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131.
Interpretation of landslide distribution triggered by the 2005 Northern Pakistan earthquake using SPOT 5 imagery 总被引:7,自引:4,他引:7
Hiroshi P. Sato Hiroyuki Hasegawa Satoshi Fujiwara Mikio Tobita Mamoru Koarai Hiroshi Une Junko Iwahashi 《Landslides》2007,4(2):113-122
The 2005 northern Pakistan earthquake (magnitude 7.6) of 8 October 2005 occurred in the northwestern part of the Himalayas.
We interpreted landslides triggered by the earthquake using black-and-white 2.5-m-resolution System Pour l’Observation de la Terre 5 (SPOT 5) stereo images. As a result, the counts of 2,424 landslides were identified in the study area of 55 by 51 km. About
79% or 1,925 of the landslides were small (less than 0.5 ha in area), whereas 207 of the landslides (about 9%) were large
(1 ha and more in area). Judging from our field survey, most of the small landslides are shallow rock falls and slides. However,
the resolution and whitish image in the photos prevented interpreting the movement type and geomorphologic features of the
landslide sites in detail. It is known that this earthquake took place along preexisting active reverse faults. The landslide
distribution was mapped and superimposed on the crustal deformation detected by the environmental satellite/synthetic aperture
radar (SAR) data, active faults map, geological map, and shuttle radar topography mission data. The landslide distribution
showed the following characteristics: (1) Most of the landslides occurred on the hanging-wall side of the Balakot–Garhi fault;
(2) greater than one third of the landslides occurred within 1 km from the active fault; (3) the greatest number of landslides
(1,147 counts), landslide density (3.2 counts/km2), and landslide area ratio (2.3 ha/km2) was found within Miocene sandstone and siltstone, Precambrian schist and quartzite, and Eocene and Paleocene limestone and
shale, respectively; (4) there was a slight trend that large landslides occurred on vertically convex slopes rather than on
concave slopes; furthermore, large landslides occurred on steeper (30° and more) slopes than on gentler slopes; (5) many large
landslides occurred on slopes facing S and SW directions, which is consistent with SAR-detected horizontal dominant direction
of crustal deformation on the hanging wall. 相似文献
132.
Wan Yongge 《中国地震研究》2007,21(1):33-42
The influences upon aftershocks of Coulomb failure stress change (CFSC) generated by the main-shock of the October 8, 2005, Pakistan earthquake are calculated and analyzed. The following factors are included in the calculation: (1) the difference between the pore fluid pressure and the medium elastic constant in the fault plane area and those of its surrounding medium; (2) the tectonic stress direction of the seismic source area; (3) the aftershock failure mechanism of aftershocks is calculated by stacking the tectonic stress with the stress change generated by the main-shock. Our study, which includes many factors, fits fairly well with the aftershock distribution. It indicates that most of the aftershocks were triggered by the Pakistan main-shock that occurred on October 8, 2005. 相似文献
133.
Mary Louise Pratt uses the term autoethnography to refer to those instances in which members of colonized groups strive to represent themselves to their colonizers in ways that engage with colonizers' terms while also remaining faithful to their own self‐understandings. This paper extends Pratt's conceptualization of autoethnography and describes how it may be used to inform field research in transcultural settings in the formerly colonized world. Drawing from research in a village in northern Pakistan, we argue that approaching fieldwork with an “autoethnographic sensibility” can yield important epistemological, methodological, and political insights into our research practices. The paper concludes by suggesting that these insights extend beyond a postcolonial, or even cross‐cultural, research context, to inform more general debates in human geography about how to achieve a critical and reflexive research practice. 相似文献
134.
Tahir Rafique Shahid Naseem Muhammad I. Bhanger Tanzil H. Usmani 《Environmental Geology》2008,56(2):317-326
Groundwater samples were collected from various localities of Mithi sub-district of the Thar Desert of Pakistan and analysed
for fluoride ion along with other chemical parameters. The area is mainly covered by sand dunes and kaolin/granite at variable
depths. Results showed that collected water samples were severely contaminated by the presence of fluoride ion and most of
the samples have higher concentration than prescribed WHO standards (1.5 mg/l) for drinking water. Fluoride ion concentrations
ranged between 0.09 and 11.63 mg/l with mean and median values of 3.64 and 3.44 mg/l, respectively, in this area whereas,
distribution pattern showed high concentrations in the vicinity of Islamkot and Mithi towns. The content of F− has also been correlated with other major ions found in the groundwater of the study area. The positive correlation of F− with Na+ and HCO3
− showed that the water with high Na+ and HCO3
− stabilizes F− ions in the groundwater of the Thar Desert. The pH versus F− plots signifies high fluoride concentration at higher pH values, implying that alkaline environment favours the replacement
of exchangeable OH− with F− in the groundwater of Mithi area. The saturation indices (SI) of fluorite (CaF2) and calcite (CaCO3) in the groundwater samples showed that most of the samples are oversaturated with respect to calcite whereas majority of
samples have been found under saturated with respect to fluorite. The log TDS and Na/Na+Ca ratio reflected supremacy of weathering
of rocks, which promotes the availability of fluoride ions in the groundwater. Piper diagram has been used to classify the
hydrofacies. In the cation triangle, all samples are Na-type, while the anion triangle reflects major dominance of Cl-type
with a minor influence of HCO3
− and SO4
−. 相似文献
135.
Z. Sagintayev M. Sultan S. D. Khan S. A. Khan K. Mahmood E. Yan A. Milewski P. Marsala 《水文研究》2012,26(1):85-99
The lack of adequate field measurements often hampers the construction and calibration of rainfall‐runoff models over many of the world's watersheds. We adopted methodologies that rely heavily on readily available remote sensing datasets as viable alternatives for assessing, managing, and modelling of such remote and inadequately gauged regions. The Soil and Water Assessment Tool was selected for continuous (1998–2005) rainfall‐runoff modelling of one such area, the northeast part of the Pishin Lora basin (NEPL). Input to the model included satellite‐based Tropical Rainfall Measuring Mission precipitation data, and modelled runoff was calibrated against satellite‐based observations, the latter included: (i) monthly estimates of the water volumes impounded by the Khushdil Khan (latitude 30°40′N, longitude 67°40′E), and the Kara Lora (latitude 30°34′N, longitude 66°52′E) reservoirs, and (ii) inferred wet versus dry conditions in streams across the NEPL. Calibrations were also conducted against observed flow reported from the Burj Aziz Khan station at the NEPL outlet (latitude 30°20′N; longitude 66°35′E). Model simulations indicate that (i) average annual precipitation (1998–2005), runoff and recharge in the NEPL are 1300 × 106 m3, 148 × 106 m3, and 361 × 106 m3, respectively; (ii) within the NEPL watershed, precipitation and runoff are high for the northeast (precipitation: 194 mm/year; runoff: 38 × 106 m3/year) and northwest (134 mm/year; 26 × 106 m3/year) basins compared to the southern basin (124 mm/year; 8 × 106 m3/year); and (3) construction of delay action dams in the northeast and northwest basins could increase recharge from 361 × 106 m3/year up to 432 × 106 m3/year and achieve sustainable extraction. The adopted methodologies are not a substitute for traditional approaches, but they could provide first‐order estimates for rainfall, runoff, and recharge in the arid and semi‐arid parts of the world that are inaccessible and/or lack adequate coverage with field data. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
136.
通过宝石显微镜、显微红外、电子探针和拉曼光谱等测试方法对巴基斯坦祖母绿的孔道水和包裹体进行了研究。红外光谱测试可知,巴基斯坦祖母绿中存在Ⅰ型和Ⅱ型水,且Ⅱ型水(5 270、3 600、1 632 cm~(-1))吸收强度远大于Ⅰ型水(1 600 cm~(-1))。流体包裹体以气液两相包裹体为主,常呈拉长状或"卡脖子"状形态,且定向排列,气相包裹体主要成分为CO_2+N_2+CH_4的混合气体,液相主要为水溶液;矿物包裹体主要有菱镁矿、白云石、白云母、石英等。特征包裹体和红外光谱特征有助于鉴定巴基斯坦祖母绿的产地来源。 相似文献
137.
《Geoforum》2017
Environmental security concerns have broadened the national security agenda and discourse of international relations. Yet environmental insecurity issues have endured impacts on livelihood, human security, social equity, human rights, internal security, political stability, economic growth and development of the state. Environmental challenges, such as climate change, water scarcity and energy security are shaping development and consumption patterns, which are possible causes of inter-state conflict in South Asia. This paper is an attempt to evaluate the nexus of climate change, energy and water security with conflict and development. Furthermore, we argue for the need for environmental diplomacy in Pakistan within the South Asian context. The argument is that integration of development with environmental factors and peacemaking has potential to achieve sustainable development in South Asia. 相似文献
138.
Alam UZ 《The Geographical journal》2002,168(4):341-353
The water wars rationale predicts that countries will wage war to safeguard their access to water resources, especially if there is water scarcity, competitive use and the countries are enemies due to a wider conflict. Following this argument, India and Pakistan should have fought a war over the Indus basin instead of negotiating the 1960 Indus Waters Treaty. In explaining this Indo–Pakistan cooperation which is specifically over water, the critical feature that emerges is that through cooperation the countries were able to safeguard their long–term water supply. In other words, cooperation is water rational. Using the Indus basin experience, the underlying logic of the water wars rationale is questioned, in particular, the use of public statements by key decisionmakers as evidence of future water wars and is shown to be wanting. 相似文献
139.
The distribution of Zn, Pb, Cu, Cr, Ni and Co in the plant species and soil of the Zn-Pb sulfide deposits of the Besham area in Pakistan has been studied for geochemical prospecting and environmental pollution. Representative samples of several plant species and associated soil were collected and analyzed by the atomic absorption technique. The data suggest that the plants, especially Plectranthus rugosus, Artemisia indica and Verbascum thapsus, in the mineralized area are enriched in Zn, Pb and Cu (Zn>Pb>Cu) and depleted in Cr, Ni and Co. This is correlated with the concentration of these metals in the associated soil. There is no significant correlation of elements among each other in plants and soil; however, strong correlation of Cu, Cr and Ni has been observed between plants and associate soil. Plectranthus rugosus has the greatest capability for accumulating Zn and Pb in its tissues through soil and can be used as a bioindicator for base metal mineral exploration. This plant along with other plant species such as Artemisia indica and Verbascum thapsus having high scavenging ability for Zn and Pb from the soil and could cause serious environmental and health problems in the living organisms of the area. 相似文献
140.
The southern Makran fold-thrust belt, Pakistan, displays unique outcrop examples of well-exposed, kilometre-scale, listric growth faults that displace Miocene-age deltaic growth strata by several hundreds of metres to kilometers. The largest growth faults are counter-regional (landward-dipping), bounding major clastic depocentres exposed over areas > 1000 km2. Stratal offset along these faults can exceed 1.5 km. Fault-zone thicknesses range between ca. 100 and 400 m, and average fault thickness-displacement ratios are around 1:10. High-resolution satellite data show in unprecedented detail the faults and the stratigraphic architecture of associated growth sequences, which comprise kilometre-scale progradational clinoforms, thick mudstone units and basinwards wedging sandstone-shale deposits. The true vertical thickness of the syn-kinematic record is, in places, up to 8 km, making the outcrop examples equivalent to major growth faulted successions known from seismic data of large deltas, and at least an order of magnitude larger than other outcrop examples. A comparison of the Makran outcrops with seismic-reflection examples offshore NW Borneo reveals distinct similarities in the gross depocentre geometries and internal architecture. The key control for growth faulting is interpreted to result from sedimentary loading, with rapid sedimentary progradation causing the development of rollover synclines by differential compaction and fluid expulsion, and counter-regional growth faults preferentially forming on the basinward side of these synclines. The data and interpretations presented can be used to assess the key parameters that contribute to the development of growth faults and growth successions above shale, reinforcing structural and stratigraphic observations from seismic interpretation and modelling studies in demonstrating their occurrence in exposure. 相似文献