Holocene relative sea-level change and deglaciation on Alexander Island, Antarctic Peninsula, from elevated lake deltas.

摘要: Abstract Field data constraining the rate and spatial pattern of deglaciation relative sea-level (RSL) change on Antarctic Peninsula (AP) are relatively sparse, but needed to improve regional ice sheet RSL models, contribute better model predictions future rise. We investigated geomorphology, sedimentology quartz-fraction single aliquot regeneration optically-stimulated luminescence (SAR-OSL) geochronology elevated deltas around two epishelf lakes, Ablation Lake (AL) Moutonnee (ML), Alexander Island, Peninsula. AL ML dammed by George VI Ice Shelf, maintain a direct hydraulic connection sea; hence, their water levels controlled changes in RSL. Our aim was provide new terrestrial constraints for southern AP comparing formation processes, age altitude with: (1) existing curves AP; (2) isostatically-coupled (3) history SAR-OSL ages from nearby inland Hodgson (HL). Although there insufficient quartz samples dating, 4.6 ± 0.4 ka delta at represents last time active were forming higher than present day lake level, implies: fall up 14.4 m since mid-Holocene this part which is consistent with field-based chronologies smaller masses suggested some (but not all) models mid-Holocene, significant thinning sheets, sediment core cosmogenic exposure ages, 4.4 ± 0.7 ka lowermost HL delta.