Biogeochemical cycle of silica in an apolyhaline interdunal holocene lake (Chad, N'Guigmi region, niger)
During the Holocene, the apolyhaline conditions in interdunal ephemeral lakes in the Lake Chad region led to various diagenetic processes, which resulted in: (a) clay authigenesis, (b) organic matter lithification (plants and cyanobacterial mats), (c) precipitation of sodium silicate (magadiite, kenyaite, zeolite), and (d) chert neoformation. Each step in this diagenetic process involves silica, which can be highly mobile under such conditions. Therefore, the paleoenvironmental variations can be investigated using the Si cycle.http://link.springer. de/link/service/journals/00114/bibs/9086010/90860475.htm</HEA
Sebag
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UMR 5561 CNRS Biogeosciences, Universite de Bourgogne, 6 Blvd. Gabriel, F-21000 Dijon, France.
Verrecchia
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Durand
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