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361.
Ashraf Muhammad Arshad Adnan Patel Praharsh M. Khan Adeel Qamar Huma Siti-Sundari Ristina Ghani Muhammad Usman Amin Ali Babar Jamilur Rehman 《Natural Hazards》2021,109(3):2127-2151
Natural Hazards - Climate change-induced disasters show the highest risk for agriculture and livelihoods in rural areas of developing countries. Due to changing rainfall pattern, the arid and... 相似文献
362.
Mohsan Muhammad Kiyota Takashi Umar Muhammad Katagiri Toshihiko 《Geotechnical and Geological Engineering》2021,39(6):4523-4531
Geotechnical and Geological Engineering - This paper investigates the settlement in a pavement due to soil liquefaction. Four 1-g shaking table tests were performed on saturated sand bed-pavement... 相似文献
363.
Perveiz Khalid Muhammad Irfan Ehsan Sohail Akram Zia Ud Din Shahid Ghazi 《Journal of the Geological Society of India》2018,92(4):465-470
The reservoir character of the Cretaceous sand is evaluated in Lower Indus Basin, Pakistan where water flooding is very common. Thus, prediction of subsurface structure, lithology and reservoir characterization is fundamental for a successful oil or gas discovery. Seismic reflective response is an important tool to detect sub-surface structure. Seismic reflection response is not enough to highlight geological boundaries and fluids in the pore space therefore, the use of integrated approach is vital to map sub-surface heterogeneities with high level of confidence. Based on seismic character and continuity of prominent reflectors four seismic horizons are marked on the seismic sections. All the strata is highly disturbed and distorted with presence of a network of fault bounded horst and graben structures, which indicate that the area was under compressional tectonic regime. These fault bounded geological structure formed structural traps favorable for the accumulation of hydrocarbon. The petrophysical analysis reveals that the Cretaceous sand formation has four types of sand: Sand A, B, C and D with good porosity (15 % average) and low volume of shale. Although complete petroleum system is present with structural traps and reservoir character of sand interval is very good but these sands are highly saturated with water thus are water flooded, which is the main reason of the abundant wells in the study area. 相似文献
364.
Bushra Khalid Débora Souza Alvim Shumaila Javeed Junaid Aziz Khan Muhammad Asif Javed Azmat Hayat Khan 《Natural Hazards》2018,92(2):971-993
Pakistan has experienced severe floods over the past decades due to climate variability. Among all the floods, the flood of 2010 was the worst in history. This study focuses on the assessment of (1) riverine flooding in the district Jhang (where Jhelum and Chenab rivers join, and the district was severely flood affected) and (2) south Asiatic summer monsoon rainfall patterns and anomalies considering the case of 2010 flood in Pakistan. The land use/cover change has been analyzed by using Landsat TM 30 m resolution satellite imageries for supervised classification, and three instances have been compared, i.e., pre-flooding, flooding, and post-flooding. The water flow accumulation, drainage density and pattern, and river catchment areas have been calculated by using Shutter Radar Topography Mission digital elevation model 90 m resolution. The standard deviation of south Asiatic summer monsoon rainfall patterns, anomalies and normal (1979–2008) has been calculated for July, August, and September by using rainfall data set of Era interim (0.75° × 0.75° resolution). El Niño Southern Oscillation has also been considered for its role in prevailing rainfall anomalies during the year 2010 over Upper Indus Basin region. Results show the considerable changing of land cover during the three instances in the Jhang district and water content in the rivers. Abnormal rainfall patterns over Upper Indus Basin region prevailed during summer monsoon months in the year 2010 and 2011. The El Niño (2009–2010) and its rapid phase transition to La Niña (2011–2012) may be the cause of severity and disturbances in rainfall patterns during the year 2010. The Geographical Information System techniques and model based simulated climate data sets have been used in this study which can be helpful in developing a monitoring tool for flood management. 相似文献
365.
Akber Md. Ali Patwary Muhammad Mainuddin Islam Md. Atikul Rahman Mohammad Rezaur 《Natural Hazards》2018,94(1):405-418
Natural Hazards - Storm protection service of mangrove is often undervalued. This paper empirically assessed the damage avoided by the Sundarbans mangrove forest in 15 villages of southwest coastal... 相似文献
366.
Nowrad Ali Ali Osman Yücel Muhammad Hanif Syed Irfanullah Hashmi Farhat Ullah 《Geodinamica Acta》2018,30(1):31-62
The Pirkoh and Drazinda formations in the Sulaiman Range, central Pakistan, yielded assemblages of (early) Bartonian orthophragminids, characterized predominantly by discocyclinids with a significant number of species probably endemic to Indian Subcontinent. The rarity of Asterocyclina and the absence of Orbitoclypeus and Nemkovella are noteworthy. Ten species of Discocyclina Gümbel and two species of Asterocyclina Gümbel, referable to the Shallow Benthics Zone (SBZ) 17 are described for the first time from Pakistan. The discocyclinids, i.e. Discocyclina praeomphalus, D. sulaimanensis, D. kutchensis, along with the new taxa established here, D. zindapirensis sp. nov., D. rakhinalaensis sp. nov., and D. pseudodispansa sp. nov., seem to be confined to the Indo-Pakistani region (Eastern Tethys). The Discocyclina dispansa, D. discus, D. nandori, and D. augustae lineages known from Western Tethys are also common in the Indian Subcontinent, as are asterocyclinids, such as Asterocyclina sireli and A. stellata. The upper part of the Drazinda Formation (‘Pellatispira beds’), referable to latest Bartonian and/or the early Priabonian, is poor in orthophragminids and is characterized by the occurrence of reticulate Nummulites, Heterostegina, Pellatispira and Silvestriella. The records of ‘Lepidocyclina of Caribbean affinity’ with large embryons from the Eocene of the Indian Subcontinent correspond to misidentified Discocyclina discus. 相似文献
367.
Nasar Khan Naveed Anjum Mansoor Ahmad Muhammad Awais Naqib Ullah 《Journal of Earth System Science》2018,127(7):98
Organic geochemical and palynofacies analyses were carried out on shale intervals of the Late Paleocene Patala Formation at Nammal Gorge Section, western Salt Range, Pakistan. The total organic carbon content and Rock-Eval pyrolysis results indicated that the formation is dominated by type II and type III kerogens. Rock-Eval \({T}_{\mathrm{max}}\) vs. hydrogen index (HI) and thermal alteration index indicated that the analysed shale intervals present in the formation are thermally mature. \(S_{1}\) and \(S_{2}\) yields showed poor source rock potential for the formation. Three palynofacies assemblages including palynofacies-1, palynofacies-2 and palynofacies-3 were identified, which are prone to dry gas, wet gas and oil generation, respectively. The palynofacies assessment revealed the presence of oil/gas and gas prone type II and type III kerogens in the formation and their deposition on proximal shelf with suboxic to anoxic conditions. The kerogen macerals are dominated by vitrinite and amorphinite with minor inertinite and liptinite. The kerogen macerals are of both marine and terrestrial origin, deposited on a shallow shelf. Overall, the dark black carbonaceous shales present within the formation act as a source rock for hydrocarbons with poor-to-moderate source rock quality, while the grey shales act as a poor source rock for hydrocarbon generation. 相似文献
368.
Asam Farid Perviez Khalid Klian Zaib Jadoon Muhammad Asim Iqbal Muhammad Shafique 《山地科学学报》2017,14(1):158-174
This paper studies electrical resistivity dataset acquired for a groundwater study in the Domail Plain in the northwestern Himalayan section of Pakistan. Through a combination of geostatistical analysis, geophysical inversion and visualization techniques, it is possible to re-model and visualize the single dimension resistivity data into 2D and 3D space. The variogram models are utilized to extend the interpretation of the data and to distinguish individual lithologic units and the occurrence of saline water within the subsurface. The resistivity data has been calibrated with the lithological logs taken from the available boreholes. As such the alluvial system of the Domail Plain has formed during episodes of local tectonic activity with fluvial erosion and deposition yielding coarse sediments with high electrical resistivities near to the mountain ranges and finer sediments with medium to low electrical resistivities which tend to settle in the basin center. Thus a change is depositional setting happened from basin lacustrine environment to flash flooding during the Himalayan orogeny. The occurrence of rock salt in the northern mountains has imparted a great influence on the groundwater quality of the study area. The salt is dissolved by water which infiltrates into the subsurface through the water channels. Variogram aided gridding of resistivity data helps to identify the occurrence and distribution of saline water in the subsurface. 相似文献
369.
Natural Hazards - With increasing environmental pressure and the promotion of structural reforms on the supply side, a trend of transformation and upgrading is inevitable in coal-fired power... 相似文献
370.
Natural Hazards - Agriculture involves multiple risks of which environmental and production threats are major ones. Farmers’ risk attitudes and risk perceptions have a significant role in... 相似文献