Geochemistry of metasedimentary units of the Cambro-Ordovician Ross Orogen in North Victoria Land and Oates Land, Antarctica ...

• Main Authors: Henjes-Kunst, Friedhelm, Schüssler, Ulrich
• Format: Dataset
• Language: English
• Published: PANGAEA 2003
• Subjects: ORDINAL NUMBER; LATITUDE; LONGITUDE; Sample comment; Sample code/label; Lithologic unit/sequence; Area/locality; Comment; Silicon dioxide; Titanium dioxide; Aluminium oxide; Iron oxide, Fe2O3; Manganese oxide; Magnesium oxide; Calcium oxide; Sodium oxide; Potassium oxide; Phosphorus pentoxide; Sulfite; Loss on ignition; Barium; Cerium; Cobalt; Chromium; Gallium; Lanthanum; Niobium; Nickel; Rubidium; Scandium; Strontium; Thorium; Vanadium; Yttrium; Zinc; Zirconium; Oates Land; Robertson Bay; Victoria Land; Antarc*; Antarctica
• Online Access: https://dx.doi.org/10.1594/pangaea.704725; https://doi.pangaea.de/10.1594/PANGAEA.704725

Metasediments in the three early Palaeozoic Ross orogenic terranes in northern Victoria Land and Oates Land (Antarctica) are geochemically classified as immature litharenites to wackes and moderately mature shales. Highly mature lithotypes with Chemical Index of Weathering values of >=95 are typically absent. Geochemical and Rb-Sr and Sm-Nd isotope results indicate that the turbiditic metasediments of the Cambro-Ordovician Robertson Bay Group in the eastern Robertson Bay Terrane represent a very homogeneous series lacking significant compositional variations. Major variations are only found in chemical parameters which reflect differences in degree of chemical weathering of their protoliths and in mechanical sorting of the detritus. Geochemical data, 87Sr/ 86Sr t=490 Ma ratios of 0.7120 - 0.7174, epsilonNd, t=490 Ma values of -7.6 to -10.3 and single-stage Nd-model ages of 1.7 - 1.9 Ga are indicative of an origin from a chemically evolved crustal source of on average late Palaeoproterozoic formation age. ... : Position of sample G8-39b is estimated from map ...