Reconstruction of the Ice Age Glaciation in the Southern Slopes of Mt
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Journal of Mountain Science Vol 3 No 2 (2006): 91~124 http:// jms.imde.ac.cn; http://www.imde.ac.cn/journal Article ID: 1672-6316 (2006) 02-0091-34 Reconstruction of the Ice Age Glaciation in the Southern Slopes of Mt. Everest, Cho Oyu, Lhotse and Makalu (Himalaya) (Part 1) Matthias Kuhle Geographie/Hochgebirgsgeomorphologie, Geographisches Institut der Universität, Goldschmidtstr.5, 37077 Göttingen, Germany E-mail: [email protected] Tel.: + 49 (0) 551 39 8067; Fax: +49 (0) 551 39 7614 Editorial Note: All the serious scientific issues are generally and finally recognized through repeated explorations, many examinations and various debates among different views. The research on past glaciations of the Himalayan Mountains and the Tibetan Plateau has been considered not only an interesting and valuable hot spot, but also a controversial issue. As a scientific and technological platform for exchanging information on mountain research and development, the JMS provides an equal chance for publishing different ideas and opinions from different schools of thought. Prof. Matthisa Kuhle has long worked on research on the past glaciations in the High Asia and achieved a series of results. The contribution entitled “Reconstruction of the Ice Age Glaciation on the Southern Slopes of Mt. Everest, Cho Oyu, Lhotse and Makalu (Himalaya)” is one of his research results, and we are greatly interested in it. No matter whether his result or conclusion is correct or not, his spirit to actively take part in and devote himself to the glaciological research is admired by us. However, as a distinctive theory, his article is worth reading. We hope that its publication will arouse responses and contends among colleagues in the circle of mountain science. The original manuscript was too long with so many figures. Though the author condensed the text and reduced the figures to 30 as we proposed, the article is still very long for being published by a journal. So, we decide to publish it separately in two issues (No. 2~3, Vol. 3). The section for this issue (No. 2, Vol. 3) of the JMS, including 8 Figures and 6 Tables, is the first part of the article. The figures after No. 8 cited in the text of this part will be arranged in the next issue for the convienience of composition (No. 3, Vol. 3). We sincerely apologize to you for any inconvenience this arrangement may have caused you. Abstract: In the Khumbu- and Khumbakarna system of the Himalaya and has communicated across Himalaya an ice stream network and valley glacier transfluence passes with the neighbouring ice stream system has been reconstructed for the last glacial networks toward the W and E. The ice stream network period (Würmian, Last Ice Age, Isotope stage 4-2, 60- has also received inflow from the N, from a Tibetan 18 Ka BP, Stage 0) with glaciogeomorphological and ice stream network, by the Kyetrak-Nangpa-Bote sedimentological methods. It was a part of the glacier Koshi Drangka (Valley) in the W, by the W-Rongbuk glacier valley into the Ngozumpa Drangka (Valley), by the Central Rongbuk glacier valley into the Khumbu Received: 18 January 2006 Drangka (Valley) and by the antecedent Arun Nadi Accepted: 28 March 2006 91 Matthias Kuhle transverse-valley in the E of the investigation area. focused on the evidence of glacier trim-lines and The ice thickness of the valley glacier sections, the -thicknesses. surface of which was situated above the snow-line, This is the regional continuation of a detailed amounted to 1000~1450 m. The most extended and spatially extensive reconstruction of the Ice parent valley glaciers have been measured approx. 70 Age glaciation in High Asia. It completes the km in length (Dudh Koshi glacier), 67 km (Barun- author's research on the past extent of ice and Arun glacier) and 80 km (Arun glacier). The tongue glacier thicknesses in High Asia carried out since end of the Arun glacier has flowed down to c. 500 m and that of the Dudh Koshi glacier to c. 900 m asl. At 1973 and published since 1974 (Kuhle M. heights of the catchment areas of 8481 (or 8475) m 1974~2005) by further observations in areas which (Makalu), i.e., 8848 (or 8872) m (Mt. Everest, have already been studied earlier or which have not Sagarmatha, Chogolungma) this is a vertical distance yet been visited (Figures 1, 2(insert between p. of the Ice Age glaciation of c. 8000 m. The steep faces 94&95), 3, 16). towering up to 2000 m above the névé areas of the 6000~7000 m-high surfaces of the ice stream network were located 2000~5000 m above the ELA. 1.1 Methods Accordingly, their temperatures were so low, that their rock surfaces were free of flank ice and ice balconies. From the maximum past glacier extension The geomorphological and Quaternarygeo- up to the current glacier margins, 13 (altogether 14) locical methods applied in the field and laboratory glacier stages have been differentiated and in part have already been discussed in detail in the papers 14C-dated. They were four glacier stages of the late on empirical Ice Age research and the glaciation glacial period, three of the neoglacial period and six of history of High Asia (Kuhle M. & WANG Wenjing the historical period. By means of 130 medium-sized 1988, Kuhle M. & XU Daoming 1991, Kuhle M.1994, valley glaciers the corresponding ELA-depressions 1997a, 1999a, 2001a) published in the GeoJournal have been calculated in comparison with the current series “Tibet and High Asia — Results of Investiga- courses of the orographic snow-line. The number of tions into High Mountain Geomorphology, Paleo- the glacier stages since the maximum glaciation Glaciology and Climatology of the Pleistocene (Ice approx. agrees with that e.g. in the Alps and the Age Research)” and “Glaciogeomorphology and Rocky Mountains since the last glacial period. Prehistoric Glaciation in the Karakorum and Accordingly, it is interpreted as an indication of the Würmian age (last glacial period) of the lowest ice Himalaya” Volumes I (1988), II (1991), III (1994), margin positions. The current climatic, average IV (1997a), V (1999a) and VI (2001a). Accordingly, glacier snow-line in the research area runs about these scientifically common methods are only 5500 m asl. The snow-line depression (ELA) of the introduced here in general. Glaciogeomorphologic last glacial period (Würm) calculated by four methods observations in the research area (Figures 1, has run about 3870 m asl, so that an ELA-depression 2(insert between p. 94&95), 16) have been mapped. of c. 1630 m has been determined. This corresponds Locations of typologically unambigous individual to a lowering of the annual temperature by c. 8, i.e., phenomena, i.e., glacier indicators, have been 10℃ according to the specific humid conditions at recorded with the help of 39 signatures (Figures 1, that time. 2(insert between p. 94&95), 16). The catalogue of signatures applied has especially been developed by the author for the base map 1:1 million (ONC 1 Introduction, Methods of Evidence and H-9, 1978 and 1:50 000 Khumbu Himal Schneider Characteristics of the Investigation 1978). The locations of sediment samples, from Areas which only a selection could be taken in consideration for this paper, have also been The aim of this study was to find geomorph- marked. All type localities are presented in Figure 1 ological and sedimentological indicators of a past and Figure 2(insert between p. 94&95). They glaciation. In addition to the reconstruction of the concern areas in which the arrangement of the maximum extent of Ice Age glacier cover, field positions of the indicators provides unambiguous investigations combined with panorama photo- evidence of the Ice Age glacier cover. Reference to graphs and laboratory analyses of samples were them are given in the text, in the photographs, 92 Journal of Mountain Science Vol 3 No 2 (2006) Figure 1 Quaternary-geological and glacio-geomorphological map 1:700 000 of the Khumbu- and Khumbakarna Himal (Cho Oyu-, Mt.Everest- (Chogolungma- i.e., Sagarmatha-) and Makalu massifs) in the Central Himalaya. See Figure 2(insert between p. 94&95) and Figure 3. 93 Matthias Kuhle Figure 3 Map 1:700 000 with localities of the glacio-gemorphological and -sedimentological valley cross-profiles during the maximum Ice Age glaciation in the Khumbu- and Khumbakarna Himal between Makalu (8481 m) and Cho Oyu (8205 m) (Central Himalaya). See Figures 1, 2 (insert between p. 94&95), 5~7, 22~24. tables and figures. In addition to the large-scale proof-system based on the arrangement of the mappings and the recording of type localities, positions, so that they complete the glacioge- which do not only occur on the valley floors but morphologic map (Figures 1, 2(insert between p. partly also on remote slopes and mountain flanks, 94&95), 16). Especially the indicators of the past 34 geomorphologic profiles (Figure 2(insert glacier thickness can be inferred from these between p. 94&95), Figure 3: Pro. 1~34), mainly profiles. All indicators marked in the maps and valley cross-profiles distributed over the entire profiles have been documented on the spot by investigation area, have been recorded (Figures analogue photographs and photo-panoramas in a 5~7, 9~15, 17, 18, 22~24). These profiles are meant medium- sized format. to give an impression of the three-dimensional 94 Journal of Mountain Science Vol 3 No 2 (2006) Figure 2 Quaternary-geological and glacio-geomorphological map 1:140 000 of the Khumbu- and Khumbakarna Himal (Cho Oyu-, Mt.Everest- (Chogolungma- i.e., Sagarmatha-) and Makalu massifs) in the Central Himalaya.