Ellsworth-Whitmore Mountains Crustal Block, Western Antarctica: New paleomagnetic results and their tectonic significance ...

• Main Authors: Grunow, A. M., Dalziel, I. W. D., Kent, Dennis V.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Columbia University 1987
• Subjects: Geology, Stratigraphic; Geophysics; FOS: Earth and related environmental sciences; Antarctic; The Antarctic; Antarctic Peninsula; East Antarctica; Tilting; Whitmore Mountains; Antarc*
• Online Access: https://dx.doi.org/10.7916/d8cv4gw1; https://academiccommons.columbia.edu/doi/10.7916/D8CV4GW1

Preliminary paleomagnetic study of granitic and sedimentary rocks from the Ellsworth-Whitmore Mountains crustal block (EVH), Vest Antarctica, leads to the following conclusions: (1) The EVH has a paleogole for the Middle Jurassic located at 235°E, 41°S, (α₉₅ = 5.3, N = 8 sites) assuming that no widespread regional tilting has occurred since the magnetization measured was acquired. A Middle Jurassic paleolatitude of 47°S is indicated for the sites and precludes an original location for the EVH block south of the Antarctic Peninsula crustal block (AP). (2) This pole is not significantly different from the previously published Middle Jurassic paleopole obtained from rocks of the northern Antarctic Peninsula. The combined AP-EVH paleopole, compared to the Middle Jurassic mean paleopole obtained from igneous rocks of the Ferrar Supergroup in East Antarctica, suggests about 15° tectonic clockwise rotation of the AP and EVH. Since the AP and EVH poles coincide, these two crustal blocks may have moved as one unit ...