Surface mining activities may introduce damages to nearby infrastructure. Concerns are put forward by the power company about structural integrity of electric power transmission structures in areas where coal mining a...Surface mining activities may introduce damages to nearby infrastructure. Concerns are put forward by the power company about structural integrity of electric power transmission structures in areas where coal mining activities cause strong ground vibrations. Common practice in the power industry is to limit ground motion by specifying maximum Peak Particle Velocity. So far, there is a lack of industry-wide recognized guidelines on how ground vibration limits should be set for the transmission structures. In order to develop a defense strategy to protect power transmission lines against strong ground motions in mining areas, a systematic research work was conducted to establish strong ground vibration characteristics and to study impacts of ground excitations on transmission pole structures. Ground movements were recorded using geophones and wireless tri-axial sensing units. The process of generating ground motion response spectra via analyzing actual ground motion measurements is described in the paper. These spectra developed based on peak particle velocities were used as a basis for spectral analysis performed using validated Finite Element models to obtain structural displacements, reactions and stress states of the transmission pole structures in the mining sites. A quantitative ground motion limit was established by comparing structural responses with the corresponding design requirements.展开更多
Interdecadal and interannuat variations of saline-alkali land area in Qian'an County, Jilin Province, China were comprehensively analyzed in this paper by means of satellite remote sensing interpretation, field flux ...Interdecadal and interannuat variations of saline-alkali land area in Qian'an County, Jilin Province, China were comprehensively analyzed in this paper by means of satellite remote sensing interpretation, field flux observations and regional climate diagnosis. The results show that on the interannual scale, the impact of climate factors accounts for 71.6% of the total variation of the saline-alkali land area, and that of human activities accounts for 28.4%. Therefore the impact of climate factors is obviously greater than that of human activities. On the interdecadal scale, the impact of climate factors on the increase of the saline-alkali land area accounts for 43.2%, and that of human activities accounts for 56.8%. The impact of human activities on the variation of saline-alkali land area is very clear on the interdecadal scale, and the negative impact of human activities on the environment should not be negligible. Besides, changes in the area of heavy saline-alkali land have some indication for development of saline-alkali land in Qian'an County.展开更多
Purpose: The purpose of this study was to examine the effects of landing kinematics and electromyographic (EMG) activities of medial gastrocnemius on a combined inversion and plantarflexion surface on the ankle (M...Purpose: The purpose of this study was to examine the effects of landing kinematics and electromyographic (EMG) activities of medial gastrocnemius on a combined inversion and plantarflexion surface on the ankle (MG), peroneus longus (PL), and tibialis anterior (TA) muscles. Methods: Twelve recreational athletes performed five drop landings from an overhead bar of 30 cm height on to three surfaces: a flat surface, a 25° inversion surface, and a combined surface of 25° inversion and 25° plantarflexion. The kinematic variables and integrated EMG (IEMG) of the three muscles were assessed using a one-way repeated measures ANOVA and a 3 × 3 (surface × muscle) ANOVA, respectively (p 〈 0.05). Results: The IEMG results showed a significant muscle by surface interaction. The flat surface induced higher TA activity than the two tilted surfaces. The inverted surface produced significantly higher inversion peak angle and velocity than the flat surface, but similar PL activity across the surfaces. The MG IEMG, ankle plantarflexion angle, and inversion range of motion were significantly higher for the combined surface compared to the inverted surface. Conclusion: These findings suggest that compared to the inversion surface, the combined plantarflexion and inversion surface seems to provide a more unstable surface condition for lateral ankle sprains during landing.展开更多
A method of forecasting total seismic energy induced by longwall exploitation, based on changes in ground subsidence, is presented in the form of a linear regression model with one with one independent variable. In th...A method of forecasting total seismic energy induced by longwall exploitation, based on changes in ground subsidence, is presented in the form of a linear regression model with one with one independent variable. In the method, ground subsidence is described with a cross-section area of a subsidence trough Pw along a line of observations in the direction of an advancing longwall front, approximately along the axis of the longwall area. Total seismic energy is determined on the basis of seismic energy data of tremors induced by exploitation. The presentation consists of a detailed method and evaluation of its predictive ability for the area of longwall exploitation within the region of one of the coal mines in the Upper Silesian Coal Basin. This method can be used for forecasting the total seismic energy released by tremors within the area directly connected with the exploitation, in which the seismic activity induced by this exploitation occurs. The estimation of the parameters of the determined model should each time be carried out with investigations of the correctness of the model. The method cannot be applied when the number of recorded phenomena is small and when there is insufficient data to make it possible to calculate the index Pw.展开更多
Fractal geometry is increasingly becoming a useful tool for modeling and quantifying the complex patterns of natural phenomena. The Earth's topography is one of these phenomena that have fractal characteristics. T...Fractal geometry is increasingly becoming a useful tool for modeling and quantifying the complex patterns of natural phenomena. The Earth's topography is one of these phenomena that have fractal characteristics. This paper investigates the relative sensitivity of topography to active tectonics using ASTER Global Digital Elevation Model. The covering divider method was used for direct extraction of surface fractal dimension(D surf) to estimate the roughness-surface of topography with aid of geographic information system(GIS)techniques. This evaluation let us highlight the role of the geomorphic and tectonic processes on the spatial variability of fractal properties of natural landforms.Geomorphic zones can be delineated using fractal dimension mapping in which variability of surface fractal dimension reflects the roughness of the landform surface and is a measure of topography texture. Obtained results showed this method can be a quick and easy way to assess the distribution of land surface deformation in different tectonic settings. The loose alluvial deposits and irregularities derived by tectonic activity have high fractal dimensions whereas the competent formations and higher wavelength folded surfaces have lower fractal dimensions.According to the obtained results, the Kazerun Fault Zone has a crucial role in the separation of the Zagros Mountain Ranges into the different lithological,geomorphological and structural zones.展开更多
About 75% water-inrush accidents in China are caused by geological structure such as faults, therefore, it is necessary to investigate the water-inrush mechanism of faults to provide references for the mining activity...About 75% water-inrush accidents in China are caused by geological structure such as faults, therefore, it is necessary to investigate the water-inrush mechanism of faults to provide references for the mining activity above confined water. In this paper, based on the fluid-solid coupling theory, we built the stress-seepage coupling model for rock, then we combined with an example of water-inrush caused by fault, studied the water-inrush mechanism by using the numerical software COMSOL Mutiphysics, analyzed the change rule of shear stress, vertical stress, plastic area and water pressure for stope with a fault, and estimated the water-inrush risk at the different distances between working faces and the fault. The numerical simula- tion results indicate that: (1) the water-inrush risk will grow as the decrease of the distance between working face and the fault; (2) the failure mode of the rock in floor with fault is shear failure; (3) the rock between water-containing fault and working face failure is the reason for water-inrush.展开更多
Human activity could be changing the Earth's foundations themselves, as we affect multiple systems interacting in feedback mechanisms changing the atmosphere, hydrosphere, cryosphere, biosphere, and even the lithosph...Human activity could be changing the Earth's foundations themselves, as we affect multiple systems interacting in feedback mechanisms changing the atmosphere, hydrosphere, cryosphere, biosphere, and even the lithosphere (solid surface) and asthenosphere (deformable semi-molten rock layer beneath). Anthropogenic movement of ice, water and sediment alters viscosity and movement of the asthenosphere; this induces earthquakes, tsunamis, volcanism and rifting, and may induce plate-tectonic-change. These processes may account for the timing of unexplained contemporary Icelandic, New Zealand, Chilean, Japanese and Indonesian seismicity, volcanism and magma movement. Climate-change and sea-level rise are creating: slip-planes from differential water pore-pressures and/or weakening of previous fault-planes; sediment-change and altered hydrology and reservoir-mass, inducing isostasy and further change in pore-pressure. Loss of plant biomass and diversity alter hydrology, precipitation and transpiration, causing isostasy and further sediment- and climate-change. Increased ocean-mass, temperatures and acidity, reduced oceanic oxygenation, and increased transport of (organic) sediments elevate the production and destabilisation of gas-hydrates, causing slumps and tsunamis. Isostasy and altered viscosity of the asthenosphere increase seismicity, slope and faulting, which are the prime triggers for slumping and tsunamis. Altered asthenosphere flows hasten subduction and rifting landward of subduction, enhancing volcanism. All of these processes predominantly coincide, temporally and spatially, in the coasts and continental margins, and the Pacific ring-of-fire, although response times and extents may vary from immediate to multi-millennial scales and from negligible to catastrophic. Contemporary Icelandic seismic and volcanic activity is explained by depleted magma reserves on the north-western side of the mid-ocean ridge as asthenosphere moves from the constructive boundary under deglaciating and rising Greenland.展开更多
A major natural hazard associated with LGOM (Legnica-Glogow Copper Mining) mining is the dynamic phenomena occurrence, physically observed as seismic tremors. Some of them generate effects in the form of relaxations...A major natural hazard associated with LGOM (Legnica-Glogow Copper Mining) mining is the dynamic phenomena occurrence, physically observed as seismic tremors. Some of them generate effects in the form of relaxations or bumps. Long-term observations of the rock mass behaviour indicate that the degree of seismic hazard, and therefore also seismic activity in the LGOM area, is affected by the great depth of the copper deposit, high-strength rocks as well as the ability of rock mass to accumulate elastic energy. In this aspect, the effect of the characteristics of initial stress tensor and the orientation of considered mining panel in regards to its components must be emphasised. The primary objective of this study is to answer the question, which of the factors considered as "influencing" the dynamic phenomena occurrence in copper mines have a statistically significant effect on seismic activity and to what extent. Using the general linear model procedure, an attempt has been made to quantify the impact of different parameters, including the depth of deposit, the presence of goaf in the vicinity of operating mining panels and the direction of mining face advance, on seismic activity based on historical data from 2000 to 2010 concerned with the dynamic phenomena recorded in different mining panels in Rudna mine. The direction of mining face advance as well as the goaf situation in the vicinity of the mining panel are of the greatest interest in the case of the seismic activity in LGOM. It can be assumed that the appropriate manipulation of parameters of mining systems should ensure the safest variant of mining method under specific geological and mining conditions.展开更多
Abstract On the basis of subsidence history analysis and balanced cross-section analysis, the vertical uplift/subsidence history and horizontal extension/compression history of the north depression of the south Yellow...Abstract On the basis of subsidence history analysis and balanced cross-section analysis, the vertical uplift/subsidence history and horizontal extension/compression history of the north depression of the south Yellow Sea basin are quantitatively studied. The results show that the tectonic evolution of the north depression of the south Yellow Sea basin since late Cretaceous can be divided into a rifting phase (late Cretaceous to Paleogene) and a post-rifting phase (Neogene to Quaternary). The rifting phase can be further subdivided into an initial rifting stage (late Cretaceous), an intensive rifting stage (Paleocene), a rifting termination stage (Eocene), and an inversion-uplifting stage (Oligocene). Together, this division shows the characteristics of an episodic-evolved intracontinental rift-depression basin. The deformation of the north depression of the south Yellow Sea basin since late Cretaceous was mainly fault-related. The horizontal extension and tectonic subsidence were controlled by the activity of faults. The differential evolution of faults also caused variations in local uplift/subsidence movements and the regional heterogeneity in extension. The late Cretaceous initial rifting of the north depression of the south Yellow Sea basin is related to the Pacific-Eurasia convergence. From the Paleocene intensive rifting stage to present, the Pacific-Eurasia convergence and India-Eurasia convergence have played important roles in the evolution of this region.展开更多
For the last two decades the world has undergone a population explosion which has been accompanied by a speeding up of urbanization and land use for industrial and agricultural products. These involve a vast increase ...For the last two decades the world has undergone a population explosion which has been accompanied by a speeding up of urbanization and land use for industrial and agricultural products. These involve a vast increase in the discharge of pollutants into very different receiving water bodies, and have had adverse effects on the various components of the environment. For a long time, human has concerned a little of the natural environment. It is obvious that this variation in surface temperature of the earth increases the level of sea due to snowmelt. So climate change is manifested by many phenomena: floods, droughts, fires, tornadoes, cyclones, earthquakes, volcanic eruptions, diseases etc.. The statement today is dramatic. Entire regions were devastated and many rivers and lakes have become polluted around the world. Pollution has it nature which is hard to be absorbed. Where did the different pollutants come from? What are the risks to the aquatic environment? To prevent and combat the general decline of these ecosystems, it is important to distinguish and determine the effects of different sources of pollution and any changes that may suffer the physical environment. The climate depends primarily on changes in earth orbit parameters, which affect the solar radiation received by the earth surface. Therefore, human participates strongly to these changes, for example, pollution is the main reason to argue the greenhouse effect, an increase of anthropogenic carbon dioxide (CO2) into the atmosphere, which promotes global warming to the planet. These modifications are already applied in order to ensure durable development in water resources by controlling discharges into streams to preserve water resources for future generations and to ensure reconciliation between man-climate and environment.展开更多
The East Kuulun active fault zone, which lies in the valley of the Kuulun Mountains above an elevation of 4,000 meters, is an important active fault zone in the Northeast Qinghai-Xizang (Tibet) Plateau. The 1937, th...The East Kuulun active fault zone, which lies in the valley of the Kuulun Mountains above an elevation of 4,000 meters, is an important active fault zone in the Northeast Qinghai-Xizang (Tibet) Plateau. The 1937, the Tosonhu lake Ms7. 5 earthquake occurred in the eastern segment of the East Kuulun active fault zone. Four field investigations were launched on this seism in 1963, 1971, 1980, and between 1986 and 1990. However, due to different extents of the investigations, four different conclusions have been gained. Concerning the length aspect of the surface rupture zone of this earthquake, the unanimous consensus is that its eastern end lies in the west side of the main Ridge of the A 'nyemaqen Mountains, but opinions about the western end and the location of the macro-epicenter are different. Based on investigation and comprehensive study, a series of scientific problems like geometric and kinetic characteristics, the length of the rupture zone, the maximum sinistral horizontal displacement and the macroepicenter were re-evaluated. We believe that the total length of this earthquake's surface deformation zone is at least 240km; the western end of the zone is at the west of Wnsuwuwoguole; the maximum sinistral horizontal displacement is 8m to the west of Baerhalasha gully on the east side of Sanchakou; the maximum vertical displacement is 3.5m in the south of Sanchakou and the macro-epicenter is in Sanchakou.展开更多
文摘Surface mining activities may introduce damages to nearby infrastructure. Concerns are put forward by the power company about structural integrity of electric power transmission structures in areas where coal mining activities cause strong ground vibrations. Common practice in the power industry is to limit ground motion by specifying maximum Peak Particle Velocity. So far, there is a lack of industry-wide recognized guidelines on how ground vibration limits should be set for the transmission structures. In order to develop a defense strategy to protect power transmission lines against strong ground motions in mining areas, a systematic research work was conducted to establish strong ground vibration characteristics and to study impacts of ground excitations on transmission pole structures. Ground movements were recorded using geophones and wireless tri-axial sensing units. The process of generating ground motion response spectra via analyzing actual ground motion measurements is described in the paper. These spectra developed based on peak particle velocities were used as a basis for spectral analysis performed using validated Finite Element models to obtain structural displacements, reactions and stress states of the transmission pole structures in the mining sites. A quantitative ground motion limit was established by comparing structural responses with the corresponding design requirements.
基金Under the auspices of National Key Technology R&D Program of China (No. 2007BAC29B01)Major State Basic Research Development Program of China (973 Program) (No. 2006CB400500)+1 种基金National Natural Science Foundation of China (No.40575047, 40705036, 40975055)Key Program of Jilin Provincial Science & Technology Department (No. 20020417)
文摘Interdecadal and interannuat variations of saline-alkali land area in Qian'an County, Jilin Province, China were comprehensively analyzed in this paper by means of satellite remote sensing interpretation, field flux observations and regional climate diagnosis. The results show that on the interannual scale, the impact of climate factors accounts for 71.6% of the total variation of the saline-alkali land area, and that of human activities accounts for 28.4%. Therefore the impact of climate factors is obviously greater than that of human activities. On the interdecadal scale, the impact of climate factors on the increase of the saline-alkali land area accounts for 43.2%, and that of human activities accounts for 56.8%. The impact of human activities on the variation of saline-alkali land area is very clear on the interdecadal scale, and the negative impact of human activities on the environment should not be negligible. Besides, changes in the area of heavy saline-alkali land have some indication for development of saline-alkali land in Qian'an County.
文摘Purpose: The purpose of this study was to examine the effects of landing kinematics and electromyographic (EMG) activities of medial gastrocnemius on a combined inversion and plantarflexion surface on the ankle (MG), peroneus longus (PL), and tibialis anterior (TA) muscles. Methods: Twelve recreational athletes performed five drop landings from an overhead bar of 30 cm height on to three surfaces: a flat surface, a 25° inversion surface, and a combined surface of 25° inversion and 25° plantarflexion. The kinematic variables and integrated EMG (IEMG) of the three muscles were assessed using a one-way repeated measures ANOVA and a 3 × 3 (surface × muscle) ANOVA, respectively (p 〈 0.05). Results: The IEMG results showed a significant muscle by surface interaction. The flat surface induced higher TA activity than the two tilted surfaces. The inverted surface produced significantly higher inversion peak angle and velocity than the flat surface, but similar PL activity across the surfaces. The MG IEMG, ankle plantarflexion angle, and inversion range of motion were significantly higher for the combined surface compared to the inverted surface. Conclusion: These findings suggest that compared to the inversion surface, the combined plantarflexion and inversion surface seems to provide a more unstable surface condition for lateral ankle sprains during landing.
文摘A method of forecasting total seismic energy induced by longwall exploitation, based on changes in ground subsidence, is presented in the form of a linear regression model with one with one independent variable. In the method, ground subsidence is described with a cross-section area of a subsidence trough Pw along a line of observations in the direction of an advancing longwall front, approximately along the axis of the longwall area. Total seismic energy is determined on the basis of seismic energy data of tremors induced by exploitation. The presentation consists of a detailed method and evaluation of its predictive ability for the area of longwall exploitation within the region of one of the coal mines in the Upper Silesian Coal Basin. This method can be used for forecasting the total seismic energy released by tremors within the area directly connected with the exploitation, in which the seismic activity induced by this exploitation occurs. The estimation of the parameters of the determined model should each time be carried out with investigations of the correctness of the model. The method cannot be applied when the number of recorded phenomena is small and when there is insufficient data to make it possible to calculate the index Pw.
基金the Research Council of Shiraz University which has supported the project
文摘Fractal geometry is increasingly becoming a useful tool for modeling and quantifying the complex patterns of natural phenomena. The Earth's topography is one of these phenomena that have fractal characteristics. This paper investigates the relative sensitivity of topography to active tectonics using ASTER Global Digital Elevation Model. The covering divider method was used for direct extraction of surface fractal dimension(D surf) to estimate the roughness-surface of topography with aid of geographic information system(GIS)techniques. This evaluation let us highlight the role of the geomorphic and tectonic processes on the spatial variability of fractal properties of natural landforms.Geomorphic zones can be delineated using fractal dimension mapping in which variability of surface fractal dimension reflects the roughness of the landform surface and is a measure of topography texture. Obtained results showed this method can be a quick and easy way to assess the distribution of land surface deformation in different tectonic settings. The loose alluvial deposits and irregularities derived by tectonic activity have high fractal dimensions whereas the competent formations and higher wavelength folded surfaces have lower fractal dimensions.According to the obtained results, the Kazerun Fault Zone has a crucial role in the separation of the Zagros Mountain Ranges into the different lithological,geomorphological and structural zones.
基金Supported by the National Basic Research Program of China (2010CB226800) the National Natural Science Foundation of China (50904065) the Program for New Century Excellent Talents in University (NCET-09-0728)
文摘About 75% water-inrush accidents in China are caused by geological structure such as faults, therefore, it is necessary to investigate the water-inrush mechanism of faults to provide references for the mining activity above confined water. In this paper, based on the fluid-solid coupling theory, we built the stress-seepage coupling model for rock, then we combined with an example of water-inrush caused by fault, studied the water-inrush mechanism by using the numerical software COMSOL Mutiphysics, analyzed the change rule of shear stress, vertical stress, plastic area and water pressure for stope with a fault, and estimated the water-inrush risk at the different distances between working faces and the fault. The numerical simula- tion results indicate that: (1) the water-inrush risk will grow as the decrease of the distance between working face and the fault; (2) the failure mode of the rock in floor with fault is shear failure; (3) the rock between water-containing fault and working face failure is the reason for water-inrush.
文摘Human activity could be changing the Earth's foundations themselves, as we affect multiple systems interacting in feedback mechanisms changing the atmosphere, hydrosphere, cryosphere, biosphere, and even the lithosphere (solid surface) and asthenosphere (deformable semi-molten rock layer beneath). Anthropogenic movement of ice, water and sediment alters viscosity and movement of the asthenosphere; this induces earthquakes, tsunamis, volcanism and rifting, and may induce plate-tectonic-change. These processes may account for the timing of unexplained contemporary Icelandic, New Zealand, Chilean, Japanese and Indonesian seismicity, volcanism and magma movement. Climate-change and sea-level rise are creating: slip-planes from differential water pore-pressures and/or weakening of previous fault-planes; sediment-change and altered hydrology and reservoir-mass, inducing isostasy and further change in pore-pressure. Loss of plant biomass and diversity alter hydrology, precipitation and transpiration, causing isostasy and further sediment- and climate-change. Increased ocean-mass, temperatures and acidity, reduced oceanic oxygenation, and increased transport of (organic) sediments elevate the production and destabilisation of gas-hydrates, causing slumps and tsunamis. Isostasy and altered viscosity of the asthenosphere increase seismicity, slope and faulting, which are the prime triggers for slumping and tsunamis. Altered asthenosphere flows hasten subduction and rifting landward of subduction, enhancing volcanism. All of these processes predominantly coincide, temporally and spatially, in the coasts and continental margins, and the Pacific ring-of-fire, although response times and extents may vary from immediate to multi-millennial scales and from negligible to catastrophic. Contemporary Icelandic seismic and volcanic activity is explained by depleted magma reserves on the north-western side of the mid-ocean ridge as asthenosphere moves from the constructive boundary under deglaciating and rising Greenland.
文摘A major natural hazard associated with LGOM (Legnica-Glogow Copper Mining) mining is the dynamic phenomena occurrence, physically observed as seismic tremors. Some of them generate effects in the form of relaxations or bumps. Long-term observations of the rock mass behaviour indicate that the degree of seismic hazard, and therefore also seismic activity in the LGOM area, is affected by the great depth of the copper deposit, high-strength rocks as well as the ability of rock mass to accumulate elastic energy. In this aspect, the effect of the characteristics of initial stress tensor and the orientation of considered mining panel in regards to its components must be emphasised. The primary objective of this study is to answer the question, which of the factors considered as "influencing" the dynamic phenomena occurrence in copper mines have a statistically significant effect on seismic activity and to what extent. Using the general linear model procedure, an attempt has been made to quantify the impact of different parameters, including the depth of deposit, the presence of goaf in the vicinity of operating mining panels and the direction of mining face advance, on seismic activity based on historical data from 2000 to 2010 concerned with the dynamic phenomena recorded in different mining panels in Rudna mine. The direction of mining face advance as well as the goaf situation in the vicinity of the mining panel are of the greatest interest in the case of the seismic activity in LGOM. It can be assumed that the appropriate manipulation of parameters of mining systems should ensure the safest variant of mining method under specific geological and mining conditions.
文摘Abstract On the basis of subsidence history analysis and balanced cross-section analysis, the vertical uplift/subsidence history and horizontal extension/compression history of the north depression of the south Yellow Sea basin are quantitatively studied. The results show that the tectonic evolution of the north depression of the south Yellow Sea basin since late Cretaceous can be divided into a rifting phase (late Cretaceous to Paleogene) and a post-rifting phase (Neogene to Quaternary). The rifting phase can be further subdivided into an initial rifting stage (late Cretaceous), an intensive rifting stage (Paleocene), a rifting termination stage (Eocene), and an inversion-uplifting stage (Oligocene). Together, this division shows the characteristics of an episodic-evolved intracontinental rift-depression basin. The deformation of the north depression of the south Yellow Sea basin since late Cretaceous was mainly fault-related. The horizontal extension and tectonic subsidence were controlled by the activity of faults. The differential evolution of faults also caused variations in local uplift/subsidence movements and the regional heterogeneity in extension. The late Cretaceous initial rifting of the north depression of the south Yellow Sea basin is related to the Pacific-Eurasia convergence. From the Paleocene intensive rifting stage to present, the Pacific-Eurasia convergence and India-Eurasia convergence have played important roles in the evolution of this region.
文摘For the last two decades the world has undergone a population explosion which has been accompanied by a speeding up of urbanization and land use for industrial and agricultural products. These involve a vast increase in the discharge of pollutants into very different receiving water bodies, and have had adverse effects on the various components of the environment. For a long time, human has concerned a little of the natural environment. It is obvious that this variation in surface temperature of the earth increases the level of sea due to snowmelt. So climate change is manifested by many phenomena: floods, droughts, fires, tornadoes, cyclones, earthquakes, volcanic eruptions, diseases etc.. The statement today is dramatic. Entire regions were devastated and many rivers and lakes have become polluted around the world. Pollution has it nature which is hard to be absorbed. Where did the different pollutants come from? What are the risks to the aquatic environment? To prevent and combat the general decline of these ecosystems, it is important to distinguish and determine the effects of different sources of pollution and any changes that may suffer the physical environment. The climate depends primarily on changes in earth orbit parameters, which affect the solar radiation received by the earth surface. Therefore, human participates strongly to these changes, for example, pollution is the main reason to argue the greenhouse effect, an increase of anthropogenic carbon dioxide (CO2) into the atmosphere, which promotes global warming to the planet. These modifications are already applied in order to ensure durable development in water resources by controlling discharges into streams to preserve water resources for future generations and to ensure reconciliation between man-climate and environment.
基金the National Science Foundation (Grant No.40474037) and by the Special Programfor Early-stage Investigation of National Major Basic Research of the Ministry of Science and Technology,China (Grant No.JC200016)
文摘The East Kuulun active fault zone, which lies in the valley of the Kuulun Mountains above an elevation of 4,000 meters, is an important active fault zone in the Northeast Qinghai-Xizang (Tibet) Plateau. The 1937, the Tosonhu lake Ms7. 5 earthquake occurred in the eastern segment of the East Kuulun active fault zone. Four field investigations were launched on this seism in 1963, 1971, 1980, and between 1986 and 1990. However, due to different extents of the investigations, four different conclusions have been gained. Concerning the length aspect of the surface rupture zone of this earthquake, the unanimous consensus is that its eastern end lies in the west side of the main Ridge of the A 'nyemaqen Mountains, but opinions about the western end and the location of the macro-epicenter are different. Based on investigation and comprehensive study, a series of scientific problems like geometric and kinetic characteristics, the length of the rupture zone, the maximum sinistral horizontal displacement and the macroepicenter were re-evaluated. We believe that the total length of this earthquake's surface deformation zone is at least 240km; the western end of the zone is at the west of Wnsuwuwoguole; the maximum sinistral horizontal displacement is 8m to the west of Baerhalasha gully on the east side of Sanchakou; the maximum vertical displacement is 3.5m in the south of Sanchakou and the macro-epicenter is in Sanchakou.