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731.
Riyaz Ahmad Mir Sanjay K. Jain Arun K. Saraf Ajanta Goswami 《Journal of the Indian Society of Remote Sensing》2014,42(1):91-105
Himalayan glaciers and their mass balance are poorly sampled through direct mass balance measurements. Thus, based on Landsat datasets of ETM+ (2000), ETM+ (2006) and TM (2011), mass balance studies of 32 glaciers was carried out using accumulation area ratio (AAR) method in the Tirungkhad river basin, a tributary of Satluj River, located in western Himalayan region. The overall specific mass balance was negative varying from ?27 cm (2000) to ?41 cm (2011). Out of 32 glaciers, 27 glaciers (81.2 %) showed negative mean mass balance and 5 glaciers (18.7 %) showed positive mean mass balance. Mean of specific mass balance for the year 2000, 2006 and 2011 was found to be ?48 cm, ?55 cm and ?0.61 cm respectively, in case of glaciers with negative mass balance while in case of glaciers with positive mass balance, it was 0.67 cm (2000), 0.56 cm (2006) and 0.47 cm (2011). The investigations suggested a loss of ?0.034 km3 of glacial ice for 2000, 0.036 km3 for 2006 and 0.038 km3 for 2011 respectively. The negative mass balance of the glaciers since 2000 correlates well with the increasing trend of annual mean temperature and decreasing trend of precipitation (snow water equivalent (SWE) and rainfall). Based on Mann Kendall test the temperature and SWE trends were significant at 95 % confidence level, however, the rainfall trend was insignificant. 相似文献
732.
China Ocean Engineering - The breakwaters have experienced many changes during their construction history. These changes have been considered to improve their performance, depending on their... 相似文献
733.
The Kachchh Basin is a pericratonic rift basin situated at the western margin of the Indian plate. The Habo Dome embodies
an important exposure of Bathonian to Kimmergian sediments among the Kachchh Mainland exposures. Based on vertical facies
transitions, facies associations were documented: mixed shallow marine (Facies association 1), shoreface and lagoon deposits
(Facies association II) and subtidal innershelf below fair weather wave base (Facies association III). The documented facies
associations reflect that Habo Dome sediments deposited in a variety of environments from shallow marine to fluvio-deltaic
and were strongly influenced by fluctuation of relative sea level. The dominance of floating grains and point contacts in
the sandstone indicate that detrital grains do not show much pressure effects as a result of either shallow burial or early
cementation. The sandstones were cemented by iron oxide, carbonate and silica in order of abundance. Three types of cements,
blocky, rim and fibrous cement occur in the studied limestone representing phreatic, fresh water phreatic and deep burial
diagenetic stages. Neomorphism and micritization are common. Both primary and secondary porosity exists in these sediments.
Different graphs of porosity versus depth suggest a depth of burial in the range of 615–769 m. 相似文献