If the Himalayas are a land of extremes from the topographical, geophysical and geological point of view (Windley 1984, 1988), the Karakorum is a land of superlative, having the highest concentration of mountains beyond 8000 m, having the longest glaciers beyond the poles, being the source of one of the longest rivers. From the geophysical point of view it contains the largest gravity anomalies (Poretti et al. 1983) and thickness of the earth crust (75 km) (Finetti et al. 1978, 1983) and the highest values of deflection of the vertical. It contains also the highest relief (4000 m from the Indus plains to the summit of Nanga Parbat). It seems also that this area is subjected to the highest uplift. This has been mentioned by many authors deriving it through indirect methods, but not yet confirmed by accurate direct observations. Owen (1981) reports 0.7 mm/year using fission-track methods. Higher values (2 mm/year) are inferred by several researchers (Zeitler 1985; Gorniz and Seeber 1981; Lyon-Caen and Molnar 1983; Ferguson 1985; Owen 1989). Finally an average value of 6-10 mm/yr is in the hypothesis of Zeitler et al. (1985) including uplift and erosion. The present study presents the preliminary results of a first survey consequent to the recent installation (2009) of GNSS network including three permanent GNSS stations between Islamabad and the northern areas of Pakistan and four points located on the Nanga Parbat-Haramosh massif. since a permanent GPS station was located near the Pyramid Laboratory at Lobuche in the Khumbu region in 1994 providing long records of data during the last 15 years; the goal of the project is to compare data obtained from Everest with the ones from Nanga Parbat in order to evaluate, not only the total uplift (if quantifiable) of the two massifs, but also the direction of the crustal movements.
Comparison between the tectonic movements of Mt Everest and the Nanga Parbat-Haramosh Massif.
PORETTI, GIORGIO;CALLIGARIS, CHIARA;
2010-01-01
Abstract
If the Himalayas are a land of extremes from the topographical, geophysical and geological point of view (Windley 1984, 1988), the Karakorum is a land of superlative, having the highest concentration of mountains beyond 8000 m, having the longest glaciers beyond the poles, being the source of one of the longest rivers. From the geophysical point of view it contains the largest gravity anomalies (Poretti et al. 1983) and thickness of the earth crust (75 km) (Finetti et al. 1978, 1983) and the highest values of deflection of the vertical. It contains also the highest relief (4000 m from the Indus plains to the summit of Nanga Parbat). It seems also that this area is subjected to the highest uplift. This has been mentioned by many authors deriving it through indirect methods, but not yet confirmed by accurate direct observations. Owen (1981) reports 0.7 mm/year using fission-track methods. Higher values (2 mm/year) are inferred by several researchers (Zeitler 1985; Gorniz and Seeber 1981; Lyon-Caen and Molnar 1983; Ferguson 1985; Owen 1989). Finally an average value of 6-10 mm/yr is in the hypothesis of Zeitler et al. (1985) including uplift and erosion. The present study presents the preliminary results of a first survey consequent to the recent installation (2009) of GNSS network including three permanent GNSS stations between Islamabad and the northern areas of Pakistan and four points located on the Nanga Parbat-Haramosh massif. since a permanent GPS station was located near the Pyramid Laboratory at Lobuche in the Khumbu region in 1994 providing long records of data during the last 15 years; the goal of the project is to compare data obtained from Everest with the ones from Nanga Parbat in order to evaluate, not only the total uplift (if quantifiable) of the two massifs, but also the direction of the crustal movements.Pubblicazioni consigliate
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