Abstract A boulder-dominated landform assemblage in an alpine setting in Norway is described, interpreted and dated using a combination of Schmidt-hammer exposure-age dating (SHD) and cosmogenic 10Be surface-exposure dating. The origin and formation of these features is determined from their morphology, topographic setting and age. Three main components of the assemblage are recognized. First a ~300 m long and ~160 m wide, tongue-shaped rock-slope failure with a SHD age of 11.49 ± 0.82–12.96 ± 0.86 ka is identified on the basis of its planform, thickness, ‘runout distance’ and association with a fractured backing scarp. This is interpreted as a relict paraglacial landform triggered by deglaciation. Second, a 400-m long unequivocal pronival (protalus) rampart with an SHD age of 6.95 ± 0.97–8.35 ± 1.21 ka is identified on the basis of its narrow ridge form aligned close to the foot of an extensive talus slope. Although formation of the rampart probably commenced with deglaciation, the younger SHD ages indicate formation at a diminishing rate through the Holocene. Third, a ~550 m by ~150 m lobate component with transverse ridges, longitudinal and transverse depressions and enclosed pits, previously identified as a rock glacier, is dated to 11.33 ± 0.83–13.33 ± 0.90 ka with the Schmidt hammer and between 13.3 ± 2.0–14.7 ± 2.0 ka with 10Be. This third component may also be a product of rock-slope failure but attribution to rock-glacier creep associated with either interstitial ice (permafrost) or buried glacier ice during the Allerod Interstadial – Younger Dryas Stadial, and to which one or more rock-slope failures contributed debris, cannot be rejected. The advantages and limitations of compiling such evidence for identifying, differentiating and classifying apparently similar boulder-dominated colluvial landforms are exemplified.

中文翻译：

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挪威南部 Romsdalsalpane Alnesdalen 残存的冰缘和冰缘巨石主导地貌组合​​的解释、年龄和意义

摘要 结合施密特锤曝光年代测定法 (SHD) 和宇宙成因 10Be 表面曝光年代测定法，对挪威高山环境中以巨石为主的地貌组合进行了描述、解释和测年。这些特征的起源和形成是由它们的形态、地形环境和年龄决定的。该组合的三个主要组成部分是公认的。首先，根据其平面、厚度、“跳动距离”和与断裂的背脊。这被解释为冰川消退引发的残余冰河边地貌。其次，一个 400 米长的明确的前体（protalus）城墙，SHD 年龄为 6.95 ± 0.97–8.35 ± 1。21 ka 是根据其狭窄的山脊形状而确定的，该山脊形状靠近广泛的距骨斜坡的脚部。虽然城墙的形成可能始于冰川消退，但较年轻的 SHD 年龄表明，在全新世期间形成的速度正在下降。第三，一个 ~550 m x ~150 m 的叶状组件，具有横向脊、纵向和横向凹陷以及封闭的坑，以前被确定为岩石冰川，用施密特锤测得的时间为 11.33 ± 0.83–13.33 ± 0.90 ka，介于 13.3 ± 2.0–14.7 ± 2.0 ka，含 10Be。这第三个组成部分也可能是岩石斜坡破坏的产物，但归因于在 Allerod Interstadial – Younger Dryas Stadial 期间与间隙冰（永久冻土）或掩埋冰川冰相关的岩石冰川蠕变，以及一个或多个岩石斜坡故障造成碎片，不能被拒绝。举例说明了收集此类证据以识别、区分和分类明显相似的以巨石为主的崩积地貌的优点和局限性。