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1.
天山乌鲁木齐河源1号冰川物质平衡过程研究   总被引:11,自引:10,他引:11  
天山乌鲁木齐河源1号冰川1958-1959~1991-1992年度,以负物质平衡状态为主,累积负平衡量达851.9×104m3,冰川平均亏损4562mm水层,与中亚山地冰川物质平衡的变化趋势相似,均是由夏季平均气温升高和年降水量减少引起的。分析17a的物质平衡实测资料表明,净物质平衡与平衡线高度,以及平衡线高度与夏季平均气温和年降水量存在着密切关系,夏季平均气温变化1℃,平衡线高度变化102m,年降水量变化100mm,平衡线高度波动58m。  相似文献   

2.
天山乌鲁木齐河源1号冰川新近出现大的物质负平衡   总被引:21,自引:9,他引:12  
郑本兴 《冰川冻土》2000,22(1):62-64
以天山乌鲁木齐河源1号冰川1996/1997年度和1997/1998年度实测物质平衡资料为基础。利用等直线法计算出1号冰川年物质平衡分别为-853.0mm和-780.9mm,相庆的AAR植分别为0.25和0.33自1959以来,1996/1997年度1号冰川物质负平衡值最大,1997/1998年度次之,根据该地区气温和降水记录资料分析,造成这 结果的主导因素是气温,尤其是夏季消融期气温,其次是降水  相似文献   

3.
王宁练  刘时银 《冰川冻土》1997,19(3):207-213
通过冰川波动历史来揭示气候变化是一种重要的方法。然而,以往有关这一方面的研究大都是一些定性的。文章试图依据冰种变化来定量的研究气候变化,并且通过近百年来天山乌鲁木齐河源1号冰川的变化,揭示出本世纪以来该河源地区夏季气温上升约0.23 ̄0.25℃,同时,对于该冰川不同长度规模时的气候敏感性也进行了讨论。  相似文献   

4.
根据乌鲁木齐河源区末次冰盛期形成的保存完好的古冰川遗迹和现代气候条件下冰川物质平衡与气候的关系,用冰川动力学方法估算出冰川达到末次冰盛期规模时的气候条件。依据末次冰盛期冰川面积,结合冰川平衡线高度和冰川体积综合分析,乌鲁木齐河源区末次冰盛期的夏季气温应比现代低4.8℃左右,降水约只有现代的30%。但目前其它古气候方法的研究结果表明,末次冰盛期的夏季气温比现代低5.6℃左右,两者相差0.8℃,其原因可能主要是冰川动力学方法未考虑构造抬升对气温的影响,据此推测,乌鲁木齐河源区末次冰盛期至今的构造上升量约为130m。  相似文献   

5.
天山乌鲁木齐河源1号冰川径流对气候变化的响应分析   总被引:10,自引:6,他引:4  
利用天山乌鲁木齐河源1号冰川1959-2006年的气象、冰川物质平衡和1980-2006年的水文资料,分析了其冰川径流的变化.结果表明:由于1996年以来的显著升温,导致了1号冰川水文点径流主要受夏季气温变化的控制,冰川物质损失对径流的补给作用已超过了降水的作用.1996-2006年与1980-1995年相比,夏季气温...  相似文献   

6.
山地冰川对气候变化的响应最为敏感, 在全球变暖的大背景下山地冰川和极地冰盖正在发生显著的变化。冰川运动速度的变化是气候变化的结果之一。乌鲁木齐河源1号冰川是中国西部山地冰川的代表, 本文以1981-2007年27a的运动速度资料与1982年以来的季节运动速度资料为基础, 结合冰川物质平衡、气温、降水等资料分析冰川运动速度对气候变化的响应。研究发现, 27a来1号冰川运动速度下降趋势明显, 冬、夏季节运动速度波动较大, 但夏季运动速度较大。气候变化通过冰川物质平衡的改变作用于冰川运动速度, 物质平衡的持续亏损最终导致了冰川运动速度的持续降低。夏季的高温与降水对冰川运动速度具有加速的作用。  相似文献   

7.
利用1946—2005年北极Svalbard、斯堪的纳维亚及挪威南部冰川物质平衡资料,分析了冰川物质平衡的变化特征及其对气候变化的响应.结果表明:北极Svalbard地区冰川物质平衡具有较低的年振幅和较小的年际变化;环北极的斯堪的纳维亚地区和挪威南部地区冰川物质平衡则具有较高的年振幅和较大的年际变化;20世纪80年代末90年代初,3个地区冰川物质平衡均达极大或较大值,之后呈加速向负平衡发展之势.冰川物质平衡对气候变化的敏感性与其物质平衡状态有关:物质平衡越是趋向正平衡发展的冰川,其敏感值较高,反之亦然;海洋性冰川较大陆性冰川对平衡线高度变化(气候变化)敏感.平均而言,三个地区冰川物质平衡在观测期内的亏损量相对于零平衡状态而言,相当于气温上升了0.32℃.冰川净物质平衡对1℃升温的敏感性变化范围为-0.42~-0.99mw.e..a-1,对10%降雪增量的敏感性为+0.01mw.e..a-1~+0.57mw.e..a-1;平衡1℃升温导致的冰川净物质平衡消融需要降雪量增加24%.冰川物质平衡对气候变化的敏感性与其所处气候环境背景(大陆度)相关性,越是趋向海洋性的冰川其敏感性越高.  相似文献   

8.
西北地区冰川径流变化的某些特征   总被引:23,自引:13,他引:10  
由于冰川的存在及其退缩,乌鲁木齐河源1号冰川的径流量高出同等条件下非冰川区径流量的61%,其中92%是由于冰川退缩和减薄补给的.70年代中期开始的气候变暖引起的冰川径流增加过程,在冰川补给最丰富的塔里木河流域年径流系列中有一定程度的反映,特别是在冰川覆盖率较大(>5%)的河流,1977~1989年与1956~1976年相比,在冰川补给最大的8月份,降水减少,气温升高,而山区径流明显增大;根据不同方法对冰川物质平衡的研究成果表明,若气温升高1℃,冰川径流的增加幅度不小于目前冰川径流的50%,也就是说冰川的存在可以在一定程度和时间内抵消或减弱气候变暖对西北干旱区水资源的不利影响  相似文献   

9.
基于地理信息系统的太阳直接辐射与冰川物质平衡的关系   总被引:4,自引:1,他引:3  
丁永建 《冰川冻土》1998,20(2):157-162
基于冰川微地形对冰川物质平衡重要影响的认识,在考虑朝向、坡度、地形遮蔽等因素的条件下,以地理信息系统为手段,对乌鲁木齐河源1号冰川冰面太阳可能直接辐射进行了理论计算.在此基础上,建立了计算冰面任意一点物质平衡的B=f(T,R)(气温-辐射)模型.比较了该模型与B=f(T)(气温)模型、B=f(P,T)(降水-气温)模型及B=f(Q)(能量平衡)模型之间的优缺点,表明该模型具有物理意义明确、计算精度较高、参数易于获得等优点,从而为计算冰川物质平衡提供了新的途径.  相似文献   

10.
从末次冰盛期冰川规模探讨当时的气候环境   总被引:4,自引:2,他引:4  
根据乌鲁木齐河源区末次冰盛期形成的保存完好的古冰川遗迹和现代气候条件下冰川特平衡与气候的关系。用冰川动力学方法估算出冰川达到末次冰盛期规模时的气候条件。依据末次冰盛期冰川面积,结合冰川平衡线高度和冰川体积综合分析,乌鲁木齐河源区末次冰盛期的夏季气温应比现代低4.8℃左右,降水约只有现代的30%,但目前其它古气候方法的研究结果表明,末次冰盛期的夏季气温比现代低5.6℃左右,两者相差0.8℃,其原因可  相似文献   

11.
The compilation of statistical data for 269 seismic crustal sections (total length: 81,000 km) which are available in the U.S.S.R. has shown that the preliminary conclusions drawn on relations between the elevation of the surface relief and Bouguer anomalies on one hand and crustal thickness (depth to the M-discontinuity) on the other hand are not fulfilled for the continental part of the U.S.S.R. The level of isostatic compensation has been found to be much deeper than the base of the earth's crust due to density inhomogeneities of the crust and upper mantle down to a depth of 150 km.

The results of seismic investigations have revealed a great diversity of relations between shallow geological and deep crustal structures:

Changes in the relief of the M-discontinuity have been found within the ancient platforms which are conformable with the Precambrian structures and which can exceed 20 km. In the North Caspian syneclise, extended areas devoid of the “granitic” layer have been discovered for the first time in continents. The crust was found to be thicker in the syneclises and anteclises of the Turanian EpiHercynian plate. In the West Siberian platforms these relations are reversed to a great extent.

Substantial differences in crustal structure and thickness were found in the crust of the Palaeo zoides and Mesozoides. Regions of substantial neotectonic activity in the Tien-Shan Palaeozoides do not greatly differ in crustal thickness if compared to the Kazakhstan Palaeozoides which were little active in Cenozoic time. The same is true for the South Siberian Palaeozoides.

The Alpides of the southern areas in the U.S.S.R. display a sharply differing surface relief and a strongly varying crustal structure. Mountains with roots (Greater Caucasus, Crimea) and without roots (Kopet-Dagh, Lesser Caucasus) were found there.

The Cenozoides of the Far East are characterized by a rugged topography of the M-discontinuity, a thinner crust and a less-pronounced “granitic” layer. A relatively small thickness of the crust was discovered in the Baikal rift zone.

The effective thickness of the magnetized domains of the crust as well as other calculations show that the temperature at the depth of the M-discontinuity (i.e., at depths of 40–50 km) is not higher than 300–400° C for most parts of the U.S.S.R.  相似文献   


12.
The deinocephalian pelvic girdle, of general pelycosaurian structure, is useful in systematic diagnosis. In primitive Russian deinocephalians, two contrasting pelvic patterns are recognized, one light, thin-walled, narrow, and of V-shaped cross-section, and the other massive, thick-walled, wide, and of U-shaped cross-section. The former is characteristic of two families of lightly- built, mobile land carnivores, the Eotitanosuchidae and the Brithopodidae. The Eotitanosuchidae are more primitive and pelycosaur-like, while the Brithopodidae show more variation, and specializations of large size, shallower acetabulum (related to mobility?), and re-enforcement of a weak pubic symphysis by additional processes. The massive type of pelvis characterizes large, heavily built herbivorous animals of the family Estemmenosuchidae. In general pelvic structure, the Estemmenosuchidae resemble the South African anteosaurs and tapinocephalians and the Russian tapinocephalians. In detail, however, they show a more primitive stage of evolution, overlaid by characteristic specializations which relate them more closely to the advanced Russian forms than to those of South Africa. Three new genera are erected, Biarmosaurus, fam. Eotitanosuchidae; Chthomaloporus, fam. Brithopodidae; and Molybdopygus, fam. Estemmenosuchidae. One specimen formerly referred to Deuterosaurus Yefremov 1954, and five formerly included in the type of Brithopus Yefremov 1954 are referred to Molybdopygus. The more primitive deinocephalians are from Yezhovo in the Ocher District, Perm Province, while more advanced forms are from Isheyevo, in Tataria, where-therocephalians and other South African elements are also found. It is therefore concluded that the Ochersk beds are older than those of Isheyevo and must be dated to zone I of Yefremov's system. — N. Hotton III.  相似文献   

13.
The recent experience of the rising cost of exploiting new material resources in the U.S.S.R. has led to exploration of alternative methods, particularly greater intensification of exploitation. The regional variations in the balance between intensive and extensive methods is considerable and is consequently an important aspect of Soviet geographical research. This paper discusses the criteria and methodology for this crucial economic/resource regionalization of the U.S.S.R.  相似文献   

14.
Soviet geologists consider the Precambrian to be divided into two groups — Archaean and Proterozoic; but such a division is unsatisfactory. A major unconformity separates Proterozoic volcanic and sedimentary formations from an underlying sequence that contains two supergroups of supercrustal formations. The oldest of these is unanimously considered to be Archaean. Rocks of that supergroup play an essential part in the composition of the Baltic, Ukrainian, Aldan and Anabar Shields and of the ancient fold belts of the East-European and Siberian platforms.Distinctive features in the composition, tectonic structure, metamorphism and metallogeny of Archaean complexes lead to the conclusion that they were formed in specifically mobile areas, different from geosynclinal areas.The other supergroup of high-grade metamorphic rocks has no clear place in the accepted two-fold stratigraphic scheme of the Precambrian, and it is considered sometimes to be Archaean and sometimes to be Early Proterozoic. We propose restoring the forgotten name “Eozoic” for that supergroup. Eozoic complexes are characterized by peculiarities of composition and inner structure, which signify changes in the tectonic regime of the earth at the lower and upper boundaries of the Eozoic Supergroup. These peculiarities give grounds for distinguishing the Eozoic Supergroup as an independent stratigraphic division.The Stanovoy Complex of the southern part of the Aldan Shield is a stratotype for the Eozoic Supergroup. Many well-known stratigraphic subdivisions of the Siberian Platform (e.g., the Eniseiskaya, the Birusinskaya series and others), the Taratash Complex of the Urals, the Goranskaya and Shahdarinskaya series of the South-West Pamir, the Tikitch complex and Aulskaya series of the Ukrainian Shield, and in part the Belomorsky Complex of the Baltic Shield, as well as some others, are also Eozoic.The Eozoic complexes are characterized by the following specific features: only some supercrustal formations are typical for them; the small number of rock types which have a total thickness about 5–6 km; relatively monotonous mineral composition of the rocks; variable quantitative ratios of rocks; absence of contrasting marker beds; regional metamorphism and ultrametamorphism in the amphibolite facies; wide development of ultrametamorphic granitoids and migmatites; distinct tectonic differentiations of the basin of sedimentation.Dates determined by isotopic analyses, which mostly reflect the metamorphism of the deposits, fall predominantly in the range 2600–3100 Ma.  相似文献   

15.
A list of all Upper Cretaceous sea-lilies known from the U.S.S.R. is given. Their stratigraphic and geographic distributions are discussed. Three paleogeographic subprovinces, the south-eastern, the northern and the south-western, can be distinguished in the Mediterranean paleobiogeographic province of the U.S.S.R. based on the development and distribution of the Upper Cretaceous crinoids.  相似文献   

16.
A very interesting and informative paper on widespread occurrence of a thermal hydrosphere. Geothermal power uses are discussed. Distribution of heated waters, some up to 150° C is discussed in considerable detail, especially with reference to possible power utilization of the geothermal energy. Seven hydrothermal regions of the U.S.S.R. are discussed and delineated. Chemical quality of waters is referred to. There is a summary listing of locations in the U.S.S.R. where thermal waters could be utilized for generation of electric power. — B. N. Cooper.  相似文献   

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18.
A major field of research since the 1920s has been methods and theories of economic regionalization. The territorial-production complex is now recognized as a key developmental tool within the framework of economic-planning regions. Recently, there has been a more marked growth of study into problems of natural-resource development, social progress and change in the U.S.S.R. as well as into the spatial structure of other nations, particularly other socialist countries and non-socialist developing countries.  相似文献   

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