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The deposit's geological setting, stable isotopes, fluid inclusions and geochemistry are studied. It is concluded that the ore-forming hydrothermal solutions were high-temperature magmatic fluids, although the involvement of crustal materials cannot be ruled out. It is proposed that the deposit formed in a calc-alkaline series environment at an active continental margin., The deposit's geological setting, stable isotopes, fluid inclusions and geochemistry are studied. It is concluded that the ore-forming hydrothermal solutions were high-temperature magmatic fluids, although the involvement of crustal materials cannot be ruled out. It is proposed that the deposit formed in a calc-alkaline series environment at an active continental margin.

In the eastern part of China, large-scale gold mineralisation during the Mesozoic resulted in many important areas of gold ore concentration. Isotope data are selected from four previously studied deposits and two analysed for the first time, all of them representative quartz vein deposits from six important areas of gold concentration on the periphery of the North China platform: Jiaodong, Dandong, Huadian, Jidong, Xiaoqinling and Zhangjiakou. The deposits' metallogenic ages were determined using the Ludwig method. The results confirmed that all six representative deposits were formed during the Mesozoic. Rb-Sr ages were around 123.6 Ma for Linglong, 112.2 Ma for Wulong, 246 Ma for Jiapigou, 120 Ma for Jinchangyu, 168.2 Ma for Xiaoqinling and 96.9 Ma for Dongping. The time gaps between the gold deposits and their surrounding granites ranged from 14.1 m.y at Wulong to 230.5 m.y. at Dongping., In the eastern part of China, large-scale gold mineralisation during the Mesozoic resulted in many important areas of gold ore concentration. Isotope data are selected from four previously studied deposits and two analysed for the first time, all of them representative quartz vein deposits from six important areas of gold concentration on the periphery of the North China platform: Jiaodong, Dandong, Huadian, Jidong, Xiaoqinling and Zhangjiakou. The deposits' metallogenic ages were determined using the Ludwig method. The results confirmed that all six representative deposits were formed during the Mesozoic. Rb-Sr ages were around 123.6 Ma for Linglong, 112.2 Ma for Wulong, 246 Ma for Jiapigou, 120 Ma for Jinchangyu, 168.2 Ma for Xiaoqinling and 96.9 Ma for Dongping. The time gaps between the gold deposits and their surrounding granites ranged from 14.1 m.y at Wulong to 230.5 m.y. at Dongping.

In studying ore-forming mechanisms, it is very important to define the type and composition of the metallogenic fluid in terms of H and O isotope data. For the oldest rocks, the method of distinguishing metallogenic fluid sources by comparing the deltaD-delta18O diagram with standard values is not valid when the H and O isotope values are plotted between the meteoric water line and the magmatic water area. Isotope values for the Shuijingtun, Xiaoyingpan, Dongping, Zhongshangou and Jinjiazhuang deposits in Hebei, which are hosted by Archaean amphibolite- to granulite-facies rocks and an alkaline complex, are used to determine the sources of the metallogenic fluids. Water/rock ratios for the five deposits are presented and the principle of water/rock exchange discussed., In studying ore-forming mechanisms, it is very important to define the type and composition of the metallogenic fluid in terms of H and O isotope data. For the oldest rocks, the method of distinguishing metallogenic fluid sources by comparing the deltaD-delta18O diagram with standard values is not valid when the H and O isotope values are plotted between the meteoric water line and the magmatic water area. Isotope values for the Shuijingtun, Xiaoyingpan, Dongping, Zhongshangou and Jinjiazhuang deposits in Hebei, which are hosted by Archaean amphibolite- to granulite-facies rocks and an alkaline complex, are used to determine the sources of the metallogenic fluids. Water/rock ratios for the five deposits are presented and the principle of water/rock exchange discussed.

At the Shibangou gold deposit in Henan, the increase in volume of altered rocks in the shear zone can clearly be seen: the stronger the alteration, the greater the dilation. The rock volume of the mylonites has been lost from the non-metallogenic section, with the highest volume lost from the central mylonite zone. Mobile components such as SiO2, K2O and Na2O tend to have been increased by alteration in the mineralised sector of the shear zone and to have migrated from the non-metallogenic section during mylonitisation. These tendencies are most evident in the strongly altered and strongly mylonitised sections. Because of differences in local stress and in physical and chemical conditions in the shear zone, the fluid-rock ratio in the mylonite section was higher than in the altered section. Also important were stress relative to flow rate and quantity of fluid. Enrichment and depletion of major and trace elements in the shear zone was a combined result of their transport by fluids and of rock volume loss or gain., At the Shibangou gold deposit in Henan, the increase in volume of altered rocks in the shear zone can clearly be seen: the stronger the alteration, the greater the dilation. The rock volume of the mylonites has been lost from the non-metallogenic section, with the highest volume lost from the central mylonite zone. Mobile components such as SiO2, K2O and Na2O tend to have been increased by alteration in the mineralised sector of the shear zone and to have migrated from the non-metallogenic section during mylonitisation. These tendencies are most evident in the strongly altered and strongly mylonitised sections. Because of differences in local stress and in physical and chemical conditions in the shear zone, the fluid-rock ratio in the mylonite section was higher than in the altered section. Also important were stress relative to flow rate and quantity of fluid. Enrichment and depletion of major and trace elements in the shear zone was a combined result of their transport by fluids and of rock volume loss or gain.

Variations in local chemical, fluidic, mechanical and thermal processes in a shear zone result in local metallogenic differences. Samples of altered rocks from metallogenic areas and mylonites from non-metallogenic sections of a shear zone have been collected in the area around the Shibangou gold deposit, Henan. Studies of fluid/rock interactions and petrological mass balance have shown that the petrological volume of altered rocks in the metallogenic section has increased, whereas that in mylonites has decreased. Major elements are always enriched in the altered rocks and depleted in the mylonites. The fluid/rock ratio of the mylonites is greater than that of the altered rocks. It is thought that the enrichment and loss of major and trace elements from rocks in the shear zone are the result of processes of in- and out-flow of percolating fluids and loss and increase in rock volume., Variations in local chemical, fluidic, mechanical and thermal processes in a shear zone result in local metallogenic differences. Samples of altered rocks from metallogenic areas and mylonites from non-metallogenic sections of a shear zone have been collected in the area around the Shibangou gold deposit, Henan. Studies of fluid/rock interactions and petrological mass balance have shown that the petrological volume of altered rocks in the metallogenic section has increased, whereas that in mylonites has decreased. Major elements are always enriched in the altered rocks and depleted in the mylonites. The fluid/rock ratio of the mylonites is greater than that of the altered rocks. It is thought that the enrichment and loss of major and trace elements from rocks in the shear zone are the result of processes of in- and out-flow of percolating fluids and loss and increase in rock volume.