Amorphous silica transport in the Ganges basin: Implications for Si delivery to the oceans

Summary, in English

Rivers transport similar to 6 x 10(12) mol yr(-1) of dissolved Si (DSi) from the continents to the oceans. They also carry amorphous silica (ASi), solid phases likely to dissolve in seawater. Unfortunately, the magnitude of this flux is poorly constrained at a global scale. We present 92 new ASi values from suspended particulate matter (SPM) from the Ganges basin. Bulk SPM is 1.2% ASi, and mean ASi concentrations are 65 mu M, of comparable magnitude to DSi concentrations. Our results also indicate a) ASi is not evenly distributed in the water column of large rivers, b) the ASi is not a wholly biogenic Si endmember and c) the ASi flux is, to a first order, a function of the SPM load. Our results suggest that the ASi particulate load is much greater than previously believed, rivaling that of the DSi load with important implications for the global Si cycle and oceanic Si isotopic budget. (C) 2014 The Authors. Published by Elsevier BAT. This is an open access article under the CC BY-NC-ND license

• Author: Patrick Frings; Wim Clymans; Daniel Conley
• Department/s: Quaternary Sciences
• Publishing year: 2014
• Language: English
• Pages: 271-274
• Publication/Series: Procedia Earth and Planetary Science
• Volume: 10
• Full text: - 1 MB; Download statistics
• Links: http://dx.doi.org/10.1016/j.proeps.2014.08.059
• Document type: Journal article
• Publisher: Elsevier
• Topic: Geology
• Keywords: global silicon cycle; river amorphous silica; silicon isotopes; river fluxes
• Conference name: Geochemistry of the Earth's Surface (GES) Meeting
• Conference date: 2014-08-18 - 2014-08-23
• Status: Published
• ISBN/ISSN/Other: ISSN: 1878-5220