We have analyzed the gold content of 65 samples of mantle-derived xenoliths and their host rocks from eastern China, which is found to be inhomogeneous, falling in the ranges of 1.0×109-8.2×109 (averaging 3....We have analyzed the gold content of 65 samples of mantle-derived xenoliths and their host rocks from eastern China, which is found to be inhomogeneous, falling in the ranges of 1.0×109-8.2×109 (averaging 3.8 ×10-9) and 0.2×10-9-5.3×10-9 (averaging 2.7×10-9) in the mantle-derived xenoliths and the host basalts respectively. Except the samples from Wanquan County of Hebei Province and Anding County of Hainan Province, the gold content is the highest on the margins of the North China platform and decreases spatially towards the north and south, and temporally the samples of the Tertiary have a higher gold content than those of the Quaternary. The gold content of the mantle-derived xenoliths and the host Paleozoic kimberlites is 3.8×10-9-180×109and 0.1×10-9-38.0×10-9 respectively, which are higher than that in the mantle-derived xenoliths in basalt and the host Cenozoic basalts. The mantle-derived xenoliths have a higher gold content than the host rocks, but their relativity is not very clear, suggesting that the genetic relationship between them is complex. Our data indicate that the average gold content of the lithospheric mantle in eastern China is approximately equal to or approaching 3.8×10-9, which is lower than the average abundance of the upper mantle (5.0×10-9), higher than the average abundance of the continental crust (3.0×10-9) and only slightly higher than the average abundance of the lower continental crust (3.4×10-9). Except the samples from Hainan Province, the mantle-derived xenoliths in basalts with a high gold content are distributed on the two margins of the North China platform, corresponding to the gold deposits-concentrated districts in northwest Hebei Province and Shandong Province, showing the control by the old continental lithospheric mantle and the lower continental crust on the margins of the North China platform. The gold content of the mantle-derived xenoliths from Hainan Province ranges from 7.1×10-9 to 15×10-9, suggesting that some blocks of the lithospheric mantle in Hainan Province may be derived from the ancient gold-rich lithospheric mantle of western Australia and that Hainan Province may possibly be an important gold deposits-concentrated district. Some mantle-derived xenoliths in kimberlite of Shandong Province have an excessively high gold content amounting to 180×10-9, which provides new evidence for the possibility of 'finding gold deposits near kimberlite pipes or alkali-basalt volcanic vents'. Thererfore, the gold content of the mantle-derived xenoliths may be an indicator to the distribution of gold deposits-concentrated districts.展开更多
On the contiguous territories of southeastern Russia and northeastern China,many gold-bearing areas are conjugate in space with the gradient zones of the gravity field.Large gold-ore districts,defining in many respect...On the contiguous territories of southeastern Russia and northeastern China,many gold-bearing areas are conjugate in space with the gradient zones of the gravity field.Large gold-ore districts,defining in many respects the metallogenic signature of the region,are located on the joints of differently oriented gradient zones.In the best-studied districts,the Precambrian protrusions,staged distribution of magmatic chambers (by vertical) above the Mohorovicic discontinuity and restriction to the peripheral parts of intrusive massifs have been recognized.Different-type gold deposits in the studied ore-placer districts and nodes are often located on the areas of joint of the granitoid massifs and subvolcanic bodies with depressions.Availability of areals of metasomatic alterations of rocks,placers,and ore occurrences of precious metals on such but poorly studied areas can serve as the basis for the revision and detailed forecasting-prospecting works to develop the mineral-raw material base of the region for precious metals.展开更多
The gold contents of 59 samples of mantle-derived xenoliths, along with 85 samples of sulfide assemblages in them, of Cenozoic basalt from eight districts in eastern China are analyzed. The gold contents of mantle xen...The gold contents of 59 samples of mantle-derived xenoliths, along with 85 samples of sulfide assemblages in them, of Cenozoic basalt from eight districts in eastern China are analyzed. The gold contents of mantle xenoliths usually fall in the range of 10展开更多
The gold sulfide concentrate with a high As content in Liangshan District, Sichuan Province, China, is a potentially important resource. This paper describes experiments of dearsenification of gold concentrate in a we...The gold sulfide concentrate with a high As content in Liangshan District, Sichuan Province, China, is a potentially important resource. This paper describes experiments of dearsenification of gold concentrate in a weakly reduced atmosphere in a rotary pipe furnace. The results showed that the optimal parameters were a temperature range of 650-700℃, 15%-16% CO2 of gas and a reaction time of 30-40 min. The removal rate of arsenic and sulfur was over 95% and 25%-28%, respectively. With further oxidization and roasting, residue sulfur in the roasted materials was dropped to below 4%, and the cyanide leaching recovery of gold was over 92%.展开更多
基金supported by the National Natural Science Foundation of China grant 49972034the National 973 Project of China grant G1999043211
文摘We have analyzed the gold content of 65 samples of mantle-derived xenoliths and their host rocks from eastern China, which is found to be inhomogeneous, falling in the ranges of 1.0×109-8.2×109 (averaging 3.8 ×10-9) and 0.2×10-9-5.3×10-9 (averaging 2.7×10-9) in the mantle-derived xenoliths and the host basalts respectively. Except the samples from Wanquan County of Hebei Province and Anding County of Hainan Province, the gold content is the highest on the margins of the North China platform and decreases spatially towards the north and south, and temporally the samples of the Tertiary have a higher gold content than those of the Quaternary. The gold content of the mantle-derived xenoliths and the host Paleozoic kimberlites is 3.8×10-9-180×109and 0.1×10-9-38.0×10-9 respectively, which are higher than that in the mantle-derived xenoliths in basalt and the host Cenozoic basalts. The mantle-derived xenoliths have a higher gold content than the host rocks, but their relativity is not very clear, suggesting that the genetic relationship between them is complex. Our data indicate that the average gold content of the lithospheric mantle in eastern China is approximately equal to or approaching 3.8×10-9, which is lower than the average abundance of the upper mantle (5.0×10-9), higher than the average abundance of the continental crust (3.0×10-9) and only slightly higher than the average abundance of the lower continental crust (3.4×10-9). Except the samples from Hainan Province, the mantle-derived xenoliths in basalts with a high gold content are distributed on the two margins of the North China platform, corresponding to the gold deposits-concentrated districts in northwest Hebei Province and Shandong Province, showing the control by the old continental lithospheric mantle and the lower continental crust on the margins of the North China platform. The gold content of the mantle-derived xenoliths from Hainan Province ranges from 7.1×10-9 to 15×10-9, suggesting that some blocks of the lithospheric mantle in Hainan Province may be derived from the ancient gold-rich lithospheric mantle of western Australia and that Hainan Province may possibly be an important gold deposits-concentrated district. Some mantle-derived xenoliths in kimberlite of Shandong Province have an excessively high gold content amounting to 180×10-9, which provides new evidence for the possibility of 'finding gold deposits near kimberlite pipes or alkali-basalt volcanic vents'. Thererfore, the gold content of the mantle-derived xenoliths may be an indicator to the distribution of gold deposits-concentrated districts.
基金financial support of the Presidium of RAS and FEB of RAS(project 09-I-П-06)Geological Survey of China (Project 1212010786005)
文摘On the contiguous territories of southeastern Russia and northeastern China,many gold-bearing areas are conjugate in space with the gradient zones of the gravity field.Large gold-ore districts,defining in many respects the metallogenic signature of the region,are located on the joints of differently oriented gradient zones.In the best-studied districts,the Precambrian protrusions,staged distribution of magmatic chambers (by vertical) above the Mohorovicic discontinuity and restriction to the peripheral parts of intrusive massifs have been recognized.Different-type gold deposits in the studied ore-placer districts and nodes are often located on the areas of joint of the granitoid massifs and subvolcanic bodies with depressions.Availability of areals of metasomatic alterations of rocks,placers,and ore occurrences of precious metals on such but poorly studied areas can serve as the basis for the revision and detailed forecasting-prospecting works to develop the mineral-raw material base of the region for precious metals.
基金the National Natural Science Foundation of China (Grant No. 40372052)the Natural Science Foundation of Shaanxi Province (Grant No. 2004B27)
文摘The gold contents of 59 samples of mantle-derived xenoliths, along with 85 samples of sulfide assemblages in them, of Cenozoic basalt from eight districts in eastern China are analyzed. The gold contents of mantle xenoliths usually fall in the range of 10
文摘The gold sulfide concentrate with a high As content in Liangshan District, Sichuan Province, China, is a potentially important resource. This paper describes experiments of dearsenification of gold concentrate in a weakly reduced atmosphere in a rotary pipe furnace. The results showed that the optimal parameters were a temperature range of 650-700℃, 15%-16% CO2 of gas and a reaction time of 30-40 min. The removal rate of arsenic and sulfur was over 95% and 25%-28%, respectively. With further oxidization and roasting, residue sulfur in the roasted materials was dropped to below 4%, and the cyanide leaching recovery of gold was over 92%.
