Date: 26 Aug 2014
Recent This content was published within the last three months

Basal Sediment Evacuation by Subglacial Drainage Systems

This is an excerpt from the content

Definition

Basal sediment: The debris layer that exists at the ice–bedrock interface of a glacier or ice sheet and that is produced by glacial erosion of the underlying bedrock.

Basal sediment evacuation: The removal of basal sediment from the ice–bed interface by glacial and/or glaciofluvial sediment transport; most frequently used to describe the flushing of basal sediment from the ice–bedrock interface by subglacial water.

Subglacial drainage system: The network of drainage pathways at the ice–bed interface that convey water to the glacier margin or terminus.

Introduction

Contemporary observations and theoretical analyses demonstrate that, for Temperate Glaciers (qv), the entrainment and transport of basal sediment by fluvial processes dominates all other glacial sediment transport (Sediment Entrainment, Transport, and Deposition, qv) processes (see Hallet et al., 1996; Alley et al., 1997). Basal sediment evacuation by the Subglacial Drainage System ...