Glacial geomorphology of the Skálafellsjökull foreland, Iceland: A case study of ‘annual’ moraines

Small-scale recessional push moraines are a characteristic signature of the active temperate glacial landsystem, and are often clearly linked to annual re-advances. These recessional push moraines represent a potentially valuable terrestrial climate archive, and may provide valuable insights into glacier dynamics. This paper presents detailed glacial geomorphological maps of recessional push moraines on the foreland of Skálafellsjökull, SE Iceland. Geomorphological maps have been produced at a scale of 1:3750 based on 2006 aerial photographs and 2012 satellite imagery. Using unmanned aerial vehicle-captured imagery, large-scale sample mapping of two selected areas of the glacier foreland has also been conducted, with the maps reproduced as A4-sized figures at scales of ∼1:2500 and ∼1:2000, respectively. Desk- and field-based mapping reveals suites of recessional push moraines distributed across the glacier foreland, often found in close association with flutings. Moraines on the foreland typically display distinctive ‘sawtooth' planform geometries, with complexities in the pattern occurring due to localised superimposition. The inventory of glacial geomorphological maps presented here provides a framework for subsequently exploring the characteristics of the recessional push moraines and recent ice-marginal fluctuations at Skálafellsjökull.

小型后退推碛（recessional push moraines）是活动温带冰川地貌系统的典型特征标识，且常与年度冰进复进存在明确关联。这类后退推碛属于极具研究价值的陆地气候档案载体，可为冰川动力学研究提供重要见解。本研究绘制了冰岛东南部斯卡法尔斯约库尔（Skálafellsjökull）冰川前缘区域后退推碛的详细冰川地貌图（glacial geomorphological map）。本次冰川地貌图的成图比例尺为1:3750，数据基础为2006年航空摄影影像与2012年卫星遥感影像。本研究还利用无人机（unmanned aerial vehicle, UAV）采集的影像，对冰川前缘选定的两处区域开展了大比例尺样区测绘，最终成果以A4幅面插图形式呈现，比例尺分别约为1:2500与1:2000。室内编绘与野外实地测绘结果显示，冰川前缘广泛分布有成群的后退推碛，且常与冰川刻槽（fluting）紧密伴生。该冰川前缘的推碛通常呈现独特的“锯齿状”平面形态，局部叠加作用会导致碛体分布模式出现复杂变化。本研究提供的冰川地貌图数据集，可为后续探究斯卡法尔斯约库尔冰川的后退推碛特征与近期冰缘波动情况提供研究框架。