Austre Lovénbreen: the glacier forefieldThe glacier forefield is particularly interesting because of the wide range of landforms and the processes in operation. Landforms include an outer belt of a moraine-mound complex (hummocky moraine), sheets of diamicton (basal till) resting on weathered bedrock, flutes, supraglacial debris-stripes derived from medial moraines, glaciofluvial sediments and kettle ponds. There is also extensive geochemical precipitation of iron-rich and siliceous minerals, probably toxic and bearing some resemblance to acid-mine drainage, although totally natural. |
![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/0_austre_lovenbreen.jpg) Weak sunlight, diffused by cirrostratus clouds, is reflected in a meltstream flowing from the snout of Austre Lovénbreen. (JA) | ![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/1_austre_lovenbreen_mtn_front.jpg) Telephoto view along the Brřggerhalvřya mountain front, denoting the boundary between the mountainous Neoproterozoic metamorphic rocks and younger (Carboniferous, Tertiary) strata; viewed from Austre Lovénbreen. (MH) | ![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/2_austre_lovenbreen_proglacial_stripes.jpg) Stripes of angular debris, extending across the forefield of Austre Lovénbreen, are derived from medial moraines. The orange coloured areas denote seepage of geochemically (iron-) rich waters from bedrock. (MH) | ![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/3_austre_lovenbreen_erosion.jpg) Extensive areas of the proglacial area of Austre Lovénbreen are draped with diamicton (interpreted as basal till), but where meltwater emerges from the glacier, this sheet is dissected. (MH) |
![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/4_austre_lovenbreen_weathered_bedrock.jpg) Brown subglacially derived meltwater has here cut down both through the basal till and the weathered Carboniferous bedrock. (MH) | ![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/5_angular_debris.jpg) Angular debris of supraglacial (rockfall) derivation draped over the basal till in the forefield of Austre Lovénbreen. (MH) | ![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/6_angular-erratic.jpg) Large solitary angular boulder of conglomerate (an erratic) on the forefield of Austre Lovénbreen, probably displaced from the bed locally. (MH) | ![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/7_striated_limestone_clast.jpg) Beautifully striated boulder of limestone, lodged in the basal till on the forefield of Austre Lovénbreen. (MH) |
![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/8_dissected_glaciofluvial.jpg) Glaciofluvial deposits at the SE margin of Austre Lovénbreen, showing dissection by a succession of glacial meltwater channels. (MH) | ![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/9_glaciofluvial_crossbedding.jpg) Cross-section through the glaciofluvial gravels, illustrating their steep prograded nature from rapid deposition and contact with basal glacial sediment. (MH) | ![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/10_fractured_bedrock.jpg) Heavily fractured and weathered bedrock in front of Austre Lovénbreen, with blocks partly displaced by glacial erosion. (MH) | ![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/11_collapsed_till.jpg) Here the bedrock is largely covered by diamicton (interpreted as basal till), but shows collapse features in the bedrock. (MH) |
![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/12_snout_geochemical_areas.jpg) View of snout of Austre Lovénbreen from the NW, illustrating a large area affected by geochemically rich waters. (MH) | ![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/13_mineralised_waterfall.jpg) Small waterfall near snout of Austre Lovénbreen, illustrating orange (iron-rich) and white (siliceous) chemical precipitates. (MH) | ![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/14_ironstained_mud.jpg) Close-up view of orange iron-stained mud resulting from precipitation from water oozing from the bedrock. (MH) | ![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/15_orange_white_mineralisation.jpg) Close-up view of orange iron-coated pebbles, resting on a silicified stream bed. (MH) |
![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/16_organge_weathering_cobble.jpg) This striking orange iron-coated cobble was found lying on a fluvially modified part of the proglacial area of Austre Lovénbreen. (MH) | ![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/17_austre_lovenbreen_moss.jpg) Moss clump growing on the outer Neoglacial moraine of Austre Lovénbreen. (MH) | ![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/18_reindeer_skull.jpg) Complete reindeer skull with antlers found on the proglacial area of Austre Lovénbreen. (MH) | ![Austre Lovénbreen: the glacier forefield Austre Lovénbreen: the glacier forefield](icons/19_austre_lovenbreen_kettle_pond.jpg) Mountains at the head of Austre Lovénbreen are reflected in this kettle pond in the glacier’s outer moraine. (MH) |
Most of these photographs were taken in July-August 2009. The glacier and its forefield have been described in the following papers:
Glasser, N. F. and Hambrey, M. J. 2001. Styles of sedimentation beneath Svalbard valley glaciers under changing dynamic and thermal regimes. Journal of the Geological Society, London 158(4), 697-707.
Hambrey, M. J. and Glasser, N. F. 2003. The role of folding and foliation development in the genesis of medial moraines: examples from Svalbard glaciers. Journal of Geology 111, 471-485.
|