Table Mountain: (Figure 5)

The southern edge of the Sirius platform resembles the distal side of a lateral moraine which could explain why it is the southern limit of Sirius at Table Mountain. It may mark the edge of an outlet glacier (ancestral Ferrar or Tedrow) that issued from the East Antarctic Ice Sheet to the southwest, sweeping eastward around an intrusive knob and over the north slope of Table.

Below TM-1 (Dickinson 1997) is a basin carved into Terra Cotta siltstone with Sirius exposed in its north side (not drilled in 1996 but studied by James Goff). This appears to be an old cirque, complete with recessional moraines resting on its floor and even over its northern edge. It could be that the ancestral outlet glacier overrode or pushed against the cirque glacier which prevented the deposition of Sirius in the basin proper.