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    Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Sun Honglie
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    Since the founding of the People's Republic of China, the state has organized scientific survey of the Qinghai-Xizang Plateau several times and abundant results have been achieved. This work possesses profound impact in the world. However, because the emphasis of the survey in the past was placed primarily on the southern and southeastern parts of the Plateau, the study of its northwestern part is relatively l;ss.In the 1970s, a new survey program started and the whole program was divided into three stages. In the first stage (1973-1980), the Ximao autonomous region- was explored. In the second stage (1981-1986), Western Sichuan province, eastern Tibet, and the Hengduan Mts. in northwestern Yunnan province were explored. In the third stage (begun in 1987), the survey was made in the Karakoram and Kunlun Mts. area. The research in this stage is planned to complete within five years. We have already gained abundant firsthand data. At present, there are still many analyses, appraisals, and experiments awaiting to be done and appropriate summingups of the research works should be deepened as well.Up to now, the new advances gained in the study of the Qinghai- Xizang Plateau include the following respects:1. The geological features and regional evolution of the Plateau2. The upheavals of the Plateau since Late Cenozoic Era3. The characteristics and regionalization of the flora4. The structural types of altitudinal natural belts and the regularity of regional differentiationIn order to promote academic intercourse, the Editorial board of the Journal of Natural Resources and the Qinghai-Xizang Plateau Integrated Scientific Survey Team corporately compile this special issue, publishing the research results of the present stage. It is hoped that this will further the basic study of the natural environment and resources of the region.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Pan Yusheng
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    Through many explorations, the structural framework of the Qinghai-Xizang Plateau has been basically established, but the regionalization of the structures of the Karakoram and Kunlun Mts. region in the northwestern part of the Plateau is still not clear. In the recenr exploration, large amount of new data were obtained. It has been found that the Kude-Subashi structural zone is an independent important structural line of an earlier stage. It has also discovered that the Maza-Kangxiwar-Motzetage structural zone is connected with the Kunlua-shankou-Maqin structural zone. The above mentioned two structural zones c'ivided the Karakoram and Kunlun Mts. region into three belts, namely, north belt, middle belt, and south belt. The south belt, according to its developmental history, is linked to the Bayan Kara region and does not belong to the real Kunlun structure region.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Deng Wanming
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    The preliminary exploratory results about the basic-ultrabasic rocks of the Karakoram and western Kunlun Mts. are reported in this paper. The Kudi ultramafic rock bodies belong to the Alpine-type associations in general, but there are some differences between the Kudi bodies and the typical ophiolitic metamorphic peridotites in petrochemistry. At present, there is insufficient evidence to make a full interpretation of the formation of these bodies. The Middle Proterozoic metamorphic volcanics in Akazi section may have originated in a strongly attenuated continental lithosphere. According to the discriminations of the rare element and REE geochemistry the Upper Proterozoic metamorphic mafic lavas in Yixikgou section probably are formed at a Mid-ocean ridge and present truce oceanic lithosphere. Late Paleozoic volcanics may have erupted in a continental margin area. Relative strong continental volcanic activity existed in Cenozoicera, in which especially the Quaternary continental floor volcanics may be related to the rapid uplifting of the Qinghai-X izang plateau. The occurrences, petrological and geochemical characteristics and erupting stages of the volcanics found in southern Kunlun Mts. have been discussed in detail in the paper.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Wang Dongan, Chen Ruijun
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    A set of variegared volcaniclastic rocks outcropping in Yixiekegou on the northwest of Rude, Xinjiang, is underlied by the middle proterozic basic lavas. All the clastic fragments which constitute the volcaniclastic rocks are derived from the underlying volcanic rocks, so the mineral associations and chemical components of the volcaniclastic rocks are perfectly consistent with those of the underlying volcanic rocks. Obviously they have common characters, implying that they are closely related in origin.By comparing their chemical components, i: is found that the ophiblitic sedimentary rocks are different not only from the normal greywacke but also from the developing island arc oasalt. But there are obvious similarites between the volcaniclastic rocks and the oceanic tholeiite. This shows the sedimentary rocks possess the ophiplidc characters.The various parameters (XM, D, C, M, G) of the grain size analyses reveal that the rhythmic sedimentary cycling of the rocks is clear, the sorting of most samples is comparatively good, but the hydrodynamic is from weaker to weak. The Suhu's distinguishing parameters (<9.84) stand for that this set of sedimentary rocks are products of gravity flow in the range of deep sea fan (turbidite fan).In summary, we can determine that it was deposited in oceanic deep-water (far from the continent).
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Zhang Yuquan, Xie Yingwen
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    This paper deals with the Rb-Sr biotite isochron ages of the granitoid in the Sanshiliying-fang area of the Karakoram and Kunlun Mts. region. It has peen found that the Rb-Sr biotite isochron age of the diorite is 539 Ma, belonging to the Cambrian period, and that the Rb-Sr biotite isochron age of the Saidulla granodiorite is 215 Ma, being equivalently of the late Trias-sic period. The results also show that there exists the granitoid of Early Paleozoic Era in the Gonggol-Akagazi petrographical belt.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Shu Peiyi, Liang Shanghong, Zhang Liming
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    The observed .data used in this paper .are five deep and teleseismic P waveforms recorded by short period seismograph at the Hetian seismic station. Based on comparing the synthetic ones waveforms with the observed, the deep crust structure of the southwestern edge of the Tarim basin and of the. northern part of the Kunlun mountains is discussed. Results show that beneath about 30 km are higher velocity layer. The crustal depth is about 53 km. Since the transmission seismic beams came from different directions, the calculation indicates small differences of velocity structure and lateral variance.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Zhang Qingsong, Li Bingyuan
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    It can be confirmed that intensive uplifting of the Karakoram and West Kunlun Mountains occurred in the period from Late Pliocene epoch to Early Pleistocene, 'This is proved by the differences of Pliocene (Atushi formation) and Early pleistocene (Xiyue Conglomerate formation) stratigraphic features. Both in the interior of the Karakoram and West Kunlun Mts. and on thejnorthern side of the Kunlun Ms., the Atushi formation mainly composed of silts and fine sands is uniform. It means that the upheaval between the Kunlun Mts. and the Tarim Basin was gentle in Pliocene age. But the Xiyue Conglomeration, as a typical Ma-lasse deposit, is characterized by layered boulder conglomerates and coarse sands. It testifies that a great upheaval on the northern side of the Kunlun Mts. occurred in early Pleistocene age due to intensive uplifting. The climate was warm and humid during Pliocene age.A regional tectonic movement occurred between Early and Middle Pleistocene ages. This is proved by a series of folding, faulting and unconformity following the upheaval of the Plateau. Middle Pleistocene moraines have been found on of high peaks, That is the first gla-ciation on the Karakoram and west kunlun Mts. Two glaciations occurred in Pleistocene ape. The size of glaciation is less in the latter stage than in the former stage.Drying tendency .was progressing rapid ly since Late Pleistocene age. Levels of Plite;iu lakes were droping rapidly. The ancient lake of Tianshuihai was disintegrated and withered. Bangong Lake and other lakes changed from exterior drainage to interior drainage. Glaciers retreated. The vegetation changed from semi-desert throur stepps to desert. Loss on the northern slope of the Kunlun Mts. was formed at the same time.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Su Zhen, Liu Shiyin, Wang Zhichao
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    There are 446 modern glaciers on Mt. Muztagata and Mt. Kongur and the total area is about 898.08 km2. Ice caps, Turkistan valley glaciers, and canyon-valley glaciers are the main and special types in this area. The altitudes of snowlines are generally between 4800 and 5200 m. above sea level. The estimated annual temperature there ranges from - 10℃ to - 14℃ and the precipitation from 477 to 679 mm.Because of the effects of continental climate, the modern glaciers possess the characteristics of the glacier of continental type. These are shown in the physical features such as ice formation, the temperature of ice layers, glacial movement and ablation, etc.As for the variation of advance or retreat of glaciers in recent years, the glaciers have been retreating since the mid-19th century. In the mid-70s of this century, most of them were in a stable state, some advanced, and only a few of them still retreated. In the period of investigation in 1987, it was found that most of them turned to be retreating with a small magnitude, a few still remainded in a stable state, and several advanced.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Huang Cixuan, Zhang Qingsong, Liu Futao
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    The Bangongcuo Lake is situated in westera xizang at 33°40' N and 79°E approximately. The lacustrine deposit profile studied lies 30 km to the east of the Bangongcuo Lake. On the basis of the results of pollen analysis and C14 dating, the author have discussed the paleovege-tation and the paleoclimate in the later period of Late Pleistocene in the ancient lake basin. During the period 40000-24000 years B. P., the changes of pleovegetation underwent a process from semi-desert to steppe and then to desert successively. Plant here include Artemisia, Chenopodiaceae, and Ephedra. In the mountain; nesr the lake, there were a few arbors, such as Pinaceae and Betulaceae. The paleoclimate was wetter and warmer than it is at present. During the period 36000-28000 years B. P° the humidity and the temperature were relatively high. This paper has also discussed the changes of physical environment in relation to the uplift of the plateau since the later period of Late Pleistocene.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Zheng Du, Zhang Baipin
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    The Karakoram and West Kunlun Mountains in the northwestern part of the Qinghai-Xizang Plateau are a transitional area between the alpine desert and the montane desert.On the bases of recent observations and investigations the structure type of the altitudinal belts, the regional differentiation, and environmental problems in the study area are dealt with in this paper.Characterized by the continental arid type of climate, the altitudinal belts of the Karakoram and West Kunlun Mts. consist chiefly of varions desert and steppe belts. According to the combination pattern of the altitudinal belts, the following four structure-type groups and seven structure types of the altitudinal belts may be identified in the study area:Ⅰ. The arid structure-type group. This structure-type group inclludes three structure types as follows: (1) the xero-mesophilic pattern consisting of the montane forest-steppe belt and the alpine meadow belt; (2) the meso-xerophilic pattern consisting of the montane steppe belt and the alpine meadow belt and (3) the xerophilic pattern possessing the montane steppe belt only.Ⅱ. The extremely arid structure-type group. It includes one structure type. That is the super-xerophilic pattern consisting of the following altitudinal belts: the montane desert belt, the alpine desert belt, the subnival pelt and the nival belt.Ⅲ. The alpine arid structure-type group. It includes two structure types as follows: (1) the super f rigo-xerophilic pattern consisting of the alpine desert belt, the subnival belt, and the nival belt; and (2) the frigo-xerophilic pattern consisting of the alpine desert steppe belt and the alpine desert belt.Ⅳ. The alpine semi-arid structure-type group. It includes one structure type. That is the frigo-meso-xerophilic pattern consisting of the following altitudinal belts: the alpine steppe belt the alpine meadow belt, the subnival belt, and the nival belt.Corresponding to the areal differentiation of the physical geography of the region, the above mentioned four structure-type groups and seven combination patterns of the altitudinal belts vary obviously with the flanks of the Karakoram and West Kunlun Mts. Tte combination of the altitudinal belts and the elevation of each altitudinal belt on the western section are different to a considerable degree from those on the eastern section. The moisture-bearing air masses coming from the west play a significant role in the regional differentiation of the altitudinal belts. They make the desiccation of the southeast more severe than that of the northwest. The broad valleys, basins and plateaus between the Karakorum and the Kunlun Mts. are climatically extremely arid. In these areas the montane desert and the alpine desert are dominant.Owing to the important function of the montane forests in water retention and soil conservation in the arid region, the overlogging and misuse of the forests should be replaced by rational utilization and regeneration. It is suggested that the local government should select proper areas where growing the montane coniferoue forests occur in the West Kunlun Wts. as nature reserves so as to protect a number of endemic and rare species of plants. It is also necessary to establish nature reserves for the conservation of the natural landscape and the wildlife of the Qiangtang Plateau.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Gu Guoan, Zhang Leide
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    The West Kunlun Mountains are located in the northwestern part of the Qinghai-Xizang Plateau with complex topographic and climatic conditions, high peaks and deep valleys. All these make the spectra of vertical soil zones very complicated. The spectra can be divided into five categories: super-arid, arid, semiarid, frigid arid, frigid semiarid. In the semiarid spectrum on the Kunlun Muntain range, there is only spruce. In the arid and semiarid spectra in the southern part of the Tarim basin, there are widely distributed meadow grassland and grassland.Significant difference in spectra has been found between the marginal mountains and the interior mountains and between the low hills and the plateau surface above 5,000 meters
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Zhang Leide, Gu Guoan
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    The mountain areas in the Kezilesu, Kashi, and Hotan regions of Xinjiang which belong to the West Kunlun Mountains occupy 90 percent, 57 percent, and 42 percent of their respective total areas. The surroundings are very gool for developing animal husbandry. The rational utilization according to the natural ecolJgical conditions of the different vertical zones of the mountains can give full play to the productive effect of land resources.At present, the land use in the valleys is most intensive. Thereafter, unified planning of the mountains is important for preventing land, from deterioration due to overgrazing. The distribution of loess of the Kunlun Mountains has obvious relations to the attributes of the land resources and productivity.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Li Bosheng
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    The Maimacuo nature reserve is situated in the northwestern part of the Qiangtang Plateau in Tibet, extending from 80°40' to 83°30'E and from 33°30' to 34°40'N with an area of about 25 thousand km2. In administrative division the reserve is part of both Ritu county and Gaize county.The basic character of the topography in the reserve is that the high mountain alternates wi h the lake basin. The climate is cold and dry. The annual temperature approximates to0℃——1℃, and the mean temperature is - l4℃ in the coldest month (January) and 10℃ inthe warmest month (July). The frost-free period lasts from 20 to 40 days every year and the annual pricitation is 150-200 mm.The basic vegetation type is the high-cold steppe. The plants grow well and have 6 main formations as follows. Form. Stipa purpurea, Form. Stipa subsessififlora var. basiplumosa, Form, Carcx moorcroftii, Form. Artemisia nanschanica, Form. Artemisia strackeyi, and Form. Oxy-tropis microphylla.The reserve is rich in wild animals. There are rare or nearly extinct wild animals among them, such as Poephagus mutus, Pantnolops hodgsoni, Asinus kiang, Ovis ammon, Pan-thera uncia, etc. These wild animals are seldom seen in Tibet.Seeing that the primeval high-cold steppe ecosystem remains in this region and has important scientific value, the author suggests that the Maimacuo nature reserve be protected as, the representative ecosystem of Tibet.