AbstractLamprophyre dikes and quartz veins in the Sizhuang gold deposit are used to date and unravel the Early Cretaceous stress regime in the Jiaodong Peninsula, North China Craton. The lamprophyre dikes are grouped into two major sets, trending NNW–SSE and NNE–SSW, respectively, and a subsidiary one, trending WNW–ESE, whereas the quartz veins trend mainly NNE–SSW. The age of lamprophyre dikes’ intrusion was robustly calculated at c. 119 Ma by phlogopite 40Ar–39Ar dating. The fuzzy clustering technique defined four stress states, which were grouped into three stress regimes in Sizhuang. Furthermore, these stress regimes were interrelated with two regional far-field stress regimes, ST1 and ST2, defined by the available published fault-slip data near Sizhuang by applying the separation and stress inversion TR method (TRM). The palaeostress reconstruction indicates that extension and strike-slip tectonics (i.e. transtension) affect the emplacement of the lamprophyre dikes and quartz veins. More precisely, the dike emplacement occurred under unstable stress conditions related to the shift from E–W pure extension–transtension to WNW–ESE transtension, whereas the quartz veins formed under relatively stable WNW–ESE transtension with the variant and increasing fluid pressure ( ${P_{\rm{f}}})$ giving rise to the strike-slip against dip-slip kinematics along the faults. The change from the ST1 to ST2 stress regimes reflects the significant clockwise rotation in the palaeo-Pacific plate subduction direction and defines the switching time at c. 119 Ma as precisely obtained by the lamprophyre dating.

Element geochemistry, Sr and Nd isotope, and LA-ICP-MS zircon U-Pb isotope data have been obtained for the granitoids of Dazesan pluton in the Jiaodong Peninsula, East China, and their intermediate microgranular dark enclaves so as to reveal their petrogenesis and tectonic implications. These granitoids have high SiO2 (68.25–71.56 wt.%), K2O (3.44–5.50 wt.%), total alkalis (K2O + Na2O = 7.29–9.00 wt.%), Sr (451–638 ppm), Ba (1157–2842 ppm) and light rare earth elements (LREEs) (131.57–210.08), with strong depletion both in heavy rare earth element (HREE) and high field strength element (HFSE) concentrations as well as unclearly Eu anomalies, showing typical signatures of high Ba-Sr granitoids. They possess high (La/Yb)N (32–50) and Sr/Y (50–79) values and low MgO (0.76–1.11 wt.%), Cr (9.9–19.6 ppm) and Ni (4.51–7.04 ppm) concentrations. All the above geochemical compositions are similar to those of late Early Cretaceous granitoids, in combination with zircon LA-ICP-MS U-Pb ages of 119.6 ± 1.3 to 120 ± 1 Ma for these granitoids obtained in this study, indicating c. 120 Ma probably represents the lower limit of ages when late Early Cretaceous granitoids emplaced in the Jiaodong Peninsula. The microgranular dark enclaves, forming a linear trend with their host granitoids on the oxide against SiO2 plots, display higher MgO contents of 3.05–4.39 wt.% at lower SiO2 concentrations of 54.25–56.84 wt.% and possess a zircon LA-ICP-MS U-Pb age of 119 ± 2 Ma, identical to those of these granitoids, indicating the acid magma and intermediate magma were coeval. Furthermore, dark enclaves and their host granitoids have indistinguishable (87Sr/86Sr)i values of 0.709523–0.70972 and 0.709361–0.709858, respectively, and plot within a two-liquid immiscible field on the Greig pseudoternary phase diagram. In addition, they have markedly parallel REE patterns, with the dark enclaves having much greater REE and HFSE abundances than those of their host granitoids. Therefore, it is suggested that liquid immiscibility is a viable model to explain the chemical compositional variations between the Dazeshan granitoids and their dark enclaves. Based on the element geochemistry, geochronology and Sr- and Nd-isotope of the Dazeshan granitoids and their dark enclaves, it is envisaged the crust-derived acid melts due to partial melting of ancient continental lower crust in the Jiaodong Peninsula (mainly Neoarchean-Palaeoproterozoic basement in the Jiaobei terrane) containing a subduction-related material, resulting from the addition of the enriched subcontinental lithospheric mantle-derived melts, assimilated the lithospheric mantle-derived basic melts and formed the homogeneous magma chamber at the crust base, then split into two immiscible liquids, with one granitic liquid producing the Dazeshan granitoids and the other intermediate one forming the dark enclave during its ascent. Combined with previous studies, the identification of a lithospheric mantle-derived material in the Dazeshan granitoids suggests a catastrophic lithospheric thinning at c. 120 Ma, reflecting an abrupt change in the direction of Palaeo-Pacific plate subducting and the corresponding regional tectonic transition from E–W extension to NW–SE extension.

The Linglong gold field is located in the eastern part of the Linglong magmatic core complex of Jiaodong area, which is a set of rock mass combinations with complicated genesis, multiple sources and different magmatic evolution sequences surrounded by the Jiaojia fault belt and the Zhaoyuan-Pingdu fault belt.In the ore field, The core of the complex rock mass is formed by Linglong-type gneiss-like biotite granite and Guojialing-type porphyryite-like diorite, and the upper cover is Luanjiahe-type coarse-grained monzonitc granite and a small amount of Archean metamorphic rocks.The detachment belt is developed between the Linglong-type gneiss-like biotite granite pluton and the Luanjiahe-type coarse-grained monzonitc granite pluton which was formed by the progressive deformation and transformation of the Potouqing fault belt.The Potouqing detachment belt is a steep and slow shovel-type fracture, the depth in turning end of which is between-300 m and-500 m, and the turning depth of the detachment belt towards the north and east directions is gradually deepening.In order to understand the structural evolution and mineralization characteristics of the uplift detachment belt of the Linglong magmatic core complex, the observation results of the diagenetic structure and brittle ductile deformation characteristics of granite in the later stage show that the fault structure has undergone multiple stress turns from compression shear in the early stage of mineralization to extension detachment during the mineralization period. The diagenetic age（130～125 Ma） of the Guojialing-type porphyry-like diorite in the ore field is coincided with the plastic deformation stage of the detachment belt（137～123 Ma）,and the brittle deformation stage of the detachment belt（123～108 Ma） is basically coincided with the large-scale mineralization event（125.8 ～105 Ma） of the mine, showing the significant correlation between the structural mineralization of the magmatic core complex uplift-detachment belt in the Linglong gold field and the uplift structure of the porphyry-like granodiorite of the Guojialing type.The geometric, kinematics and chronological characteristics of the magmatic core complex uplift-detachment belt of Linglong gold field demonstrate the structural ore-controlling regularity, which can be used to guide the deep prospecting of Linglong gold field.

The Wang'ershan gold deposit, located in the southern Jiaojia goldfield, is currently the largest gold deposit hosted within the subsidiary faults in Jiaodong Peninsula, with a gold reserve of >60 t gold at a grade of 4.07 g/t Au. It is hosted in the Late Jurassic Linglong biotite granites and controlled by the second-order, N- to NNE-trending Wang'ershan Fault (and its subsidiary faults) which is broadly parallel to the first-order Jiaojia Fault in the goldfield. Gold mineralization occurs as both disseminated- and stockwork-style and quartz-sulfide vein-style ores, mainly within altered cataclasites and breccias, and sericite-quartz and potassic alteration zones, respectively. Mineralization stages can be divided into (1) the pyrite-quartz-sericite stage, (2) the quartz-pyrite stage, (3) the quartz-sulfide stage, and (4) the quartz-carbonate stage.Two sericite samples associated with the main ore-stage pyrites from pyritic phyllic ores of the deposit with weighted mean plateau Ar-40/Ar-39 age of 120.7 +/- 0.6 Ma and 119.2 +/- 0.5 Ma, respectively, were selected for Ar-40/Ar-39 geochronology. On the basis of petrography and microthermometry, three types of primary fluid inclusions related to the ore forming event were identified: type 1 H2O-CO2-NaCI, type 2 aqueous, and type 3 CO2 fluid inclusions (in decreasing abundance). Stage I quartz contains all three primary fluid inclusions, while stages 2 and 3 quartz contain both type 1 and 2 inclusions, and stage 4 quartz contains only type 2 inclusions. The contemporaneous trapping, similar salinities and total homogenization temperature ranges, and different homogenization phases of type 1 and type 2 inclusions indicate that fluid immiscibility did take place in stages I, 2 and 3 ores, with P-T conditions of 190 to 85 MPa and 334 to 300 degrees C for stage 1 and 200 to 40 MPa and 288 to 230 degrees C for stages 2 and 3. Combined with the H-O-C-S-Pb isotopic compositions, ore-forming fluids may have a metamorphic-dominant mixed source, which could be associated with the dehydration and decarbonisation of a subducting paleo-Pacific plate and characterized by medium-high temperature (285350 degrees C), CO2-bearing (similar to 8 mol%) with minor CH4 (1-4% in carbonic phase), and low salinity (3.38-8.45 eq. wt.% NaCI). During mineralization, the fluid finally evolved into a medium-low temperature NaCI-H2O system. Au(HS)(2)(-) was the most probable gold-transporting complex at Wang'ershan, due to the low temperature (157-350 degrees C) and near-neutral to weakly acidic ore fluids. The reaction between gold-bearing fluids and iron bearing wall-rocks, and fluid-immiscibility processes caused via fluid-pressure cycling during seismic movement along fault zones that host lode-gold orebodies, which led to breakdown of Au(HS)(2)(-), are interpreted as the two main precipitation mechanisms of gold deposition.In general, the Wang'ershan deposit and other deposits in the Jiaojia camp have concordant structural system and wall-rock alteration assemblages, nature of orebodies and gold occurrence conditions, as well as the similar geochronology, ore-forming fluids system and stable isotope compositions. Thus gold mineralization in the Jiaojia goldfield was a large-scale unified event, with consistent timing, origin, process and mechanism. (C) 2016 Elsevier B.V. All rights reserved.

The Xincheng gold deposit, located in west Jiaodong Peninsula in southeast North China Craton, is a representative mesothermal lode deposit hosted in Late Mesozoic granitoids in Jiaodong. Gold mineralization occurs as disseminated- and stocicwork-style ores within the hydrothermal breccias and cataclastic zones controlled by the Jiaojia fault, whereas echelon tensile auriferous veins hosted in the NE- and NNE-trending subsidiary faults cutting the granitoids occur subordinately. According to crosscutting relationships and mineral paragenesis, four paragenetic stages were identified, which are pyrite-quartz-sericite (stage 1), quartz-pyrite (stage 2), quartz-polysulfide (stage 3) and quartz-carbonate (stage 4). Gold was deposited during the quartz-pyrite and quartz-polysulfide stages.On the basis of microthermometry and Raman spectroscopy on fluid inclusions contained within the quartz veins from stages 2 and 3, three types of fluid inclusions were recognized: (1) type 1 H2O-CO2 inclusions that show high temperatures (ca. 260 degrees C), low salinities (2.4-8.9 wt.% equiv. NaCl) and variable XCO2 (0.03 to 0.20), (2) type 2 aqueous inclusions with medium temperatures (ca. 220 degrees C) and low to moderate salinities (3.1-13.3 wt.% equiv. NaCl); (3) type 3 pure CO2 inclusions with a carbonic phase density of 0.712 +/- 0.03 g/cm(3). Types 1 and 2 inclusions appear in the same growth phase of the quartz grains from the breccias and tensile auriferous veins. These coexisting inclusions are likely formed by fluid immiscibility due to unmixing from a single homogeneous H2O-CO2 parent fluid at trapping P-T conditions of 221 to 304 degrees C (average 261 +/- 19 degrees C) and 780 to 2080 bar. The fluid immiscibility is interpreted to be initiated by fluid pressure decrease at ca. 300 C. The ore-fluid P-T-X conditions of the Xincheng gold deposit are the same as those for mesothermal deposits. Gold was most probably transported as a Au(HS)(-)(2) complex at Xincheng. Fluid immiscibility over the temperature interval of 221-304 degrees C resulted in significant H2S loss from the hydrothermal solution, thereby reducing Au(HS)I solubility with concomitant deposition of gold. The mineralizing process of the granitoid-hosted Xincheng lode-gold deposit is likely related to the fluid immiscibility. (C) 2014 Elsevier B.V. All rights reserved.

Acta Geologica Sinica - English EditionVolume 88, Issue s2 p. 835-836 Meeting Abstracts Hydrothermal Alteration and Gold Mineralization in the Jiaojia Gold Deposit, Jiaodong Peninsula, China Binglin ZHANG, Binglin ZHANG State Key Laboratory of Geological Process and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorLiqiang YANG, Corresponding Author Liqiang YANG State Key Laboratory of Geological Process and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaCorresponding author. E-mail: lqyang@cugb.edu.cnSearch for more papers by this authorZhongliang WANG, Zhongliang WANG State Key Laboratory of Geological Process and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorYue LIU, Yue LIU State Key Laboratory of Geological Process and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorRongxin ZHAO, Rongxin ZHAO Jiaojia Gold Company, Shandong Gold Mining Co., Ltd., Laizhou 261441 Shandong, ChinaSearch for more papers by this author Binglin ZHANG, Binglin ZHANG State Key Laboratory of Geological Process and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorLiqiang YANG, Corresponding Author Liqiang YANG State Key Laboratory of Geological Process and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaCorresponding author. E-mail: lqyang@cugb.edu.cnSearch for more papers by this authorZhongliang WANG, Zhongliang WANG State Key Laboratory of Geological Process and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorYue LIU, Yue LIU State Key Laboratory of Geological Process and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorRongxin ZHAO, Rongxin ZHAO Jiaojia Gold Company, Shandong Gold Mining Co., Ltd., Laizhou 261441 Shandong, ChinaSearch for more papers by this author First published: 29 December 2014 https://doi.org/10.1111/1755-6724.12375_76Citations: 1Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume88, Issues2Special Issue: Meeting Abstracts: The 14th Quadrennial International Association on the Genesis of Ore Deposits Symposium. August 19–22, 2014, Kunming, ChinaDecember 2014Pages 835-836 RelatedInformation

Acta Geologica Sinica - English EditionVolume 88, Issue s2 p. 1167-1168 Meeting Abstracts P-T Conditions and Mechanisms for Precipitation of Gold in the Xincheng Deposit, Jiaodong Peninsula, China Zhongliang WANG, Zhongliang WANG State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorLiqiang YANG, Corresponding Author Liqiang YANG State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaCorresponding author. E-mail: lqyang@cugb.edu.cnSearch for more papers by this authorLinnan GUO, Linnan GUO State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorYue LIU, Yue LIU State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorChao ZHANG, Chao ZHANG State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorRuihong LI, Ruihong LI State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorLiang ZHANG, Liang ZHANG State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorXiaoli ZHENG, Xiaoli ZHENG Shandong Gold Mining Stock Co., LTD, Laizhou, Shandong Province 261400 ChinaSearch for more papers by this authorRongxin ZHAO, Rongxin ZHAO Jiaojia Gold Company, Shandong Gold Mining Stock Co., LTD, Laizhou, Shandong Province 261438 ChinaSearch for more papers by this author Zhongliang WANG, Zhongliang WANG State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorLiqiang YANG, Corresponding Author Liqiang YANG State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaCorresponding author. E-mail: lqyang@cugb.edu.cnSearch for more papers by this authorLinnan GUO, Linnan GUO State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorYue LIU, Yue LIU State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorChao ZHANG, Chao ZHANG State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorRuihong LI, Ruihong LI State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorLiang ZHANG, Liang ZHANG State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083 ChinaSearch for more papers by this authorXiaoli ZHENG, Xiaoli ZHENG Shandong Gold Mining Stock Co., LTD, Laizhou, Shandong Province 261400 ChinaSearch for more papers by this authorRongxin ZHAO, Rongxin ZHAO Jiaojia Gold Company, Shandong Gold Mining Stock Co., LTD, Laizhou, Shandong Province 261438 ChinaSearch for more papers by this author First published: 29 December 2014 https://doi.org/10.1111/1755-6724.12379_52Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume88, Issues2Special Issue: Meeting Abstracts: The 14th Quadrennial International Association on the Genesis of Ore Deposits Symposium. August 19–22, 2014, Kunming, ChinaDecember 2014Pages 1167-1168 RelatedInformation

The majority of gold resources (>95%) in the Jiaodong Peninsula, the largest gold producer in China, are hosted in the Late Jurassic Linglong-type and Early Cretaceous Guojialing-type granitoids. However, the petrogenesis and sources of the granitic rocks, especially the Early Cretaceous granitoids, remain controversial. The Guojialing-type granitoid, intruding the Ling,long-type granitoid, includes six plutonic bodies from west to east through the Jiaodong Peninsula: Sanshandao, Xincheng, Shangzhuang, Beijie, Congjia and Guojialing, of which the Xincheng pluton is the only Guojialing-type granitoid that hosts the super-large gold deposit. in Jiaodong. The Xincheng pluton, intruding the Linglong biotite-granite, mainly consists of quartz monzonite and monzogranite. The boundary between the quartz monzonite and monzogranite is unclear, suggesting that they are coeval intrusions. In order to discuss the petrogenesis of the Xincheng Early Cretaceous granitoids, and reveal the geodynamics back ground for the high Ba-Sr Guojialing-type granite, this paper systematically investigated the Xincheng pluton to sample the monzogranite, and conducted the elemental, mineralogical and Sr-Nd isotopic analyse. The Xincheng monzogranites, typical high Ba-Sr granites, possess high SiO2 (70. 89% similar to 73. 35%), K2O (7. 03% similar to 8. 68%), total alkalis (K2O + Na2O = 7. 03% similar to 8. 68%), Sr (>640 x 10(-6)) Ba (> 853 x 10(-6)) and LREE (>65.43 x 10(-6)), with low HREE and HFSE contents and insignificant Eu anomalies. The rocks display markedly high Sr/Y (> 115) and (La/Yb)(N) (20. 32 similar to 198. 8) ratios. They have low Al2O3 (14. 41% similar to 15. 54%), MgO (0. 21% similar to 0. 62%), Rh (<103 x10(-6)), Th (<10.3 x10(-6)), U (<5.87 x10(-6)), Nb (<6.14 x 10(-6)), Ta (<0.599 x 10(-6)), Y (<10.3 x 10(-6)) and HREE (<5. 3 x 10(-6)). The plagioclases and K-feldsparsin the monzogranites both show the reverse zoning texture, of which the pragioclase, belong to oligoclase with An contents of 12. 87 similar to 22. 91, and the K-feldspars belong to orthoclase with Or contents of 81. 24 similar to 93.69. The monzogranites have Sr-87/Sr-86 (I-Br) and epsilon(Nd)(t) values of 0.71071 similar to 0.71172 and -21. 3 similar to -17. 1, respectively, with the two-stage Nd model ages (t(DM2)) of 2310 similar to 2648 Ma. Detailed elemental, mineralogical and Sr-Nd isotopic data suggest that the Xincheng monzogranites were most likely generated by partial melting of the basement rocks of the Jiaobei terrane with minor addition of intermediate magma which were partial melting of juvenile mafic lower crust formed by the earlier underplating of mantle magma. Their genesis is linked to asthenosphere upwelling, triggered by the subduction of the paleo-Pacific slab beneath the North China Craton.

Jiaodong Peninsula,the most important gold province in China,is an area with concentration occurrence of largesuperlarge gold deposits,the proved reserves in Jiaodong Peninsula account for nearly 1 /3 of the country's. Fracture zone altered type gold deposit is the most important deposit type which accounts for more than 90% of the proved gold reserves in Jiaodong Peninsula.Jiaojia gold deposit is named after"Jiaojia-type"fracture zone altered rock type gold deposit,large-scale sericite-quartz alteration zone( with the width of 20 ~200m) and potassic alteration zone( with the width of 50 ~300m) occur in the gold deposit. Altered rock type gold orebody mainly develops in the sericite-quartz alteration zone which is in the footwall of Jiaojia fault zone. Based on the detailed geologic observations in the field,this paper found out the alteration type and mineral assemblage of the Jiaojia gold deposit,collected different types of alteration rock samples scientifically,and conducted rock geochemistry element analysis which uses the method of the mass balance to discuss the regularity of elements migration in the hydrothermal alteration process and mechanism. Thereinto,potassic alteration occurs in the premineralization,potassic granite is usually as lumpy and breccia residual in the pyrite-sericite-quartz and sericite-quartz altered rock which is controlled by the secondary faults in the footwall of the Jiaojia fault,and the scale is controlled by the faults. The scale of sericite-quartz altered rock is the largest in the footwall of the Jiaojia fault with the width of 10 ~ 200 m,sericitequartz altered zone controlled by secondary faults is relatively small,usually presenting as wide 0. 1 ~ 1m veins in the potassic granite,which indicates sericite-quartz alteration is later than potassic alteration. Compared with biotite granite,rocks from various alteration zones show high contents of K2 O and low contents of Al2O3,CaO and Na2 O,but elements like Si,Fe,and Mg have different characteristics. Potassic granite are rich in K2 O,while both sericite-quartz altered rock and pyrite-sericite-quartz altered rock are characterized with increasements of MgO and Fe2O3. During the process of potassic alteration,SiO2 and K2O were added,indicating that the forming fluid is silicon-rich,alkaline and oxidation. In the process of alteration from potassic granite to pyrite-sericite-quartz altered rock,the Fe2O3 increased obviously,which may be caused by the decomposement of biotite and other melanocratic minerals.Furthermore,sulfophilic elements like Au,Ag,As,Pb and Zn also increased significantly. Part of the gold may be derived from Linglong biotite granite. In the process of potassic alteration,the metasomatism between the wall rock and silicon-rich,alkaline and oxidation fluids,extracted gold in the form of high valence ion from wall rocks. To be specific,dispersed reduced gold( Au0) was activated to be oxidized( Au+,Au3 +),and migrated with the fluids in the form of AuH3SiO4. In the process of sericite-quartz alteration,the descent of the content of SiO2 induced the decomposement of AuH3SiO4. Fe2 +and Fe3 +were consumed to form the pyrites,which induced the deposition and enrichment of gold. Gold activate,migrate and deposit run through all these process.