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1.
Austre Lovénbreen冰川和Pedersenbreen冰川是位于北极斯瓦尔巴群岛的两条典型的多温山谷冰川,中国北极黄河站冰川考察组于2009年在两条冰川上开展了密集的GPS/GPR测量工作。基于现场实测数据,结合冰川槽谷数值研究的幂函数模型,本文解算了Austre Lovénbreen冰川和Pedersenbreen冰川的模型参数,根据两条冰川不同断面模型参数的变化规律,确定冰川槽谷发育的形态特征;分析冰川侵蚀在槽谷发育过程中的作用,比较两冰川地形和冰流速差异对冰川槽谷发育的影响,探究冰川槽谷形态发育状态与冰流速的关系。结果表明Pedersenbreen冰川槽谷发育优于Austre Lovénbreen冰川,两条冰川槽谷地形更接近于V型而非U型。尽管两条冰川相邻,当前的发育状态却呈现出明显的差异, Pedersenbreen冰川流速较快,冰川侵蚀过程以侧蚀作用为主; Austre Lovénbreen冰川流速较慢,冰川侵蚀过程以下蚀作用为主;这主要是由于两条冰川所处的山谷地形不一致造成的。  相似文献   

2.
贡嘎山是青藏高原东部大雪山脉的主峰,也是青藏高原东部的最高峰,海拔7 756 m,位于四川省康定县和泸定县之间。由于其海拔高,降水充沛,海洋性冰川发育。以贡嘎山为中心,发育有74条现代冰川,冰川面积达255.1 km2,其中海螺沟冰川最为著名。  相似文献   

3.
近年来,随着绝对年代的不断增加,第四纪冰川作用的启动时间以及演化特点日益明确,为探讨中纬度地区的冰川的形成机制提供了重要依据,同时也为研究中国第四纪冰川发育的构造与气候耦合关系奠定了重要基础。亚洲中纬度地区山地第四纪冰川的冰进时序、冰期历史和冰川规模显示出不同特点。总体来说,西部山地的冰川规模随时间逐渐缩小,冰川历史较为完整,冰川规模大于亚洲东部,东部山地的冰期历史较短,冰川作用的阶段性明显;不同地区的最大冰川扩展规模在时间上不一致,尤其是在末次冰期旋回中,MIS3/4阶段的冰川规模大于传统意义上的末次冰盛期(LGM),冰进时序和规模演化指示了不同的大气环流尤其是西风环流和季风环流对冰川发育的重要影响。此外,构造因素深刻影响着不同地区的冰期系列。  相似文献   

4.
玉龙雪山冰川稳定同位素分馏冬夏对比   总被引:8,自引:0,他引:8  
利用玉龙雪山白水1号冰川区冬季和夏季表面积雪、雪坑、融水以及白水河河水中δ18O资料,对比分析了冬季和夏季我国典型季风温冰川系统内稳定同位素分馏行为的差异。分析结果表明,夏季冰川系统内各水体相变过程中稳定同位素分馏程度均比冬季强烈,指示出夏季季风海洋型冰川强烈消融的特点。另外,不论是冬季还是夏季,从表面积雪到融水再到由融水补给的河流,δ18O垂直变化梯度依次增大,反映了从固态降雪向冰川融水补给的河流河水转换过程中,稳定同位素分馏程度逐渐增强,体现了沉积后过程对海洋型冰川区同位素记录的影响具有空间差异性。  相似文献   

5.
新疆哈密八大石森林上限树轮记录的温度变化信息   总被引:1,自引:0,他引:1  
本研究采集新疆哈密地区八大石西伯利亚落叶松森林上限树芯样本,建立标准宽度年表.通过树木年轮-气候响应分析,发现标准年表序列反映了该地生长季(5~9月)的月平均温度及月平均最低温度信息,且该序列与前人的研究结果对比具有较好的一致性.树轮宽度序列主要反映出了1885年之前以冷期为主,1885年之后以暖期为主,且暖期延续时间变长,20世纪后半期增温的趋势.该序列与天山冰川进退的时间较为一致,同时也发现该序列极值与当地蝗灾具有很好的对应,与亚洲近两百年来的大型火山喷发事件具有很好的一致性,由此可以推测该年表在一定程度上捕捉到了冰川进退、火山事件的环境信息.  相似文献   

6.
关于南国冰臼群成因的商榷之二   总被引:7,自引:1,他引:7  
韩同林  劳雄  郭克毅 《热带地理》2001,21(2):189-194,F003
南国冰臼群分布区大量冰川堆积、冰川条痕石及变形砾石的发现,再次有力地证明是“冰臼”不是“壶穴”的正确结论,由冰川漂砾经融冻作用形成的“石海”,与化学风化作用产生的花岗岩“石蛋”地貌特征,有天渊之别,不应混为一谈;边滩是由河流冲积物组成,不能与基岩冰床相提并论;圆滚水钻与急流旋涡及风蚀作用,形成的动力学性质、方向和方式完全不同,不该阴错阳差;节理、构造只影响冰臼的形态和发育程度,不是控制形成的动力学性质、方向和方式完全不同,不该阴错阳差;节理、构造只影响冰臼的形态和发育程度,不是控制冰臼的发育部位,不致于是非不辨,南国地区古冰川遗迹的大量发现,证明距今约二三百万年的第四纪早期确实曾发生过大规模的古冰川运动,为争论了半个多世纪的中国东部中低山区有无第四纪冰川问题,从此画上一个圆满的句号。  相似文献   

7.
位于横断山区的梅里雪山地区,受地形与气候的影响,该地区光学遥感及微波遥感应用较为受限。论文基于大疆精灵4RTK无人机搭配中海达UBase,于2018年11月9日和2019年11月12日对梅里雪山地区明永冰川末端开展了2期摄影测量,估算冰川消融区表面高程变化,监测冰川动态变化。研究结果表明:冰川区表面形态在不同位置有显著差别,航测冰川区中下部大量表碛覆盖,有少量沿冰川主流线方向发育的裂隙;航测冰川区中上部表碛覆盖较少,大量横向裂隙发育。2018年11月至2019年11月,明永冰川末端表面高程平均变化-1.67 m。冰川表面高程变化空间分布差异显著,在航测冰川区上部高程差存在正负交替现象,航测冰川区中部以减薄为主,而航测冰川区下部以增厚为主。与高亚洲地区其他山系冰川变化对比,梅里雪山地区是冰川表面高程变化最显著的地区。  相似文献   

8.
叶玮 《干旱区地理》1991,14(3):79-85
阿尔泰山砂金资源丰富,类型多样,按其成因可分为残积砂金矿、冲积砂金矿、洪积砂金矿、冰川-冰水砂金矿、风积砂金矿和复合型砂金矿六大类。不同类型砂金矿形成环境不同,砂金成矿规律也不一样.受成矿条件影响,阿尔泰山砂金矿的分布以垂直分带性为其主要特点.高山带砂金矿以冰川-冰水型为主;中山带冲积砂金矿最为发育;低山丘陵区集中分布残、洪积砂金矿;山前平原则发育风、洪积砂金矿。  相似文献   

9.
天山东部冰芯pH值和电导率的大气环境空间差异   总被引:2,自引:1,他引:1  
冰芯电导率是大气环境变化的替代性指标.对我国天山东部三个研究点奎屯哈希勒根48号冰川、乌鲁木齐河源1号冰川以及哈密庙儿沟平顶冰川粒雪芯中pH值和电导率的近期环境记录进行了分析研究.结果显示,三个研究点粒雪芯反映的近期pH值和电导率变化趋势不同:奎屯电导率随冰芯深度增加表现出升高趋势,哈密庙尔沟平顶冰川和乌鲁木齐河源1号冰川随冰芯深度增加表现出一定下降趋势;冰芯电导率平均值在哈密庙儿沟冰川最大,而其他两个点相对较小,这与矿物粉尘浓度和离子浓度的分布一致;雪冰电导率与粉尘及离子相关性分析表明,电导率主要受中亚粉尘活动影响,同时与Ca2+、Mg2+、Na+等相关性很高.通过比较显示,天山东部与我国西部其他研究点以及极地雪冰电导率的差异可以很好地反映大气环境的空间差异.  相似文献   

10.
张威  刘锐  刘亮 《地理科学进展》2015,34(7):871-882
东亚季风气候控制下的山地与岛屿冰期历史、冰川规模及其分布规律对深入探讨中国第四纪冰川的发生机制以及全球变化具有重要的科学意义。最新的绝对年代结果显示,中国东部及东亚沿海岛屿山地(包括中国台湾岛,日本本州岛、北海道,朝鲜盖马高原,俄罗斯远东山地等)的冰期启动与消亡时间存在显著差异,但均严格控制在末次冰期范围之内,相当于深海氧同位素阶段(MIS)4至2,冰川的发育规模在末次冰期早中期(MIS3/4)大于末次冰盛期(MIS2)。对研究区各山地和岛屿末次冰期冰川发育的基本特点进行比较后,明确了影响东亚季风影响区冰川作用的主要控制性因素有:气候因素、构造因素、纬度因素和海陆位置等,它们控制着末次冰期冰川的发生、分布与期次。在此控制性因素影响下,东亚低海拔山地不会出现比末次冰期更早的冰川作用。  相似文献   

11.
One of the most glacierized areas in the European Alps, the Mont Blanc massif, illustrates how fast changes affect the cryosphere and the related morphodynamics in high mountain environments, especially since the termination of the Little Ice Age. Contrasts between the north‐west side, gentle and heavily glaciated, and the south‐east side, steep and rocky, and between local faces with varying slope angle and aspect highlight the suitability of the study site for scientific investigations. Glacier shrinkage is pronounced at low elevation but weaker than in other Alpine massifs, and supraglacial debris covers have developed over most of the glaciers, often starting in the nineteenth century. Lowering of glacier surface also affects areas of the accumulation zone. While modern glaciology has been carried out in the massif for several decades, study of the permafrost has been under development for only a few years, especially in the rock walls. Many hazards are related to glacier dynamics. Outburst flood from englacial pockets, ice avalanche from warm‐based and cold‐based glaciers, and rock slope failure due to debuttressing are generally increasing with the current decrease or even the vanishing of glaciers. Permafrost degradation is likely involved in rockfall and rock avalanche, contributing to the chains of processes resulting from the high relief of the massif. The resulting hazards could increasingly endanger population and activities of the valleys surrounding the Mont Blanc massif.  相似文献   

12.
Glaciers are the most important fresh-water resources in arid and semi-arid regions of western China. According to the Second Chinese Glacier Inventory (SCGI), primarily compiled from Landsat TM/ETM+ images, the Qilian Mountains had 2684 glaciers covering an area of 1597.81±70.30 km2 and an ice volume of ~84.48 km3 from 2005 to 2010. While most glaciers are small (85.66% are <1.0 km2), some larger ones (12.74% in the range 1.0–5.0 km2) cover 42.44% of the total glacier area. The Laohugou Glacier No.12 (20.42 km2) located on the north slope of the Daxue Range is the only glacier >20 km2 in the Qilian Mountains. Median glacier elevation was 4972.7 m and gradually increased from east to west. Glaciers in the Qilian Mountains are distributed in Gansu and Qinghai provinces, which have 1492 glaciers (760.96 km2) and 1192 glaciers (836.85 km2), respectively. The Shule River basin contains the most glaciers in both area and volume. However, the Heihe River, the second largest inland river in China, has the minimum average glacier area. A comparison of glaciers from the SCGI and revised glacier inventory based on topographic maps and aerial photos taken from 1956 to 1983 indicate that all glaciers have receded, which is consistent with other mountain and plateau areas in western China. In the past half-century, the area and volume of glaciers decreased by 420.81 km2 (–20.88%) and 21.63 km3 (–20.26%), respectively. Glaciers with areas <1.0 km2 decreased the most in number and area recession. Due to glacier shrinkage, glaciers below 4000 m completely disappeared. Glacier changes in the Qilian Mountains presented a clear longitudinal zonality, i.e., the glaciers rapidly shrank in the east but slowly in the central-west. The primary cause of glacier recession was warming temperatures, which was slightly mitigated with increased precipitation.  相似文献   

13.
1970-2016年冈底斯山冰川变化   总被引:2,自引:0,他引:2  
基于修订后的中国两次冰川编目数据及2015-2016年Landsat OLI遥感影像,对冈底斯山1970-2016年的冰川时空变化特征进行分析,并利用相应时段的气温和降水数据,对冰川变化原因进行探讨,为全面认识冈底斯山在气候变暖背景下冰川的响应规律及区域水资源合理利用提供科学依据。结果表明:① 2015-2016年冈底斯山共有冰川3953条,面积1306.45 km 2,冰储量约58.16 km 3;冰川数量以面积< 0.5 km 2的冰川为主,面积则以介于0.1~5 km 2的冰川为主。② 1970-2016年冈底斯山冰川面积共减少854.05 km 2(-39.53%),冰川面积变化相对速率高达-1.09%/a,消融期气温升高是导致该山区冰川退缩的最主要原因。与中国西部其他山系冰川变化相比,冈底斯山是冰川退缩最为强烈的地区,且近年来冰川退缩呈加快趋势。③ 冈底斯山冰川面积减少主要集中在海拔5600~6100 m之间,海拔6500 m以上区域基本没有变化。除南朝向和东南朝向外,冈底斯山其他朝向冰川数量和面积均呈减少趋势,其中北朝向冰川面积减少最多,西北朝向冰川面积变化最快。④ 冈底斯山冰川面积变化自西向东呈加快趋势,其中东段冰川面积变化相对速率高达-1.72%/a,中段次之(-1.67%/a),西段仅为-0.83%/a。  相似文献   

14.
本文从天山冰川数量,冰储量、类型以及分布特征等方面系统地分析了天山冰川的资源及其分布规律,为经济建设提供可靠的山地水资源论据。  相似文献   

15.
Frich, Povl and Brandt, Erik: Holocene talus accumulation rates,—and their influence on rock glacier growth. A case study from Igpik, Disko—West Greenland. Geografisk Tidsskrift 85: 32–44 Copenhagen, October 1985.

The Igpik area is located ten km east of Godhavn on the south-coast of the island Disko. Geologically the area is dominated by Tertiary basalt formations.

A general geomorphological classification of this area, which covers approximately three square kms, has been made. Based on radiocarbon ages of former marine levels in the Disko Bugt area, the beginning of talus accumulation has been determined for two talus cones situated on raised beaches. They have ages of 5800 and 7900 14C y. B.P. Using theodolite readings, the volumes of three different talus cones have been determined and two average talus accumulation rates have been calculated for the cones located on raised beaches. These values are transformed into an average Holocene rockwall retreat rate of 0.0005 and 0.0015 m/year, respectively. The total volume of two lobate rock glaciers is calculated to be 2.2 mill, cu.m and as they are located inside 9000 years old local moraines, the average Holocene mass-transfer through the third talus cone has been estimated to 1.4 106 tons×m/sq.km/y. Finally the results are discussed, with reference to other areas, and as a possible threshhold for the initiation of rock glaciers.  相似文献   

16.
This paper recognizes the contribution of Professor Wilfried Haeberli for his inspiration and leadership in the field of permafrost science and his generous encouragement, both direct and indirect, to the ETH Researchers who have, through him, endeavoured to contribute to this fascinating research area. The multidisciplinary investigations described in this paper have focused on three rock glaciers, Muragl, Murtèl‐Corvatsch and Furggwanghorn, all of which have been subject to a varying degree of prior study, and which are continuing to attract new generations of researchers to understand and explain the processes and predict future behaviour. This paper marks a stage at which it is possible to summarize some advances in the state of the art and associated innovations that can be attributed to early motivation by Wilfried Haeberli and offers a tribute as well as gratitude for his ongoing feedback and advice. Some thoughts on the development of thermokarst due to water ponding and flow, and a conceptual model of geotechnical mechanisms that aim to explain some aspects of rock glacier kinematics, are also introduced.  相似文献   

17.
塔里木盆地南缘古绿洲分布与河流、冰川的关系   总被引:1,自引:0,他引:1  
依据野外实地考察和考古资料对塔里木盆地南缘河流与其流域内的古绿洲分布情况进行了研究,着重探讨了历史时期以来古绿洲分布规律、迁移过程与河流、冰川特点之间的耦合关系。研究表明,盆地南缘东侧的且末、若羌地区河流及冰川规模小,数量少;其中下游形成的绿洲小,且从汉代至今都在河流出山口处分布,变化不大,而西侧的和田地区反之,河流下游的沙漠中分布着数量较多的大规模古绿洲;汉代的古绿洲多分布在冲积平原下部的沙漠中心,中部则是以唐代古绿洲遗址为主,上部沙漠边缘多为近代和现代绿洲;古绿洲迁移最大距离可达200 km左右;河流年径流量与古绿洲在沙漠分布的距离呈正相关关系。  相似文献   

18.
廖海军  刘巧  钟妍  鲁旭阳 《地理学报》2021,76(11):2647-2659
表碛覆盖型冰川是中国西部较为常见的冰川类型。表碛层存在于大气—冰川冰界面,强烈影响大气圈与冰冻圈之间的热交换。表碛厚度的空间异质性可极大地改变冰川的消融率和物质平衡过程,进而影响冰川径流过程和下游水资源。基于Landsat TM/TIRS数据,运用能量平衡方程反演了贡嘎山地区冰川表碛厚度,研究了贡嘎山地区冰川在1990—2019年间表碛覆盖范围及厚度变化情况,同时对比了东西坡差异。结果表明:① 贡嘎山地区冰川表碛扩张总面积达43.824 km2。其中,海螺沟冰川扩张2.606 km2、磨子沟冰川1.959 km2、燕子沟冰川1.243 km2、大贡巴冰川0.896 km2、小贡巴冰川0.509 km2、南门关沟冰川2.264 km2,年均扩张率分别为3.2%、11.1%、1.5%、0.9%、1.0%和6.5%;② 海螺沟冰川、磨子沟冰川、燕子沟冰川、大贡巴冰川、小贡巴冰川、南门关沟冰川表碛平均增厚分别为5.2 cm、3.1 cm、3.7 cm、6.8 cm、7.3 cm和13.1 cm;③ 西坡冰川表碛覆盖度高,表碛覆盖年均扩张率低,冰川末端退缩量小;东坡冰川表碛覆盖年均扩张率高,但表碛覆盖度总体低于西坡,冰川末端退缩量大。  相似文献   

19.
This paper presents a simple analytical model for estimating rock glacier age by coupling the ratio of frontal advance to total rock glacier length and the ratio of debris volume in the rock glacier to present debris flux in the talus cone–rock glacier transition zone. The model was applied to two rock glaciers at Prins Karls Forland, Svalbard. By assuming volumetric debris contents in the deforming layer of the rock glacier of between 0.3 and 0.4, we obtained age estimates for the rock glaciers of between 12 ka and 24 ka. The corresponding average rockwall retreat rates are between 0.30 and 0.62 mm a‐1. Considering the limitations of the model, we suggest a minimum age of 13 ka for the initiation of rock glacier development. Using this age, rockwall retreat rates for the seven rock glaciers investigated at Prins Karls Forland are between 0.13 and 0.64 m ka‐1 (assuming the volumetric debris content for the whole rock glacier/talus cone is 0.35). The model requires further testing on other datasets, better field estimates of the debris content and depth of the deforming layer, and could also benefit from the inclusion of an unsteady debris supply function in order to refine age estimates.  相似文献   

20.
青藏高原可可西里地区现代冰川发育特征   总被引:5,自引:1,他引:5  
李世杰 《地理科学》1996,16(1):10-17
经野外考察和室内分析计算,青藏可可西里地区发育现代冰川437条,覆盖面积达1552.39km^2,冰储量为162.8349km^3,成为本区众多河湖泊水体的重要补给源泉。  相似文献   

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