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Geotechnical engineering applications comprises high temperature such as deep geological disposal of nuclear waste, exploitation of geothermal process, etc. High temperature and thermal environments can affect the mechanical properties of building materials used in civil engineering (concrete, building rock, steel, etc.). The constant action of regular thermal changes in situations of excess temperature is the main source of the alteration of marble in monumental and artistic buildings. In this study, the effect of both the specimen size and temperature on the physio-mechanical characteristics of dolomitic marble has been investigated. The temperature range selected was 20-600°C. It was observed that the color of samples changes with temperature rise. The Uniaxial compression strength (UCS), P-wave velocity (Vp), and Young's modulus decreased with temperature rise. While the peak strain increases with temperature. The UCS and the peak strain showed a decreasing trend at the high diameter specimens. In the case of 43mm diameter specimens the peak stress reduced from 60MPa-26MPa with a rise in temperature from 20-600°C. While at the same temperature range the peak strain was observed as 1.7-3.3 and Young's modulus was 34-8GPa. For 75 mm diameter, the peak stress is reduced to 17MPa when the temperature rises to 600°C and Young's modulus decreased to 4GPa while the peak strain increased from 2.3 to 3.9. The pulse velocity decreased from 2.75 km/s to 0.8km/ and the porosity value increased from 0.9 to 1.5%. [ABSTRACT FROM AUTHOR]

Gilgit-Baltistan is known for the extraction of placer gold as well as base metals however, no significant work has been done to investigate the host rock. This study is mainly focused on identification of the host rock for metallic minerals of Gindai Yasin, Ghizer district of Gilgit Baltistan, located towards south-west of the Main Karakorum Thrust (MKT), a mega thrust separating Kohistan Island Arc from the Karakoram plate. The Shamaran volcanics consist of heterogeneous basaltic-andesite to andesite and calc-alkaline rock units. Petrographic results indicate that, the rocks of mineralised zone are felsic to mafic in composition, optical analysis showed that these rocks had gone through extrusive hydrothermal alteration. The rocks mostly comprised of metallic minerals include chalcopyrite, malachite, pyrite and azurite. From the geochemical analysis, a significant portion of the sample is basaltic-andesite to andesite in composition, and mineralised zones are mafic to ultramafic. Gold and copper concentrations varies from 2.43-4.76 ppm, and 26800-98600ppm respectively. [ABSTRACT FROM AUTHOR]

The hydrologiest are debating on the rise in global glacier melting. However, the situation in Karakoram glaciers seems not the same. Therefore, it is essential to measure the status of snow in the Karakoram region of (GB; Gilgit-Baltistan) Pakistan. To this end, the current study examines the dynamics of snow cover using Moderate Resolution Imaging Spectroradiometer (MODIS) 8-days sow-cover in response to in-situ meteorological indicators from four high altitude automatic weather stations in Upper Indus Basin (UIB). The results conclude that the 8-days snow cover images not only show the qualities of MODIS (high resolution) images it's also characterized the high accuracies for snow-cover classification (~85 to 95 %). We analysed the snow-cover dynamics in the UIB and computed the maximum quantity of snow cover days (SCD) in a year that shadowed an increasing trend from 2000-2014, with an increase in snow-covered area (SCA) of 45.04% to 59.26% of the total land area of GB. Besides, there is a slightly decreasing trend observed in the SCA of Hindukush, and Himalayan mountains region in the last 15 years, due to increases in temperature and precipitation. Spearman's correlation analysis is also obtained between monthly and annually snow-cover changes (snow accumulation /depletion over six elevation zones above 2000 m elevation) and temperature. The month of January shows decreasing trends for five elevation zones out of six zones below 6000 m elevation. In spring, particularly in March shows a decreasing trend for two zones above 5000m elevations, while shows increasing trend in autumn for three zones above 4000 m elevation. A negative trend observed between monthly SCA and Khunjerab area (mean temperature and precipitation), and similar results are also noted for the remaining three regions such as Deosai, Naltar and Shandoor of UIB. The study suggests that, in the UIB region, climate change also employ a significant influence on regional SCA and days, as well as the distribution of snow-cover. These findings help for the forecasting of seasonal flow in the area and signifying snow-cover as a possible predictor of climate change. [ABSTRACT FROM AUTHOR]

This study is an attempt to quantify the indoor and outdoor gamma radiation level, the associated effective dose rate and Lifetime Cancer Risk in Gahkuch, the capital city of district Ghizer in the eastern Hindukush. All measurements have been carried out by FAG radiation dose rate meter in representative houses made of different construction materials. These measurements were performed at standard height of 1 meter above the ground level. The mean absorbed dose rate was 229.5 nGy/h for indoor and 220.6 nGy/h for outdoor environments, which is greater than global level. Annual Effective Dose for indoor were determined as 1.0 mSv/y while for outdoor its value was 0.4 mSv/y, which differs to the average worldwide value of 0.48 mSv/y. Average Excess Lifetime Cancer Risk was found to be 3.4×10-3 for indoor while it was 1.4×10-3 for outdoor. Both of these values are higher than the World average value 0.29×10-3. The current study shows that Gahkuch, Ghizer is placed in those regions where a remarkably high dose rate exists. [ABSTRACT FROM AUTHOR]

In this study, marble samples were collected from a quarry near the Karakoram Highway, and core samples were prepared for direct compressive strength, indirect strength, pulse velocity, and Schmidt hammer value testing. The study revealed a strong linear relationship between the point load index (PLI) and uniaxial compressive strength (UCS) for both dry and saturated samples, demonstrating the predictive value of PLI, especially in dry conditions. However, it is important to note the reduced reliability of this relationship in saturated samples, which is likely due to factors such as pore water pressure. An exponential relationship was also observed between ultrasonic pulse velocity (Vp) and UCS, with most samples exhibiting lower Vp values than the typical marble average. This suggests variations in the subsurface structure of the marble and warrants further investigation to understand its mechanical implications. The linear correlation between the degree of weathering and Schmidt hammer readings offers a practical method for assessing weathering conditions. Grade I marble exhibited Schmidt hammer rebound values greater than 45, while values ranged between 35 and 45 for Grade II and were less than 35 for Grade III. The stress-strain curve revealed a decrease in peak stress (from 60 MPa to 32 MPa) with saturation. These results enhance the understanding of Ghulmet marble's mechanical behavior and its suitability for diverse applications, emphasizing the importance of considering varying conditions and characteristics in geotechnical assessments. [ABSTRACT FROM AUTHOR]