FROM THE MAINLAND OF SOUTH VICTORIA LAND 231 



Efidotised Granite from the same locality. This has suffered crushing and shows 

 bundant greenish -grey epidote along the crush-lines. The ferromagnesian con- 

 stituents are partly chloritised. 



Another example of a crushed granite is an even-grained light-coloured gneiss from 

 the moraine twenty miles south-east of Mount Larsen. 



This is a schistose granular rock consisting of quartz, orthoclase, plagioclase, a little 

 light-coloured yellow and green biotite, and grains of ilmenite. Granulation is far 

 advanced. 



Another specimen from the same moraine resembles this in every respect but that 

 it appears to represent a more advanced condition of dynamometamorphism. Granu- 

 lation is complete. Accessory minerals are abundant, including poikiloblastic pink 

 garnet, light yellow zircon, and rare apatite and titaniferous magnetite. 



An Erratic Specimen from Marble Point, five miles North of Cape Bernacchi, is a 

 granite metamorphised by solutions which have passed along a vein now occupied by 

 reef quartz. The ferromagnesian minerals have been leached out in proximity to the 

 vein and the felspars completely saussuritised. Grains of leucoxene are abundant. The 

 quartz shows shadowy extinction. Away from the vein biotite appears, this is pleo- 

 chroic, colourless to orange-brown. The vein contains quartz with some pyrites. 



Several gneissic specimens from the Beardmore Glacier are either meta -granites 

 or meta-arkoses of the composition of granite. Obviously it is impossible to distinguish 

 between these in the case of loose specimens. 



METAMORPHISM OF THE BASIC IGNEOUS ROCKS 



No cases of this kind were met with in situ, unless the case of the basic inclusions 

 in the granite of Depot Island is regarded as such. Ferrar refers to a metamorphism 

 of the dolerites by intrusion of the pink granites. It may be that some of the amphi- 

 bolite erratics referred to elsewhere in the text have originated in this manner. Among 

 these amphibolites there is a general development of uralite and saussuritisation of the 

 felspars. 



Other metamorphic rocks of igneous origin are : A banded gneiss and a mica schist 

 with large poikiloblastic felspars, both from Dry Valley ; also a sphene-bearing 

 actinolite gneiss from the upper glacial moraine, Ferrar Glacier. 



METAMORPHOSED SEDIMENTS 



Ferrar has described an extensive calcareous sedimentary belt outcropping in a 

 nearly north and south direction along the foothills of the Admiralty Range and towards 

 Cape Bernacchi. This we found to continue almost to Dunlop Island. At Cape 

 Bernacchi is a thick series of contorted and brecciated sedimentary rocks, prominent 

 amongst which is a saccharoidal marble. Zones of pseudo pebbles are evidence of 

 dynamic forces having been involved. Mineral solutions have risen in fissures inter- 

 secting the outcrops in all directions, and have effected powerful changes in the adjacent 

 strata. 



Amongst these are quartz veins with occasional pyrites and quartz -felspar -muscovite 

 veins with abundant black tourmaline. The coarse saccharoidal marble is the rock 

 of chief interest. It contains a small percentage of graphite particles and crystals of 

 iron pyrites. Several crystals of copper pyrites were also noted. Where slight im- 

 purities occur, bands containing much epidote are met. A reddish biotite is also 

 frequently developed. Other patches contain red garnet. 



At Marble Point, five miles to the north of Cape Bernacchi, a similar outcrop of 

 marble occurs. Associated with this is a fine mica-granulite, also pyrite- and epidote- 



