The proposed site of the Diamer Bhasha Dam in northern Pakistan is situated in an active tectonic zone with intensive seismicity,which makes it necessary for seismic hazard analysis(SHA).Deterministic and probabilisti...The proposed site of the Diamer Bhasha Dam in northern Pakistan is situated in an active tectonic zone with intensive seismicity,which makes it necessary for seismic hazard analysis(SHA).Deterministic and probabilistic approaches have been used for SHA of the dam site.The Main Mantle Thrust(MMT),Main Karakaram Thrust(MKT),Raikot-Sassi Fault(RKSF)and Kohistan Fault(KF)have been considered as major seismic sources,all of which can create maximum ground shaking with maximum potential earthquake(MPE).Deterministically estimated MPE for magnitudes of 7.8,7.7,7.6,and 7.1 can be produced from MMT,MKT,RKSF and KF,respectively.The corresponding peak ground accelerations(PGA)of 0.07,0.11,0.13 and 0.05 g can also be generated from these earthquakes,respectively.The deterministic analysis predicts a so-called floating earthquake as a MPE of magnitude=7.1 as close as 10 km away from the site.The corresponding PGA was computed as 0.38 g for a maximum design earthquake at the project site.However,the probabilistic analysis revealed that the PGA with 50%probability of exceedance in 100 years is 0.18 g.Thus,this PGA value related to the operational basis earthquake(OBE)is suggested for the design of this project with shear wave velocity(V_(s30))equal to 760 m/s under dense soil and soft rock conditions.展开更多
In recent decades, the migration rates of the large cities of Punjab have been risen up to a considerable level due to the lack of employment opportunities as well as lack of facilities in the rural areas of the provi...In recent decades, the migration rates of the large cities of Punjab have been risen up to a considerable level due to the lack of employment opportunities as well as lack of facilities in the rural areas of the province. It has caused an unprecedented and unplanned urbanization across the urban areas of the province. This study has been undertaken to perform fractal analysis about the sprawl in rapidly growing city. GIS and remote sensing data have been used in this study as an emerging technology which is cost effective as well as accurate at the same time. Landsat images have been taken for the study and the sprawl has been calculated with the analysis of the data of each decade for past more than 40 years. It has been observed that the built up area is 47.8 to 141.12 Sq. Km whereas the pattern of urban settlement has been classified as clustered and linear, following the roads network. The temporal population growth also seconded these results. The population growth rate and population density increase, are based on the pixel based extraction of the data from satellite imagery for the period of 2000 to 2014, which is taken as a decision support tool. In 2000, the population of the district increased from 2,071,694 (1981 census) to 2,939,907 and then in 2013, it became 4,384,191 at a rate to 2.93% upturn per annum. Moreover, the study also reveals the extent of the growth of other land uses as well which may be taken as a reference that in an agricultural country like Pakistan, the natural resources are being wasted (by urbanization of the fertile land). There must be some master planning to avoid such things in the other cities as well.展开更多
文摘The proposed site of the Diamer Bhasha Dam in northern Pakistan is situated in an active tectonic zone with intensive seismicity,which makes it necessary for seismic hazard analysis(SHA).Deterministic and probabilistic approaches have been used for SHA of the dam site.The Main Mantle Thrust(MMT),Main Karakaram Thrust(MKT),Raikot-Sassi Fault(RKSF)and Kohistan Fault(KF)have been considered as major seismic sources,all of which can create maximum ground shaking with maximum potential earthquake(MPE).Deterministically estimated MPE for magnitudes of 7.8,7.7,7.6,and 7.1 can be produced from MMT,MKT,RKSF and KF,respectively.The corresponding peak ground accelerations(PGA)of 0.07,0.11,0.13 and 0.05 g can also be generated from these earthquakes,respectively.The deterministic analysis predicts a so-called floating earthquake as a MPE of magnitude=7.1 as close as 10 km away from the site.The corresponding PGA was computed as 0.38 g for a maximum design earthquake at the project site.However,the probabilistic analysis revealed that the PGA with 50%probability of exceedance in 100 years is 0.18 g.Thus,this PGA value related to the operational basis earthquake(OBE)is suggested for the design of this project with shear wave velocity(V_(s30))equal to 760 m/s under dense soil and soft rock conditions.
文摘In recent decades, the migration rates of the large cities of Punjab have been risen up to a considerable level due to the lack of employment opportunities as well as lack of facilities in the rural areas of the province. It has caused an unprecedented and unplanned urbanization across the urban areas of the province. This study has been undertaken to perform fractal analysis about the sprawl in rapidly growing city. GIS and remote sensing data have been used in this study as an emerging technology which is cost effective as well as accurate at the same time. Landsat images have been taken for the study and the sprawl has been calculated with the analysis of the data of each decade for past more than 40 years. It has been observed that the built up area is 47.8 to 141.12 Sq. Km whereas the pattern of urban settlement has been classified as clustered and linear, following the roads network. The temporal population growth also seconded these results. The population growth rate and population density increase, are based on the pixel based extraction of the data from satellite imagery for the period of 2000 to 2014, which is taken as a decision support tool. In 2000, the population of the district increased from 2,071,694 (1981 census) to 2,939,907 and then in 2013, it became 4,384,191 at a rate to 2.93% upturn per annum. Moreover, the study also reveals the extent of the growth of other land uses as well which may be taken as a reference that in an agricultural country like Pakistan, the natural resources are being wasted (by urbanization of the fertile land). There must be some master planning to avoid such things in the other cities as well.
