Uplift of the Antarctic Continent in Elastic Deformation

概要

論文の詳細を見る
The uplift of the shorelines in snow-free areas of the Antarctic Continent is estimated to be 20-30m and the retreat of the ice sheet to be 10-100km. This paper tries a theoretical interpretation of this uplift in terms of static deformation of an elastic semi-infinite medium or multi-layered medium due to the diminution of the load on the surface. As the forms of load function, which can be regarded as almost the same as the form of the ice sheet, two types of functions are considered as follows : Case I where constant pressure acts on the surface within a circular area, and Case II where pressure varies with the radius of a circular. As the crust and mantle structures, three models (Semi-infinite A, Semi-infinite B, and CANSD) are considered. The uplift is calculated by the difference in vertical displacements between the initial and the final states of the ice sheet. The initial thickness and the radius of ice sheet are denoted by H and a, and the decreases in thickness and radius are denoted by ⊿H and ⊿a, respectively. The observed uplift can be explained by the following either set of H and ⊿H with fixed a (=1700km) and ⊿a (=50km) for the Semi-infinite B and the CANSD models; for Case I, H=2.0km and ⊿H=0-0.1km, and for Case II, H=4.0km and ⊿H=0-0.1km. Reasonable values of H and ⊿H are not obtained for the Semi-infinite A model for both Cases I and II.
国立極地研究所の論文