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Decadal trends in precipitable water vapor over the Indus River Basin using ERA5 reanalysis data 被引量:1
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作者 Seema RANI Jyotsna SINGH +2 位作者 Subhash SINGH Purushottam TIWARI Suraj MAL 《Journal of Mountain Science》 SCIE CSCD 2023年第10期2928-2945,共18页
Precipitable Water Vapor(PWV)constitutes a pivotal parameter within the domains of atmospheric science,and remote sensing due to its profound influence on Earth’s climate dynamics and weather patterns.It exerts a sig... Precipitable Water Vapor(PWV)constitutes a pivotal parameter within the domains of atmospheric science,and remote sensing due to its profound influence on Earth’s climate dynamics and weather patterns.It exerts a significant impact on atmospheric stability absorption and emission of radiation,thus engendering alterations in the Earth’s radiative equilibrium.As such,precise quantification of PWV holds the potential to enhance weather prognostication and fortify preparedness against severe meteorological phenomena.This study aimed to elucidate the spatial and temporal changes in seasonal and annual PWV across the Indus River Basin and its sub-basins using ERA5 reanalysis datasets.The present study used ERA5 PWV(entire atmospheric column),air temperature at 2 m(t2m)and 500 hPa(T_500hPa),evapotranspiration,and total cloud cover data from 1960 to 2021.Theil Sen slope estimator and Mann-Kendall test were used for trend analysis.Correlation and multiple regression methods were used to understand the association of PWV with other factors.The findings have unveiled the highest increase in mean PWV during the monsoon(0.40 mm/decade),followed by premonsoon(0.37 mm/decade),post-monsoon(0.27 mm/decade),and winter(0.19 mm/decade)throughout the study period.Additionally,the mean PWV exhibited the most pronounced positive trend in the sub-basin Lower Indus(LI),followed by Panjnad(P),Kabul(K),and Upper Indus(UI)across all seasons,except winter.Annual PWV has also risen in the Indus basin and its sub-basins over the last six decades.PWV exhibits a consistent upward trend up to an elevation of 3500 m within the basin which is most pronounced during the monsoon season,followed by the pre-monsoon.The escalating PWV within the basin is reasonably ascribed to increasing air temperatures,augmented evapotranspiration,and heightened cloud cover.These findings hold potential utility for pertinent authorities engaged in water resource management and planning. 展开更多
关键词 HIMALAYA Precipitable Water Vapor indus River Basin ATMOSPHERE Climate Change ERA5 Reanalysis data
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Genesis of the Gold Deposit in the Indus-Yarlung Tsangpo Suture Zone,Southern Tibet:Evidence from Geological and Geochemical Data 被引量:5
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作者 ZHANG Xiong DENG Xueguo +9 位作者 YANG Zhusen HOU Zengqian ZHENG Yuanchuan LIU Yingchao ZHAO Xiaoyan XU Bo PEI Yingru ZHOU Jinsheng ZHAO Miao YUAN Jianfei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第3期947-970,共24页
The Nianzha gold deposit, located in the central section of the Indus-Yarlung Tsangpo suture (IYS) zone in southern Tibet, is a large gold deposit (Au reserves of 25 tons with average grade of 3.08 g/t) controlled... The Nianzha gold deposit, located in the central section of the Indus-Yarlung Tsangpo suture (IYS) zone in southern Tibet, is a large gold deposit (Au reserves of 25 tons with average grade of 3.08 g/t) controlled by a E-W striking fault that developed during the main stage of Indo-Asian collision (-65-41 Ma). The main orebody is 1760 m long and 5.15 m thick, and occurs in a fracture zone bordered by Cretaceous diorite in the hanging wall to the north and the Renbu tectonic melange in the footwall to the south. High-grade mineralization occurs in a fracture zone between diorite and ultramafic rock in the Renbu tectonic melange. The wall-rock alteration is characterized by silicification in the fracture zone, serpentinization and the formation of talc and magnesite in the uitramafic unit, and chloritization and the formation of epidote and calcite in diorite. Quartz veins associated with Au mineralization can be divided into three stages. Fluid inclusion data indicate that the deposit formed from H20-NaCl-organic gas fluids that homogenize at temperatures of 203℃-347℃ and have salinities of 0.35wt%-17.17wt% NaCI equivalent. The quartz veins yield δ18Ofluid values of 0.15‰-10.45‰, low δDv-SMow values (-173%o to -96%o), and the δ13C values of-17.6‰ to -4.7‰, indicating the ore-forming fluids were a mix of metamorphic and sedimentary orogenic fluids with the addition of some meteoric and mantle-derived fluids. The pyrite within the diorite has δ34SV-CDT values of -2.9‰-1.9‰(average -1.1‰), 206pb/204pb values of 18.47- 18.64, 207pb/204pb values of 15.64-15.74, and 208pb/204pb values of 38.71-39.27, all of which are indicative of the derivation of S and other ore-forming elements from deep in the mantle. The presence of the Nianzha, Bangbu, and Mayum gold deposits within the IYS zone indicates that this area is highly prospective for large orogenic gold deposits. We identified three types of mineralization within the IYS, namely Bangbu-type accretionary, Mayum-type microcontinent, and Nianzha-type ophiolite-associated orogenic Au deposits. The three types formed at different depths in an aeeretionary orogenic tectonic setting. The Bangbu type was formed at the deepest level and the Nianzha type at the shallowest. 展开更多
关键词 GEOLOGY gold mineralization Nianzha Deposit indus-yarlung Tsangpo suture zone TIBET
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Early Triassic Volcanic Rocks in the Western Yarlung Zangbo Suture Zone:Implications for the Opening of the Neo-Tethys Ocean 被引量:1
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作者 HE Juan LI Yalin +4 位作者 HOU Yunling ZHOU Aorigele WEI Yushuai CHEN Xi DAI Jingen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期324-336,共13页
In this study,zircon U-Pb dating of volcanic rocks from the Zhongba ophiolite of the Yarlung Zangbo Suture Zone(YZSZ)in southern Xizang(Tibet)yielded an age of 247±3 Ma.According to whole rock geochemical and Sr-... In this study,zircon U-Pb dating of volcanic rocks from the Zhongba ophiolite of the Yarlung Zangbo Suture Zone(YZSZ)in southern Xizang(Tibet)yielded an age of 247±3 Ma.According to whole rock geochemical and Sr-NdPb isotopic data,the Early Triassic samples could be divided into two groups:Group 1 with P-MORB affinity,showing initial^(87)Sr/^(86)Sr ratios of 0.70253–0.70602,ε_(Nd)(t)values of 4.2–5.3,(^(206)Pb/^(204)Pb)_(t)ratios of 16.353–18.222,(^(207)Pb/^(204)Pb)_(t)ratios of 15.454–15.564,and(^(208)Pb/^(204)Pb)_(t)ratios of 35.665–38.136;Group 2 with OIB affinity,showing initial^(87)Sr/^(86)Sr ratios of 0.70249–0.70513,ε_(Nd)(t)values of 4.4–4.9,(^(206)Pb/^(204)Pb)_(t)ratios of 17.140–18.328,(^(207)Pb/^(204)Pb)_(t)ratios of 15.491–15.575,and(^(208)Pb/^(204)Pb)_(t)ratios of 36.051–38.247.Group 2 rocks formed by partial melting of the mantle source enriched by a former plume,and assimilated continental crustal material during melt ascension.The formation of Group 1 rocks corresponds to the mixing of OIB melts,with the same components as Group 2 and N-MORBs.The Zhongba Early Triassic rocks belong to the continental margin type ophiolite and formed in the continental–oceanic transition zone during the initial opening of the Neo-Tethys in southern Xizang(Tibet). 展开更多
关键词 RIFT Early Triassic magmatism yarlung Zangbo Suture Zone NEO-TETHYS Southern Xizang TIBET
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Comprehensive isotopic characterization of the hydrological processes of the Indus river basin(IRB):A comparison between Upper Indus Basin(UIB)and Lower Indus Basin(LIB)
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作者 Akhtar JAHAN Tanveer DAR +1 位作者 Sudhir KUMAR Nachiketa RAI 《Journal of Mountain Science》 SCIE CSCD 2023年第3期705-723,共19页
The Indus river basin(IRB)is one of the most depleted water basins globally,having significant challenges for its water sector.Monitoring of stable isotope composition(δ^(18)O and δ^(2)H)across IRB is a critical asp... The Indus river basin(IRB)is one of the most depleted water basins globally,having significant challenges for its water sector.Monitoring of stable isotope composition(δ^(18)O and δ^(2)H)across IRB is a critical aspect that can provide deeper insights for investigating complex hydrological processes.This work analyses the spatial pattern of the isotopic signature using a comprehensive compilation of available datasets of the Global Network of Isotopes in River(GNIR)and Global Network of Isotopes in Precipitation(GNIP),along with the previously published isotopic studies in the Indus basin.Additionally,this work provides a detailed comparison of the isotopic signature of the Upper Indus Basin(UIB),and Lower Indus Basin(LIB).The IRBs waterline was found to beδ^(2)H=7.89×δ^(18)O+13.51,which shows a close similarity with the Global Meteoric Water Line(GMWL),indicating the meteoric origin of the water with insignificant secondary evaporation prevailing across the basin.The Main Indus Channel(MIC)river water line(δ^(2)H=8.88×δ^(18)O+26.05)indicates a major contribution from the meteoric origin(precipitation/rain)of water with minimal effect of evaporation processes.The water line for UIB samples,(δ^(2)H=7.88×δ^(18)O+11.94)was found to be moderately higher in slope than LIB samples(δ^(2)H=7.17×δ^(18)O+7.16).However,the slopes of both UIB and LIB river water lines closely approached the slope of GMWL and were consistent with the slope of IRB water line,which indicates similarity in contribution of water sources.The higher slope and intercept in UIB suggest that meteoric water sources contributed to streamflow viz.from snow/glacier with insignificant evapotranspiration,which is also validated by the scarce vegetation cover in the UIB.However,the lower slope and intercept in LIB suggest stream water contribution from significantly evaporated groundwater and precipitation with a complete homogenization of discharge coming from the UIB.Results substantiate that distinct isotopic signatures found in different stretches of the IRB and along the MIC are caused by variations in basin characteristics,hydro-meteorological processes,water mixing,and minor influence of anthropogenic variables. 展开更多
关键词 ISOTOPES Spatial variability Indian summer monsoon Western Disturbance indus river Water
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Evaluating spatial and elevation-wise daytime/nighttime LST trends across the Indus River Basin
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作者 Suraj MAL Kavya AGRAWAL +2 位作者 Seema RANI Pyarimohan MAHARANA Viswanathan Anantha Venkat RAMAN 《Journal of Mountain Science》 SCIE CSCD 2023年第11期3154-3172,共19页
Land surface temperature(LST)is a crucial parameter for understanding the Earth's surface energy balance,which provides insights into climate dynamics and local environmental conditions.Thus,the present study aims... Land surface temperature(LST)is a crucial parameter for understanding the Earth's surface energy balance,which provides insights into climate dynamics and local environmental conditions.Thus,the present study aims to evaluate the spatial and elevation-wise trends in the daytime,nighttime,and mean LST across the Indus River Basin(IRB)using MODIS 8-day product for the period between 2002 and 2022.The elevation,cloud cover,and land cover type data are used for explaining the emerging LST trends.The Theil slope estimator and MannKendall significance test were used for estimating the seasonal and annual LST trends.The findings show warming in mean daytime(0.020-0.024℃/yr)(except winter and post-monsoon),nighttime(0.013-0.049℃/yr),and mean(0.001-0.042℃/yr)LST in all the seasons(highest in monsoon).The annual mean nighttime LST(0.025℃/yr)is rising significantly faster than the mean daytime LST(0.0016℃/yr),showing the presence of a“nighttime warming effect”,which possibly increases human discomfort,particularly during the warm pre-monsoon and humid monsoon season.Elevation-dependent warming(EDW)is predominant in mean daytime LST in two elevation zones,namely(i)0-3 km and(ii)above 4 km,in all seasons,except in post-monsoon.In contrast,EDW in mean nighttime LST is observed up to 3 km and above 6 km in the basin in all the seasons,excluding post-monsoon.The warming trend in LST may be attributed to rising atmospheric moisture,cloud cover,declining snow cover,and changes in land cover to non-vegetated land.However,further investigations will involve exploring the underlying factors contributing to the observed anomalies in nighttime LST,considering variables such as regional energy balance and atmospheric stability.This research contributes to an understanding of the thermal dynamics in the mountain basin,aiding in climate studies,land management,and the development of effective adaptation strategies in the IRB. 展开更多
关键词 Land surface temperature Elevation dependent warming indus river basin South Asia
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Assessment of the spatial extent of permafrost in the Upper Indus Basin(UIB)
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作者 Wasim HASSAN G.JEELANI +1 位作者 A.P.DIMRI Marcus NüSSER 《Journal of Mountain Science》 SCIE CSCD 2023年第6期1508-1525,共18页
Climate change differentially influences the frozen ground,a major dynamic component of the cryosphere,on a local and regional scale.Under the warming climate with pronounced effects reported at higher altitudes,the c... Climate change differentially influences the frozen ground,a major dynamic component of the cryosphere,on a local and regional scale.Under the warming climate with pronounced effects reported at higher altitudes,the characterization of the frozen ground is very important in the Upper Indus Basin(UIB),an important and critical region with respect to climate and hydro-glaciological dynamics.In this study,the efficiency and reliability of the surface frost number model are assessed in delineating the spatial extent of different classes of frozen ground in the region.The daily MODIS land surface temperature(LST)with ground surface temperature(GST)and surface geomorphological expressions as ground validation datasets are used jointly in efficiently determining the extent of different classes of frozen ground(continuous and discontinuous permafrost and seasonal frost).The LST and GST resonate with each other in the annual cycle of temperature variation,however,with mean annual LST exhibiting an offset(cold bias)of 5 to 7℃relative to mean GST.This study shows that the highest permafrost extent is observed in areas where the lowest thinning rates of glacier ice are reported and vice versa.The surface frost number model categorizes an area of 38%±3%and 15%±3%in the UIB as permafrost and seasonal frost,respectively.Based on the altitude model,the lower limit of alpine permafrost is approximated at a mean altitude of 4919±590 m a.s.l.in the UIB.The present study acts as preliminary work in the data sparse and inaccessible regions of the UIB in characterizing the frozen and unfrozen ground and may act as a promising input data source in glaciohydro-meteorological models for the Himalaya and Karakoram.In addition,the study also underlines the consideration of this derelict cryospheric climatic variable in defining and accounting for the sustainable development of socio-economic systems through its intricate ramification on agricultural activity,landscape stability and infrastructure. 展开更多
关键词 Upper indus Basin Land surface temperature Ground surface temperature Surface frost number PERMAFROST Seasonal frost
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A Glance on the Mineral Deposits and Stratigraphic Sequential Variations and Structures in Different Sections of Indus Basin (Pakistan): New Titanosaurian Sauropod Dinosaurs from the Latest Maastrichtian Vitakri Formation of Pakistan
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作者 Muhammad Sadiq Malkani 《Open Journal of Geology》 2023年第10期1069-1138,共70页
Indus basin hosts many significant mineral deposits like gypsum and cement raw materials, gemstones, iron, coal, marble, dimension and construction stones, petroleum and water resources, world class pink salt and othe... Indus basin hosts many significant mineral deposits like gypsum and cement raw materials, gemstones, iron, coal, marble, dimension and construction stones, petroleum and water resources, world class pink salt and other many minerals in different regions which need further exploitation and development. The construction of new water dams in different regions are vital (for availability of cheap electricity), because of available barren and fertile lands and wastage of water as flood. Further the installation of more cement industries in different regions of Indus Basin especially in middle Indus (Sulaiman Range where gypsum, clays and limestones can be available via belt) can increase export to receive more foreign exchange and make local cement cheap for the sustainable development of Pakistan. 31 stratigraphic sequential sections at different sections of Indus basins are presented to know the variation and local stratigraphy. Further here three new titanosaur taxa are being described. Saraikimasoom is based on snout;Gspsaurus, (Maojandino), Nicksaurus and Khanazeem are based on cranial, vertebral and appendicular elements;Balochisaurus, Marisaurus, Pakisaurus, and 3 new genera and species Imrankhanhero zilefatmi, Qaikshaheen masoomniazi and Ikqaumishan smqureshi based on vertebral and appendicular elements;and Sulaimanisaurus and Khetranisaurus based on only caudal vertebrae. Although Pakistani Titanosaurians seem to be proliferated found from one horizon of Vitakri Formation just below the K-Pg boundary they have a wide range of diagnostic features and key elements among titanosaurs which can be used for comparison and phylogenetic analyses with broad updated character data set of titanosaurs. 展开更多
关键词 Mineral Deposits Stratigraphic Sequences STRUCTURES Multiple Sections indus Super Basin New Titanosaurs Latest Maastrichtian Vitakri Formation Pakistan
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Mineralogy and element geochemistry of the Sohnari rocks of Early Eocene Laki Formation in the Southern Indus Basin,Pakistan:Implications for paleoclimate,paleoweathering and paleoredox conditions
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作者 Asghar A.A.D.Hakro Sajjad Ali +5 位作者 Abdul Shakoor Mastoi Riaz Hussain Rajper Rizwan Sarwar Awan Muhammad Soomar Samtio Hong Xiao Xiaolin Lu 《Energy Geoscience》 2023年第1期143-157,共15页
The Sohnari Member of the Early Eocene Laki Formation is massively deposited in the Southern Indus Basin of Pakistan and is considered a potential source rock to generate hydrocarbons.However,the detailed paleoclimati... The Sohnari Member of the Early Eocene Laki Formation is massively deposited in the Southern Indus Basin of Pakistan and is considered a potential source rock to generate hydrocarbons.However,the detailed paleoclimatic,paleoweathering,and depositional conditions of the Sohnari Member have not been studied earlier.This research mainly discusses the detailed mineralogical(bulk and clay)and elemental geochemistry of the Laki Formation from two outcrop sections(Jhimpir and Lakhra)in the Southern Indus Basin,Pakistan.The bulk minerals,including quartz(low),hematite,calcite,halite,gypsum,and clay minerals such as kaolinite,chlorite,smectite and illite have been discussed here.These results demonstrate the paleo-environment of studied area was arid with enhanced saline and weak to strong oxidizing depositional conditions.The chemical index of alteration(CIA)values in Jhimpir and Lakhra sections are in the ranges of 41.30-97.93 and 22.30-96.19,respectively,indicating that the Sohnari sediments experienced weak to intense chemical weathering in the source area.The interpretation of the A-CN-K ternary diagram is consistent with the clay mineral contents in the studied sediments,which is characterized by the predominance of kaolinite,gibbsite and chlorite,demonstrating the weak to strong weathering state under warm and humid climatic conditions.The chemical indices such as Sr/Ba,δU,V/Cr,Ni/Co,and Cu/Zn,U/Th and Ba/Ga show that Sohnari rocks of Early Eocene Laki Formation underwent strong evaporation,oxic water column with warm to humid and minor contact of cold climatic conditions.Based on our present data,it can be concluded that the sediments of Sohnari Member of Laki Formation from Jhimpir and Lakhra areas of Southern Indus Basin in Pakistan are related to Indio-Eurasian collision and came from the Indian shield rocks that were deposited in a brackish water body with a minor contact of the freshwater oxidizing paleo-environment depositional conditions. 展开更多
关键词 MINERALOGY Geochemistry PALEOCLIMATE Sohnari Southern indus basin Lakhra
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Evaluation of soil loss severity and ecological restoration approach for sustainable agriculture in the Hindu Kush, Karakoram and Himalaya region
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作者 Arshad ASHRAF Imran AHMAD 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1509-1521,共13页
Soil erosion has resulted in removal of the topsoils containing fine soil particles and plant nutrients, causing decrease in soil fertility in the Hindu Kush, Karakoram and Himalaya(HKH) region. The existing productio... Soil erosion has resulted in removal of the topsoils containing fine soil particles and plant nutrients, causing decrease in soil fertility in the Hindu Kush, Karakoram and Himalaya(HKH) region. The existing production of cereal crop grains has been reduced to one third of the potential crop grains production owing to land degradation and poor farming practices. It is necessary to assess risk of soil loss and identify appropriate controlling measures to address issues of low agriculture productivity and water insecurity in the region. In the present study, severity of soil loss was predicted using Revised Universal Loss Equation(RUSLE) and ecological measures were identified for sustainable mountain agriculture in the HKH region of Upper Indus Basin, Pakistan. Overall 62.6% area was found to have very low risk of soil loss, i.e., <5 t/(ha·yr), 15.8% area low risk, i.e., 5-25 t/(ha·yr) and 7.5% area moderate risk, i.e., 25-50 t/(ha·yr) in the region. The risk was high, i.e., 50-100 t/(ha·yr) and very high, i.e., >100 t/(ha·yr) in about 6.8% and 7.4% areas respectively. The mean rate of soil loss was about 41.9 t/(ha·yr) in the Hindu Kush, 31.1 t/(ha·yr) in the Himalayas, 18.8 t/(ha·yr) in the Karakoram and overall 29.7 t/(ha·yr) in the three HKH ranges. As such no considerable measures have been adopted by the communities for restoration of the degraded areas except raising fruit/farm trees and supporting limited social forestry for their livelihoods. The slopes cleared for cultivation and susceptible to erosion may be stabilized through sowing/planting of multi-purpose plant species and formation of proper bench terraces. The conservation of forest ecosystem and pastures at higher elevations would help in reducing overland water flow, risk of flash flood hazard and minimizing sediment loads in the downstream. It is essential to adopt site-specific resource conservation techniques and restore possible ecosystem health for sustainable agriculture and economic development in the region in future. 展开更多
关键词 Climate change ERODIBILITY indus basin Land degradation Slope stabilization
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Summer Atmospheric Water Cycle under the Transition Influence of the Westerly and Summer Monsoon over the Yarlung Zangbo River Basin in the Southern Tibetan Plateau
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作者 Qianhui MA Chunyan ZHANG +1 位作者 Donghai WANG Zihao PANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期830-846,共17页
This study compares the summer atmospheric water cycle,including moisture sources and consumption,in the upstream,midstream,and downstream regions of the Yarlung Zangbo River Basin in the southern Tibetan Plateau.The ... This study compares the summer atmospheric water cycle,including moisture sources and consumption,in the upstream,midstream,and downstream regions of the Yarlung Zangbo River Basin in the southern Tibetan Plateau.The evolutions of moisture properties under the influence of the westerly and summer southerly monsoon are examined using 5-yr multi-source measurements and ERA5 reanalysis data.Note that moisture consumption in this study is associated with clouds,precipitation,and diabatic heating.Compared to the midstream and downstream regions,the upstream region has less moisture,clouds,and precipitation,where the moisture is brought by the westerly.In early August,the vertical wet advection over this region becomes enhanced and generates more high clouds and precipitation.The midstream region has moisture carried by the westerly in June and by the southerly monsoon from July to August.The higher vertical wet advection maximum here forms more high clouds,with a precipitation peak in early July.The downstream region is mainly affected by the southerly-driven wet advection.The rich moisture and strong vertical wet advection here produce the most clouds and precipitation among the three regions,with a precipitation peak in late June.The height of the maximum moisture condensation is different between the midstream region(325 hPa)and the other two regions(375 hPa),due to the higher upward motion maximum in the midstream region.The diabatic heating structures show that stratiform clouds dominate the upstream region,stratiform clouds and deep convection co-exist in the midstream region,and deep convection systems characterize the downstream region. 展开更多
关键词 yarlung Zangbo River Basin atmospheric water cycle constrained variational analysis moisture source and consumption
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Greenhouse Gas Emissions from Agro-Ecosystems and Their Contribution to Environmental Change in the Indus Basin of Pakistan 被引量:8
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作者 M. Mohsin IQBAL M. Arif GOHEER 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第6期1043-1052,共10页
There is growing concern that increasing concentrations of greenhouse gases in the atmosphere have been responsible for global warming through their effect on radiation balance and temperature. The magnitude of emissi... There is growing concern that increasing concentrations of greenhouse gases in the atmosphere have been responsible for global warming through their effect on radiation balance and temperature. The magnitude of emissions and the relative importance of different sources vary widely, regionally and locally. The Indus Basin of Pakistan is the food basket of the country and agricultural activities are vulnerable to the effects of global warming due to accelerated emissions of GHGs. Many developments have taken place in the agricultural sector of Pakistan in recent decades in the background of the changing role of the government and the encouragement of the private sector for investment in new ventures. These interventions have considerable GHG emission potential. Unfortunately, no published information is currently available on GHG concentrations in the Indus Basin to assess their magnitude and emission trends. The present study is an attempt to estimate GHG (CO2, CH4 and N2O) emissions arising from different agro-ecosystems of Indus Basin. The GHGs were estimated mostly using the IPCC Guidelines and data from the published literature. The results showed that CH4 emissions were the highest (4.126 Tg yr^-1) followed by N20 (0.265 Tg yr^-1) and CO2 (52.6 Tg yr^-1). The sources of CH4 are enteric fermentation, rice cultivation and cultivation of other crops. N2O is formed by microbial denitrification of NO3 produced from applied fertilizer-N on cropped soils or by mineralization of native organic matter on fallow soils. CO2 is formed by the burning of plant residue and by soil respiration due to the decomposition of soil organic matter. 展开更多
关键词 greenhouse gases AGRICULTURE indus Basin Pakistan
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Recent snow cover variation in the Upper Indus Basin of Gilgit Baltistan, Hindukush Karakoram Himalaya 被引量:3
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作者 Hazrat BILAL CHAMHURI Siwar +1 位作者 MAZLIN Bin Mokhtar KASTURI Devi Kanniah 《Journal of Mountain Science》 SCIE CSCD 2019年第2期296-308,共13页
Mountainous basins like the Upper Indus Basin(UIB) of Gilgit Baltistan(GB) are dependent on seasonal snowmelt and glacier melt. Monitoring of the snow-covered area(SCA) is not only vital for the overall hydrology of t... Mountainous basins like the Upper Indus Basin(UIB) of Gilgit Baltistan(GB) are dependent on seasonal snowmelt and glacier melt. Monitoring of the snow-covered area(SCA) is not only vital for the overall hydrology of the Indus basin but also important to the sustainable agriculture and hydropower system. The snow-covered area in the UIB of GB was investigated for changes over the last 18 years using the Moderate Resolution Imaging Spectroradiometer(MODIS) snow product. The study area was divided into five elevation zones ranging from 877-8564 meters above sea level(m ASL). In contrast to the global cryosphere related studies, SCA in the UIB is slightly increasing. Elevation based SCA analysis also indicated that SCA is slightly increasing in each elevation zone. However, a significant amount of snow is concentrated in areas above 5000 m ASL. Due to the strong correlation between SCA and precipitation, the precipitation data also follow a similar trend. Analysis of the climatic data suggests a statistically significant increase in total monthly precipitation and relative humidity, a slight decrease in mean monthly temperature and a significant upward tendency in monthly solar irradiance data. All these trends in combination with the increasing trend in global precipitation, winter westerly disturbances and orographic precipitation are the important factors behind the slightly increasing SCA in the study area. Our results though constrained by short observation period mainly contribute to the understanding of advancing snow cover and glaciers in Hindukush Karakoram. 展开更多
关键词 Snow MODIS WESTERLY disturbances Climate change UPPER indus BASIN Glaciers
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Geochemistry and Depositional Setting of Fort Munro Formation,Middle and Lower Indus Basins,Pakistan 被引量:2
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作者 Shahid Naseem Shamim Ahmed Sheikh +1 位作者 Erum Bashir Khaula Shirin 《Journal of China University of Geosciences》 SCIE CSCD 2005年第2期160-169,共10页
Fort Munro Formation represents the products of the Upper Cretaceous (Maastrichtian) in the middle and lower Indus basins. The formation is exposed in the Rakhi Nala (Sulaiman Range), Bara Nala (Lakhi Range) and Naka ... Fort Munro Formation represents the products of the Upper Cretaceous (Maastrichtian) in the middle and lower Indus basins. The formation is exposed in the Rakhi Nala (Sulaiman Range), Bara Nala (Lakhi Range) and Naka Pabni (Southern Pab Range) areas. Major and trace elemental geochemistry and petrographic studies of the formation have been carried out to understand the facies trends in the middle and lower Indus basins. A high amount of acid-insoluble fraction, Ca/Mg and Mg vs. Ca/Sr ratio reveal that the formation was deposited in a shallow marine regressive environment. High amounts of clastic reflect abundant influx of terrigenous materials from the east (Indian craton) and west (Bibai volcanic). High Sr content indicates that aragonite was the precursor mineral, which was transformed into stable low-Mg calcite during diagenesis. Enrichment of Cu and Zn contents in the samples of the formation implies the influence of volcanic activity and that they were incorporated into the calcite lattice in the late phase. 展开更多
关键词 GEOCHEMISTRY depositional setting Fort Munro Formation middle and lower indus basins
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Tectonics induced switching of provenance during the Late Quaternary aggradation of the Indus River Valley, Ladakh, India 被引量:2
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作者 Ravish Lal H.S.Saini +1 位作者 N.C.Pant S.A.I.Mujtaba 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第1期285-297,共13页
The Indus River flows through Ladakh, one of the driest and coldest places on earth, in a tectonically active domain. Fluvial, glaciofluvial, lacustrine and debris dominated sequences represent the Late Quaternary sed... The Indus River flows through Ladakh, one of the driest and coldest places on earth, in a tectonically active domain. Fluvial, glaciofluvial, lacustrine and debris dominated sequences represent the Late Quaternary sedimentary record along the river course. Karakoram Fault, a major crustal scaled feature reported to be active during the Quaternary, is associated with the Indus River drainage. Linkages between a major, active fault and deposits formed during the activity period of the fault are explored using heavy mineral deduced provenance and Optically Stimulated Luminescence(OSL) chronology.Five deposits in a ~200 km long stretch of the Indus River have been examined for a ~80 ka period to decipher the climate linked aggradation history. Damming of the Indus River at ~79 ka and existence of the Spituk Lake for >30 ka is demonstrated. Using geology of the provenance in relation to the mineralogical attributes of the Quaternary deposits, the major drainage reorganization when the connection of the Tangtse Valley to the Indus was blocked, is inferred at ~73 ka. It is supported by the geologicalgeomorphological evidence. The study demonstrates the application of provenance linked mineralogy in terrestrial aggradation in a tectonically active region. 展开更多
关键词 Karakoram Fault indus Drainage reorganization Heavy minerals AGGRADATION
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Modelling the Spatial Distribution of Arsenic in Water and Its Correlation with Public Health, Central Indus Basin, Pakistan 被引量:1
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作者 Yawar Hussain Adil Dilawar +4 位作者 Sadia Fida Ullah Gulraiz Akhter Hernan Martinez-Carvajal Muhammad Babar Hussain Abdul Qayyum Aslam 《Journal of Geoscience and Environment Protection》 2016年第2期18-25,共8页
Like India, Bangladesh and China, Pakistan also has some regions where concentration of Arsenic in water has crossed the WHO safe drinking water limits, 10 ppb. Presence of Arsenic in drinking water is causing serious... Like India, Bangladesh and China, Pakistan also has some regions where concentration of Arsenic in water has crossed the WHO safe drinking water limits, 10 ppb. Presence of Arsenic in drinking water is causing serious human health issues for the local residents of Sindh and southern Punjab, which needs serious attention. The present study is focused on the spatial distribution of Arsenic in groundwater and its relationship with the major reported human diseases at settlement level of District Layyah. Data collection is done by taking water samples from hand pumps and health issues reported at the local health care centers adjoining to that sampling pump. The spatial distribution of Arsenic concentration in groundwater is done by using Inversion Distance Weight (IDW) technique. Arsenic Risk Index (ARI) is developed based of WHO health standards, and then used to divide study area into two Arsenic Risk Zones as no risk and high risk with As values less or equal to 10 ng·ml<sup>-1</sup> and greater than 10 ng·ml<sup>-1</sup>, respectively . In the final step these zones were correlated with the diseases at village level. The results show that, Arsenic is high near the Indus River and it decreases in central and eastern parts towards Chenab River. Same trend of Indo-Chenab Arsenic gradient is followed by skin diseases among the people especially, in tehsil Layyah and tehsil Koror. It is concluded that high Arsenic amount in water and skin diseases are highly dependent on the recharge from Indus River. 展开更多
关键词 ARSENIC GIS Human Health IDW indus Basin Layyah
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Exploration prospects of oil and gas in the Northwestern part of the Offshore Indus Basin, Pakistan 被引量:3
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作者 Jian-ming Gong Jing Liao +5 位作者 Jie Liang Bao-hua Lei Jian-wen Chen Muhammad Khalid Syed Waseem Haider Ming Meng 《China Geology》 2020年第4期633-642,共10页
Oil and gas resources are short in Pakistan and no commercially viable oil and gas sources have been yet discovered in its offshore areas up to now.In this study,the onshore-offshore stratigraphic correlation and seis... Oil and gas resources are short in Pakistan and no commercially viable oil and gas sources have been yet discovered in its offshore areas up to now.In this study,the onshore-offshore stratigraphic correlation and seismic data interpretation were conducted to determine the oil and gas resource potential in the Offshore Indus Basin,Pakistan.Based on the comprehensive analysis of the results and previous data,it is considered that the Cretaceous may widely exist and three sets of source rocks may be developed in the Offshore Indus Basin.The presence of Miocene mudstones has been proven by drilling to be high-quality source rocks,while the Cretaceous and Paleocene–Eocene mudstones are potential source rocks.Tectonic-lithologic traps are developed in the northwestern part of the basin affected by the strike-slip faults along Murray Ridge.Furthermore,the Cretaceous and Paleocene–Eocene source rocks are thick and are slightly affected by volcanic activities.Therefore,it can be inferred that the northwestern part of Offshore Indus Basin enjoys good prospects of oil and gas resources. 展开更多
关键词 Oil and gas CRETACEOUS Offshore indus Basin Oil storage structure Oil and gas engineering Pakistan
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Vegetation-environment relationship in conifer dominating forests of the mountainous range of Indus Kohistan in northern Pakistan 被引量:1
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作者 Adam KHAN Moinuddin AHMED +6 位作者 Muhammad Faheem SIDDIQI Mohib SHAH Eduardo Soares CALIXTO Afsheen KHAN Paras SHAH Javed IQBAL Muhammad AZEEM 《Journal of Mountain Science》 SCIE CSCD 2020年第8期1989-2000,共12页
Environmental variables play a crucial role in shaping vegetation structure,mainly in mountainous ecosystems.Different studies have attempted to identify the environment-vegetation relationship of Conifer Dominating F... Environmental variables play a crucial role in shaping vegetation structure,mainly in mountainous ecosystems.Different studies have attempted to identify the environment-vegetation relationship of Conifer Dominating Forests(CDF)worldwide.However,due to differences in local climate and soil composition,different environmental drivers can be found.By applying multivariate analysis techniques,this study investigated the vegetation-environment relationship of CDF of Indus Kohistan in northern Pakistan.Our results showed that CDF of Indus Kohistan are distributed in five distinct ecological groups,which are dominated by different trees and understory species.A total of 7 trees and 71 understory species were recorded from the sampling sites.Cedrus deodara was the leading species among four groups,having the highest importance value(IV),density and basal area.Group I was dominated by Pinus wallichiana with the second highest importance value,density and basal area.In addition,elevation,slope,maximum water holding capacity(MWHC),soil moisture(SM),total organic matter(TOM),sodium,phosphorus and nickel showed highly significant influence on composition and distribution pattern of Indus Kohistan vegetation.Therefore,this study shows a new evidence of vegetation-environment relationship,pointing out specific drivers of vegetation structure in CDF of Indus Kohistan region in northern Pakistan. 展开更多
关键词 Conifer forests Understory species Environmental variables Multivariate analysis indus Kohistan Northern Pakistan
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GIS/RS Based Monitoring of Coastal Region Using Aerial Photos and Satellite Images—A Case Study of Indus Delta
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作者 Naeem Shahzad Hammad Gilani +1 位作者 Urooj Saeed Kaif Gill 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期285-285,共1页
Globally,aerial photos and satellite images have been significantly used for the estimation and change analysis of different landcover features.In this study, change analysis has been performed along coastal extent of... Globally,aerial photos and satellite images have been significantly used for the estimation and change analysis of different landcover features.In this study, change analysis has been performed along coastal extent of the selected part of Indus Delta.The study successfully deals with the temporal mapping of sea invasion/land degradation,mangroves extent and agricultural patterns.Aerial photos of 1952 展开更多
关键词 indus DELTA MANGROVES AERIAL PHOTOS satellite images COASTAL line indus RIVER
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PLATINUM-GROUP ELEMENTS MINERALIZATION IN THE OPHIOLITES OF INDUS SUTURE ZONE, EASTERN LADAKH,THE HIMALAYA
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作者 N.Siva Siddaiah\+1, A.Masuda\+2 2 Department of Chemistry,The University of Electro\|Communications,Chofu,Tokyo 182,Japan) 《地学前缘》 EI CAS CSCD 2000年第S1期428-429,共2页
Platinum\|Group Elements (PGE) along with other highly siderophile elements (HSE) are quantitatively fractionated into the core and mantle,leaving the crust strongly depleted during the formation of the earth.However,... Platinum\|Group Elements (PGE) along with other highly siderophile elements (HSE) are quantitatively fractionated into the core and mantle,leaving the crust strongly depleted during the formation of the earth.However,the transfer of PGE and other HSE from the mantle may occur by tectonic emplacement of mantle material into the crust or by crystallization of the mantle derived magma in the crust.The formation and emplacement of ophiolites,is therefore,a suitable transfer mechanism in the enrichment of PGE and other metallic mineral deposits.Because of this,in recent years,a great deal of attention is being paid in studying the ophiolites in order to better understand the core\|mantle interaction,chemical evolution of the upper mantle and to explore their noble metal potential.The ophiolites along the Indus Suture Zone (ISZ) in the Himalayas are tectonically related to India\|Eurasia collision.But their detailed geochemical evolution history and economic potentiality (chromite,PGE,gold and Ni\|sulfides) is not evaluated so far.Nidar ophiolite of the eastern Ladakh is one of the ophiolitic suites along the ISZ.The general geology of the area was presented in several research papers.This paper presents the geology,mineralogy and geochemistry of the chromitites and reports on the first platinum\|group elements mineralization to have been discovered. 展开更多
关键词 PGE concentrations Nidar OPHIOLITE indus SUTURE Zone Him alayas
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Structural and Stratigraphical Correlation of Seismic Profiles between Drigri Anticline and Bahawalpur High in Central Indus Basin of Pakistan
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作者 Shazia Asim S. N. Qureshi +3 位作者 Summyia Khatoon Asif Shabeer Ahmed Abbasi Sarfraz Solangi M. Qasim Mirza 《International Journal of Geosciences》 2014年第11期1231-1240,共10页
Publicly available seismic and well data are used to study the subsurface structure and stratigraphy of an area on the southern margin of the Central Indus Basin (CIB), Pakistan. Study area includes southern parts of ... Publicly available seismic and well data are used to study the subsurface structure and stratigraphy of an area on the southern margin of the Central Indus Basin (CIB), Pakistan. Study area includes southern parts of the Punjab Platform and Sulaiman Foredeep tectonic units of the CIB. A regional scale East-West depth cross-section is prepared in South of hydrocarbon bearing Safed Koh Trend to Punjab Platform. It gives the structural configuration of various formations of Paleozoic-Cenozoic times. Reflectors are marked and correlated with the help of wells Drigri-01 and Bahawalpur East-01, located on seismic lines 914-RPR-03 and 916-YZM-05 respectively. These reflectors/formations are correlated with respect to ages to avoid the confusions as there are many truncations in the area. Average velocities are used for the depth computation. Depth cross-section (AB) shows that Punjab Monocline is a stable area with a shallow basement. In Punjab Platform all the formations dip gently to the West. Then they attain steep dips in the Sulaiman Foredeep/Depression area. Depth cross-section along the Drigri anticline which lies in the SE of Sakhi Sarwar anticline reveals that it is extended E-W over 17 km approx. and the reverse faults are present on both flanks of a fold, due to that a pop up structure is formed. It’s a low amplitude fold, as it marks the southern end of Safed Koh Trend (first line of folding of the folded flank of Sub-Sulaiman Fore Deep). Subsurface structural variations at Bahawalpur show a buried high of Jurassic-Permian age. A sedimentary cover is 9 km thick in West and 3 m thick in East. Basement is uplifted at Bahawalpur High. 展开更多
关键词 SEISMIC Interpretation CENTRAL indus BASIN Burried RIDGE
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