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Hallett Volcanic Province

The volcanoes along the Ross-Sea coast of northern Victoria Land collectively form the Hallett volcanic province in Fig. 16.35. This province includes the Adare, Hallett, and Daniell peninsulas, and Coulman Island. Volcanic rocks of Cenozoic age also occur on the Possession Islands and at a few vents on the mainland west of the major volcanic complexes named above (McIntosh and Kyle 1990a). [Pg.550]


Fig. 16.35 The Hallett volcanic province consists of five regions along the Ross-Sea coast of northern Victoria Land ... Fig. 16.35 The Hallett volcanic province consists of five regions along the Ross-Sea coast of northern Victoria Land ...
The total-alkali and silica concentrations of three rock samples from the Adare Peninsula are classified in Fig. 16.36 as a basanite, a phonolite, and a trachyte (McIntosh and Kyle 1990b). Additional chemical analyses by Hamilton (1972), Smith (1964), David et al. (1896), and unpublished data by P.R. Kyle and W.C. McIntosh demonstrate a continuous spectrum of rock types on the Adare Peninsula from SiO = 42% to 67%. The presence of large volumes of palagonitic tuff breccias and pillow breccias on the Adare Peninsula and elsewhere in the Hallett volcanic province led Hamilton (1972) to conclude that these rocks were erupted through ice at a time when the East Antarctic ice sheet had expanded. This interpretation was supported by the presence of abundant glacial erratics on the northern end of the Adare Peninsula (Priestley 1923). [Pg.551]

Fig. 16.36 The volcanic rocks in the Hallett volcanic province range from basanites to phonolites and trachytes. The principal volcanic centers represented on this diagram are Cape Adare, Cape Hallett, Cape Daniell, Coulman Island, and the Possession Islands. The rock types are identified by the letters in each field Bn = basanite, Tp = tephrite, Ptp = phonotephrite, Tpp =... Fig. 16.36 The volcanic rocks in the Hallett volcanic province range from basanites to phonolites and trachytes. The principal volcanic centers represented on this diagram are Cape Adare, Cape Hallett, Cape Daniell, Coulman Island, and the Possession Islands. The rock types are identified by the letters in each field Bn = basanite, Tp = tephrite, Ptp = phonotephrite, Tpp =...
The volcanic rocks on Possession and Foyn islands in Fig. 16.36 are basanites and tephrites in the form of lava flows, volcanic bombs, andmegapillows. McIntosh and Kyle (19900 commented that the rocks of the Possession Islands are least altered of all the rocks in the Hallett volcanic province that have been analyzed. [Pg.554]

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. [Pg.556]

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. [Pg.558]

McIntosh WC, Kyle PR (1990a) Hallett volcanic province Summary. In LeMasurier WE, Thomson JW (eds) Volcanoes of the Antarctic Plate and Southern Oceans. Antarctic Research Series, vol. 48. American Geophysical Union,... [Pg.569]

The volcanoes of the Transantarctic Mountains occur between Cape Hallett in northern Victoria Land and Mount Early (87°04 S, 153°46 W), which is located only 300 km from the South Pole. The volcanic mountains and cinder cones in the Transantarctic Mountains define the McMurdo Volcanic Province which is subdivided into four regions (Kyle 1990). These volcanoes were active in Late Tertiary time starting less than 25 million years ago and continuing to the present as in the case of Mount Erebus. All of them have extruded silica-undersaturated and alkali-rich lavas in marked contrast to the Ferrar Dolerite and Kirkpatrick Basalts of Middle Jurassic age both of which consist largely of silica-saturated tholeiites. These two suites of volcanic rocks are products of quite different petrogenetic processes that nevertheless occurred at different times in the lithospheric mantle underlying the Transantarctic Mountains. The petrogenesis of these different suites of volcanic rocks is the subject of Chapter 12 (Kirkpatrick Basalt) and Chapter 13 (Ferrar Dolerite), and Chapter 16 (Cenozoic Volcanoes). [Pg.44]

Fig. 16.5 Whole-rock K-Ar dates of the McMurdo Volcanics of the Erebus, Hallett, and Melbourne volcanic provinces form an unbroken sequence from the Holocene (0 Ma) to the middle Miocene (10 Ma). The oldest date is 18.0 0.7 Ma (early Miocene) followed by 15.4 0.5, 13.8 0.2, and 13.2 0.4 Ma, all of which are in the Miocene. The pattern of variation of K-Ar dates indicates that the volcanic activity started during the early Miocene and continued without interruption to the present. Early-formed volcanic rocks are removed by erosion and may also be covered by younger flows which explains why the frequency of K/Ar dates decreases with the increasing age of the rocks (Data from Armstrong (1978), Forbes et al. (1974), and Fleck etal. (1972))... Fig. 16.5 Whole-rock K-Ar dates of the McMurdo Volcanics of the Erebus, Hallett, and Melbourne volcanic provinces form an unbroken sequence from the Holocene (0 Ma) to the middle Miocene (10 Ma). The oldest date is 18.0 0.7 Ma (early Miocene) followed by 15.4 0.5, 13.8 0.2, and 13.2 0.4 Ma, all of which are in the Miocene. The pattern of variation of K-Ar dates indicates that the volcanic activity started during the early Miocene and continued without interruption to the present. Early-formed volcanic rocks are removed by erosion and may also be covered by younger flows which explains why the frequency of K/Ar dates decreases with the increasing age of the rocks (Data from Armstrong (1978), Forbes et al. (1974), and Fleck etal. (1972))...
Armstrong (1978) reported two K-Ar dates of 5.49 0.12 Ma and 6.6 0.4 Ma (late Miocene) for rocks of the Hallett Peninsula. Three samples of basalt Irom Cape Hallett analyzed by Jones and Walker (1972) have Sr/ Sr ratios that range from 0.7037 to 0.7054 and are consistent with the Sr/ Sr ratios of the volcanic rocks of the Erebus and Melbourne volcanic provinces. [Pg.551]


See other pages where Hallett Volcanic Province is mentioned: [Pg.519]    [Pg.527]    [Pg.550]    [Pg.551]    [Pg.553]    [Pg.555]    [Pg.519]    [Pg.527]    [Pg.550]    [Pg.551]    [Pg.553]    [Pg.555]   


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14.5 Hallett Volcanic Province, NVL chemical classification

Hallett

Province

Volcanic

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