.gif)
Victoria University Antarctic Research Expedition Science and Logistics Reports 1972-73: VUWAE 17
SCIENTIFIC ACHIEVEMENTS
SCIENTIFIC ACHIEVEMENTS
VUWAE 17A
- Reconnaissance mapping and sampling of McMurdo Volcanics at:
- Cape Evans
- Dellbridge Islands
- Turks Head and Tryggve Point
- Cape Royds
- Mt. Erebus
- Mt. Melbourne
- Lyons (1973) has summarized the work at Mt. Melbourne and Mt. Erebus.
- Detailed geological mapping of Rainbow Ridge, Brown Peninsula.
- Visits to the summit of Mt. Erebus in January 1972 (Askin et al., 1972); December 1972 to January 1973; and February 1973 has helped in gaining an understanding of the present volcanic activity of Mt. Erebus.
- A detailed report (Kyle and Treves, 1973; Treves and Kyle, 1973) on DVDP holes 1 and 2 is in preparation.
REFERENCES
Askin, R.A., Barrett, P.J., Kyle, P.R., and Laird, M.G. 1972. Immediate report of Victoria University of Wellington Antarctic Expedition 1971-72. Wellington, N.Z.
Lyon, G.L. 1973. Preliminary report on the Expedition to Mounts Melbourne and Erebus. Institute of Nuclear Sciences Report No. 118. 17 pp.
Kyle, P.R. and Treves, S.B. 1973. The geology of Hut Point Peninsula, Ross Island, Antarctica. Dry Valley Drilling Project Bull. 2 (in prep.).
Treves, S.B. and Kyle, P.R. 1973. The geology of Dry Valley Drilling Project holes 1 and 2. Dry Valley Drilling Project Bull. 2 (in prep.).
VUWAE 17B - PARTS 1, 2
-
Detailed and systematic sampling of salt deposits was performed at: Capes Evans, Royds and Bird, the Dellbridge Islands, Hut Point Peninsula, Mt. Erebus (above the contour approximately 400 m below the summit), Pearse Valley, Lake Bonney area, and the Upper Wright Valley, More general sampling was performed at: Cape Barne, Turks Head, Tryggve Point, Taylor Dry Valley, New Harbour, Marble Point, Lake Vanda area, and the Lower Wright Valley.
Mt. Erebus, Pearse Valley, Cape Bird and probably the Dellbridge Islands - Turks Head area, have never been previously sampled for salts.
Samples were also collected at Shapeless Mountain by Crump and Blackwood, and at Mt. Melbourne and various areas on the middle slopes of Mt. Erebus by Kyle.
- The Salt Map of the McMurdo Sound area, commenced by Johnson in 1969-70, can now be extended to these new areas and also to the Wright Valley and Marble Point area.
- The hypotheses advanced during a study of salts in the McMurdo Sound area for Keys' M.Sc. thesis were examined. The validity of these was found to be good. The directional bias of salt accumulation was observed and the accumulation was found to be continuing. The atmospheric relative humidity was shown to increase with altitude in the Dry Valleys and the related but previously hypothetical regions of accumulation of different salts were discovered. The area where NaCl becomes dominant over Na2 SO4 was found to be near Cape Bernacchi. On the eastern coast this area was found in November 1969 to be near Cape Barne. It does not appear to have changed appreciably in November 1972.
- More specific achievements include the detailed investigation of two large and previously unreported sait hollows, one in the Pearse Valley and one near the Upper Wright Glacier. The Taylor Red Deposit was also closely investigated. Although this was thought to be unique, another apparently chemically similar, more extensive but less developed deposit was discovered at the snout of the Upper Wright Glacier.
- Many unusual crystalline structures and salts were collected and it is thought that among these are the "controversial" nitrate and bicarbonate salts.
-
Daily samples of the Onyx River were taken during the flow period (December 13 to February 6), These are being analysed for Na, K, Ca, Mg, Sr, in order to obtain an estimate of the annual ion flow into Lake Vanda.
Chemical analyses and crystallographic examination will be carried out on over 400 samples collected and the data will be published in New Zealand and overseas journals.
References
Black, R.F., Jackson, M.L., and Berg, T.E. (1965). 'Saline Discharge from the Taylor Glacier, Victoria Land, Antarctica', J. Geol. 73(1), 175-81.
Johannesson, J.K. and Gibson, G.W. (1962). 'Nitrate and Iodate in Antarctic Salt Deposits', Nat. (Lond.), 194 (4828), 567-8,
Johnson, J.H. and Keys, J.R. (In Press). 'Aragonite and Nacolite from Antarctica', Nat. (Lond.).
Keys, J.R. (1972). 'A Study of Salt Origin, Distribution, and Weathering Processes in the McMurdo Sound Region, South Victoria Land, Antarctica', M.Sc. Thesis, Victoria University of Wellington.
Wilson, A.T. and House, D.A. (1965). 'Fixation of Nitrogen by Aurora and its Contribution to the Nitrogen Balance of the Earth', Nat. (Lond.), 225, 793-4.
VUWAE 17C
A detailed study and sampling of the Mawson volcano breccia was carried out at Shapeless Mountain and on neighbouring Mistake Peak. The lithology of the breccia varied quite considerably, both in clast and matrix composition, and sometimes this could be directly related to underlying or included rock types, Dolerite intrusions, sometimes partly or wholly brecciated themselves, showed no gradation into the main breccia.
Petrographic examination, chemical analysis, and possibly dating, will be carried out on the material sampled.
VUWAE 17D
Numerous minor problems were encountered with some of the equipment for measuring the velocity of convection within Lake Vanda. The time taken correcting these necessitated curtailing some of the original objectives. However temperature, density and velocity measurements were made at two stations. Analysis of the data is still continuing at the time of writing. Preliminary investigations of the temperature and density measurements suggest that the thermal structure of the lake has developed very little over recent years. Velocity measurements have yet to be reduced but an unusual sinusoidal variation was recorded in the upper part of a large 25 metre dense layer which occurs towards the base of the lake.