Crustal Structure of Antarctica

The results summarized by Bentley (1983) in Eig. 15.10 are based on gravity anomalies pnblished by Groushinsky and Sazhina (1982). The diagram indicates that the thickness of the subglacial crust of 

Antarctica increases stepwise from about 20 to 40 km in West Antarctica, to 40-50km under the Transantarctic Mountains (TAM), and to more than 60 km under the Gamburtsev Mountains (GM). The principal exceptions in West Antarctica are the Ellsworth-Whitmore Mountains (EWM) and Marie Byrd Land (MBL) where the thickness of the crust rises to more than 40 km. The crustal thickness under the Transantarctic Mountains rises abruptly from 35 to about 45 km which suggests that this boundary is a fault zone or crustal suture. 

The profile of the crustal thickness of parts of West and East Antarctica in Fig. 15.11 indicates the complementary depth to the Mohorovicic Discontinuity (Moho) and illustrates the increase of the crustal thickness at the boundary between West and East Antarctica. The structure of the crust of Antarctica was also investigated by Dewart and Toksoz (1965), Jankowski and Drewry (1981), Kurinin and Grikurov (1982), and by 

Kadmina et al. (1983). In spite of the insights gained by these and related studies, several important questions remain  

How was West Antarctica assembled from blocks of continental crust following the break-up of Gondwana  

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Bentley CR (1983) Crustal structure of Antarctica from geophysical evidence a review. In Oliver RL, James PR, Jago JB (eds) Antarctic earth science. Australian Academy of Science, Canberra, ACT, Australia, pp 491-497 Bentley CR, Robertson JD (1982) Isostatic gravity anomalies in West Antarctica. In Craddock C (ed) Antarctic geoscience. University of Wisconsin Press, Madison, Wl, pp 949-954 Bentley CR, Robertson JD, Greischar LL (1982) Isostatic gravity anomalies on the Ross Ice Shelf. In Craddock C (ed) Antarctic geoscience. University of Wisconsin Press, Madison, Wl, pp 1077-1081... 

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