钼）矿成矿作用的地球化学特征   总被引：1，自引：0，他引：1  
Dealt with in this paper are some geochemical characteristics of mineralization of porphyry copper deposits, especially those observed in intrusive bodies, wa11 rocks, alteration zones, ores and individual pyrites. Productive intrusions have been correlated with barre nones from such aspects as major and trace elements, copper contents of biotite and pyrite,and distribution pattern of copper. In the mineralized rocks, trace elements show apparent zoning surrounding ore bodies; major and trace dements seem to show some reguIarity of variation in the process of alteration, and as a result each alteration zone displays its own peculiar element combination. Trace dements in ores can provide information on the genesis of ore deposits, thus of great help in distinguishing ore types while those in pyrites may be indicative of mineralization, provide dues for distinguishing orebearing from barren rocks,and reflect the degree of erosion of ore bodies.  相似文献   

19.
This paper reviews the features of several tungsten ore deposits in southern China, including the Shezhuyuan, Yaogangxian, Xihuashan, Danping, Yiatang and Dajishan mines. The authors think that the formation depth of greisen-type deposits is intermediate between the depths of pegmatite- and porphyry- type deposits. Using phase diagrams of the model system K2O-AhO3-SiO2-H2O-HF, the formation mechanism of greisens has been argued. The variation of mineral assemblages from K-feldspar, muscovite to topaz reflects a gradual increase in acidity. This variation can be used as a criterion to appreciate the depth of mineralization. Equilibria of tungsten minerals in greisen and skarn deposits can be depicted on chemical potential diagrams of the model system CaO-FeO-WO3-CO2-F2O-1. The assemblage wolframite fluorite is shown to have been transformed to scheelite magnetite with decreasing μHP. Depending on CO2 activity in the fluids, there are two distinct phase diagrams.One shows that wolframite is incompatible with calcite, and the other demonstrates that scheelite is incompatible with rhodochrosite. On the phase diagrams of the model system FeO-MnO-WO3-F2S-1, huebnerite is transformed to ferberite with increasing μP1O-1orμF2S-1,During the replacement of wolframite by scheelite, the wolframite residue must have been enriched in Mn.  相似文献   

20.
阳储岭斑岩钨钼矿床地质地球化学特征及其成因探讨   总被引：5，自引：0，他引：5  
张玉学 《地球化学》1982,(2):122-132,217
The Yangchuling porphyry W-Mo-deposit is a new-type tungsten deposit discovered recently in southern China. Being of certain economic significance, this type of deposits promises some new prospects for the availability of increasing tungsten resource. The ore-bearing rock mess, intermediate to acid in composition, is a composite rock body resulted from comagmatic, multiple-stage intrusion during Middle-Late Yanshan Period. Spatially, the rock mass is controlled by the Guangji-Anqing-Nanjing deep fault. As a typical porphyry deposit, the ore-bearing rocks (granodiorite porphyry,mozonitic granite porphyry, and camouflage breccia) belong to sub-volcanic facies characteristic of near-surface environment. The rocks have suffered, strong hydrothermal alteration which is closely related to mineralization. The deposit is classified as mesoepithermal deposit and our study shows that W and Mo come from the granodiorite,granodiorite porphyry and mozonitie granodiorite porphyry, which are believed to be derived through remelting from some W-rich basement roeks contaminated with minor amounts of upper mantle material.  相似文献   

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