Speaking about Heat Flow, Ice Fusion and Temperature Alterations

World Multidisciplinary Earth Sciences Symposium

Duque, Maria Rosa^1

Departamento de Física, ECT, Universidade de Évora, Rua Romão Ramalho 59, Évora, Portugal^1

关键词: Antarctic Peninsula;    Ice thickness;    Measured values;    Minimum value;    Rift systems;    Tectonic activity;    Temperature values;    Volcanic region;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/221/1/012060/pdf
DOI  :  10.1088/1755-1315/221/1/012060

来源: IOP

【 摘 要 】

Heat flow density measurements are difficult to obtain in Antarctica and Greenland due to climate and ice thickness in those regions. The works published about that subject shows that spatial distribution of the heat flux values is highly heterogeneous. Maximum and minimum values of heat flux vary with different authors and method used, but all of them say that East Antarctic is characterized by low heat flux values (45-85 mW m-2) with the lowest values found especially in the central part. The values obtained in West Antarctic (65-180 mW m-2) and in the Antarctic Peninsula (maximum of 170 mW m-2). In the work whose data is used high values were obtained in the West Antarctic Rift system (maximum value of 130 mW m-2). Some local geothermal anomalies have been reported such as Lake Wilhams (285 mW m-2) or Siple Dome (69 mW m-2). Elevated heat flux values are obtained in volcanic regions and in regions with relatively recent tectonic activity, in West Antarctic. The east Antarctic is characterized by low values, however the Coastal part of Queen Mary Land, the Lambert Rift and Victoria Land, show higher values, suggesting Cenozoic processes in the region, including volcanism or extension. Ice fusion occurs near the base of the ice sheet. In order to study these fact relations between heat flux, bed, thickness and ice altitude were studied. In regions with bottom of the ice below sea level ice melting of the ice occurs. The amount of ice obtained is under the measured value. The effect of sea water interacting with ice must be considered. Temperature values alterations at the surface may be found in the ice, including alterations due to last glaciations must they are not the cause of ice melting.