Aggregate clast form characteristics of deposits near the margins of four glaciers in the Jotunheimen Massif, Norway

Abstract

The form of a clast is defined by the relative dimensions of its three principal axes. Samples of clasts from deposits with different erosional ‘histories’ near the margins of four Jotunheimen glaciers revealed systematic differences in their aggregate form characteristics. Samples of frost-shattered detritus generally contain many ‘slabby’ clasts (low c:a axis ratios) but samples from subglacial deposits and talus do not. This distinction is relatable to the spacing of dilation joints in the parent rock. The potential for employing systematic differences in aggregate clast from characteristics in studies of glacial landforms and sediments is discussed.