Event NameVictoria University of Wellington (VUWAE) 16AAbstract
An evaluation of the use of a portable coring drill for obtaining oriented paleomagnetic samples was undertaken. In all 19 sites were sampled using the drill at Cape Crozier, Cape Bird, Cape Barne and Hut Point Peninsula. Oriented block samples were also collected for paleomagnetic determinations at Cape Barne, Cape Crozier and Fang Glacier.
Detailed mapping and sampling of the McMurdo Volcanic Group at Mt Morning while the following localities around McMurdo Sound were visited and sampled: Inaccessible Island, Mt Cis, Summit Crater Mt Erebus, Fang Ridge, Mt Erebus, Abbotts Peak and areas at Cape Crozier. Petrographic and detailed chemistry will be carried out on material collected.
Of major importance was the discovery of fossils in the Bowers Group at the head of the Mariner Glacier 12-15km south-west of Mt McCarthy. These are the first body of fossils to be discovered in the Bowers Group, and the first (apart from some plant remains) to be found in Northern Victoria Land. The fossils consist mainly of brachiopods and trilobites, and preliminary studies suggests late Cambrian (approx. 500 million yrs) age for the upper part of the Bowers Group. The sequence in which the fossils were found is 1700m thick, consisting of fissile shale in the lower half, passing gradationally upwards into sandstones above.
These probably represent shallow marine deposits. The upper 360 of the marine sequence consists mainly of red sandstones, with rare fossils, trilobites tracks, and mud cracks, suggesting very shallow marine, possible inter-tidal conditions. Above the red beds quarzitic sandstone and conglomerate of probably fluvatile origin occur. This is correlated with the Camp Ridge Quartzite seen further north.
A further important discovery was the presence of Bowers Group rocks in the north part of Evans Névé, lying far to the west of previously known occurrences. It is possible that unvisited nunataks lying further west may also be composed of Bowers Group sediments. The previously unvisited southern end of the Salamander Range was found to consist not only of granite, as previous maps have shown, but also dolerite. An isolated exposure of conglomerate of unknown affinities was also mapped.
Geological mapping and sampling of the McMurdo Volcanic Group was undertaken at the Pleiades where a basalt-trachyte-basalt eruptive sequence was recognised. Geological data for compiling the 1:250 000 Freyberg Mountain map were collected.