THE GREAT FAULTS 
437 
South Victoria Land. Probably about the middle of 
Tertiary times that part of the crust was subjected to 
further shrinkage stress of an even kind, which ultimately 
resulted in a series of great breaks or faults along the 
present coast-line. On the upthrow side of the fault the 
land was slowly raised into the present plateau, while on 
the downthrow side the land was depressed below sea 
level, and now forms the Ross Sea and the sea bottom 
below the Great Ice Barrier. Simultaneously with, and 
probably as an effect of this faulting, there occurred a 
great outburst of volcanic energy along the line of break. 
At many points volcanoes were formed, the chief centres 
being the Ross Archipelago, the Cape Adare Peninsula, 
and the Balleny Islands. This outburst is now just 
dying out, only two volcanoes being still active — Mt. 
Erebus on Ross Island, and Sturge Island in the Balleny 
Group. No recent deposits having been found, the later 
pages of the history of this area must come from its 
physiography, and cannot be treated of here. 
For the work upon which this history is founded our 
thanks are due to the geologists of the various Antarctic 
Expeditions, chiefly Mr. H. T. Ferrar, of the National 
Antarctic Expedition, and Professor T. W. Edgeworth 
David and Mr. R. E. Priestley, of the British Antarctic 
Expedition, 1907-9. The 35 lbs. of specimens brought 
back by the Polar Party from Mt. Buckley contain impres- 
sions of fossil plants of late Palaeozoic age, some of which 
a cursory inspection identifies as occurring in other parts 
of the world. When fully examined, they will assuredly 
prove to be of the highest geological importance. 
