Mount Melbourne is surrounded by a volcanic field consisting of 60 exposed volcanoes, which have the form of scoria cones and tuff rings with hyaloclastite deposits, lava flows and pillow lavas. Some of these volcanoes formed under ice. The volcanic field forms a peninsula which is separated by steep faults from the Transantarctic Mountains to the north. Among these volcanoes is Shield Nunatak southwest from Mount Melbourne, a subglacial volcano, now exposed, that may have formed during the latest Pleistocene. The Cape Washington ridge consists mostly of lava, including pillow lava, overlaid by scoria cones, and is the remnant of a shield volcano. Edmonson Point is another volcanic complex in the system that formed partly while interacting with glaciers and partly through phreatomagmatic activity. Other volcanoes in the field are Baker Rocks, Oscar Point and Random Hills. These volcanoes are aligned mainly in north-south direction and include both edifices that formed above and under ice, with palagonitized outcrops that expose dikes. Perfectly preserved scoria cones occur at Pinkard Table north of the volcanic field, while Harrow Peak is a heavily eroded lava plug. The total volume of volcanic rocks is about and their emplacement apparently altered the path of the Campbell Glacier.