Moraine forms and genesis

Abstract

Moraines are accumulations of sediment/debris on the surface or at the margins of ice sheets and glaciers and hence their distribution can be used to reconstruct the patterns of glacier and ice sheet advance and recession in terrestrial and subaqueous environments. The various process-form regimes of moraine construction reflect the dynamics and thermal characteristics of the ice margins responsible for their construction. This facilitates and understanding of spatio-temporal change in palaeoglaciological reconstruction. Terrestrial moraines include push and squeeze moraines, dump moraines and ice-marginal aprons, and latero-frontal moraines and fans and ramps. Supraglacial debris accumulations form medial moraines, hummocky moraine and controlled moraine. Subaqueous depo-centers include morainal banks, coalescent subaqueous fans, and De Geer moraines, all of which document the operation of glacilacustrine and glacimarine depositional processes in ice-contact environments in combination with glacitectonic disturbance and till emplacement. Ice shelf moraines form at the interface between subaqueous and terrestrial environments where they document the existence of cold-based, floating ice margins.