Tritium （3^H） in excess of the atmospheric values was found at volcanic Lakes Pavin （France）, Laacher （Germany） and Nemrut （Turkey）, as well as Kilauea Volcano at Hawaii （USA） and other volcanoes. Because 3^...Tritium （3^H） in excess of the atmospheric values was found at volcanic Lakes Pavin （France）, Laacher （Germany） and Nemrut （Turkey）, as well as Kilauea Volcano at Hawaii （USA） and other volcanoes. Because 3^H has a short half-life of 12.3 years, the tritium and the resulting 3^He must have formed recently in the Earth. The result suggests that nuclear reactions may generate a significant amount of tritium in the interior of the Earth, although we have not yet learned what the reaction mechanism may be responsible. The nuclear reaction that can be responsible for tritium production in the Earth is probably a new research field in physics science. Nuclear reactions that generate tritium might be a source of ＂missing＂ energy （heat） in the interior of the Earth. Finding in-situ 3^H in the mantle may exhibit an alternative explanation of 3^He origin in the deep Earth.展开更多
In this paper a comprehensive tracing study is conducted on mantle degassing and deep-seated geological structures in different types of fault zones in the continent of China based on the helium isotope data, coupled ...In this paper a comprehensive tracing study is conducted on mantle degassing and deep-seated geological structures in different types of fault zones in the continent of China based on the helium isotope data, coupled with some indices such as CO2/3He, CH4/3He and 40Ar/36Ar, and geological tectonics data. There are four representative types of fault zones: (1) Lithospheric fault zones in the extensional tectonic environment are characterized by a small Earth’s crust thickness, a lower CH4/3He-high R and lower CO2/3He-high R system, the strongest mantle de- gassing, and the dominance of mantle fluid, as is represented by the Tancheng-Lujiang fault zone. (2) The lithospheric fault zones or the subduction zone in the strongly compresso-tectonic envi- ronment, for instance, the Bangonghu-Nujiang fault zone, are characterized by a huge thick Earth’s crust, with the R/Ra values within the range of 0.43―1.13, and weak mantle degassing with mantle-source helium accounting for 5%―14% of the total. (3) The deep-seated fault zones at the basinal margins of an orogenic belt are characterized by R values being on order of mag- nitude of 10?7, and the CH4/3He values, 109―1010, CO2/3He values, 106―108; as well as much weak mantle degassing. (4) The crustal fault zones in the orogenic belt, such as the Yaojie fault zone (F19), possess a high CH4/3He-low R (10?8) and high CO2/3He-low R system, with no obvi- ous sign of mantle degassing. Studies have shown that the deep-seated huge fault zones are the major channel ways for mantle degassing, the main factors controlling the intensity of mantle degassing are fault depth, tectonic environment and crust thickness; the intensity of mantle de- gassing can reflect the depth and the status of deep-seated tectonic environment of fault, while the geochemical tracing studies of gases can open up a new research approach; upwelling ac- tivity of hydrothermal fluids from the deep interior of the Earth may be one of the driving forces for the formation and evolution of the huge deep 展开更多
Changkeng Au-Ag deposit is a newly-discovered new type precious metal deposit. N2-Ar-He systematics studies and 3He/4He and δD-δ180 composition analyses show that the ore-forming fluid of the deposit is composed mai...Changkeng Au-Ag deposit is a newly-discovered new type precious metal deposit. N2-Ar-He systematics studies and 3He/4He and δD-δ180 composition analyses show that the ore-forming fluid of the deposit is composed mainly of formation water (sedimentary brine) but not of meteoric water, which was thought to be source of the ore-forming fluid by most previous researchers. The content of mantle-derived magmatic water in the ore-forming fluid is quite low, usually lower than 10% . According to the source of the ore-forming fluid, the Changkeng Au-Ag deposit should belong to sedimentary brine transformed deposits. From the Late Jurassic to the Early Cretaceous Period, with deposition and accumulation of thick sediments in Sanzhou Basin, the formation water in the sedimentary layers was expelled from the basin because of overburden pressure and increasing temperature. The expelled fluid moved laterally along sedimentary layers to the margin of the basin, and finally moved upward along a gently-dipping interlayer fault. Because of a decline in pressure and temperature, ore minerals were deposited in the fault.展开更多
Along both sides of the Tancheng-Lujiang Fracture Zone in eastern China, a series of mantle source gas pools constitute a massive-scale tectonic accumulation zone in NNE direction, with the mantle geochemical characte...Along both sides of the Tancheng-Lujiang Fracture Zone in eastern China, a series of mantle source gas pools constitute a massive-scale tectonic accumulation zone in NNE direction, with the mantle geochemical characteristics of high concentrations of CO2 and He, high 3He/4He-40Ar/36Ar ratio system and high δ13Coo2 ratios (the mainfrequency, -3.4‰-4.6‰), showing no difference from the tectonic framework of the area. In the area, thetectonic environment is a rift formed as a result of diapiric mantle injection and crust thinning to form graben-type basins and lithospheric fractures. The mantle-derived volcanic rocks and inclusions are well-developed and a high geothermal zone (mantlesource) exists in the area. The characteristics of the three components (solid, liquid and gas) of mantle, concentrated all over the same tectonic space zone, show that the rift system is of a good tectonic environment or passage for mantle degassing and gas migration. The main types of the gas pools are volcano, fault-block, anticline, buried hill and so on, but most of them are combination traps closely related with fracture. For the mantle source gas pools, rift is an optimum tectonic region, and nearby lithospheric fracture, mantle source volcanic rocks or basement uplifts are a favourable structural location when reservoir-caprock association develops.展开更多
Thermal karst groundwaters with temperatures ranging from 32.8 to 62.5 ℃ were found at Taiyuan（太原） City,the capital of Shanxi（山西） Province.To identify the origin of the thermal groundwater,the following trace...Thermal karst groundwaters with temperatures ranging from 32.8 to 62.5 ℃ were found at Taiyuan（太原） City,the capital of Shanxi（山西） Province.To identify the origin of the thermal groundwater,the following tracers were used in this study：δD,δ18O,4He,3He/4He,and major chemical constituents in water.Hydrochemical and isotopic data indicate that the thermal groundwaters in the basin area are a mixture of thermal waters from the West Mountain and those from the East Mountain.Furthermore,the 4He and 4Heexc concentrations of the thermal groundwater samples are usually lower than those of the cold groundwater samples,and there is an evidently negative correlation between the temperature and the 4He concentration in thermal groundwaters from the West Mountain and the ba-sin,which means that with the increase in temperature,the He concentration increases in the vapor phase and decreases in the aqueous phase.In the plot of 3He/4He vs.4He/20Ne of all water samples：air,crust,and mantle,all thermal groundwater samples are distributed near the line between the point of air and that of crust,suggesting that atmospheric and crustal helium is the main source for that in thermal groundwaters.In other words,there are no mantle-derived fluids mixed in the thermal groundwaters.展开更多
CO2-rich cold springs occur near the active volcanoes at Wudalianchi （五大连池）, Northeast China. The springs are rich in CO2, with HCO3-as the predominant anion and have elevated contents of total dissolved solid ...CO2-rich cold springs occur near the active volcanoes at Wudalianchi （五大连池）, Northeast China. The springs are rich in CO2, with HCO3-as the predominant anion and have elevated contents of total dissolved solid （TDS） （〉1 000 mg/L）, Fe^2＋ （〉20 mg/L）, Sr （〉1 mg/L）, and dissolved Si （〉20 mg/L）. The compositions of escaped and dissolved gases of the springs are similar. The δ^13C values of escaped gases and dissolved gases in mineral springs at Wudalianchi vary from -8.77‰ to -4.53‰ and -8.24‰ to -5.26‰, while δ^18O values vary from -10.68‰ to -7.65‰ and -10.30‰ to -8.84‰, respectively, indicating the same upper mantle origin of CO2 of escaped gases and dissolved gases in the springs. Carbon and oxygen isotope fractionations and water-CO2 exchange were weak in the process of groundwater flow. The 4He content exceeds 5 000×10-6 cm^3·STP/mL in escaped gases of the mineral springs, and the 3He/4He ratios of the escaped and dissolved gases vary from 2.64Ra to 3.87Ra and 1.18Ra to 3.30Ra, respectively. It can be postulated that the CO2 of mineral springs deriving from the magma chamber of the upper mantle moves upward to the surface, to increase the content of 4He in the mineral springs and decrease the ratio of 3He/4He. The helium origin of escaped gases in springs can be calculated with the MORB-crust mixing model, but that in the north spring can be better explained with the MORB-crust-air mixing model due to the effect of mixing with surface water. However, dissolved helium in springs, except the north spring, is better explained with the MORB-crust-ASW mixing model.展开更多
Existence and regularity of solutions to model for liquid mixture of 3He-4He is considered in this paper. First, it is proved that this system possesses a unique global weak solution in H^1 （Ω, C ×R） by using ...Existence and regularity of solutions to model for liquid mixture of 3He-4He is considered in this paper. First, it is proved that this system possesses a unique global weak solution in H^1 （Ω, C ×R） by using Galerkin method. Secondly, by using an iteration procedure, regularity estimates for the linear semigroups, it is proved that the model for liquid mixture of 3He-4He has a unique solution in H^k（Ω, C × R） for all k ≥ 1.展开更多
基金supported by President Foundation of the China Institute of Atomic Energy (No.YZ-0704)
文摘Tritium （3^H） in excess of the atmospheric values was found at volcanic Lakes Pavin （France）, Laacher （Germany） and Nemrut （Turkey）, as well as Kilauea Volcano at Hawaii （USA） and other volcanoes. Because 3^H has a short half-life of 12.3 years, the tritium and the resulting 3^He must have formed recently in the Earth. The result suggests that nuclear reactions may generate a significant amount of tritium in the interior of the Earth, although we have not yet learned what the reaction mechanism may be responsible. The nuclear reaction that can be responsible for tritium production in the Earth is probably a new research field in physics science. Nuclear reactions that generate tritium might be a source of ＂missing＂ energy （heat） in the interior of the Earth. Finding in-situ 3^H in the mantle may exhibit an alternative explanation of 3^He origin in the deep Earth.
基金the State "973" Program(Grant No.G2002CB211701) the National Natural Science Foundation of China(Grant No.40372065).
文摘In this paper a comprehensive tracing study is conducted on mantle degassing and deep-seated geological structures in different types of fault zones in the continent of China based on the helium isotope data, coupled with some indices such as CO2/3He, CH4/3He and 40Ar/36Ar, and geological tectonics data. There are four representative types of fault zones: (1) Lithospheric fault zones in the extensional tectonic environment are characterized by a small Earth’s crust thickness, a lower CH4/3He-high R and lower CO2/3He-high R system, the strongest mantle de- gassing, and the dominance of mantle fluid, as is represented by the Tancheng-Lujiang fault zone. (2) The lithospheric fault zones or the subduction zone in the strongly compresso-tectonic envi- ronment, for instance, the Bangonghu-Nujiang fault zone, are characterized by a huge thick Earth’s crust, with the R/Ra values within the range of 0.43―1.13, and weak mantle degassing with mantle-source helium accounting for 5%―14% of the total. (3) The deep-seated fault zones at the basinal margins of an orogenic belt are characterized by R values being on order of mag- nitude of 10?7, and the CH4/3He values, 109―1010, CO2/3He values, 106―108; as well as much weak mantle degassing. (4) The crustal fault zones in the orogenic belt, such as the Yaojie fault zone (F19), possess a high CH4/3He-low R (10?8) and high CO2/3He-low R system, with no obvi- ous sign of mantle degassing. Studies have shown that the deep-seated huge fault zones are the major channel ways for mantle degassing, the main factors controlling the intensity of mantle degassing are fault depth, tectonic environment and crust thickness; the intensity of mantle de- gassing can reflect the depth and the status of deep-seated tectonic environment of fault, while the geochemical tracing studies of gases can open up a new research approach; upwelling ac- tivity of hydrothermal fluids from the deep interior of the Earth may be one of the driving forces for the formation and evolution of the huge deep
基金Project supported by the National Natural Science Foundation of China (Grant No. 49502029)the Natural Science Foundation of Zhongshan University Research Foundation of National Key Laboratory of Metallogenesis in Nanjing University (Grant No. 039
文摘Changkeng Au-Ag deposit is a newly-discovered new type precious metal deposit. N2-Ar-He systematics studies and 3He/4He and δD-δ180 composition analyses show that the ore-forming fluid of the deposit is composed mainly of formation water (sedimentary brine) but not of meteoric water, which was thought to be source of the ore-forming fluid by most previous researchers. The content of mantle-derived magmatic water in the ore-forming fluid is quite low, usually lower than 10% . According to the source of the ore-forming fluid, the Changkeng Au-Ag deposit should belong to sedimentary brine transformed deposits. From the Late Jurassic to the Early Cretaceous Period, with deposition and accumulation of thick sediments in Sanzhou Basin, the formation water in the sedimentary layers was expelled from the basin because of overburden pressure and increasing temperature. The expelled fluid moved laterally along sedimentary layers to the margin of the basin, and finally moved upward along a gently-dipping interlayer fault. Because of a decline in pressure and temperature, ore minerals were deposited in the fault.
文摘Along both sides of the Tancheng-Lujiang Fracture Zone in eastern China, a series of mantle source gas pools constitute a massive-scale tectonic accumulation zone in NNE direction, with the mantle geochemical characteristics of high concentrations of CO2 and He, high 3He/4He-40Ar/36Ar ratio system and high δ13Coo2 ratios (the mainfrequency, -3.4‰-4.6‰), showing no difference from the tectonic framework of the area. In the area, thetectonic environment is a rift formed as a result of diapiric mantle injection and crust thinning to form graben-type basins and lithospheric fractures. The mantle-derived volcanic rocks and inclusions are well-developed and a high geothermal zone (mantlesource) exists in the area. The characteristics of the three components (solid, liquid and gas) of mantle, concentrated all over the same tectonic space zone, show that the rift system is of a good tectonic environment or passage for mantle degassing and gas migration. The main types of the gas pools are volcano, fault-block, anticline, buried hill and so on, but most of them are combination traps closely related with fracture. For the mantle source gas pools, rift is an optimum tectonic region, and nearby lithospheric fracture, mantle source volcanic rocks or basement uplifts are a favourable structural location when reservoir-caprock association develops.
基金supported by the National Natural Science Foundation of China (Nos. 40872157 and 40830748)the China-Russia International Cooperation and Exchange Project of NSFC-RFBR (No. 40711120189)+1 种基金Program for New Century Excellent Talents in University (No. NCET-07-0773)the Aid Project of the Ministry of Science and Technology of China to Developing Countries (No. 2008041012)
文摘Thermal karst groundwaters with temperatures ranging from 32.8 to 62.5 ℃ were found at Taiyuan（太原） City,the capital of Shanxi（山西） Province.To identify the origin of the thermal groundwater,the following tracers were used in this study：δD,δ18O,4He,3He/4He,and major chemical constituents in water.Hydrochemical and isotopic data indicate that the thermal groundwaters in the basin area are a mixture of thermal waters from the West Mountain and those from the East Mountain.Furthermore,the 4He and 4Heexc concentrations of the thermal groundwater samples are usually lower than those of the cold groundwater samples,and there is an evidently negative correlation between the temperature and the 4He concentration in thermal groundwaters from the West Mountain and the ba-sin,which means that with the increase in temperature,the He concentration increases in the vapor phase and decreases in the aqueous phase.In the plot of 3He/4He vs.4He/20Ne of all water samples：air,crust,and mantle,all thermal groundwater samples are distributed near the line between the point of air and that of crust,suggesting that atmospheric and crustal helium is the main source for that in thermal groundwaters.In other words,there are no mantle-derived fluids mixed in the thermal groundwaters.
基金supported by the National Natural Science Foundation of China(Nos.40425001,40602031,40830748),and Russian Fund for Basic Research
文摘CO2-rich cold springs occur near the active volcanoes at Wudalianchi （五大连池）, Northeast China. The springs are rich in CO2, with HCO3-as the predominant anion and have elevated contents of total dissolved solid （TDS） （〉1 000 mg/L）, Fe^2＋ （〉20 mg/L）, Sr （〉1 mg/L）, and dissolved Si （〉20 mg/L）. The compositions of escaped and dissolved gases of the springs are similar. The δ^13C values of escaped gases and dissolved gases in mineral springs at Wudalianchi vary from -8.77‰ to -4.53‰ and -8.24‰ to -5.26‰, while δ^18O values vary from -10.68‰ to -7.65‰ and -10.30‰ to -8.84‰, respectively, indicating the same upper mantle origin of CO2 of escaped gases and dissolved gases in the springs. Carbon and oxygen isotope fractionations and water-CO2 exchange were weak in the process of groundwater flow. The 4He content exceeds 5 000×10-6 cm^3·STP/mL in escaped gases of the mineral springs, and the 3He/4He ratios of the escaped and dissolved gases vary from 2.64Ra to 3.87Ra and 1.18Ra to 3.30Ra, respectively. It can be postulated that the CO2 of mineral springs deriving from the magma chamber of the upper mantle moves upward to the surface, to increase the content of 4He in the mineral springs and decrease the ratio of 3He/4He. The helium origin of escaped gases in springs can be calculated with the MORB-crust mixing model, but that in the north spring can be better explained with the MORB-crust-air mixing model due to the effect of mixing with surface water. However, dissolved helium in springs, except the north spring, is better explained with the MORB-crust-ASW mixing model.
基金Sponsored by the National Natural Science Foundation of China(11071177)NSF of Sichuan Science and Technology Department of China(2010JY0057)the NSF of Sichuan Education Department of China(11ZA102)
文摘Existence and regularity of solutions to model for liquid mixture of 3He-4He is considered in this paper. First, it is proved that this system possesses a unique global weak solution in H^1 （Ω, C ×R） by using Galerkin method. Secondly, by using an iteration procedure, regularity estimates for the linear semigroups, it is proved that the model for liquid mixture of 3He-4He has a unique solution in H^k（Ω, C × R） for all k ≥ 1.
