Open AccessPotential groundwater and heterogeneous heat source contributions to ice sheet dynamics in critical submarine basins of E ast A ntarctica
Author(s) -
Gooch Brad T.,
Young Duncan A.,
Blankenship Donald D.
Publication year - 2016
Publication title -
geochemistry, geophysics, geosystems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.928
H-Index - 136
ISSN - 1525-2027
DOI - 10.1002/2015gc006117
Subject(s) - geology , advection , ice stream , groundwater flow , ice sheet , geomorphology , groundwater , sea ice growth processes , meltwater , aquifer , geothermal heating , heat flux , sea ice thickness , sea ice , arctic ice pack , geophysics , heat transfer , cryosphere , oceanography , geothermal gradient , glacier , geothermal energy , mechanics , geotechnical engineering , physics , thermodynamics
We present the results of two numerical models describing contributions of groundwater and heterogeneous heat sources to ice dynamics directly relevant to basal processes in East Antarctica. A two‐phase, one‐dimensional hydrothermal model demonstrates the importance of groundwater flow in vertical heat flux advection near the ice‐bed interface. Typical, conservative vertical components of groundwater volume fluxes (from either topographical gradients or vertically channeled flow) on the order of ±1–10 mm/yr can alter vertical heat flux by ±50–500 mW/m 2 given parameters typical for the interior of East Antarctica. This heat flux has the potential to produce considerable volumes of meltwater depending on basin geometry and geothermal heat production. A one‐dimensional hydromechanical model demonstrates that groundwater is mainly recharged into saturated, partially poroelastic (i.e., vertical stress only; not coupled to a deformation equation) sedimentary aquifers during ice advance. During ice retreat, groundwater discharges into the ice‐bed interface, which may contribute to water budgets on the order of 0.1–1 mm/yr. We also present an estimated map of potentially heterogeneous heat flow provinces using radiogenic heat production data from East Antarctica and southern Australia, calculated sedimentary basin depths, and radar‐derived bed roughness. These are overlaid together to delineate the areas of greatest potential effect from these modeled processes on the ice sheet dynamics of the East Antarctic Ice Sheet.