abstract
The detailed mapping of the Straumsnutane Formation occurring on the Ahlmannryggen, western Dronning Maud Land, Antarctica, was undertaken during 1968 by the Ninth South African National Antarctic Expedition. This Formation has a total thickness of 860 m in the Straumsnutane, the type area, and may be divided tentatively into four conformable members, viz a lower member comprising 260 m of lava characterized by very large amygdales; a transitional member of 100 m thickness; a middle member consisting of 1 00 m of alternating amygdaloidal and non –amygdaloidal lava; and an upper member comprising 400 m of predominantly amygdaloidal lava, with subordinate dense lava and characteristic pillow structures. Minor intercalated sediments occur in the upper half of this member.