唐古拉山中西段冰川槽谷形态及其影响因素分析

冰川槽谷作为典型的冰川侵蚀地貌,研究其形态特征和影响因素有助于更全面地认识冰川发育模式和侵蚀特征。本文以唐古拉山中西段为研究区,运用V指数模型和地理探测器模型,分析探讨了区内冰川槽谷形态发育特征,并对其影响因素进行了研究。结果表明：冰川槽谷横剖面的V指数与幂函数b值在槽谷对称的情况下可以相互替代,且典型冰川槽谷横剖面的V指数介于0.20~0.43之间。研究区保存着“箱形”形态的冰川槽谷,其V指数具有接近于1的特征。区内冰川槽谷横剖面V指数<0.20的占比19%,V指数介于0.20~0.43之间的占比48%,V指数>0.43的占比33%,表明研究区内呈典型“U”形的槽谷数量最多。此外,北坡主要发育典型“U”形的冰川槽谷,占比高达60%,而南坡各种形态的槽谷数量相当。研究区内山谷冰川发育区、过渡区槽谷呈典型“U”形的占比最多,而冰帽发育区槽谷近似“箱形”的占比最多。应用地理探测器对影响冰川槽谷形态特征的因素进行评价,最主要的影响因素有冰川作用区面积因素和冰川作用正差因素,其次是岩性因素,再次是坡度和地形起伏度因素,最后是冰川性质和槽谷朝向因素。冰川作用区面积因素和坡度因素的交互作用对冰川槽谷形态特征的影响最为显著。     

基于V指数的他念他翁山中段冰川槽谷形态特征及影响因素分析

冰川槽谷作为冰川作用区分布最典型的冰川地貌之一,对其形态特征及影响因素的研究,有助于揭示冰川发育的动力学过程。基于V指数模型及MATLAB半自动提取方法,分析并探讨了他念他翁山中段冰川槽谷形态发育特征及造成槽谷形态差异的影响因素。结果表明：研究区共发育206条冰川槽谷,大多为“U”形或偏“U”形,长4.5~26 km之间,平均宽度1.8 km,深200~500 m,海拔高度介于5 730~3 274 m。槽谷形态横向分布规律：V指数多为0.2~0.3,北东向发育V指数大于0.3的谷地多于西南向,说明东坡槽谷侵蚀程度强于西坡。V指数沿槽谷纵向主要有两种变化趋势：V指数增大,冰川槽谷横剖面“U”形发育特点逐渐增强;V指数减小,冰川槽谷横剖面“U”形发育特点减弱。研究区冰川槽谷发育以侧蚀为主,形态的差异性是冰川自身特性、冰川作用区地形与基岩岩性等多种因素共同作用的结果。其中,冰川作用区的平均坡度、平均地形起伏度与古冰川作用区面积是造成这种分布差异的主要因素。     

冰川槽谷横剖面形态特征探析

基于对天山中、西部冰川槽谷的量算,并对比国内外不同匠研究成果,利用冰川槽谷横剖面的幂函数模型探讨了冰川槽谷的横剖面形态特征,研究表明,本区槽谷的ｂ－ＦＲ关系并不完全符合Ｈｉｒａｎｏ和Ａｎｉｙａ提出的山地冰川模式,而是有自身的形态特征,但槽谷剖面形态参数Ａ、ｂ之间具有明显的结性关系,并具有很强的普遍性,可以作为冰川槽谷横剖面形态的判别标准。     

白马雪山冰川槽谷发育的形态特征及其影响因素探讨

白马雪山地处横断山脉腹地,对于重建西南季风影响区的环境变迁以及探讨冰川作用特点具有重要科学意义.这里保留着典型的晚第四纪冰川侵蚀地貌,其中冰川槽谷发育特征明显.本文运用抛物线形态参数、梯级宽深比、形态比率等定量分析冰川槽谷的研究方法,对保存在白马雪山主峰扎拉雀尼(5429m)东北坡的两条简单冰川槽谷的形态特征进行分析.采用7个典型剖面的形态特征参数与其他地区对比,探讨冰川槽谷发育的可能影响因素如水热条件、冰川性质、冰川规模、岩性特点、冰川作用时间等.结果显示:白马雪山冰川槽谷抛物线形态参数b值为1.779,明显小于冰川性质相同的螺髻山(1.835),主要是由于区域降水条件的不同所造成的差异,而与冰川性质不同天山乌鲁木齐河源区(1.825)冰川槽谷的形态特征的差异,可能与冰川规模、作用时间以及岩性条件密切相关;梯级宽深比中槽谷形态参数沿程变化可以反映冰川流动过程中的动力变化,梯级宽深比中的形态参数Af和Bf值最大处对应的谷肩位置接近雪线位置.根据槽谷谷肩的位置确定末次冰期早期/中期的雪线高度为4140m,这与用地貌法如冰斗底部高程法、侧碛堤最大高度法和冰川末端至冰斗后壁最大高度法等综合确定的雪线高度4092m基本一致.因此,在冰川槽谷发育的冰川作用区,用槽谷谷肩的海拔高度估算雪线高度可以成为一种比较可靠的确定古雪线方法;白马雪山的冰川槽谷形态参数b-FR的特征表明,即使是海洋性冰川作用区也不符合Hiran和Aniya提出的山地冰川模式,但运用b-FR相关关系可以很好的反映冰川的侵蚀过程.白马雪山地区冰川侧蚀作用导致槽谷坡降值较小,底部较平坦宽阔,呈现出相对完整的U型形态.此外,用形态比率FR值也可以验证雪线的位置高度.     

四川康定折多山末次冰盛期古冰川重建及其气候意义

折多山位于青藏高原东缘,地势上处于由高原面向高山峡谷的过渡区,古冰川遗迹保留较好。对折多山冰川地貌进行深入研究,对揭示青藏高原东缘地形演化与古气候变化的耦合机制具有重要意义。在野外考察的基础上,结合Google Earth遥感影像、《中国第二次冰川编目》和DEM等资料,对折多山冰川地貌及其特征参数进行了识别、提取和计算。研究共识别出189条古冰川,覆盖面积为497 km²。基于研究区已有年代学资料,本区冰川地貌主要为末次冰盛期（LGM）以来冰川作用遗存。恢复研究区LGM冰川平衡线高度（ELA）,在西坡和东坡分别为4 380 m和4 110 m,相差270 m,揭示出分水岭东侧更有利于冰川发育。广泛发育的冰蚀湖、冰蚀基岩面、羊背石等,以及深切的冰川槽谷（U形谷）指示海洋性冰川作用特征;冰川作用正差、冰川朝向、冰蚀地貌的差异,揭示积累区地形条件和水汽来源对研究区冰川发育具有重要的影响。     

祁连山老虎沟12号冰川雷达测厚和冰下地形特征研究

冰川地形是构建冰川流动模型的基础,对于认识冰川响应气候变化的动力机制具有重要意义.在2009年和2014年消融季,使用探地雷达对祁连山老虎沟12号冰川进行了厚度测量和冰下地形观测,获得了沿冰川中流线和多条横剖面的厚度资料,并对中流线上的厚度分布特征和槽谷形态进行了研究.研究结果表明,东、西支冰川的平均厚度分别为190m和150m,东支冰川冰下地形起伏大于西支,支冰川的表面坡度都较缓和.东、西支冰川进入汇合区时厚度分别为122m和157m,由于支冰川的横向挤压和汇流,汇合区中部冰川厚度增加到162m.冰川槽谷形态具有空间差异,东、西支冰川槽谷形态近似于对称的V型,但是在冰川汇合区,槽谷底部变宽,边坡变缓,发育有不对称槽谷.     

山地冰川演化与冰湖发育相互作用机制北大核心CSCD

冰川-冰湖耦合过程是冰冻圈物质与能量循环的重要组成部分,系统刻画冰川演化与冰湖发育过程的相互作用机制,对于完善冰冻圈科学理论体系和认知冰川作用区变化规律、水循环模式和灾害效应具有重要意义。本文立足山地冰川演化和冰湖发育过程,系统归纳了冰川-冰湖相互作用研究进展,剖析了冰川作用与冰湖发育耦合机制及相关模型的应用,并对现有冰川演化与冰湖发育过程耦合机制研究存在的不足与挑战进行解析和总结。冰川-冰湖耦合过程的深入研究有助于提高数值模拟的可信度与精度,为评估冰川-冰湖耦合过程影响、建立灾害监测预警体系和采取适应性措施提供数据与理论基础。     

关于山谷冰川冰—岩界面地貌过程与冰川动力耦合模式——以中天山冰…

对冰川侵蚀形态的观测与分析得知：（１）冰川槽谷中冰川擦痕的大小和密度在中心较大，鲸背岩出现在冰种槽谷的中部、羊背石发育在槽谷两侧。因此，可以将槽谷分为强烈磨蚀的中部和弱磨蚀而强拔蚀的两侧。（２）冰坎的纵剖面上，迎冰面可见鲸背岩、羊背石以及倾角２０°的剪切裂隙；背冰面以拔蚀为主，见倾角４０°的张性裂隙，沿冰川槽谷纵向，剪切裂隙出现在压缩部位，张裂隙出现在伸张部位，它反映出冷底冰川的动力特性与冰床基岩     

关于山谷冰川冰-岩界面地貌过程与冰川动力耦合模式——以中天山冰川为例

对冰川侵蚀形态的观测与分析得知：（１）冰川槽谷中冰川擦痕的大小和密度在中心较大，鲸背岩出现在冰川槽谷的中部，羊背石发育在槽谷两侧。因此，可以将槽谷分为强烈磨蚀的中部和弱磨蚀而强拔蚀的两侧。（２）冰坎的纵剖面上，迎冰面可见鲸背岩、羊背石以及倾角２０°的剪切裂隙；背冰面以拔蚀为主，见倾角４０°的张性裂隙。沿冰川槽谷纵向，剪切裂隙出现在压缩部位，张裂隙出现在伸张部位。它反映出冷底冰川的动力特性与冰床基岩的受力机制的一致性。     

川西螺髻山冰川侵蚀地貌研究

定量分析发现影响该地区冰斗形态的因素有海洋性较强的气候,朝向北(极向),朝向东和较大的地形起伏四种。槽谷的横剖面可以公式化为Y=a·X~b,槽谷形态不对称由冰川差异侵蚀和冻融差异所致。发现两种冰川侵蚀裂痕,即挤压剪切裂痕和拉张剪切裂痕。     

Multiple Quaternary erosion and infill cycles in overdeepened basins of the northern Alpine foreland

The cumulative effect of repeated extensive glaciations represents a poorly constrained component in the understanding of landscape evolution in mid-latitude mountain ranges such as the Alps. Timing, extent, and paleo-climatic conditions of these glaciations are generally poorly understood due to the often-fragmentary character of terrestrial Quaternary records. In this context, the sedimentary infills of subglacial basins may serve as important archives to complement the Quaternary stratigraphy over several glacial–interglacial cycles. In this study, sedimentary facies, valley-fill architecture, and luminescence dating are used to describe nine erosional and depositional cycles (Formations A–I) in the Lower Glatt valley, northern Switzerland. These cycles can be related to the ‘Birrfeld’ Glaciation (~ MIS2), the ‘Beringen’ Glaciation (~ MIS6), and up to three earlier Middle Pleistocene glaciations that can be tentatively correlated to the regional glaciation history. Evidence suggests that deep bedrock trough incision and/or partial re-excavation last occurred mainly during the ‘Beringen’ and ‘Habsburg’ Glaciations. Second-order, ‘inlaid’ glacial basins document separate glacier re-advances during the Beringen Glaciation. The arrangement of subglacial basins in the Glatt valley with different sub-parallel or bifurcating bedrock troughs, re-excavated segments, and inlaid basins document changes in the magnitude and the spatial focus of subglacial erosion over time. The Glatt valley may thus serve as a key example for the glacial landscape evolution in many other repeatedly glaciated forelands.     

天山夏特河流域晚第四纪冰川沉积序列与地貌演化

夏特河源于天山最大现代冰川作用中心托木尔—汗腾格里峰的东北坡,流域内保存有形态较为清晰的四套冰川沉积。这些地形记录了夏特河流域的古冰川变化,对它们进行研究可获得该地晚第四纪以来的冰川时空演化规律。在第三套冰碛夹层中的砂质透镜体里采集了5个OSL年代学样品,应用单片再生（SAR）测年技术测得它们的年龄为（13.3±0.8）~（20.1±1.3） ka。基于测年结果、各套冰碛距现代冰川的远近、冰碛垄的完整程度、冰碛物的风化胶结状况及接触关系,并参阅托木尔—汗腾格里峰南坡与东南坡以及东、中、西段天山其他流域的年代学资料,可初步得出：第一套和第二套冰碛分别沉积于小冰期和新冰期;第三套冰碛形成于末次盛冰期及随后的冰消期,可对应于海洋氧同位素阶段（MIS） 2;保存在河口的第四套冰川沉积及与其相关联的宽阔且长达数十千米的“U”形谷共同指示,它应形成于冰川规模较大的倒数第二次冰期,时间上可对应于MIS 6。     

Style and timing of glaciation in the Lahul Himalaya,northern India: a framework for reconstructing late Quaternary palaeoclimatic change in the western Himalayas

This paper presents a revised glacial chronology for the Lahul Himalaya and provides the most detailed reconstruction of former glacier extents in the western Himalayas published to date. On the basis of detailed geomorphological mapping, morphostratigraphy, and absolute and relative dating, three glaciations and two glacial advances are constrained. The oldest glaciation (Chandra glacial stage) is represented by glacially eroded benches and drumlins (the first to be described from the Himalaya) at altitudes of >4300 m and indicates glaciation on a landscape of broad valleys that had minimal fluvial incision. The second glaciation (Batal glacial stage) is represented by highly weathered and disssected lateral moraines and drumlins representing two phases of glaciation within the Batal glacial stage (Batal I and Batal II). The Batal stage was an extensive valley glaciation interrupted by a readvance that produced superimposed bedforms. Optically stimulated luminescence (OSL) dating, indicates that glaciers probably started to retreat between 43400 ± 10300 and 36900 ± 8400 yr ago during the Batal stage. The Batal stage may be equivalent to marine Oxygen Isotope Stage 4 and early Oxygen Isotope Stage 3. The third glaciation (Kulti glacial stage), is represented by well-preserved moraines in the main tributary valleys that formed due to a less-extensive valley glaciation when ice advanced no more than 12 km from present ice margins. On the basis of an OSL age for deltaic sands and gravels that underlie tills of Kulti age, the Kulti glaciation is younger than 36900 ± 8400 yr ago. The development of peat bogs, having a basal age of 9160 ± 70 ¹⁴C yr BP possibly represents a phase of climatic amelioration coincident with post-Kulti deglaciation. The Kulti glaciation, therefore, is probably equivalent to all or parts of late Oxygen Isotope Stage 3, Stage 2 and early Stage 1. Two minor advances (Sonapani I and II) are represented by small sharp-crested moraines within a few kilometres of glacier termini. On the basis of relative weathering, the Sonapani advance is possibly of early mid-Holocene age, whereas the Sonapani II advance is historical. The change in style and extent of glaciation is attributed to topographic controls produced by fluvial incision and by increasing aridity during the Quaternary. © 1997 John Wiley & Sons, Ltd.     

The Glacial History of Landscape in the Batura Muztagh, NW Karakoram

The most recent glacial history of the Bar Valley on the Batura south side of the great Karakorum main ridge shows a marked retreat of the Kukuar and Baltar glaciers since 1915 by 8 km. This tendency is continuing. A great lateral moraine (GLM), which shows the latest, historical maximum postglacial stage, is accompanied by a higher level, which reflects a neoglacial glacier level whose ice margins no longer exist. An earth-pyramid moraine rising high above the glacier, as also occurs on the northern declivities of the Batura, does not mark a specific level, but bears witness to a valley-filling glacier, for which further indicators can be found along the valley flank. In the gorge-like narrow trough valley, the flanks of which are covered by steep debris cones originating from the postglacial, numerous former glacial characteristics contrast with the current glaciation of the far retreated Kukuar and Baltar glaciers. Moraine material found at the valley outlet at Chalt and also on the Talmutz pass demonstrates complete ice filling of the Bar valley, also supported by the Daintar glacier. From a glacial geomorphological perspective, this confirms a late to high glacial connection of the Bar glacier to a Hunza glacier, as postulated by Kuhle (2005).     

The glacial history of landscape in the Batura Muztagh, NW Karakoram

The most recent glacial history of the Bar Valley on the Batura south side of the great Karakorum main ridge shows a marked retreat of the Kukuar and Baltar glaciers since 1915 by 8 km. This tendency is continuing. A great lateral moraine (GLM), which shows the latest, historical maximum postglacial stage, is accompanied by a higher level, which reflects a neoglacial glacier level whose ice margins no longer exist. An earth-pyramid moraine rising high above the glacier, as also occurs on the northern declivities of the Batura, does not mark a specific level, but bears witness to a valley-filling glacier, for which further indicators can be found along the valley flank. In the gorge-like narrow trough valley, the flanks of which are covered by steep debris cones originating from the postglacial, numerous former glacial characteristics contrast with the current glaciation of the far retreated Kukuar and Baltar glaciers. Moraine material found at the valley outlet at Chalt and also on the Talmutz pass demonstrates complete ice filling of the Bar valley, also supported by the Daintar glacier. From a glacial geomorphological perspectives, this confirms a late to high glacial connection of the Bar glacier to a Hunza glacier, as postulated by Kuhle (2005).     

北京西山潭柘寺地区第四纪冰川与环境问题

第四纪时期,北京西山潭柘寺地区没有发生过任何山地冰川作用。所渭的冰川遗迹、冰碛、冰水沉积及各种冰蚀地貌,实际上是不存在的。因此,所渭的冰期划分也都是不可靠的。在更新世冰期阶段,北京西山属冰缘环境,而非冰川环境。     

Connectivity analyses of valley patterns indicate preservation of a preglacial fluvial valley system in the Dyfi basin, Wales

Coastal valleys in the west part of Mid-Wales, such as the Mawddach, Dysynni, Tal-y-llyn and Dyfi, acted as corridors for ice which drained the Welsh Ice Cap during the Devensian. Analyses of detailed digital elevation models, and interpretation of satellite images and aerial photographs, show the existence of large variations in the amount of glacial modification between these valleys. Although all the valleys are glacially over-deepened along late Caledonian fault lines, only the Dyfi basin exhibits a dendritic pattern, with V-shaped cross-profiles and valley spurs typical of valleys formed by fluvial processes. Connectivity analysis of the Dyfi basin shows that it exhibits an almost completely dendritic pattern with connectivity α and β values of 0.74 and 1.01, respectively, with little glacial modification of the preglacial fluvial valley pattern in the form of glacial valley breaching. Several examples of glacial meltwater incision into a well-developed pre-existing river valley system, causing river capture across watersheds, have been identified in the Dyfi basin. The degree of preservation of the preglacial fluvial valley system within the Dyfi basin indicates limited modification by glacial processes, despite the area being subjected to glacier activity during the Late Devensian at least. It is possible that major parts of the basin were covered by cold-based or slow-moving ice, close to, or under, a migrating ice-divide, with the major ice drainage occurring along the weaker zone of the Pennal Fault along which teh Dyfi valley is located, causing minor adjustments to the surrounding interfluves and uplands. It is proposed here that the general river valley morphology of the Dyfi basin is of a pre-Late Devensian age.