Balleny Islands

The Balleny Islands were discovered by J. Balleny on February 9,1839. The coasts of the islands consist of steep cliffs and the interiors are covered by ice caps. Quartermain (1964) reported that volcanoes were erupting on Buckle Islands in 1839 and 1899 but a survey of infrared radiation by Burge and Parker (1969) did not detect thermal anomalies on any of the islands. 

The Balleny Islands are frequently surrounded by pack ice until the end of the summer and, because of their remote location, they have been visited only rarely and no systematic geological field work has been done there. 

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The Balleny Islands in Fig. 16.39 are located in the southern Pacific Ocean about 250 km north of the Pennell Coast of northern Victoria Land between 66°16 to 67 38 S and 162 15 to 164°44 E. They form a Unear chain of volcanic islands between Erast Antarctica and Australia and resemble in this regard... 

Scott Island is a large submerged free-standing volcanic mountain that rises from the seafloor to a height of about 100 m above the surface of the ocean (Womer and Orsi 1992). It is located at 67°30 S and 180°00 about 500 km east of the Balleny Islands. 

Fig. 16.39 The Balleny Islands are located about 250 km north of the Pennell Coast of northern Victoria Land. They are the summits of volcanoes on a submarine ridge that is aligned with the Tasman Fracture Zone located north of the Pacific-Antarctic sea-floor spreading ridge. Volcanic eruptions on Buckle Island were reported in 1839 and 1899. However, an infrared survey published in 1969 did not detect any thermal anomalies (Burge tuid Parker 1969) (Adapted from Wright and Kyle (1990a) in LeMasurier and Thomson (1990))...

The volcanic activity of the Balleny Islands and of Scott Island is related to their location between East Antarctica and Australia (Duncan and McDougall 1989 Lanyon et al. 1993, 1995). Partly for that reason, the Sr/ Sr ratios of the volcanic rocks on these islands are lower than the Sr/ Sr ratios of lavas on the mainland of northern Victoria Land. Hart and Kyle (1993) reported that the volcanic rocks of the Melbourne and Hallett volcanic provinces have higher Sr/ Sr ratios than the lavas on the off-shore islands including Franklin, Coalman, Possession, Scott, and the Balleny islands. 

The HIMU component typically has a high 206pb/204pb j. bo between 20.5 and 21.5 and a low Sr/ Sr ratio between 0.7025 and 0.7030 which places it in Fig. 16.42 on an extension of the hyperbolic Sr-Pb isotopic mixing line loosely defined by the Cenozoic volcanic rocks of the Hallett volcanic province. The volcanic rocks on the Balleny Islands and on Scott and Peter I islands have isotopic compositions of strontium and lead that overlap those of the Hallett volcanic province. However, the Sr/ Sr ratios of the Balleny/ Scott islands are low (0.7025-0.7030), whereas those of Peter I Island (0.7038-0.7040) are normal for oceanic island basalts. 

We now shift our attention from the Balleny Islands to the head of the Scott Glacier in the Queen Maud Mountains (QMM) (Sections 2.2, 6.4, and 10.4.2)... 

Mawson D (1950) Basaltic lavas of the Balleny Islands. ANARE report. Trans Roy Soc Australia 73 223-231 McGibbon FM (1991) Geochemistry and petrology of ultramafic xenoliths of the Erebus Volcanic Province. In Thomson MRA, Crame JA, Thomson JW (eds) Geological evolution of Antarctica. Cambridge University Press, Cambridge, UK, pp 317-322... 

Quartermain LB (1964) The BaUeny Islands A descriptive and historical outline, compiled for use of the New Zealand Antarctic Research Expedition Balleny Islands Reconnaissance Party 1963-1964. Antarctic Div., New Zealand, D.S.I.R. Welhngton, New Zealand, pp 1-42 Radke L (1982) Sulphur and sulphate from Mr. Erebus. Nature 299 710-712... 

Wright AC, Kyle PR (1990a) Balleny Islands. In LeMasurier WE, Thomson JJ (eds) Volcanoes of the Antarctic Plate and Southern Oceans. Antarctic Research Series, voL 48. American Geophysical Union, Washington, DC, pp 449-450... 

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