At 23:59 on December 18, 2023, a strong earthquake (M 6.2) struck Jishishan County in Gansu province, China, which is situated in the transition zone between Qinghai-Xizang Plateau and the Loess Plateau.The focal dept...At 23:59 on December 18, 2023, a strong earthquake (M 6.2) struck Jishishan County in Gansu province, China, which is situated in the transition zone between Qinghai-Xizang Plateau and the Loess Plateau.The focal depth is 10 km, and the epicenter (35.70°N and 102.79°E) is about 100 km southwest away from Lanzhou, the capital city of Gansu province. As of December 31, 2023, the earthquake has caused 151 people dead and 979 people wounded in Gansu and Qinghai.展开更多
Clarifying the impact of livelihood interventions on the livelihood resilience of farmers in undeveloped mountain areas can not only optimize interventions,but also provide experiential support for global poverty alle...Clarifying the impact of livelihood interventions on the livelihood resilience of farmers in undeveloped mountain areas can not only optimize interventions,but also provide experiential support for global poverty alleviation.To analyze the impact of multiple livelihood interventions on livelihood resilience,we constructed an analytical framework and analyzed the enjoyment of livelihood interventions and the heterogeneity of livelihood resilience among out-of-poverty farmers in the Longnan mountain areas,China.Then,we studied the impact of intervention intensity on livelihood resilience through the multiple linear regression model.The results revealed that:1)the livelihood interventions enjoyed by out-of-poverty farmer in mountain areas were multiple.The proportion of farmers enjoyed diversified livelihood interventions was in descending order of high mountain areas,semi-mountain area and Chuanba valley areas.2)The overall livelihood resilience of farmers in Longnan mountain areas was generally low,with an average of 0.299.There were significant differences in the livelihood resilience of farmers across different geographic areas in the study area and types of interventions.3)The effects of industry interventions,employment interventions and education interventions were significant.The endogenous power of farmers not only had a significant positive effect on livelihood resilience,but also positively moderated the impact of the intensity of interventions on livelihood resilience.In addition,the household dependency ratio and the average altitude of the village area had a significant negative impact on their livelihood resilience.展开更多
As a region inhabited by large populations of ethnic minority groups, Gansu province boasts rich ethnic cultural resources which reflect traditional culture and intangible cultural heritage that had taken shape thousa...As a region inhabited by large populations of ethnic minority groups, Gansu province boasts rich ethnic cultural resources which reflect traditional culture and intangible cultural heritage that had taken shape thousands of years ago. Among these are various ethnic folk chess games. They are time-honored with many types such as the “Fang” chess of the Hui ethnic group, the “Jiu” chess of the Tibetans, the “King and Ministers” chess, the Mongolian chess, the Mongolian military chess, etc. These games embody distinctive ethnic and regional characteristics, as well as the cultural elements of a particular ethnic minority group. It is of great significance, therefore, to study the ethnic chess by collecting, documenting and comparing different types of related chess. The paper explores ways to standardize, protect and promote them scientifically in joint efforts, and draws a conclusion that examining their significance in the present era and the ethnic characteristics is the key to understanding the profound culture behind the chess.展开更多
From August 17 to 23,2023,the Yellow River Tourism Overseas Promotion Season 2023 launched the"Gansu Overseas Promotion Week"to present the Gansu Cultural Tourism Promotional Video,Gansu Intangible Cultural ...From August 17 to 23,2023,the Yellow River Tourism Overseas Promotion Season 2023 launched the"Gansu Overseas Promotion Week"to present the Gansu Cultural Tourism Promotional Video,Gansu Intangible Cultural Heritage Short Video and the"Symphony Silk Road and Satisfactory Gansu"-Gansu in Chinese Folk Music series of short videos to the global public.展开更多
As a basic natural resource and strategic economic resource,the development and utilization of water resources is an important issue related to the national economy and people's livelihood.How to scientifically ev...As a basic natural resource and strategic economic resource,the development and utilization of water resources is an important issue related to the national economy and people's livelihood.How to scientifically evaluate the water resources carrying capacity is the premise to improve the regional water resources carrying capacity and ensure the regional water security.The Gansu section of the Yellow River basin is an important water conservation and recharge area.Whether the water resources in this area can ensure the normal operation of the ecosystem and whether it can carry the sustainable development of social economy is the key to realize the high-quality development of the Yellow River basin.In this study,from the three dimensions of water consumption per capita,water consumption of 10000 yuan GDP and ecological water use rate,by constructing the evaluation index system and index grading standard of water resources carrying capacity,the fuzzy comprehensive evaluation model was used to evaluate the water resources carrying capacity of Gansu section of the Yellow River Basin,in order to provide theoretical decision-making basis for the comprehensive development,utilization and planning management of water resources in Gansu section of the Yellow River basin and even the whole basin,and help the high-quality development of the Yellow River basin.展开更多
To implement the CPC CentralCommittee’s strategy of slanting theeconomic construction to the Midand West of China and to further promote thedevelopment and cooperation of economyand trade between the East and West, t...To implement the CPC CentralCommittee’s strategy of slanting theeconomic construction to the Midand West of China and to further promote thedevelopment and cooperation of economyand trade between the East and West, theEast-West Business and Trade Talks wereheld by the China Council for the Promotionof International Trade (CCPIT). At theconference, Mr. Cui Zhenghua, vice governorof Gansu Province and concurrently chairmanof the Gansu Subcouncil of the CCPIT,delivered a speech on the economiccooperation and development between theEast and West of China.展开更多
Xifeng (西峰) oilfield was recently found in the southwest of the Ordos basin. The oil source rocks are the Chang 7 Section of Yanchang (延长) Formation. In order to study the paleoclimate that controlled the form...Xifeng (西峰) oilfield was recently found in the southwest of the Ordos basin. The oil source rocks are the Chang 7 Section of Yanchang (延长) Formation. In order to study the paleoclimate that controlled the formation of source rocks, a systemically palynological research on related beds in Yanchang Formation has been carried out. The core samples were analyzed with classical palynological techniques and the organic-walled sporomorphs from these samples were observed, identified and photographed under a light microscopy and a fluorescence microscopy. Abundant sporopollen were found in drilling cores from Chang 8 and Chang 7 sections, and two assemblages were distinguished: the Aratisporites-Punctatisporites assemblage and the Asseretospora-Walchiites assemblage. Their characteristics are similar to those of the assemblage of Tongchuan (铜川 ) Formation and the assemblage of Yanchang Formation in southeast Ordos basin, respectively. Their geological times are Ladinian of late Middle Triassic and Carnian of early Late Triassic, respectively. The correlation of palynoflora with their parent plants suggests the paleoclimate of eastern Gansu (甘肃) Province in the Middle and Late Triassic was warm and rainy with prosperous vegetation. The palynoflora indicated the area was in a temperate to subtropical zone then. Both the ecological types and differentiation degree curves of sporopollen indicated the period during Chang 8 and Chang 7 sections was warm and wet, and the phase accorded with large-scale lake transgression in Chang 8 Section and the largest lake area in Chang 7 Section. North China in Middle and Late Triassic was located in a warm and rainy, temperate and subtropi- cal zone. The palynofloras in Chang 8 and Chang 7 sections have the characteristics of North China flora, however they also indicate wetter and warmer climate due to their proximity to the large lakes. The period of Chang 8 to Chang 7 sections is the climax of the expansion of the lake, and the bloom of fresh algae during the period, which helped form the high-quality source rocks in Chang 7 Section.展开更多
The ductile shear zone-type gold deposit is a kind that both the ore-forming mechanism and ore-controlling factors are closely related to the ductile shear zone and its evolution. Ductile shear zone develops in Beisha...The ductile shear zone-type gold deposit is a kind that both the ore-forming mechanism and ore-controlling factors are closely related to the ductile shear zone and its evolution. Ductile shear zone develops in Beishan area, Gansu of Northwest China, and develops especially well in the south belt. The controls of the ductile shear zone on gold deposits are as follows. (1) The regional distribution of gold deposits (and gold spots) is controlled by the ductile shear zone. (2) The ductile-brittle shear zone is formed in the evolution process of ductile shear zone and both are only ore-bearing structures and control the shape, attitude, scale, and distribution of mineralization zones and ore-bodies. (3) Compresso-shear ductile deformation results in that the main kind of gold mineralization is altered mylonite type and the main alteralization is metasomatic. (4) Ore-bearing fracture systems are mainly P-type ones, some D-type and R-type ones, but only individual R'-type and T-type ones. (5) Dynamic differen- tiation and dynamic metamorphic hydrothermal solution resulting from ductile deformation is one of the sources of ore-forming fluid of gold mineralization, and this is identical with that ore-forming materials are mainly from metamorphic rocks, and ore-forming fluid is mainly composed of metamorphic water, and with the fluid inclusion and geo-chemical characteristics of the deposit. (6) There is a negative correlation between the gold abundance and susceptibility anlsotropy (P) of the altered mylonlte samples from the deposit, which shows that the gold mineralization is slightly later than the structural deformation. All above further expound the ore-forming model of the ductile shear zone type of gold deposits.展开更多
Warm and humid climate and gentle hilly topography have provided favourable conditions for the devel-opment of the weathering crust of the granite intrusions in the Longnan area, Jiangxi Province. REE is mostlyconcent...Warm and humid climate and gentle hilly topography have provided favourable conditions for the devel-opment of the weathering crust of the granite intrusions in the Longnan area, Jiangxi Province. REE is mostlyconcentrated in an adsorption state in clay in the wholly weathered zone. The rare-earth minerals enriched inthe parent rocks provided the source material for the REE enrichment. Exchangeable REE accounts for48-86%. Extraction experiments and stable isotopic study of clay minerals suggest that the downward infiltra-tion of meteoric water and increasing gradient of pH values have played an important role in the enrichment ofREE during the progressive weathering. Slight fractionation of individual REE can not change their distribu-tion patterns in the profiles. which are inherited from the parent rocks.展开更多
[Objective] The paper was to discuss why the top of tall barchan dunes and barchan chains widespread in single prevailing wind area had not been leveled by wind erosion. [Method] Based on the preliminary survey of dis...[Objective] The paper was to discuss why the top of tall barchan dunes and barchan chains widespread in single prevailing wind area had not been leveled by wind erosion. [Method] Based on the preliminary survey of distribution status,the morphological characteristics and environmental conditions of barchan dunes and barchan chains in Hexi desert area of Gansu were investigated in details. The significance of difference between samples and significance of correlation between indicators were examined via variance test. [Result] Barchan dunes and barchan chains in Hexi desert area of Gansu distributed at the leeward direction of desert fringe,generally in patch distribution. The distribution area was gravelly beach or cohesive gravel beach,with broader dune slack; winds in distribution area of barchan dunes and barchan chains blew obviously from one direction,while winds at other directions were light or occasionally strong but with low frequency;the barchan dune in the desert fringe of Hexi desert area of Gansu was relatively tall,while barchan chain was even more taller and larger. Coincidence or separation of the dune peak and the sand ridge might be related to distribution frequency of dominant prevailing wind or wind at opposite direction and the observation seasons.[Conclusion]Studying top stability of barchan dune has an important academic value in revealing blowing sand movement rule at desert fringe,invasion of sand flow,and expansion of desert.展开更多
The 2008 Wenchuan earthquake has a significant impact on the seismicity of nearby regions. The Longnan earthquake which occurred on September 12,2008 in Gansu Province was out of the aftershock zone. Reliable source p...The 2008 Wenchuan earthquake has a significant impact on the seismicity of nearby regions. The Longnan earthquake which occurred on September 12,2008 in Gansu Province was out of the aftershock zone. Reliable source parameters are essential for understanding the seismogenic process of this earthquake. Therefore,three approaches are adopted to study the source parameters of this event. The focal mechanism is obtained with the g CAP method that takes non-Double-Couple(non-DC)component into account. The two fault planes are NP1:150°/45°/81° and NP2:342°/45°/98°,while the non-DC component is about 53%. The focal depth is 1. 6 km,which indicates the Longnan earthquake is a shallow event. Furthermore,this result is also in good agreement with results obtained with two other approaches:amplitude spectra of Rayleigh wave and surface displacement from In SAR measurement. To analyze the cause of the event,coulomb failure stress change caused by the Wenchuan earthquake on the Longnan earthquake fault plane is calculated. The result shows that coulomb stress change is 30 k Pa around the Longnan earthquake hypocenter,which exceeds the typical triggering threshold of 10 k Pa. The research indicates that the Wenchuan earthquake probably promote the happening of the Longnan earthquake.展开更多
The firework algorithm(FWA) is a novel swarm intelligence-based method recently proposed for the optimization of multi-parameter, nonlinear functions. Numerical waveform inversion experiments using a synthetic model...The firework algorithm(FWA) is a novel swarm intelligence-based method recently proposed for the optimization of multi-parameter, nonlinear functions. Numerical waveform inversion experiments using a synthetic model show that the FWA performs well in both solution quality and efficiency. We apply the FWA in this study to crustal velocity structure inversion using regional seismic waveform data of central Gansu on the northeastern margin of the Qinghai-Tibet plateau. Seismograms recorded from the moment magnitude(MW) 5.4 Minxian earthquake enable obtaining an average crustal velocity model for this region. We initially carried out a series of FWA robustness tests in regional waveform inversion at the same earthquake and station positions across the study region,inverting two velocity structure models, with and without a low-velocity crustal layer; the accuracy of our average inversion results and their standard deviations reveal the advantages of the FWA for the inversion of regional seismic waveforms. We applied the FWA across our study area using three component waveform data recorded by nine broadband permanent seismic stations with epicentral distances ranging between 146 and 437 km. These inversion results show that the average thickness of the crust in this region is 46.75 km, while thicknesses of the sedimentary layer, and the upper, middle, and lower crust are 3.15,15.69, 13.08, and 14.83 km, respectively. Results also show that the P-wave velocities of these layers and the upper mantle are 4.47, 6.07, 6.12, 6.87, and 8.18 km/s,respectively.展开更多
Caligula Japonica has continuously broken out in large scale in Longnan City, Gansu Province of China, causing heavy economic losses. In order to ef- fectively control the insect and to increase the production benefit...Caligula Japonica has continuously broken out in large scale in Longnan City, Gansu Province of China, causing heavy economic losses. In order to ef- fectively control the insect and to increase the production benefit of walnut in Longnan, the authors have investigated and observed the morphological characters and living habits of C. Japonica. The major causes of continuous large-scale occurrence of C. Japonica in Longnan City are analyzed concretely, and the integrated con- trol measures are put forward from the aspects of silvicultural measures, physical control, chemical control and biological control.展开更多
Hyperspectral remote sensing is now a frontier of the remote sensing technology. Airborne hyperspectral remote sensing data have hundreds of narrow bands to obtain complete and continuous ground-object spectra. Theref...Hyperspectral remote sensing is now a frontier of the remote sensing technology. Airborne hyperspectral remote sensing data have hundreds of narrow bands to obtain complete and continuous ground-object spectra. Therefore, they can be effectively used to identify these grotmd objects which are difficult to discriminate by using wide-band data, and show much promise in geological survey. At the height of 1500 m, have 36 bands in visible to the CASI hyperspectral data near-infrared spectral range, with a spectral resolution of 19 nm and a space resolution of 0.9 m. The SASI data have 101 bands in the shortwave infrared spectral range, with a spectral resolution of 15 nm and a space resolution of 2.25 m. In 2010, China Geological Survey deployed an airborne CASI/SASI hyperspectral measurement project, and selected the Liuyuan and Fangshankou areas in the Beishan metallogenic belt of Gansu Province, and the Nachitai area of East Kunlun metallogenic belt in Qinghai Province to conduct geological survey. The work period of this project was three years.展开更多
Based on the observation data of temperature in Chengxian meteorological station( the climate representative station of Longnan City,Gansu Province) during 1961-2014,the annual,seasonal and monthly changes of temper...Based on the observation data of temperature in Chengxian meteorological station( the climate representative station of Longnan City,Gansu Province) during 1961-2014,the annual,seasonal and monthly changes of temperature were analyzed,and the abrupt changes in relevant variables were tested using the cumulative anomaly method. The results showed that annual average temperature in Chengxian County increased by 0. 138 ℃/10 a in the past 54 years. There was an obvious sudden change in annual average temperature around 1996. The annual average temperature showed a downward trend before 1996 and an upward trend after 1996. Average temperature in spring,summer,autumn and winter increased by 0. 113,0. 028,0. 157 and 0. 259 ℃/10 a respectively. The fluctuation of average temperature in spring and winter was the largest,followed by summer,while the fluctuation was the smallest in autumn. There were certain differences between various seasons in terms of the years with sudden changes in average temperature,which was not consistent with the years with the sudden changes in annual average temperature. The changing rate of monthly average temperature was the largest in February( up to 0. 412 ℃/10 a),followed by March,April and November,but it was the smallest in May( only 0. 005 ℃/10 a). The maximum of monthly average temperature appeared mostly in the 21 stcentury,while the minimum appeared in the 20 thcentury.展开更多
The Gansu Rare Earth Corporation(GREC)which has fixed assetsof about RMB 100 million yuan is the largest RE enterprise in Asia.GREC is affiliated to the China National Nonferrous Metals In-dustry Corporation and is lo...The Gansu Rare Earth Corporation(GREC)which has fixed assetsof about RMB 100 million yuan is the largest RE enterprise in Asia.GREC is affiliated to the China National Nonferrous Metals In-dustry Corporation and is located in Baiyin city, Gansu province, P.R.China, covering a area of 105 ha.GREC is a corporation integrating technology, industry and trade.GREC provides a complete RE production, a production covering frommining, ore-dressing to metallurgy. Besides the mining and ore-dres-sing plants jointly managed in Jiangxi, Sichuan and Fujian provinces,展开更多
Two Mesozoic intramontane basins are developed in the Dunhuang-Yumenguan-Jiuquan area of Gansu Province,China,i.e.,the Gongpoquan Basin(E97°30′-98°10′,N41°30′-41°45′)and the Yujingzi Basin(E...Two Mesozoic intramontane basins are developed in the Dunhuang-Yumenguan-Jiuquan area of Gansu Province,China,i.e.,the Gongpoquan Basin(E97°30′-98°10′,N41°30′-41°45′)and the Yujingzi Basin(E98°15′-99°00′,N40°15'-40°40')(Fig.1).A large number of dinosaurs and other fossils have been discovered in these two basins,which are called dinosaur'tribes'by paleontologists.展开更多
In the last few years, Gansu Province hasmade a great effort to perfect itsinfrastructure in terms of highways,airports, posts and telecommunications andrailways, aiming at increasing foreigninvestment in Gansu. The P...In the last few years, Gansu Province hasmade a great effort to perfect itsinfrastructure in terms of highways,airports, posts and telecommunications andrailways, aiming at increasing foreigninvestment in Gansu. The Preferential Methodsfor More Foreign Investment of GansuProvince, which were revised recently, isalso part of the effort. The Preferential Methods for MoreForeign Investment, issued by the GansuProvincial Government in 1992, have had展开更多
Gansu, situated at the juncture of theQingzang Plateau, Inner MongoliaPlateau and loess plateau, with aterritory of 454,000 square kilometres, isbounded by Inner Mongolia, Shaanxi, Ningxia,Xinjiang, Qinghai and Sichua...Gansu, situated at the juncture of theQingzang Plateau, Inner MongoliaPlateau and loess plateau, with aterritory of 454,000 square kilometres, isbounded by Inner Mongolia, Shaanxi, Ningxia,Xinjiang, Qinghai and Sichuan. It even sharesa short border with Mongolia. There are 41nationalities, about 24.3795 million people,inhabiting the five municipalities under thejurisdiction of Gansu. There are also sevenprefectures and two ethnic group展开更多
基金financially supported by the National Natural Science Foundation of China(Grant No.U1939209)the Natural Science Foundation of Gansu Province(Grant No.22JR11RA091).
文摘At 23:59 on December 18, 2023, a strong earthquake (M 6.2) struck Jishishan County in Gansu province, China, which is situated in the transition zone between Qinghai-Xizang Plateau and the Loess Plateau.The focal depth is 10 km, and the epicenter (35.70°N and 102.79°E) is about 100 km southwest away from Lanzhou, the capital city of Gansu province. As of December 31, 2023, the earthquake has caused 151 people dead and 979 people wounded in Gansu and Qinghai.
基金Under the auspices of National Natural Science Foundation of China(No.41971268)。
文摘Clarifying the impact of livelihood interventions on the livelihood resilience of farmers in undeveloped mountain areas can not only optimize interventions,but also provide experiential support for global poverty alleviation.To analyze the impact of multiple livelihood interventions on livelihood resilience,we constructed an analytical framework and analyzed the enjoyment of livelihood interventions and the heterogeneity of livelihood resilience among out-of-poverty farmers in the Longnan mountain areas,China.Then,we studied the impact of intervention intensity on livelihood resilience through the multiple linear regression model.The results revealed that:1)the livelihood interventions enjoyed by out-of-poverty farmer in mountain areas were multiple.The proportion of farmers enjoyed diversified livelihood interventions was in descending order of high mountain areas,semi-mountain area and Chuanba valley areas.2)The overall livelihood resilience of farmers in Longnan mountain areas was generally low,with an average of 0.299.There were significant differences in the livelihood resilience of farmers across different geographic areas in the study area and types of interventions.3)The effects of industry interventions,employment interventions and education interventions were significant.The endogenous power of farmers not only had a significant positive effect on livelihood resilience,but also positively moderated the impact of the intensity of interventions on livelihood resilience.In addition,the household dependency ratio and the average altitude of the village area had a significant negative impact on their livelihood resilience.
文摘As a region inhabited by large populations of ethnic minority groups, Gansu province boasts rich ethnic cultural resources which reflect traditional culture and intangible cultural heritage that had taken shape thousands of years ago. Among these are various ethnic folk chess games. They are time-honored with many types such as the “Fang” chess of the Hui ethnic group, the “Jiu” chess of the Tibetans, the “King and Ministers” chess, the Mongolian chess, the Mongolian military chess, etc. These games embody distinctive ethnic and regional characteristics, as well as the cultural elements of a particular ethnic minority group. It is of great significance, therefore, to study the ethnic chess by collecting, documenting and comparing different types of related chess. The paper explores ways to standardize, protect and promote them scientifically in joint efforts, and draws a conclusion that examining their significance in the present era and the ethnic characteristics is the key to understanding the profound culture behind the chess.
文摘From August 17 to 23,2023,the Yellow River Tourism Overseas Promotion Season 2023 launched the"Gansu Overseas Promotion Week"to present the Gansu Cultural Tourism Promotional Video,Gansu Intangible Cultural Heritage Short Video and the"Symphony Silk Road and Satisfactory Gansu"-Gansu in Chinese Folk Music series of short videos to the global public.
基金Supported by Gansu Province 2023 Education Science and Technology Innovation Project(2023B-431).
文摘As a basic natural resource and strategic economic resource,the development and utilization of water resources is an important issue related to the national economy and people's livelihood.How to scientifically evaluate the water resources carrying capacity is the premise to improve the regional water resources carrying capacity and ensure the regional water security.The Gansu section of the Yellow River basin is an important water conservation and recharge area.Whether the water resources in this area can ensure the normal operation of the ecosystem and whether it can carry the sustainable development of social economy is the key to realize the high-quality development of the Yellow River basin.In this study,from the three dimensions of water consumption per capita,water consumption of 10000 yuan GDP and ecological water use rate,by constructing the evaluation index system and index grading standard of water resources carrying capacity,the fuzzy comprehensive evaluation model was used to evaluate the water resources carrying capacity of Gansu section of the Yellow River Basin,in order to provide theoretical decision-making basis for the comprehensive development,utilization and planning management of water resources in Gansu section of the Yellow River basin and even the whole basin,and help the high-quality development of the Yellow River basin.
文摘To implement the CPC CentralCommittee’s strategy of slanting theeconomic construction to the Midand West of China and to further promote thedevelopment and cooperation of economyand trade between the East and West, theEast-West Business and Trade Talks wereheld by the China Council for the Promotionof International Trade (CCPIT). At theconference, Mr. Cui Zhenghua, vice governorof Gansu Province and concurrently chairmanof the Gansu Subcouncil of the CCPIT,delivered a speech on the economiccooperation and development between theEast and West of China.
基金This paper is financially supported by"Prominent Youngster in Western China" Science Foundation of Chinese Academy of Sciences ( No .CAS2002-404-01) and the Gansu Province Young and Middle Scientists Science Foundation .
文摘Xifeng (西峰) oilfield was recently found in the southwest of the Ordos basin. The oil source rocks are the Chang 7 Section of Yanchang (延长) Formation. In order to study the paleoclimate that controlled the formation of source rocks, a systemically palynological research on related beds in Yanchang Formation has been carried out. The core samples were analyzed with classical palynological techniques and the organic-walled sporomorphs from these samples were observed, identified and photographed under a light microscopy and a fluorescence microscopy. Abundant sporopollen were found in drilling cores from Chang 8 and Chang 7 sections, and two assemblages were distinguished: the Aratisporites-Punctatisporites assemblage and the Asseretospora-Walchiites assemblage. Their characteristics are similar to those of the assemblage of Tongchuan (铜川 ) Formation and the assemblage of Yanchang Formation in southeast Ordos basin, respectively. Their geological times are Ladinian of late Middle Triassic and Carnian of early Late Triassic, respectively. The correlation of palynoflora with their parent plants suggests the paleoclimate of eastern Gansu (甘肃) Province in the Middle and Late Triassic was warm and rainy with prosperous vegetation. The palynoflora indicated the area was in a temperate to subtropical zone then. Both the ecological types and differentiation degree curves of sporopollen indicated the period during Chang 8 and Chang 7 sections was warm and wet, and the phase accorded with large-scale lake transgression in Chang 8 Section and the largest lake area in Chang 7 Section. North China in Middle and Late Triassic was located in a warm and rainy, temperate and subtropi- cal zone. The palynofloras in Chang 8 and Chang 7 sections have the characteristics of North China flora, however they also indicate wetter and warmer climate due to their proximity to the large lakes. The period of Chang 8 to Chang 7 sections is the climax of the expansion of the lake, and the bloom of fresh algae during the period, which helped form the high-quality source rocks in Chang 7 Section.
基金This paper is supported by the National 305 Program (Nos. 2001BA609A-07-02, 2006BAB07B02-04)Research Foundation of former Ministry of Geology and Mineral Re-sources of China (No.96-21)
文摘The ductile shear zone-type gold deposit is a kind that both the ore-forming mechanism and ore-controlling factors are closely related to the ductile shear zone and its evolution. Ductile shear zone develops in Beishan area, Gansu of Northwest China, and develops especially well in the south belt. The controls of the ductile shear zone on gold deposits are as follows. (1) The regional distribution of gold deposits (and gold spots) is controlled by the ductile shear zone. (2) The ductile-brittle shear zone is formed in the evolution process of ductile shear zone and both are only ore-bearing structures and control the shape, attitude, scale, and distribution of mineralization zones and ore-bodies. (3) Compresso-shear ductile deformation results in that the main kind of gold mineralization is altered mylonite type and the main alteralization is metasomatic. (4) Ore-bearing fracture systems are mainly P-type ones, some D-type and R-type ones, but only individual R'-type and T-type ones. (5) Dynamic differen- tiation and dynamic metamorphic hydrothermal solution resulting from ductile deformation is one of the sources of ore-forming fluid of gold mineralization, and this is identical with that ore-forming materials are mainly from metamorphic rocks, and ore-forming fluid is mainly composed of metamorphic water, and with the fluid inclusion and geo-chemical characteristics of the deposit. (6) There is a negative correlation between the gold abundance and susceptibility anlsotropy (P) of the altered mylonlte samples from the deposit, which shows that the gold mineralization is slightly later than the structural deformation. All above further expound the ore-forming model of the ductile shear zone type of gold deposits.
文摘Warm and humid climate and gentle hilly topography have provided favourable conditions for the devel-opment of the weathering crust of the granite intrusions in the Longnan area, Jiangxi Province. REE is mostlyconcentrated in an adsorption state in clay in the wholly weathered zone. The rare-earth minerals enriched inthe parent rocks provided the source material for the REE enrichment. Exchangeable REE accounts for48-86%. Extraction experiments and stable isotopic study of clay minerals suggest that the downward infiltra-tion of meteoric water and increasing gradient of pH values have played an important role in the enrichment ofREE during the progressive weathering. Slight fractionation of individual REE can not change their distribu-tion patterns in the profiles. which are inherited from the parent rocks.
基金Supported by Special Project for Preceding Study of 973 Program"Stability Research of Tall Barchan Dune at Oasis Fringe(2014CB460611)National Natural Science Foundation of China"Climatic and Environmental Factors for Formation of Sand Sediment Zone and Its Ecological Effects at Minqin Oasis Fringe of Gansu Province(41261102)
文摘[Objective] The paper was to discuss why the top of tall barchan dunes and barchan chains widespread in single prevailing wind area had not been leveled by wind erosion. [Method] Based on the preliminary survey of distribution status,the morphological characteristics and environmental conditions of barchan dunes and barchan chains in Hexi desert area of Gansu were investigated in details. The significance of difference between samples and significance of correlation between indicators were examined via variance test. [Result] Barchan dunes and barchan chains in Hexi desert area of Gansu distributed at the leeward direction of desert fringe,generally in patch distribution. The distribution area was gravelly beach or cohesive gravel beach,with broader dune slack; winds in distribution area of barchan dunes and barchan chains blew obviously from one direction,while winds at other directions were light or occasionally strong but with low frequency;the barchan dune in the desert fringe of Hexi desert area of Gansu was relatively tall,while barchan chain was even more taller and larger. Coincidence or separation of the dune peak and the sand ridge might be related to distribution frequency of dominant prevailing wind or wind at opposite direction and the observation seasons.[Conclusion]Studying top stability of barchan dune has an important academic value in revealing blowing sand movement rule at desert fringe,invasion of sand flow,and expansion of desert.
基金sponsored by the State Key Laboratory of Geodesy and Earth’s Dynamics,Institute of Geodesy and Geophysics,Chinese Academy of Sciences(SKLGED2018-4-1-E)China MOST 973 Program(2014CB845901)
文摘The 2008 Wenchuan earthquake has a significant impact on the seismicity of nearby regions. The Longnan earthquake which occurred on September 12,2008 in Gansu Province was out of the aftershock zone. Reliable source parameters are essential for understanding the seismogenic process of this earthquake. Therefore,three approaches are adopted to study the source parameters of this event. The focal mechanism is obtained with the g CAP method that takes non-Double-Couple(non-DC)component into account. The two fault planes are NP1:150°/45°/81° and NP2:342°/45°/98°,while the non-DC component is about 53%. The focal depth is 1. 6 km,which indicates the Longnan earthquake is a shallow event. Furthermore,this result is also in good agreement with results obtained with two other approaches:amplitude spectra of Rayleigh wave and surface displacement from In SAR measurement. To analyze the cause of the event,coulomb failure stress change caused by the Wenchuan earthquake on the Longnan earthquake fault plane is calculated. The result shows that coulomb stress change is 30 k Pa around the Longnan earthquake hypocenter,which exceeds the typical triggering threshold of 10 k Pa. The research indicates that the Wenchuan earthquake probably promote the happening of the Longnan earthquake.
基金supported by the National Natural Science Foundation of China (No. 41174034)
文摘The firework algorithm(FWA) is a novel swarm intelligence-based method recently proposed for the optimization of multi-parameter, nonlinear functions. Numerical waveform inversion experiments using a synthetic model show that the FWA performs well in both solution quality and efficiency. We apply the FWA in this study to crustal velocity structure inversion using regional seismic waveform data of central Gansu on the northeastern margin of the Qinghai-Tibet plateau. Seismograms recorded from the moment magnitude(MW) 5.4 Minxian earthquake enable obtaining an average crustal velocity model for this region. We initially carried out a series of FWA robustness tests in regional waveform inversion at the same earthquake and station positions across the study region,inverting two velocity structure models, with and without a low-velocity crustal layer; the accuracy of our average inversion results and their standard deviations reveal the advantages of the FWA for the inversion of regional seismic waveforms. We applied the FWA across our study area using three component waveform data recorded by nine broadband permanent seismic stations with epicentral distances ranging between 146 and 437 km. These inversion results show that the average thickness of the crust in this region is 46.75 km, while thicknesses of the sedimentary layer, and the upper, middle, and lower crust are 3.15,15.69, 13.08, and 14.83 km, respectively. Results also show that the P-wave velocities of these layers and the upper mantle are 4.47, 6.07, 6.12, 6.87, and 8.18 km/s,respectively.
基金Supported by Science and Technology Innovation Project of Gansu Province(2009GAAS38)
文摘Caligula Japonica has continuously broken out in large scale in Longnan City, Gansu Province of China, causing heavy economic losses. In order to ef- fectively control the insect and to increase the production benefit of walnut in Longnan, the authors have investigated and observed the morphological characters and living habits of C. Japonica. The major causes of continuous large-scale occurrence of C. Japonica in Longnan City are analyzed concretely, and the integrated con- trol measures are put forward from the aspects of silvicultural measures, physical control, chemical control and biological control.
基金funded by China Geological Survey (grant no.1212011120899)the Department of Geology & Mining, China National Nuclear Corporation (grant no.201498)
文摘Hyperspectral remote sensing is now a frontier of the remote sensing technology. Airborne hyperspectral remote sensing data have hundreds of narrow bands to obtain complete and continuous ground-object spectra. Therefore, they can be effectively used to identify these grotmd objects which are difficult to discriminate by using wide-band data, and show much promise in geological survey. At the height of 1500 m, have 36 bands in visible to the CASI hyperspectral data near-infrared spectral range, with a spectral resolution of 19 nm and a space resolution of 0.9 m. The SASI data have 101 bands in the shortwave infrared spectral range, with a spectral resolution of 15 nm and a space resolution of 2.25 m. In 2010, China Geological Survey deployed an airborne CASI/SASI hyperspectral measurement project, and selected the Liuyuan and Fangshankou areas in the Beishan metallogenic belt of Gansu Province, and the Nachitai area of East Kunlun metallogenic belt in Qinghai Province to conduct geological survey. The work period of this project was three years.
基金Supported by the Project of Research on Risk Division of Characteristic Agricultural Meteorological Disasters and Climatic Regionalization in Longnan Mountainous Areas(2013-20)
文摘Based on the observation data of temperature in Chengxian meteorological station( the climate representative station of Longnan City,Gansu Province) during 1961-2014,the annual,seasonal and monthly changes of temperature were analyzed,and the abrupt changes in relevant variables were tested using the cumulative anomaly method. The results showed that annual average temperature in Chengxian County increased by 0. 138 ℃/10 a in the past 54 years. There was an obvious sudden change in annual average temperature around 1996. The annual average temperature showed a downward trend before 1996 and an upward trend after 1996. Average temperature in spring,summer,autumn and winter increased by 0. 113,0. 028,0. 157 and 0. 259 ℃/10 a respectively. The fluctuation of average temperature in spring and winter was the largest,followed by summer,while the fluctuation was the smallest in autumn. There were certain differences between various seasons in terms of the years with sudden changes in average temperature,which was not consistent with the years with the sudden changes in annual average temperature. The changing rate of monthly average temperature was the largest in February( up to 0. 412 ℃/10 a),followed by March,April and November,but it was the smallest in May( only 0. 005 ℃/10 a). The maximum of monthly average temperature appeared mostly in the 21 stcentury,while the minimum appeared in the 20 thcentury.
文摘The Gansu Rare Earth Corporation(GREC)which has fixed assetsof about RMB 100 million yuan is the largest RE enterprise in Asia.GREC is affiliated to the China National Nonferrous Metals In-dustry Corporation and is located in Baiyin city, Gansu province, P.R.China, covering a area of 105 ha.GREC is a corporation integrating technology, industry and trade.GREC provides a complete RE production, a production covering frommining, ore-dressing to metallurgy. Besides the mining and ore-dres-sing plants jointly managed in Jiangxi, Sichuan and Fujian provinces,
文摘Two Mesozoic intramontane basins are developed in the Dunhuang-Yumenguan-Jiuquan area of Gansu Province,China,i.e.,the Gongpoquan Basin(E97°30′-98°10′,N41°30′-41°45′)and the Yujingzi Basin(E98°15′-99°00′,N40°15'-40°40')(Fig.1).A large number of dinosaurs and other fossils have been discovered in these two basins,which are called dinosaur'tribes'by paleontologists.
文摘In the last few years, Gansu Province hasmade a great effort to perfect itsinfrastructure in terms of highways,airports, posts and telecommunications andrailways, aiming at increasing foreigninvestment in Gansu. The Preferential Methodsfor More Foreign Investment of GansuProvince, which were revised recently, isalso part of the effort. The Preferential Methods for MoreForeign Investment, issued by the GansuProvincial Government in 1992, have had
文摘Gansu, situated at the juncture of theQingzang Plateau, Inner MongoliaPlateau and loess plateau, with aterritory of 454,000 square kilometres, isbounded by Inner Mongolia, Shaanxi, Ningxia,Xinjiang, Qinghai and Sichuan. It even sharesa short border with Mongolia. There are 41nationalities, about 24.3795 million people,inhabiting the five municipalities under thejurisdiction of Gansu. There are also sevenprefectures and two ethnic group