The concentration, distribution, and occurrence of rare earth elements (REEs) in coals as well as stone coalsin different geological periods from Chongqing were studied. The results show that the REE content in coals ...The concentration, distribution, and occurrence of rare earth elements (REEs) in coals as well as stone coalsin different geological periods from Chongqing were studied. The results show that the REE content in coals fromChongqing is much higher than that of the ordinary Chinese coals, the Late Paleozoic coals from North China, UScoals, and the world coals. Although the concentration of light rare earth elements (LREE) is higher than that of heavyrare earth elements (HREE), the ratio of LREE to HREE is as low as 5.11. The REE content decreases with thecoal-formation periods from old to new. The REE content in the Sinian stone coal is the highest, but it is the lowest inEarly Jurassic coals. The similar REE contents in bituminous coals and anthracite show that the metamorphism has alittle influence on REE content in coal. In addition, silicate association dominates the occurrence mode of REEs incoals from Chongqing.展开更多
A severe Asian Dust Storm(ADS)event occurred on April 16-17th,2006 in northem China.Mineral components of dust samples were analyzed using X-ray diffraction(XRD).The result indicates that dust particles were dominated...A severe Asian Dust Storm(ADS)event occurred on April 16-17th,2006 in northem China.Mineral components of dust samples were analyzed using X-ray diffraction(XRD).The result indicates that dust particles were dominated by quartz(37.4%)and clay(32.9%),followed by plagioclase(13.7%),with small amounts of calcite,K-feldspar,dolomite,homblende,and gypsum(all【10%).展开更多
This paper analyses the sequence stratigraphy and palaeogeography of the Early and early Middle Jurassic coal measures in the Turpan-Hami Basin,northwestern China.The controls of the palaeogeography and sequence strat...This paper analyses the sequence stratigraphy and palaeogeography of the Early and early Middle Jurassic coal measures in the Turpan-Hami Basin,northwestern China.The controls of the palaeogeography and sequence stratigraphy on the coal accumulation in this basin have been discussed.The results show that the coal measures were formed in a fluvial-delta-lacustrine sedimentary system,and a total of 4 third-order sequences were developed.展开更多
The northern type Longtan Formation of the Late Permian in central Hunan is dominated by an assemblage of greyish black mudstone,siltstone,sandy mudstone,fine sandstone and coals,and contains a variety of sedimentary ...The northern type Longtan Formation of the Late Permian in central Hunan is dominated by an assemblage of greyish black mudstone,siltstone,sandy mudstone,fine sandstone and coals,and contains a variety of sedimentary structures such as thin sandstone-mudstone interbedded bedding,flaser beddings,lenticular beddings.展开更多
The Qinshui Basin in southeastern Shanxi Province is an important base for coalbed methane exploration and production in China.The methane reservoirs in this area are the Carboniferous and Permian coals and their thic...The Qinshui Basin in southeastern Shanxi Province is an important base for coalbed methane exploration and production in China.The methane reservoirs in this area are the Carboniferous and Permian coals and their thickness are strongly controlled by the depositional environments and the sequence stratigraphic framework.This paper analyzes the high-resolution sequence stratigraphy of the Permo-Carbo-niferous Taiyuan and Shanxi Formations.展开更多
In this paper, an experimental study was conducted in order to test the feasibility of sintering mullite directly from the high-alumina fly ash, without adding any extra material. The results show that the mullite con...In this paper, an experimental study was conducted in order to test the feasibility of sintering mullite directly from the high-alumina fly ash, without adding any extra material. The results show that the mullite contents in most sintered samples are over 70%. The samples sintered from the beneficiated fly ash have a higher content of mullite than those from the as-received fly ash under the same synthetic conditions. To obtain an equal amount of mullite, a higher sintering temperature is needed for the beneficiated fly ash than for the as-received fly ash. Considering the physical properties of sintered mullite, the favorable sintering temperature is 1400℃ for the as-received fly ash and 1500℃ for the beneficiated fly ash. A higher sintering temperature and a shorter holding time are profitable to sintering mullite. The orthogonal test confirmed that the dominant factor affecting mullite synthesis is sintering temperature, and that the most profitable matching conditions are 200 MPa-1500℃-3 h for the as-received fly ash and 200 MPa-1500 ℃-4 h for the beneficiated fly ash.展开更多
Previous studies of coal sequence stratigraphy have concentrated on coals associated with paralic depositional systems.Little attention has been paid to their counterparts in non-marine intra-mountain coal basins.The ...Previous studies of coal sequence stratigraphy have concentrated on coals associated with paralic depositional systems.Little attention has been paid to their counterparts in non-marine intra-mountain coal basins.The northern Qaidam Basin of northwestern China has been extensively developed with abundant oil and gas as well as coal resources in its Jurassic non-marine successions.展开更多
Mineralogy and geochemistry of the four main workable coal seams(No.6,No.7,No.8,and No.11)of Late Permian age from the Songzao Coalfield,Chongqing,Southwest China,were examined using in-ductively coupled plasma-mass s...Mineralogy and geochemistry of the four main workable coal seams(No.6,No.7,No.8,and No.11)of Late Permian age from the Songzao Coalfield,Chongqing,Southwest China,were examined using in-ductively coupled plasma-mass spectrometry(ICP-MS),X-ray fluorescence spectrometry(XRF),cold-vapor absorption spectrometry(CV-AAS),ion-selective electrode(ISE),scanning electron mi-croscopy equipped with an energy-dispersive X-ray spectrometer(SEM-EDX),and X-ray diffraction analysis(XRD).The results showed that the main workable No.8 Coal that accounts for about 60%of the total coal reserves in the Songzao Coalfield was not enriched in hazardous trace elements.The No.11 Coal has high concentrations of alkaline elements,Be(9.14μg/g),Sc(12.9μg/g),Ti(9508μg/g),Mn(397μg/g),Co(23.7μg/g),Cu(108μg/g),Zn(123μg/g),Ga(32μg/g),Zr(1304μg/g),Nb(169μg/g),Hf(32.7μg/g),Ta(11.4μg/g),W(24.8μg/g),Hg(0.28μg/g),Pb(28.1μg/g),Th(24.1μg/g),and rare earth elements(509.62μg/g).The concentration of Nb and Ta in the No.11 Coal is higher than the industrial grade,and their potential utilization should be further studied.Besides pyrite,quartz,calcite,and clay minerals,trace minerals including chalcopyrite,marcasite,siderite,albite,mixed-layer clay minerals of illite and smectite,monazite,apatite,anatase,chlorite,and gypsum were found in the No.11 Coal.It should be noted that alabandite of hydrothermal origin and anatase occurring as cement were identi-fied in coal.In addition,the clayey microbands derived from alkaline volcanic ashes were identified in the coal.The dominant compositions of these clayey microbands were mixed-layer clay minerals of illite and smectite,which were interlayered with organic bands.The modes of occurrence of alkaline volcanic ash bands indicate that the volcanic activities were characterized by the multiple eruptions,short time interval and small scale for each eruption during peat accumulation.The alkaline volcanic ashes were the dominant factors for the enrichment of alkaline elements,Nb,Ta,Zr,Hf,and rare earth elements,and the sulfide minerals are the main carriers of Ga,Cu,and Hg in the No.11 Coal.展开更多
Background: Moxibustion is a traditional Chinese medicine(TCM) therapy in which mugwort(Artemisia vulgaris) floss is burned to warm and stimulate acupoints. The modality has been used traditionally for thousands of ye...Background: Moxibustion is a traditional Chinese medicine(TCM) therapy in which mugwort(Artemisia vulgaris) floss is burned to warm and stimulate acupoints. The modality has been used traditionally for thousands of years. However, smoke-related safety issues have recently been of concern, and little is known about moxa smoke and air quality in the clinical moxibustion environment.Objective: To assess the air quality in a typical moxibustion treatment room using particulate matter(PM) concentration and DNA oxidative damage at PM10.Methods: The study was conducted in August and November to December, 2011, at a TCM clinic in Beijing, China, in a moxibustion treatment room. A moxa-free treatment room and the outdoor area adjacent to the clinic were used as controls. PM10 concentrations were monitored with a portable digital dust indicator. The oxidative capacity of whole and water-soluble fractions of PM10 were detected using plasmid DNA assay. The results were shown as TD40 values; that is, the amount of PM10 that causes plasmid DNA damage of 40%.Results: Average PM10 concentrations in the moxibustion room were 2.56 mg m^(-3) in summer and 2.78 mg m^(-3) in winter, much higher than at control sites. For whole and water-soluble fractional PM10, the average summer TD40 values collected in the moxibustion room were 791.67 μg ml^(-1) and 876.33 μg ml^(-1) respectively, and the winter values were 779.86 μg ml^(-1) and 879.57 μg ml^(-1). These results of winter samples were significantly higher(p < 0.001) than the corresponding results from control sites. However, there was no statistical difference(p = 0.06)between the TD40 values of both the whole and water-soluble fractional PM10 from the moxibustion treatment room, while differences were significant in the general treatment room(p = 0.025) and at the outdoor site(P < 0.001).Conclusion: Our study shows that moxa smoke increases PM10 concentration. However, the oxidative capacity of PM10 in the moxibustion room was much lower than that at control sites with the same particulate burden, and the bioactivity at that site was mainly from the watersoluble fraction, another difference from the controls. This unexpected bioactivity is assumed to relate to the low toxicity of moxa smoke or to its proven antioxidant activity. Overall, further research is needed.展开更多
Due to the complexity of geological background and the adverseness of natural geographical environment in the Qinghai-Tibet Plateau,it is very difficult to carry out petroleum geological study in this region.The Qingh...Due to the complexity of geological background and the adverseness of natural geographical environment in the Qinghai-Tibet Plateau,it is very difficult to carry out petroleum geological study in this region.The Qinghai-Tibet Plateau is the only blank space of petroleum exploration on a large scale.The authors carried out the surface geochemical exploration of oil and gas in the Gangbatong-Ya'anxiang and Dongqiao-Nam Co of the Qinghai-Tibet region.Based on the data of actual detection and experiments in the studied area,the characteristics of concentration and profile distribution of the main geochemical exploration indicators(total adsorbed hydrocarbon,altered carbonate,thermal released mercury,etc.)were discussed.The origin of hydrocarbon was also discussed.Moreover,the oil and gas potential of different sections in the Qiangtang Basin and the Biru Basin were evaluated,which could provide references for the exploration and prediction of oil and gas in this region.The concentrations of total adsorbed hydrocarbons in the Ya'anxiang of Suoxian County-Zadong of Baqing County and the Jiecha-Dangxiong of Anduo County in the Qinghai-Tibet region are high,averaging 312.64μL·kg-1 and 164.36μL·kg-1.Their altered carbonate concentrations are relatively low,averaging 0.11%and 0.56%.Their concentrations of thermal released mercury are relatively high,averaging 13.09×10-9 and 1.94×10-9.Geochemical exploration results in fact reflect hydrocarbon information in the underground,which are mainly petroleum associated gas and over-matured cracking gas.The Jiecha-Charenluma and the Xiamaya'ertong-Suoba sections in the Qiangtang Basin are the most favorable ones for oil and gas and the Ekou-Zadong section is relatively favorable one,while the Nam Co and the Zigetangcuo-Dongqiao sections in the Biru Basin are the favorable ones for oil and gas,and the Jiang Co-Nading Co and the Ya'anxiang-Ya'ertong sections are relatively favorable ones.展开更多
Mineralogy and geochemistry of No.6 Coal from the Heidaigou Mine of the Jungar Coalfield of North China were studied using instrumental neu- tron activation analysis,inductively coupled-plasma mass spectroscopy,X-ray ...Mineralogy and geochemistry of No.6 Coal from the Heidaigou Mine of the Jungar Coalfield of North China were studied using instrumental neu- tron activation analysis,inductively coupled-plasma mass spectroscopy,X-ray fluorescence spectrometry,and scanning electron microscope equipped with an energy-dispersive X-ray spectrometer. The results show that gallium concentration is as high as 44.8 μg·g?1 in the whole coal-channel sample,and varies from 30.1 μg·g?1 to 76.0 μg·g?1 (mean 51.9 μg·g?1) in the main minable benches of No.6 Coal. Such high concentration of Ga in the coal is far higher than the industrial grade (30 μg·g?1). The thickness of the main minable benches accounts for 81.9% of the whole coal bed. The laboratory high-temperature ashes (550℃) of the main minable coal benches also contain a high concentration of Ga,varying from 62.2 μg·g?1 to 178 μg·g?1,with an average of 89.2 μg·g?1. The boehmite significantly enriched in No.6 Coal is the main carrier of the high Ga in the coal. Average concentration of Ga in boehmite is 0.09%. The av- erage content of boehmite is 6.1% in the whole coal and 7.5% in the main minable benches. Boehmite is derived from the bauxite in the weathered crust of the underlying Benxi Formation in the north of the basin during the peat accumulation. The colloidal idrargillite had been shortly transported from the weathered crust to the peat mire,and owing to the compaction of the overlying strata during the peat accumulation and early diagenesis,the idrargillite colloid had begun to be dehydrated,leading to boehmite formation. A pre- liminary estimation showed that the ensured and prospected reserves of Ga in No.6 Coal are up to 6.3 ×104t and 8.57×105t,indicating a superlarge galliumore deposit. The particular paleogeography of the Jungar Coalfield and the peculiar carrier of Ga in coal suggest that this Ga ore deposit is unique in the world. Rare earth elements are also enriched in coal and laboratory ashes. The weighted average concentra- tion of the total rare earth elements is 255 μg·g?1 and 830.36 μg·g?1 in the main minable benches and their laboratory ashes,respectively. Because Al is the main composition of boehmite,aluminum and rare earth elements in No.6 Coal are also the available and valuable resources.展开更多
The No. 6 Coal-bed from the Heidaigou Mine, Jungar Coalfield, Inner Mongolia is a super-large Ga deposit. The dominant carrier of Ga is boehmite in coal. The study of coal facies may provide genetic enrichment informa...The No. 6 Coal-bed from the Heidaigou Mine, Jungar Coalfield, Inner Mongolia is a super-large Ga deposit. The dominant carrier of Ga is boehmite in coal. The study of coal facies may provide genetic enrichment information of Ga and its carrier (boehmite) in the Ga deposit. On the basis of study on coal petrology and mineralogy, it was found that the No. 6 Coal-bed from the Heidaigou Mine of Jungar was enriched in inertinites and the microlitho-types were dominated by clarodurite. The maceral morphological features and association indicate that the coal-bed was formed in a dry sedimentary environment or in a periodic dry sedimentary environment caused by the alternating variations of groundwater level. The optimum conditions for the enrichment of Ga and its particular carrier (boehmite) were dominated by four transitional conditions: (1) the upper delta plain which was the transitional zone between alluvial and lower delta plains, (2) the transitional zone between the dry and wet forest swamps, being slightly apt to the dry one, (3) the transitional tree density between the thick and loose ones, and (4) the low moor that was the transitional zone between two high moors during peat accumulation.展开更多
Asian dust storm (ADS) samples were collected on March 20,2002 in Beijing,China. High-resolution field emission scanning electron microscopy with energy dispersive X-ray detector (FESEM-EDX) and X-ray diffraction (XRD...Asian dust storm (ADS) samples were collected on March 20,2002 in Beijing,China. High-resolution field emission scanning electron microscopy with energy dispersive X-ray detector (FESEM-EDX) and X-ray diffraction (XRD) were used to study the morphology,chemical compositions,number-size dis-tributions and mineralogical compositions of ADS particles. The mineral particles were major compo-nents in the ADS samples,accounting for 94% by number. The XRD analysis indicated that the dust particles were dominated by clay (40.3%),and quartz (19.5%),followed by plagioclase (8.4%),calcite (7.5%),K-feldspar (1.5%),hematite (0.9%),pyrite (0.9%),hornblende (0.4%) and gypsum (0.3%),with a certain amount of noncrystalline materials (20.3%). Clay minerals were mainly illite/smectite mixed lay-ers (78%),followed by illite (9%),kaolinite (6%),and chlorite (7%). In addition to these main minerals,FESEM-EDX also detected some trace minerals,such as dolomite,pyrite,thenardite,as well as heavy minerals represented by rutile,ilmenite and apatite. The mineralogical compositions of the 2002-03-20 Asian dust storm and the Saharan dust plumes were similar but the clay mineralogy showed a great distinction,with the illite/smectite mixed layers being common in the Asian dust storm but illite being common in the Saharan dust plumes.展开更多
文摘The concentration, distribution, and occurrence of rare earth elements (REEs) in coals as well as stone coalsin different geological periods from Chongqing were studied. The results show that the REE content in coals fromChongqing is much higher than that of the ordinary Chinese coals, the Late Paleozoic coals from North China, UScoals, and the world coals. Although the concentration of light rare earth elements (LREE) is higher than that of heavyrare earth elements (HREE), the ratio of LREE to HREE is as low as 5.11. The REE content decreases with thecoal-formation periods from old to new. The REE content in the Sinian stone coal is the highest, but it is the lowest inEarly Jurassic coals. The similar REE contents in bituminous coals and anthracite show that the metamorphism has alittle influence on REE content in coal. In addition, silicate association dominates the occurrence mode of REEs incoals from Chongqing.
文摘A severe Asian Dust Storm(ADS)event occurred on April 16-17th,2006 in northem China.Mineral components of dust samples were analyzed using X-ray diffraction(XRD).The result indicates that dust particles were dominated by quartz(37.4%)and clay(32.9%),followed by plagioclase(13.7%),with small amounts of calcite,K-feldspar,dolomite,homblende,and gypsum(all【10%).
文摘This paper analyses the sequence stratigraphy and palaeogeography of the Early and early Middle Jurassic coal measures in the Turpan-Hami Basin,northwestern China.The controls of the palaeogeography and sequence stratigraphy on the coal accumulation in this basin have been discussed.The results show that the coal measures were formed in a fluvial-delta-lacustrine sedimentary system,and a total of 4 third-order sequences were developed.
文摘The northern type Longtan Formation of the Late Permian in central Hunan is dominated by an assemblage of greyish black mudstone,siltstone,sandy mudstone,fine sandstone and coals,and contains a variety of sedimentary structures such as thin sandstone-mudstone interbedded bedding,flaser beddings,lenticular beddings.
文摘The Qinshui Basin in southeastern Shanxi Province is an important base for coalbed methane exploration and production in China.The methane reservoirs in this area are the Carboniferous and Permian coals and their thickness are strongly controlled by the depositional environments and the sequence stratigraphic framework.This paper analyzes the high-resolution sequence stratigraphy of the Permo-Carbo-niferous Taiyuan and Shanxi Formations.
基金This work was financed by the National Natural Science Foundation of China （Grant No. 40672103 , 40575065） the Program for New Century Excellent Talents in University of the Chinese Ministry of Education. The authors sincerely thank Professor Li Kaiqi for his constructive suggestions and useful discussions.
文摘In this paper, an experimental study was conducted in order to test the feasibility of sintering mullite directly from the high-alumina fly ash, without adding any extra material. The results show that the mullite contents in most sintered samples are over 70%. The samples sintered from the beneficiated fly ash have a higher content of mullite than those from the as-received fly ash under the same synthetic conditions. To obtain an equal amount of mullite, a higher sintering temperature is needed for the beneficiated fly ash than for the as-received fly ash. Considering the physical properties of sintered mullite, the favorable sintering temperature is 1400℃ for the as-received fly ash and 1500℃ for the beneficiated fly ash. A higher sintering temperature and a shorter holding time are profitable to sintering mullite. The orthogonal test confirmed that the dominant factor affecting mullite synthesis is sintering temperature, and that the most profitable matching conditions are 200 MPa-1500℃-3 h for the as-received fly ash and 200 MPa-1500 ℃-4 h for the beneficiated fly ash.
文摘Previous studies of coal sequence stratigraphy have concentrated on coals associated with paralic depositional systems.Little attention has been paid to their counterparts in non-marine intra-mountain coal basins.The northern Qaidam Basin of northwestern China has been extensively developed with abundant oil and gas as well as coal resources in its Jurassic non-marine successions.
基金Supported by the National Key Basic Research and Development Program(Grant No.2006CB202201)the National Natural Science Foundation of China(Grant No.40472083)the Foundation for the Author of National Excellent Doctoral Dissertation of China(Grant No.200448)
文摘Mineralogy and geochemistry of the four main workable coal seams(No.6,No.7,No.8,and No.11)of Late Permian age from the Songzao Coalfield,Chongqing,Southwest China,were examined using in-ductively coupled plasma-mass spectrometry(ICP-MS),X-ray fluorescence spectrometry(XRF),cold-vapor absorption spectrometry(CV-AAS),ion-selective electrode(ISE),scanning electron mi-croscopy equipped with an energy-dispersive X-ray spectrometer(SEM-EDX),and X-ray diffraction analysis(XRD).The results showed that the main workable No.8 Coal that accounts for about 60%of the total coal reserves in the Songzao Coalfield was not enriched in hazardous trace elements.The No.11 Coal has high concentrations of alkaline elements,Be(9.14μg/g),Sc(12.9μg/g),Ti(9508μg/g),Mn(397μg/g),Co(23.7μg/g),Cu(108μg/g),Zn(123μg/g),Ga(32μg/g),Zr(1304μg/g),Nb(169μg/g),Hf(32.7μg/g),Ta(11.4μg/g),W(24.8μg/g),Hg(0.28μg/g),Pb(28.1μg/g),Th(24.1μg/g),and rare earth elements(509.62μg/g).The concentration of Nb and Ta in the No.11 Coal is higher than the industrial grade,and their potential utilization should be further studied.Besides pyrite,quartz,calcite,and clay minerals,trace minerals including chalcopyrite,marcasite,siderite,albite,mixed-layer clay minerals of illite and smectite,monazite,apatite,anatase,chlorite,and gypsum were found in the No.11 Coal.It should be noted that alabandite of hydrothermal origin and anatase occurring as cement were identi-fied in coal.In addition,the clayey microbands derived from alkaline volcanic ashes were identified in the coal.The dominant compositions of these clayey microbands were mixed-layer clay minerals of illite and smectite,which were interlayered with organic bands.The modes of occurrence of alkaline volcanic ash bands indicate that the volcanic activities were characterized by the multiple eruptions,short time interval and small scale for each eruption during peat accumulation.The alkaline volcanic ashes were the dominant factors for the enrichment of alkaline elements,Nb,Ta,Zr,Hf,and rare earth elements,and the sulfide minerals are the main carriers of Ga,Cu,and Hg in the No.11 Coal.
基金supported by the National Basic Research Program of China(973 Program NO.2009CB522906)National Natural Science Foundation of China(NO.81072862)
文摘Background: Moxibustion is a traditional Chinese medicine(TCM) therapy in which mugwort(Artemisia vulgaris) floss is burned to warm and stimulate acupoints. The modality has been used traditionally for thousands of years. However, smoke-related safety issues have recently been of concern, and little is known about moxa smoke and air quality in the clinical moxibustion environment.Objective: To assess the air quality in a typical moxibustion treatment room using particulate matter(PM) concentration and DNA oxidative damage at PM10.Methods: The study was conducted in August and November to December, 2011, at a TCM clinic in Beijing, China, in a moxibustion treatment room. A moxa-free treatment room and the outdoor area adjacent to the clinic were used as controls. PM10 concentrations were monitored with a portable digital dust indicator. The oxidative capacity of whole and water-soluble fractions of PM10 were detected using plasmid DNA assay. The results were shown as TD40 values; that is, the amount of PM10 that causes plasmid DNA damage of 40%.Results: Average PM10 concentrations in the moxibustion room were 2.56 mg m^(-3) in summer and 2.78 mg m^(-3) in winter, much higher than at control sites. For whole and water-soluble fractional PM10, the average summer TD40 values collected in the moxibustion room were 791.67 μg ml^(-1) and 876.33 μg ml^(-1) respectively, and the winter values were 779.86 μg ml^(-1) and 879.57 μg ml^(-1). These results of winter samples were significantly higher(p < 0.001) than the corresponding results from control sites. However, there was no statistical difference(p = 0.06)between the TD40 values of both the whole and water-soluble fractional PM10 from the moxibustion treatment room, while differences were significant in the general treatment room(p = 0.025) and at the outdoor site(P < 0.001).Conclusion: Our study shows that moxa smoke increases PM10 concentration. However, the oxidative capacity of PM10 in the moxibustion room was much lower than that at control sites with the same particulate burden, and the bioactivity at that site was mainly from the watersoluble fraction, another difference from the controls. This unexpected bioactivity is assumed to relate to the low toxicity of moxa smoke or to its proven antioxidant activity. Overall, further research is needed.
基金Supported by New-century Excellent Talent Program of Ministry of Education of China(Grant No.NCET-06-0204)National Natural Science Foundation of China(Grant No.40572085)"the 9th Five-Year Plan"of Scientific and Technological Program of CNPC(Grant No.BR95YZ2-02)
文摘Due to the complexity of geological background and the adverseness of natural geographical environment in the Qinghai-Tibet Plateau,it is very difficult to carry out petroleum geological study in this region.The Qinghai-Tibet Plateau is the only blank space of petroleum exploration on a large scale.The authors carried out the surface geochemical exploration of oil and gas in the Gangbatong-Ya'anxiang and Dongqiao-Nam Co of the Qinghai-Tibet region.Based on the data of actual detection and experiments in the studied area,the characteristics of concentration and profile distribution of the main geochemical exploration indicators(total adsorbed hydrocarbon,altered carbonate,thermal released mercury,etc.)were discussed.The origin of hydrocarbon was also discussed.Moreover,the oil and gas potential of different sections in the Qiangtang Basin and the Biru Basin were evaluated,which could provide references for the exploration and prediction of oil and gas in this region.The concentrations of total adsorbed hydrocarbons in the Ya'anxiang of Suoxian County-Zadong of Baqing County and the Jiecha-Dangxiong of Anduo County in the Qinghai-Tibet region are high,averaging 312.64μL·kg-1 and 164.36μL·kg-1.Their altered carbonate concentrations are relatively low,averaging 0.11%and 0.56%.Their concentrations of thermal released mercury are relatively high,averaging 13.09×10-9 and 1.94×10-9.Geochemical exploration results in fact reflect hydrocarbon information in the underground,which are mainly petroleum associated gas and over-matured cracking gas.The Jiecha-Charenluma and the Xiamaya'ertong-Suoba sections in the Qiangtang Basin are the most favorable ones for oil and gas and the Ekou-Zadong section is relatively favorable one,while the Nam Co and the Zigetangcuo-Dongqiao sections in the Biru Basin are the favorable ones for oil and gas,and the Jiang Co-Nading Co and the Ya'anxiang-Ya'ertong sections are relatively favorable ones.
基金the National Natural Science Foundation of China （Grant No. 40472083）the Key Science and Technology Project of Ministry of Education of China （Grant No. 105020） the Foundation of National Excellent Doctoral Dissertation of China （Grant No. 200448）.
文摘Mineralogy and geochemistry of No.6 Coal from the Heidaigou Mine of the Jungar Coalfield of North China were studied using instrumental neu- tron activation analysis,inductively coupled-plasma mass spectroscopy,X-ray fluorescence spectrometry,and scanning electron microscope equipped with an energy-dispersive X-ray spectrometer. The results show that gallium concentration is as high as 44.8 μg·g?1 in the whole coal-channel sample,and varies from 30.1 μg·g?1 to 76.0 μg·g?1 (mean 51.9 μg·g?1) in the main minable benches of No.6 Coal. Such high concentration of Ga in the coal is far higher than the industrial grade (30 μg·g?1). The thickness of the main minable benches accounts for 81.9% of the whole coal bed. The laboratory high-temperature ashes (550℃) of the main minable coal benches also contain a high concentration of Ga,varying from 62.2 μg·g?1 to 178 μg·g?1,with an average of 89.2 μg·g?1. The boehmite significantly enriched in No.6 Coal is the main carrier of the high Ga in the coal. Average concentration of Ga in boehmite is 0.09%. The av- erage content of boehmite is 6.1% in the whole coal and 7.5% in the main minable benches. Boehmite is derived from the bauxite in the weathered crust of the underlying Benxi Formation in the north of the basin during the peat accumulation. The colloidal idrargillite had been shortly transported from the weathered crust to the peat mire,and owing to the compaction of the overlying strata during the peat accumulation and early diagenesis,the idrargillite colloid had begun to be dehydrated,leading to boehmite formation. A pre- liminary estimation showed that the ensured and prospected reserves of Ga in No.6 Coal are up to 6.3 ×104t and 8.57×105t,indicating a superlarge galliumore deposit. The particular paleogeography of the Jungar Coalfield and the peculiar carrier of Ga in coal suggest that this Ga ore deposit is unique in the world. Rare earth elements are also enriched in coal and laboratory ashes. The weighted average concentra- tion of the total rare earth elements is 255 μg·g?1 and 830.36 μg·g?1 in the main minable benches and their laboratory ashes,respectively. Because Al is the main composition of boehmite,aluminum and rare earth elements in No.6 Coal are also the available and valuable resources.
基金Supported by the National Basic Research Program of China (Grant Nos. 2003CB214607 and 2006CB202201) and the National Natural Science Foundation of China (Grant Nos. 40472083 and 40672102)
文摘The No. 6 Coal-bed from the Heidaigou Mine, Jungar Coalfield, Inner Mongolia is a super-large Ga deposit. The dominant carrier of Ga is boehmite in coal. The study of coal facies may provide genetic enrichment information of Ga and its carrier (boehmite) in the Ga deposit. On the basis of study on coal petrology and mineralogy, it was found that the No. 6 Coal-bed from the Heidaigou Mine of Jungar was enriched in inertinites and the microlitho-types were dominated by clarodurite. The maceral morphological features and association indicate that the coal-bed was formed in a dry sedimentary environment or in a periodic dry sedimentary environment caused by the alternating variations of groundwater level. The optimum conditions for the enrichment of Ga and its particular carrier (boehmite) were dominated by four transitional conditions: (1) the upper delta plain which was the transitional zone between alluvial and lower delta plains, (2) the transitional zone between the dry and wet forest swamps, being slightly apt to the dry one, (3) the transitional tree density between the thick and loose ones, and (4) the low moor that was the transitional zone between two high moors during peat accumulation.
基金the National Basic Research Program of China (Grant No. 2006CB403701)the National Natural Science Foundation of China (Grant Nos. 40275040 and 40575065)the Program for New Century Excellent Talents in University of the Ministry of Education of China
文摘Asian dust storm (ADS) samples were collected on March 20,2002 in Beijing,China. High-resolution field emission scanning electron microscopy with energy dispersive X-ray detector (FESEM-EDX) and X-ray diffraction (XRD) were used to study the morphology,chemical compositions,number-size dis-tributions and mineralogical compositions of ADS particles. The mineral particles were major compo-nents in the ADS samples,accounting for 94% by number. The XRD analysis indicated that the dust particles were dominated by clay (40.3%),and quartz (19.5%),followed by plagioclase (8.4%),calcite (7.5%),K-feldspar (1.5%),hematite (0.9%),pyrite (0.9%),hornblende (0.4%) and gypsum (0.3%),with a certain amount of noncrystalline materials (20.3%). Clay minerals were mainly illite/smectite mixed lay-ers (78%),followed by illite (9%),kaolinite (6%),and chlorite (7%). In addition to these main minerals,FESEM-EDX also detected some trace minerals,such as dolomite,pyrite,thenardite,as well as heavy minerals represented by rutile,ilmenite and apatite. The mineralogical compositions of the 2002-03-20 Asian dust storm and the Saharan dust plumes were similar but the clay mineralogy showed a great distinction,with the illite/smectite mixed layers being common in the Asian dust storm but illite being common in the Saharan dust plumes.
