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61.
Stochastic Environmental Research and Risk Assessment - During the span of August–October, 2017 a major outbreak of Dengue fever happened in Khyber Pakhtunkhwa province of Pakistan. Cases...  相似文献   
62.
Land degradation reduces the ability of the land to perform many biophysical and chemical functions. The main aim of this study was to determine the status of land degradation in the Budgam area of Kashmir Himalaya using remote sensing and geographic information system. The satellite data together with other geospatial datasets were used to quantify different categories of land degradation. The results were validated in the field and an accuracy of 85% was observed. Land use/land cover of the study area was determined in order to know the effect of land use on the rate of land degradation. Normalized differential vegetation index (NDVI) and slope of the area were determined using LANDSAT-enhanced thematic mapper plus (ETM+) data, advanced space borne thermal emission and reflection radiometer, and digital elevation model along with other secondary data were analysed to create various thematic maps, viz., land use/land cover, geology, NDVI and slopes used in modelling land degradation in the Kashmir Himalayan region. The vegetation condition, elevation and land use/land cover information of the area were integrated to assess the land degradation scenario in the area using the ArcGIS ‘Spatial Analyst Module’. The results reveal that about 13.19% of the study area has undergone moderate to high degradation, whereas about 44.12% of the area has undergone slight degradation.  相似文献   
63.
Raza  Maimoona  Lee  Jin-Yong 《Water Resources》2022,49(3):515-524
Water Resources - In the Republic of Korea, Haean basin is the largest agricultural area in Soyang watershed which is drinking water source for more than 20 million people residing in Seoul...  相似文献   
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Analysis of the anomalous magnetic mineral intensities and geochemistry for placer gold deposits are presented for those of the Attock area at the confluence of the Indus and Kabul rivers in northwestern Pakistan. Two grids covering an area of 10 x18 m2 and 8 x10 m2 were analyzed using a G-858 Cesium Vapor Magnetometer. The anomalous zones obtained were plotted on contour maps, 2 D and 3 D magnetic intensity maps. Based on the magnetic anomalies, grid-1 of the study area wa...  相似文献   
66.
The Luconia Province—offshore Sarawak—is a key hydrocarbon province in Malaysia. However, the gas reservoirs in Central Luconia pose unique problems and challenges as they have partially water-filled microporosity that overprint wireline logs. Microporosity in Central Luconia occurs throughout the Miocene carbonates and is a crucial element that influences fluid flow properties and ultimately the recovery of hydrocarbons. Quantification of macroporosity was achieved using petrographic analysis of thin sections and the FESEM images. The point counting technique was used to estimate the amount of macroporosity from the thin section, which was then subtracted from the total porosity to derive microporosity. The qualitative investigation of the Miocene carbonates indicates the presence of three different types of microporosity namely grain-based microporosity, matrix-based microporosity, and cement-based microporosity. Quantification of microporosity showed that the microporosity varies from sample to sample, ranging from 10 to 60% of the total measured porosity. The depositional texture, mineralogy, and microtexture control this microporosity variation including its abundance and type. The microporosity in Central Luconia is diagenetically controlled based on four major diagenetic mechanisms namely (1) mechanical process/endolithic grains/marine diagenesis; (2) leaching/meteoric diagenesis; (3) cementation/shallow diagenesis; and (4) deeper diagenesis environment.  相似文献   
67.
This paper presents results of a pilot study in six villages located in the states of Haryana, Rajasthan and Madhya Pradesh, to evaluate accuracy of crop area at village level estimated by IRS - LISS-I1I data with respect to detailed field survey carried out by National Sample Survey Organization. The selected villages were located in Karnal, Kota and Bhopal districts which represented single dominant wheat crop as well as wheat-mustard and wheat-gram situation, respectively. Accuracy assessment of remote sensing based estimate with field survey of NSSO showed relative deviation in wheat estimate ranging from 3.72 percent for Mainmati village in Karnal district in Haryana to 22.65 percent fo Ranpur village in Kota district of Rajasthan. It was found that relative deviation in area estimation is inversely poportional to the crop proportion in that village. Observations of over estimation at low crop proportion and underestimation at higher crop proportion was explained by simple budgeting of relative proportion of ommision and commision errors. The study demonstrates that on the average, 90 percent crop area accuracy is possible with LISS-II1 data and the adopted approach.  相似文献   
68.
Journal of Earth System Science - The artificial recharge is a technique of aquifer conservation for land subsidence. But in this article, the phenomenon of land subsidence and the resulting cracks...  相似文献   
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70.
Fission track thermotectonic imaging of the Australian continent   总被引:1,自引:0,他引:1  
Fission track analyses of apatites from a very large data set across Australia provide a first look at the patterns of low-temperature thermochronology over an entire continent. The rock samples are mostly of granitic rocks, or their metamorphic equivalents, of Palaeozoic or older age from the exposed basement regions. Sample chemical analyses indicate that the apatite suite is overwhelmingly of fluorapatite composition. Approximately 2750 fission track analyses have been completed, of which >1700 are of sufficient quality to form a coherent data set that can be interpolated to show the variation of central fission track age and mean confined track length on a continental scale. The resulting images exhibit some features which are well known, such as the trend towards young apatite ages along the eastern and southeastern rifted continental margins, but others that are more surprising, such as the lack of clear differentiation, in terms of the range of ages and lengths, between the older Precambrian cratonic areas in the west, and younger Phanerozoic mobile belts to the east. The Precambrian rocks from the western two-thirds of the continent do, however, show distinctly different cooling histories to those in the eastern Phanerozoic mobile belts when the relationships between track lengths and fission track ages are considered. The western craton everywhere shows patterns of prolonged slow cooling, whereas all major regions of the eastern part of the continent show discrete episodes of rapid cooling, mostly from the Jurassic to the Palaeogene. Significant areas of unusually young apatite ages (<50 Ma) are found in Tasmania and in Precambrian rocks from the northern Gawler Block in South Australia. The most obvious regional cause of the overall fission track patterns across Australia is variation in surface denudation over time scales of hundreds of Ma. However, in some areas, such as the northern Gawler Block, other mechanisms such as the movement of hydrothermal fluids in former cover sequences must be invoked.  相似文献   
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