ICEGRAV

ICEGRAV

Start date
1 September, 2012
End date
1 September, 2013

The ICEGRAV project is a major international collaboration between Danish, US, UK, Norwegian and Argentinian scientists. The primary aim of the project is to carry our airborne gravity observations across hitherto unexplored parts of Antarctica. Additional radar and aeromagnetic observations further contribute to filling major data voids.

The ICEGRAV 2013 season focused on exploring and understanding the Recovery Catchment, from the coast to the massive Recovery Subglacial Lakes ~750 km into the continental interior. This glacier catchment is potentially susceptible to significant change, due to variation in the Ronnie Filchner Ice shelf, yet before this project, the subglacial topography and underlying geology of this catchment remained un-resolved.

Ice velocity map and ICEGRAV 2013 survey lines. Yellow triangles mark operational bases and field camps. Dark blue outlines locate Recovery lakes, while pale blue outlines indicate dynamic lakes identified by satellite observations.

Additional information about the ICEGRAV 2010 survey over the Antarctic Peninsula can be found at: www.martagh.com.ar/icegrav2010 

The overarching aim of the ICEGRAV 2013 survey was to collect high quality gravity, magnetic and radar data across the catchments of the Recovery, and adjacent Baily and Slesor glaciers. This data will contribute to work across a range of scientific disciplines.

For geophysics our goal is to better comprehend the nature of the tectonic features and deeper crustal architecture of one of the last geological frontiers on Earth, the East Antarctic shield. Little is known about the geology and tectonic architecture of our survey region, due to the lack of geophysical data and rock exposures. However, studies in West Antarctica show that the underlying geology plays a key role in determining the pattern of flow in the overlying ice sheet. When combined with preceding ICEGRAV surveys and major adjacent surveys performed by AWI, the ICEGRAV 2013 will provide unique new insights into sub-ice geology and crustal architecture of the East Antarctic Shield.

For glaciology the main scientific output will be new radar measurements of ice thickness, subglacial topography, basal hydrology, and internal layers in the ice. The survey region stands out as one of the major data gaps in BEDMAP II. In addition to the radar data, new laser data will be collected, giving ice sheet heights at an accuracy level of 5-10 cm. These data will help validate and augment satellite data and will also investigate subglacial lakes suggested by remotely sensed surface height changes.

For geodesy, the main focus will be to provide new high-resolution gravity data for global gravity field models and to supplement satellite missions (GOCE).  DTU-Space has led a similar project in the Arctic, where gravity data were compiled from vast, formerly secret holdings of Russia and the US, as well as all available other data, under a working group “Arctic Gravity Project” of the International Association of Geodesy. It has for a long time been the goal of geodesy also to complete the southern gravity void in Antarctica. This is critical for supplementing the ESA gravity satellite GOCE (Global Ocean Circulation Explorer), which due to orbit inclination suffer from polar coverage gaps.

New subglacial topography of the Recovery Glacier catchment from the ICEGRAV 2013 survey.

ICEGRAV 2013 international partners include:

DTU UK B1 RGB

rf1

Rene Forsberg PI Technical University Denmark (DTU)

AO

Arne Olesen Gravity specialist Technical University Denmark (DTU)

Instituto Antártico Argentino

Marta Ghidella PI Instituto Antártico Argentino (IAA)

Andrés Zakrajsek Geodetic specialist Instituto Antártico Argentino (IAA)

Norwegian Polar Institute

Peter Leopold DSC_7064 Kenny

Kenny Matsuoka PI Norwegian Polar Institute (NPI)

Jack Kohler Norwegian Polar Institute (NPI)

Anja Diez Norwegian Polar Institute (NPI)