Localized high-grade metamorphic terranes exposed within orogenic belts offer a unique opportunity to examine rocks which were once at great depths and which have enjoyed the various orogenic phases. ...Many of these terranes are thought to have developed rapidly, exhumed during the late- to post-orogenic stages. The Nanga Parbat-Haramosh massif, western Himalayan syntaxis, exemplifies such a feature. A multidisciplinary approach, with an emphasis on geo- and thermochronology and field observations, allows the tectonic evolution of the massif to be tightly constrained. The Indian plate rocks which constitute the Nanga Parbat massif initially underwent Eocene metamorphism and Miocene anatexis as a result of collision between India, a juvenile island are, and Asia at about 60 Ma. Indian plate metasedimentary rocks across the western syntaxial region, near Nanga Parbat and Hazara, yield Oligocene mica cooling ages suggesting these rocks were in the shallow crust by that time. Crustal-scale transpression as a result of India-Asia collision and dextral slip along the Karakourm fault created a series of off-stepping domes in the western syntaxial region, upwarping Indian crust and forming the beginnings of the present-day massif. Not only manifested as structural domes, the Late Miocene occurrence is also observed in isotopic signatures. U-Th-Pb crystallization ages on accessory minerals from metamorphic and plutonic sequences along the flanks of Nanga Parbat and at Haramosh indicate heating and related anatexis from 13 Ma to 9.5 Ma. Ar-Ar analyses on medium-closure temperature silicates indicate cooling was concurrent with doming; these patterns are preserved at Haramosh and in the Karakorum, to the north and east. The Nanga Parbat massif, however, has been subsequently overprinted by a distinct high-grade petrologic and structural event. This Plio-Pleistocene episode appears to be spatially restricted to Nanga Parbat (sensu stricto) and has resulted in the formation of 3 Ma migmatites, 1 Ma granites, and recent, rapid exhumation and cooling. Granites are suggested to have formed by vapor-absent crustal melting as a result of this rapid decompression as well as local melting via fluid infiltration through shear zones. Exhumation is dominated by erosion, with an apparent lack of any crustal-scale, normal-motion detachment. Structural modification of Nanga Parbat is primarily accomplished through a pair of conjugate thrust-displacement shear zones, defining a crustal scale antiformal “pop-up structure”, consistent with models predicting doubly-vergent orogen structures/geometries. The shear zones have a spatial and temporal association with magmatism, beginning probably with the Late Miocene doming event and continuing today. The evolution suggested here for Nanga Parbat indicates that, although the most recent episode has significantly overprinted signatures of previous events, the massif has had a protracted tectonic history, characterized by at least three episodes involving melting and deformation, and is not the product of a single, late-orogenic event. Other gneiss dome-type structures in orogenic belts may have an analogous evolution and should be evaluated in a similar manner.
Various manifestations of large-scale slope processes are described. Though many of them are prehistoric they exemplify the phenomena that have the highest potential to cause a humanitarian, economic ...or environmental catastrophe. They are described, based on the contributions of the 1st WLF participants.
Karte der Nanga-Parbat-Gruppe : Deutsche Himalaya-Expedition 1934 / hrsg. i.A. ... vom Reichsminister für Wirtschaft, Erziehung und Volksbildung ... - 1:50 000 Schichtlinienabstand 50 Meter
München : ...Klein & Volbert , 1937. - 1 Kt. : mehrfarb., 70 x 92 cm. - Mit Höhenlinien
in color
Map of the Nanga Parbat Group: German Himalayan Expedition 1934/hrsg. I... by the Reich Minister for Economic Affairs, Education and People’s Education... - 1: 50.000 shift line spacing 50 meters
Munich: Klein & Volbert, 1937. - 1 Kt. : multicolored., 70 x 92 cm. - With elevation lines
in color
A 1985 survey at Rakhiot Glacier, Nanga Parbat, Punjab Himalaya, indicates that the glacier terminus is advanced about 200 m from its 1954 position. Between 1930 and 1954, the dates of previous ...surveys, the glacier terminus had thinned and back-wasted 450 m. The recession prior to the 1960s, followed by advance into the 1970s and perhaps 1980s, parallels patterns of glacier fluctuation found in the adjacent western and central Karakorum.
Two new occurrences of HP rocks have been found in the Indus suture zone on the eastern side of the Nanga Parbat-Haramosh massif: a retrogressed eclogitic assemblage in pyroxenitic boudins within the ...Ladakh island-arc sequence, and an HP granulitic paragenesis in mafic alternations of High Himalaya banded gneisses. PT estimates on five samples with garnet-clinopyroxene-amphibole-plagioclase-quartz-FeTi oxide-biotite mineral assemblage have respectively yielded 13 ± 1 kbar for 610 ± 30 °C, and 10 ± 1 kbar for 700 ± 50 °C. This metamorphism is linked to the continuous subduction of continental and arc material after India-Eurasia collision. The granulitic retrogression corresponds to a phase of collage, with prograde granulites during exhumation.
Deux nouveaux indices de roches de HP ont été découverts dans la zone de suture de l'Indus, sur le flanc est du massif du Nanga Parbat — Haramosh: un assemblage éclogitique rétromorphosé en granulite dans des boudins pyroxéniques de la séquence de l'arc du Ladakh, et un assemblage granulitique HP dans des niveaux basiques de gneiss himalayens rabanés. L'estimation des conditions PT sur cinq échantillons présentant la paragenèse grenat-clinopyroxène-amphibole-plagioclase-quartz-oxyde Fe, Ti-biotite, a donné une pression minimale de 13 ± 1 kbar pour 610 ± 30 °C sur les éclogites, et 10 ± 1 kbar pour 700 ± 50 °C sur les granulites. Ce métamorphisme HP est dû à la poursuite de la subduction des matériaux du continent indien et de l'arc insulaire après la collision Inde-Eurasie. La rétromorphose en facies granulite correspond à une phase de collage avec des granulites progrades, du matériel éclogitique en cours d'exhumation.
The mapping and measurement of glaciers and their changes are useful in predicting sea‐level and regional water supply, studying hazards and climate change Haeberli et al., 1998,and in the hydropower ...industry Existing inventories cover only about 67,000 of the world's estimated 160,000 glaciers and are based on data collected over 50 years or more e.g.,Haeberli et al., 1998. The data available have proven that small ice bodies are disappearing at an accelerating rate and that the Antarctic ice sheet and its fringing ice shelves are undergoing unexpected, rapid change. According to many glaciologists, much larger fluctuations in land ice—with vast implications for society—are possible in the coming decades and centuries due to natural and anthropogenic climate change Oppenheimer, 1998.
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