Rb-Sr systematics

Briqueu, L. Lancelot, J. R. (1979). Rb-Sr systematics and crustal contamination models for calc-alkaline igneous rocks. Earth Planet. Sci. Letters, 43, 385-96. 

Lippolt, H. J., Schleicher, H. Raczek, I. (1983). Rb-Sr systematics of Permian volcanites in the Schwarzwald (SW Germany). Space of time between plutonism and late orogenic volcanism. Contribution of Mineralogy and Petrology, 84, 272-80. 

Vidal, Ph., Blais, S., Jahn, B. M., Capdevila, R. Tilton, G. R. 1980. U-Pb and Rb-Sr systematics of the Suomussalmi Archean greenstone belt. Eastern Finland. Geochimica et Cosmochimica Acta, 44, 2033-2044. 

Modal and Chemical Compositions and Rb-Sr Systematics of the Wyatt Formation, Scott-Glacier Area and Wisconsin Range, Transantarctic Mountains... 

Rb-Sr Systematics, Wyatt Formation, Scott-Glacier Area, Queen Maud Mountains (Faure, Unpubiished)... 

Rb-Sr Systematics of Felsic Pyroclastics of Unit G of the Leverett Formation,... 

The Wyatt Formation was initially assigned a Neoproterozoic date of 633 13 Ma (k = 1.39 x 10" year 0 based on the Rb-Sr systematics of four samples from Metavolcanic Mountain (Faure et al. 1968a Montigny and Faure 1969). This date was later restated as 630 14 Ma by Faure et al. (1968b). After analyzing additional samples, Faure et al. (1977) reported a date of 543 48 Ma (Early Cambrian) when the decay constant of Rb is taken to be A. = 1.42 x 10 year"h The analytical data of seven samples of the Wyatt Formation from Metavolcanic Mountain, the Cleveland Mesa, and the Wisconsin Plateau in Appendix 1.9.2.2 constrain a straight line in Fig. 7.12 which defines the time of crystallization of these rocks ... 

The crustal characteristics of the Jurassic doler-ites of Antarctica and Tasmania relate these rocks to each other and set them apart from Jurassic dolerite in southern Africa and Brazil. This point was emphasized by Compston et al. (1968) in a direct comparison of Rb-Sr systematics of Mesozoic basaltic rocks in southern Victoria Land, Tasmania, South Africa, and South America. In addition, these authors reported K-Ar dates for plagioclase and pyroxene from a pegmatoid in the Lake Vanda sill in Wright Valley of southern Victoria Land. The results indicated a Middle Jurassic age for the Ferrar Dolerite, in agreement with the age of the Tasmanian Dolerite and the K-Ar dates of the Wisanger Basalt on Kangaroo Island of South Australia reported later by McDougall and Wellman (1976). 

The Rb-Sr systematics of the sills on Roadend Nunatak (Appendix 13.6.3) are interpreted in Fig. 13.18 to determine the age of the two sills. Eight of nine whole-rock samples of the Peneplain sill loosely constrain a straight line that yields a date of 182 9 Ma and an initial "Sr/ Sr ratio of 0.71167 0.00014 (la). Ten whole-rock samples of the Basement sill have more scattered isotope ratios such that only six approach a straight line in Fig. 13.18. The date derivable from this line is 187 20 Ma and the initial Sr/ Sr ratio is 0.71048 0.00017 (la). 

The Rb-Sr systematics in Appendix 13.6.5 were used in Fig. 13.27 to date the three sills on Mt. Achernar by the whole-rock Rb-Sr method. The data points of all three siUs scatter above and below errorchron lines which yield dates with overlapping errors that confirm the Middle Jurassic age of the Ferrar Dolerite ... 

Rb-Sr Systematics of the Dolerite Sills on Roadend Nunatak at the Confluence ... 

The Rb-Sr systematics indicate that the flows as well as the dikes of Vestfjella originated in an open magmatic system in which the chemical composition of the magma was altered by interaction with the Precambrian basement rocks that were characterized by having higher Sr/ Sr ratios but lower strontium concentration than the mantle-derived basalt magma. 

The break-away of Australia from East Antarctica between 100 and 65 Ma (Lawver et al. 1991) was initiated by a rift that subsequently evolved into the Southeast-Indian Ridge (Fig. 15.9). Transform faults associated with this spreading ridge may have caused crustal blocks from the Campbell Plateau adjacent to the South Island of New Zealand or from the Tasman Plateau located near Tasmania to be transported south into juxtaposition with the Wilson terrane of northern Victoria Land. The age of accretion of the Bowers and Robertson Bay terranes may have been recorded by the alteration of the Rb-Sr systematics of the high-Ti basalt flows that cap the Pain and Tobin mesas in the Mesa Range of northern Victoria Land (Sections 12.4-12.6). 

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