The geomorphology of Svínafellsjökull and Virkisjökull-Falljökull glacier forelands, southeast Iceland

ABSTRACT A detailed, 1:10,500-scale, surficial geology and glacial geomorphology map of Svínafellsjökull and Virkisjökull-Falljökull glacier forelands in southeast Iceland depicts the landsystem imprint of Holocene glacier fluctuations, volcanogenic outburst floods and recent (post-1990) climate-induced rapid ice-front retreat. The map is based on field survey data in combination with 2012 airborne LiDAR data, 2009–2012 terrestrial LiDAR data and 2007 colour aerial photography. The base digital elevation model (DEM) is compiled from an ice-cap wide airborne LiDAR dataset. The mapped glacial landforms are dominated by sequences of recessional moraines laid down in the mid-Holocene, the Little Ice Age, and the last ∼100 years; the state of landform preservation generally decreasing with age. Interspersed with glaciofluvial sedimentation associated with typical ice-marginal retreat sequences is key geomorphological evidence of high-magnitude volcanogenic outburst floods (jökulhlaups) associated with the eruptions of Öraefajökull in 1362 and 1727 CE. Ice-front retreat has accelerated since c.2005 leaving a rapidly evolving buried-ice landscape in front of Virkisjökull-Falljökull – including an ice-cored esker, a large ice-floored (supraglacial) lake, and numerous actively forming kettle holes and ice caverns. This map could act as a ‘reference frame’ for geomorphologists studying the temporal evolution of glacial landform-sediment assemblages undergoing rapid change.

[1]  L. Jones,et al.  Concentrated, ‘pulsed’ axial glacier flow: structural glaciological evidence from Kvíárjökull in SE Iceland , 2017 .

[2]  N. Eyles,et al.  Joint-bounded crescentic scars formed by subglacial clast-bed contact forces: Implications for bedrock failure beneath glaciers , 2017 .

[3]  A. Black,et al.  Using stable isotopes and continuous meltwater river monitoring to investigate the hydrology of a rapidly retreating Icelandic outlet glacier , 2015, Annals of Glaciology.

[4]  A. Black,et al.  Meltwater flow through a rapidly deglaciating glacier and foreland catchment system: Virkisjökull, SE Iceland , 2015 .

[5]  G. Aðalgeirsdóttir,et al.  Variations of southeast vatnajökull ice cap (iceland) 1650–1900 and reconstruction of the glacier surface geometry at the little ice age maximum , 2015 .

[6]  Helgi Björnsson,et al.  Changes in the southeast Vatnajökull ice cap, Iceland, between ~ 1890 and 2010 , 2015 .

[7]  O. Solomina,et al.  Holocene glacier fluctuations , 2015 .

[8]  L. Jones,et al.  Structural evolution triggers a dynamic reduction in active glacier length during rapid retreat: Evidence from Falljökull, SE Iceland , 2014 .

[9]  T. Bradwell,et al.  Recent, very rapid retreat of a temperate glacier in SE Iceland , 2013 .

[10]  L. Jones,et al.  Fracturing, block faulting, and moulin development associated with progressive collapse and retreat of a maritime glacier: Falljökull, SE Iceland , 2013 .

[11]  Helgi Björnsson,et al.  Ice-volume changes, bias estimation of mass-balance measurements and changes in subglacial lakes derived by lidar mapping of the surface of Icelandic glaciers , 2013, Annals of Glaciology.

[12]  Helgi Björnsson,et al.  Breiðamerkurjökull , 2010, Jökull.

[13]  V. Jomelli,et al.  Asynchronous Little Ice Age glacial maximum extent in southeast Iceland , 2010 .

[14]  David J. A. Evans,et al.  Satujökull glacial landsystem, Iceland , 2010 .

[15]  P. Carbonneau,et al.  Evolution of a debris-charged glacier landsystem, Kvíárjökull, Iceland , 2010 .

[16]  David J. A. Evans,et al.  Glacial Geomorphology at Glasgow , 2009 .

[17]  David J. A. Evans,et al.  Surging glacier landsystem of Tungnaárjökull, Iceland , 2009 .

[18]  David J. A. Evans,et al.  Surficial geology and geomorphology of the Brúarjökull surging glacier landsystem , 2007 .

[19]  David J. A. Evans,et al.  Subglacial till: Formation, sedimentary characteristics and classification , 2006 .

[20]  David J. A. Evans,et al.  Surficial geology and geomorphology of the þórisjökull plateau icefield, west-central Iceland , 2006 .

[21]  D. McGarvie,et al.  Subglacial and ice-contact volcanism at the Öræfajökull stratovolcano, Iceland , 2005 .

[22]  J. Oerlemans.  Extracting a Climate Signal from 169 Glacier Records , 2005, Science.

[23]  T. Bradwell.  Lichenometric dating in southeast iceland: the size–frequency approach , 2004 .

[24]  T. Bradwell,et al.  Buried glacier ice in southern Iceland and its wider significance , 2003 .

[25]  David J. A. Evans,et al.  The active temperate glacial landsystem: a model based on Breiðamerkurjökull and Fjallsjökull, Iceland , 2002 .

[26]  David J. A. Evans,et al.  Sediments and landforms at Kvı́árjökull, southeast Iceland: a reappraisal of the glaciated valley landsystem , 2002 .

[27]  T. Bradwell.  A new lichenometric dating curve for southeast iceland. , 2001 .

[28]  David J. A. Evans,et al.  A gravel outwash/deformation till continuum, skalafellsjokull, iceland , 2000 .

[29]  John H. Powell,et al.  BGS rock classification scheme. Volume 4, classification of artificial (man-made) ground and natural superficial deposits : applications to geological maps and datasets in the UK , 1999 .

[30]  O. Sigurðsson.  Glacier variations in Iceland 1930–1995. From the database of the Iceland Glaciological Society , 1998, Jökull.

[31]  Helgi Björnsson,et al.  Hydrological characteristics of the drainage system beneath a surging glacier , 1998, Nature.

[32]  J. Maizels.  Jökulhlaup deposits in proglacial areas , 1997 .

[33]  A. Thompson.  Historical development of the proglacial landforms of Svínafellsjökull and Skaftafellsjökull, Southeast Iceland , 1988 .

[34]  G. Boulton,et al.  Sediment deformation beneath glaciers: Rheology and geological consequences , 1987 .

[35]  N. Eyles.  Facies of supraglacial sedimentation on Icelandic and Alpine temperate glaciers , 1979 .

[36]  Sigurður Þórarinsson.  The Öræfajökull eruption of 1362 , 1958 .

[37]  Sigurður Þórarinsson.  On the variations of Svínafellsjökull, Skaftafellsjökull and Kvíárjökull in Öræfi (Ágrip) , 1956, Jökull.

[38]  S. Thorarinsson.  Chapter XI. Oscillations of the leeland Glaciers in the làst 250 Years , 1943 .

[39]  S. Thorarinsson.  Vatnajokull, Scientific results of the Swedish-Icelandic Investigations 1936-37-38. Part XI Oscillations of the Icelandic glaciers in the last 250 years , 1943 .