کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4467637 1622272 2010 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Fast or slow melting of the Marinoan snowball Earth? The cap dolostone record
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فرآیندهای سطح زمین
پیش نمایش صفحه اول مقاله
Fast or slow melting of the Marinoan snowball Earth? The cap dolostone record
چکیده انگلیسی

The end of the Neoproterozoic era is punctuated by two global glacial events marked by the presence of glacial deposits overlaid by cap carbonates. Duration of glacial intervals is now consistently constrained to 3–12 million years but the duration of the post-glacial transition is more controversial due to the uncertainty in cap dolostone sedimentation rates. Indeed, the presence of several stratabound magnetic reversals in Brazilian cap dolostones recently questioned the short sedimentation duration (a few thousand years at most) that was initially suggested for these rocks. Here, we present new detailed magnetostratigraphic data of the Mirassol d'Oeste cap dolostones (Mato Grosso, Brazil) and “bomb-spike” calibrated AMS 14C data of microbial mats from the Lagoa Vermelha (Rio de Janeiro, Brazil). We also compile sedimentary, isotopic and microbiological data from post-Marinoan outcrops and/or recent depositional analogues in order to discuss the deposition rate of Marinoan cap dolostones and to infer an estimation of the deglaciation duration in the snowball Earth aftermath. Taken together, the various data point to a sedimentation duration in the range of a few 105 years.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Palaeogeography, Palaeoclimatology, Palaeoecology - Volume 295, Issues 1–2, 1 September 2010, Pages 215–225
نویسندگان
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