کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4729671 1640253 2009 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Sediment geochemistry and tectonic setting: Application of discrimination diagrams to early stages of intracontinental rift evolution, with examples from the Okavango and Southern Tanganyika rift basins
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات زمین شناسی
پیش نمایش صفحه اول مقاله
Sediment geochemistry and tectonic setting: Application of discrimination diagrams to early stages of intracontinental rift evolution, with examples from the Okavango and Southern Tanganyika rift basins
چکیده انگلیسی

In this article, we have applied discriminant diagrams and bivariate plots for tectonic setting to Quaternary sediments from the East African Rift System (EARS). Sediment samples used in this study represent two different phases in early stage intracontinental rift evolution: the alluvial fan of the nascent Okavango system and a lacustrine basin within the relatively more mature Tanganyika system. The diagrams for tectonic setting for major elements place the majority of these EARS sediments within the passive margin (PM) setting. Passive margin sandstones are generally enriched in SiO2 and depleted in Na2O, CaO and TiO2 reflecting their highly recycled nature. Based on major element discriminant diagrams, we propose two new fields for early stage intracontinental rift evolution (alluvial fan and lacustrine basin), within the previously defined passive margin field. The rare earth element (REE) patterns from both Okavango and Tanganyika sediments exhibit patterns similar to PAAS, with ash layers from the Rungwe volcanics in the Tanganyika samples exhibiting an enrichment in REE relative to the bulk sediment.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of African Earth Sciences - Volume 53, Issues 1–2, January 2009, Pages 33–44
نویسندگان
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