Record Details
Field | Value |
---|---|
Title | Comment on "Do geochemical estimates of sediment focusing pass the sediment test in the equatorial Pacific?" by M. Lyle et al. |
Names |
Francois, Roger
(creator) Frank, Martin (creator) Rutgers van der Loeff, Michiel (creator) Bacon, Michael P. (creator) Geibert, Walter (creator) Kienast, Stephanie (creator) Anderson, Robert F. (creator) Bradtmiller, Louisa (creator) Chase, Zanna (creator) Henderson, Gideon (creator) Marcantonio, Franco (creator) Allen, Susan E. (creator) |
Date Issued | 2007-03-06 (iso8601) |
Abstract | Accurately estimating the vertical flux of material reaching the seafloor from the overlying surface waters is essential for the paleoceanographic reconstruction of a wide variety of oceanic processes. Two approaches are currently being used. One consists of estimating mass accumulation rates (MAR) between dated horizons as the product of linear sedimentation rates, sediment dry bulk densities, and concentrations. One pitfall with this approach is that sediments can be redistributed on the seafloor by bottom currents, and their accumulation may not necessarily reflect the true vertical rain rate originating from the overlying water column. To address this problem, the method of ²³⁰Th normalization was developed [Bacon, 1984]. This method is based on the assumption that the rapid scavenging of ²³⁰Th produced in the water column by decay of dissolved uranium results in its flux to the seafloor always being close to its known rate of production. To the extent that this assumption is correct, scavenged ²³⁰Th can be used as a reference to estimate the settling flux of other sedimentary constituents and to correct for sediment redistribution on the seafloor [Henderson and Anderson, 2003; Francois et al., 2004]. |
Genre | Article |
Topic | paleoflux |
Identifier | Francois, R., et al. (2007), Comment on ‘‘Do geochemical estimates of sediment focusing pass the sediment test in the equatorial Pacific?’’ by M. Lyle et al., Paleoceanography, 22, PA1216. |