Magmatic and tectonic patterns over the Northern Victoria Land sector of the Transantarctic Mountains from new aeromagnetic imaging

New aeromagnetic data image the extent and spatial distribution of Cenozoic magmatism and older basement features over the Admiralty Block of the Transantarctic Mountains. Digital enhancement techniques image magmatic and tectonic features spanning in age from the Cambrian to the Neogene. Magnetic lineaments trace major fault zones, including NNW to NNE trending transtensional fault systems that appear to control the emplacement of Neogene age McMurdo volcanics. These faults represent splays from a major NW-SE oriented Cenozoic strike-slip fault belt, which reactivated the inherited early Paleozoic structural architecture. NE-SW oriented magnetic lineaments are also typical of the Admiralty Block and reflect post-Miocene age extensional faults. To re-investigate controversial relationships between strike-slip faulting, rifting, and Cenozoic magmatism, we combined the new aeromagnetic data with previous datasets over the Transantarctic Mountains and Ross Sea Rift. Two key observations c...