Fig. 1: Structural setting of the Mount Erebus magmatic system.
Site map showing impedance phase-tensor ellipses at the MT sounding locations over Mount Erebus and Ross Island during three field seasons; see text for color and shape designations. Coordinate ticks denote both UTM Zone 58S (singles) and latitude–longitude (doubles). Note the warm-colored ellipse region southwest of Mount Erebus indicating conductive volumes in the 0–7 km depth range approximately (Supplementary Information). Hypothesized Erebus fault zone contains principal low-resistivity structure resolved through the crust. The lower right inset shows regional structural setting15,16,17, including the Ross Fault (green) in the accommodation zone of the terminus of the Terror Rift (TR) and Discovery graben (DG). Other symbols include Southern Victoria Land basin (SVL) and Discovery accommodation zone (D--A--Z). Yellow dashed lines represent other antithetic shear zones separating Dry Valleys block (DVB), Royal Society block (RSB), and Skelton block (SB). Volcano mounts include Bird (BR), Terror (TR), Terra Nova (TN), Erebus (ER), Hut Point (HP) Morning (MR), and Discovery (DS). Upper right inset places location of lower right view within Antarctica. The upper right orientation is ~180o rotated from the main and lower panels.
