Abstract:
The first study of the physics and chemistry of Lake Vanda and the geology of the surrounding area were investigated in the 1961-1962 field season. Twelve holes were drilled at 1000ft intervals along two lines, one along the length of the lake and the other across its widest part. Water temperatures were measured at 5 ft intervals. Density and chemical composition were measured at 5ft intervals ... through one hole in the central part of the lake. The temperature gradient in the soft mud at the lake bottom was also measured near the centre of the lake by driving in a geothermal gradient probe. Bolometer measurements of the solar energy flux were made through five holes under a variety of cloud conditions and at depth up to 50ft below water level. The heat balance of the lake presented interesting problems pertaining to the source of heat. There are five possible sources including: i) Biological activity within or at the base of the lake, ii) chemical heating, iii) hot springs in the lake bottom, iv) abnormally high geothermal gradient under lake and v) radiant energy from the sun penetrating into the lake and being absorbed. Each source was investigated in turn. While making measurements on the heat balance of the lake, equipment was frequently suspended from nylon monofilaments. If these lines were allowed to remain in position for 24 hours, a red material was found to accumulate on that part of the line that had been between 55ft and 125ft. This material froze as it came into the air and accumulated at the eyelet of the winding reel. A sample of this material was examined by the biological staff at McMurdo station and was identified as being principally Phormidium with a few Chroocuccus and a few Anabaena algae.
Quality
All data relating to this study can be found in the publications. Within the logistics report submitted to Antarctica New Zealand two table contain the following data: Table 1: Temperature vs Depth profiles for the lower part of Lake Vanda. Table 2: The temperature gradient below 160ft in Lake Vanda and solar heating mechanism.
