کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5161900 1502286 2014 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Impact of river channel shifts on tetraether lipids in the Rhône prodelta (NW Mediterranean): Implication for the BIT index as an indicator of palaeoflood events
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
Impact of river channel shifts on tetraether lipids in the Rhône prodelta (NW Mediterranean): Implication for the BIT index as an indicator of palaeoflood events
چکیده انگلیسی
We tested the applicability of the BIT (branched and isoprenoid tetraether) index as a proxy for palaeoflood events in the river-dominated continental margin of the Gulf of Lions (NW Mediterranean). We compared the concentrations of branched glycerol dialkyl glycerol tetraethers (br GDGTs) and crenarchaeol in suspended particulate matter (SPM) collected downstream in the Rhône River, as well as in surface sediments and a ca. 8 m piston core from the Rhône prodelta. The core covered the last 400 yr, with four distinct intervals recording the river influence under natural and man-induced shifts in four main channels of the river mouth (Bras de Fer, Grand Rhône, Pégoulier and Roustan). The results indicate that there are mixed sources of br GDGTs and crenarchaeol in the prodelta, complicating application of the BIT index as an indicator of continental organic carbon input and thus as a palaeoflood proxy. However, the sedimentary BIT record for the period when continental material was delivered by the river more directly to the core site (Roustan phase; 1892 to the present) mimics the historical paleoflood record. This shows the potential of the BIT index as a palaeoflood proxy, provided that the delivery route of the continental material by rivers to the core sites remains constant over time. The study also highlights the idea that shifts in river channels should be taken into account for the use of the BIT index as a palaeoflood proxy.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Organic Geochemistry - Volume 75, October 2014, Pages 99-108
نویسندگان
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