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1.
Qureshi  J.  Mahmood  S. A. 《Geotectonics》2021,55(4):618-632
Geotectonics - In our research paper, new observations and results of the Central Suleiman fold-and-thrust belt (CSFTB) that highlights the topographic evolution and active deformation in this...  相似文献   
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Understanding the level of connectivity between estuarine and coastal waters is essential for appropriate management of estuarine-associated taxa. Most studies have focused on the role of a single estuary, while limited research exists on the importance of multiple estuaries to individuals of estuarine-associated species. This study used acoustic telemetry to assess the usage of multiple estuaries and coastal waters by the estuarine-dependent spotted grunter Pomadasys commersonnii. Twenty-six adult fish were tagged with acoustic transmitters in the Kariega and Bushmans estuaries, South Africa, and their movements along a 300-km stretch of Indian Ocean coastline were monitored for up to 17 months. Tagged individuals spent most of their time in the estuary where they were tagged (55% and 85% for fish tagged in the two estuaries, respectively), followed by time in the sea (30% and 15%) and in other estuaries (15% and <1%). The mean durations of sea trips for fish tagged in the Kariega Estuary or Bushmans Estuary, respectively, were 25 days (range 3–55) and 12 days (range 2–22). Of the fish that went to sea, 93% from the Kariega Estuary and 60% from the Bushmans Estuary visited other estuaries. Most visits were undertaken to the Swartkops, Bushmans and Kowie estuaries, although the longest durations were spent in the Sundays Estuary. Individuals moved to estuaries up to 130 km away. The total distance travelled between estuaries by an individual during the study was ~529 km, with means of 201 and 184 km, respectively, for fish tagged in the Kariega and Bushmans estuaries. Despite covering large distances between estuaries, individuals often returned to their tagging estuary. Residency in their tagging estuary, combined with frequent visits to a neighbouring estuary, highlights the importance of estuarine habitats for this popular fish species, even after reaching maturity.  相似文献   
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Theoretical and Applied Climatology - Analysis of climatic variables is important for the detection and attribution of climate change trends and has received considerable attention from researchers...  相似文献   
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"Metropolitanisation has been observed by experts as one of the main characteristics of Indian urbanisation. Rural to urban migration has been a major player in urban growth of metropolitan cities, particularly Delhi. Not only Delhi but its hinterland [are] urbanising fast as compared to the hinterlands of other major cities of India. There are several processes of urbanization viz. historical, physical, demographic and economic. In this paper the role of demographic processes in urban expansion of Delhi [is examined]."  相似文献   
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豫西沙沟脉状Ag-Pb-Zn矿床地质特征和成矿流体研究   总被引:6,自引:1,他引:5  
豫西沙沟薄脉状Ag-Pb-Zn硫化物矿床位于华北陆块南缘熊耳山地区,主要由多金属硫化物-石英-碳酸盐脉型和石英-碳酸盐-绢云母-多金属硫化物蚀变岩型两种矿化类型组成。主要矿脉的矿物共生序列可以分为成矿前的石英-黄铁矿阶段(Ⅰ)、闪锌矿-石英-方铅矿-少量银矿物阶段(Ⅱ1)、方铅矿-石英-闪锌矿-含铁白云石-银矿物阶段(Ⅱ2)和成矿后的方解石-(石英)阶段(Ⅲ)。对不同阶段的成矿流体研究表明,石英-黄铁矿阶段(Ⅰ)中的含氯化钠子晶三相(LVH)包裹体(Ⅰ1)可能是直接从饱和水的结晶岩浆熔体中出溶形成或是由岩浆流体的减压沸腾形成,显示该区很可能存在岩浆流体端元。多金属硫化物阶段(Ⅱ1Ⅱ2)捕获富液相包裹体(LV型)和个别CO2包裹体(C型),这两个阶段流体包裹体反映了主成矿阶段流体的基本特征,结合包裹体气相和液相成分色谱分析以及包裹体初融温度,认为成矿流体应该为中-低温低盐度含CO2的H2O-NaCl体系。其中,阶段(Ⅱ2)的均一温度(145~288℃,平均为194℃)比阶段(Ⅱ1)的均一温度(185~357℃,平均240℃)低46℃;同时,阶段(Ⅱ2)的盐度(1.91%~10.86%,平均6.38%)较阶段(Ⅱ1)盐度(4.65%~10.11%,平均7.77%)略低。对这一温度和盐度的总体下降趋势的合理解释是大气水的逐渐混入。多金属硫化物阶段(Ⅱ1Ⅱ2)之后的方解石-(石英)阶段普遍为富液相包裹体(LV型),该阶段显著降低的温度(129~208℃,平均165℃)和盐度(1.40%~4.03%,平均2.50%),进一步佐证大气水的不断混入。而且,流体混合可能在引起矿石矿物从热液中沉淀方面起到重要作用。  相似文献   
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This paper examines the interrelationships and interactions of the geomorphic features and the various hydrological parameters which control the development of water potential zones in the central Luni basin. Aerial photo-interpretation techniques were used to delineate the boundaries of geomorphological features, and facilitated the identification of twelve types of aquifers in eight geomorphological settings. The water potentials of these aquifers have been evaluated by taking into consideration nine important hydrological parameters which together govern water quality and yield. This investigation has revealed that the development of zones of ground-water potential is principally governed by the geomorphic characteristics of the terrain, which in turn is controlled by lithological variability, geological structure, drainage pattern, climatic characteristics, etc. The relevance of geomorphic characteristics has been evaluated by weight point analysis. Based on these findings, it is suggested that detailed studies of geomorphic features are of paramount significance for the rapid delineation of possible ground-water potential zones in arid and semi-arid regions.  相似文献   
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