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21.
Geotechnical and Geological Engineering - Shallow and deep seated landslides in natural slopes are often induced by rainfall. The cause of the failure is usually considered to be due to the...  相似文献   
22.
Using the lagged (past) climate indices, including El Nino–Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) as input parameters and long-term spring rainfall as outputs, calibration and validation of the linear multiple regression (MR) models have been performed. Since Australian rainfall varies both temporally and spatially, the analysis on the linear MR models was performed on regional scale. These models show the capability of linear MR technique for long-term predictions of Western Australian spring rainfall. The emphasis was given to assess the statistical correlations between Western Australian spring rainfall and dominating large-scale climate modes. The efficiency of linear modelling technique was evaluated to predict seasonal rainfall forecasting. At the same time, the Pearson correlation (R), mean absolute error, root-mean-square error and Willmott index agreement (d) were used to assess the capability of MR models. The models which fulfilled the limits of statistical significances were used for the prediction of future spring rainfall using independent data set. The results indicate that during calibration periods maximum achievable correlations varied from 0.47 to 0.53 for the selected stations. In regard to predict peaks and troughs of rainfall time series, it was found that correlations between predicted and actual peaks varied from 0.82 to 0.94 and between predicted and actual troughs varied from 0.53 to 0.91.  相似文献   
23.
The project area lies in the southern part of the Hazara Kashmir syntaxis. The Hazara Kashmir syntaxis is an antiformal structure. The project area includes Rumbli, Namb, Chatrora, Chachan, Panjar, Barathian and Utrinna areas of Rawalpindi and Sudhnoti districts. The southeastern limb of the Hazara Kashmir syntaxis is imbricated along Punjal thrust, Main Boundary thrust and Riasi fault. The Jhelum fault truncates the western limb of Hazara Kashmir syntaxis. The core of syntaxis comprises of Himalayan molasse deposits. These molasse deposits represent the part of cover sequence of Indian plate. These Himalayan molasse deposits include the Early to Middle Miocene Kamlial Formation, Middle to Late Miocene Chinji Formation, Late Miocene Nagri Formation and Late Miocene Dhok Pathan Formation. The area is highly deformed resulting folds and faults. The major folds in the project area are the Panjar anticline, Barathian syncline, Barathian anticline, Rumbli anticline, Chatrora antiformal syncline and Namb syncline. The folds are either northwest-southeast trending or southwestnortheast trending. The folds are asymmetric, open, and gentle and close in nature. The folds are southwest, northeast or southeast vergent. The Jhelum fault truncates the northeast and northwest trending structures. The folds and faults are the result of northeastsouthwest or northwest-southeast Himalayan compression.  相似文献   
24.
Li  Zhenya  Ali  Zulfiqar  Cui  Tong  Qamar  Sadia  Ismail  Muhammad  Nazeer  Amna  Faisal  Muhammad 《Natural Hazards》2022,111(1):547-566
Natural Hazards - The increase of frequency and severity of extreme weather events due to climate change gives evidence of severe challenges faced by infrastructure systems. Among them, the...  相似文献   
25.
Natural Hazards - Karachi is Pakistan’s largest city with population exceeding 18 million and is amongst the top five most congested cities in the world. Karachi has experienced no earthquake...  相似文献   
26.

The Uromia–Dokhtar Magmatic Arc (UDMA) is a northwest–southeast trending magmatic belt which is formed due to oblique subduction of Neotethys underneath Central Iran and dominantly comprises magmatic rocks. The Jebal-e-Barez Plutonic Complex (JBPC) is located southeast of the UDMA and composed of quartz diorite, granodiorite, granite, and alkali granite. Magmatic enclaves, ranging in composition from felsic to mafic, are abundant in the studied rocks. Based on the whole rock and mineral chemistry study, the granitoids are typically medium-high K calc-alkaline and metaluminous to peraluminous that show characteristics of I-type granitoids. The high field strength (HFS) and large ionic radius lithophile (LIL) element geochemistry suggests fractional crystallization as a major process in the evolution of the JBPC. The tectonomagmatic setting of the granitoids is compatible with the arc-related granitic suite, a pre-plate collision granitic suite, and a syncollision granitic suite. Field observations and petrographic and geochemical studies suggest that the rocks in this area are I-type granitoids and continental collision granitoids (CCG), continental arc granitoids (CAG), and island arc granitoid (IAG) subsections. The geothermobarometry based on the electron probe microanalysis of amphibole, feldspars, and biotite from selected rocks of JBPC implies that the complex formed at high-level depths (i.e., 9–12 km; upper continental crust) and at temperatures ranging from 650 to 750 °C under oxidation conditions. It seems that JBPC is located within a shear zone period, and structural setting of JBPC is extensional shear fractures which are product of transpression tectonic regime. All available data suggested that these granitoids may be derived from a magmatic arc that was formed by northeastern ward subduction of the Neotethyan oceanic crust beneath the Central Iran in Paleogene and subsequent collision between the Arabian and Iranian plates in Miocene.

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27.
Aziz  Asad  Anwar  Muhammad Mushahid  Dawood  Muhammad 《GeoJournal》2021,86(4):1915-1925

A strong need exists to increase the knowledge and recognize the values of neighborhood services. This paper makes an attempt to examine the impact of neighborhood services on land values, through analysis based on results obtained from multi linear regression analysis. This case study was done in area of dense urban settlement to check the consequence of neighborhood services through the hedonic pricing model base variables which include the structural, locational, community and neighborhood services. The regression coefficient was checked at (p?<?0.05) level of significance for each variable. The primary data was collect through the questionnaire filling by random sampling and Punjab Urban Gazette was used for the verification of land values in study area. The results found a valuable potential on land and property values of neighborhood services through the regression analysis results express through R (0.926), R2 (0.856) and coefficient tables to represent the effect of each individual variable on property and land values. Every individual variable play role in defining the values of land and property based upon its utilization such as larger the structure of a property, more the covered area, larger size of a property more the land area higher price. Similarly, for locational factor study in geography, a piece of land adjacent to the road have high land values 50–70% compare to those located at distance. Very less attention has been paid on such issues in the world due to lack of effective urban planning and research on such crucial issues. If empirical studies on such issue has been done, effective way can be obtained for urban planning.

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28.
A structural interpretation of the Ziarat block in the Balochistan region (a part of the Suleiman Fold and Thrust Belt) has been carried out using seismic and seismological data. Seismic data consists of nine 2.5D pre‐stack migrated seismic lines, whereas the seismological data covers the Fault Plane Solution and source parameters. Structural interpretation describes two broad fault sets of fore and back thrusts in the study area that have resulted in the development of pop‐up structures, accountable for the structural traps and seismicity pattern in terms of seismic hazard. Seismic interpretation includes time and depth contour maps of the Dungan Formation and Ranikot group, while seismological interpretation includes Fault Plane Solution, that is correlated with a geological and structural map of the area for the interpretation of the nature of the subsurface faults. Principal stresses are also estimated for the Ranikot group and Dungan Formation. In order to calculate anisotropic elastic properties, the parameters of the rock strength of the formations are first determined from seismic data, along with the dominant stresses (vertical, minimum horizontal, and maximum horizontal). The differential ratio of the maximum and minimum horizontal stresses is obtained to indicate optimal zones for hydraulic fracturing, and to assess the potential for geothermal energy reservoir prospect generation. The stress maps indicate high values towards the deeper part of the horizon, and low towards the shallower part, attributed to the lithological and structural variation in the area. Outcomes of structural interpretation indicate a good correlation of structure and tectonics from both seismological and seismic methods.  相似文献   
29.
Waste engine oil causes a vital environmental pollution when it spill during change and transportation and products of waste engine oil causes lethal effects to the living systems. Thus, abiotic and biotic approaches are being extensively used for removal of waste engine oil pollution. Therefore in present study, waste engine oil degradation was accomplished by a new bacterial culture, isolated from the soil by an enrichment technique. Morphological, biochemical and gene sequence analysis revealed that isolate was Bacillus cereus. Subsequently, biodegradation potential of B. cereus for waste engine oil was studied. Experimental variables, such as pH, substrate concentration, inoculum size, temperature and time on the biodegradation, were checked in mineral salt medium. The biodegradation efficiency of B. cereus was determined by gravimetry, UV–visible spectrophotometry and gas chromatography. In addition, waste engine oil was also characterized by GC–MS and FTIR for its major constituents, which showed total 38 components in waste engine oil, including hopanes, benzopyrene, long-chain aliphatic hydrocarbons, dibenzothiophenes, biphenyl and their derivatives. Results of successive biodegradation indicated that B. cereus was capable to degrade 1% of waste engine oil with 98.6% degradation potential at pH 7 within 20 days. Hence, B. cereus presents an innovative tool for removing the engine oil from the contaminated area.  相似文献   
30.
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