The tectonic evolution of Antarctica

• Main Author: Hamer, Richard Daniel
• Format: Master Thesis
• Language: English
• Published: University of Cambridge 1977
• Subjects: West Antarctica; Pacific; Antarc*; Antarctica
• Online Access: https://www.repository.cam.ac.uk/handle/1810/295127; https://doi.org/10.17863/CAM.42197

Five tectonic provinces; three volcanic provinces (each characteristic of a particular set of tectonic conditions) and a Precambrian shield, are outlined and described, in an attempt to illustrate the tectonic evolution of Antarctica. Evidence is presented for at least three structural stages in the development of the Precambrian shield, though it is not as yet possible to delineate individual tectonic provinces within the shield area. From the late Proterozoic until the early Mesozoic, a series of tectonic provinces were successively stabilised and accreted onto the Pacific margin of the Precambrian shield. In the Mesozoic however, this unstable margin broke up into a number of blocks, as a result of differential movements between East and west Antarctica, associated with the fragmentation of Gondwanaland. Block tectonics, rifting and the development of faultbounded marginal basins, were accompanied by alkali volcanism in the late Cenozoic. This activity continues at the present. The proposed scheme is also viewed in the wider context of Gondwanaland and plate tectonics. Although the justification for long distance correlation of individual tectonic regions is called into question, four stages are illustrated in the evolution of the present Southern Hemisphere.