Chemistry of biogenic sediments from the equatorial Pacific ...

• Main Authors: Kryc, Kelly A, Murray, Richard W, Murray, David W
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2003
• Subjects: Drilling/drill rig; MultiCorer; Piston corer; Gravity corer; Leg178; TT013; W8803B; Joides Resolution; Thomas G. Thompson; Wecoma; Joint Global Ocean Flux Study JGOFS; Ocean Drilling Program ODP; Antarc*; Antarctic; Antarctic Peninsula
• Online Access: https://dx.doi.org/10.1594/pangaea.725451; https://doi.pangaea.de/10.1594/PANGAEA.725451

To increase our understanding of the mechanisms that control the distribution of Al and Ti within marine sediment, we performed sequential extractions targeting the chemical signatures of the loosely bound, exchangeable, carbonate, oxide, organic, opal, and residual fraction of sediment from a carbonate-dominated regime (equatorial Pacific) and from a mixed opal-terrigenous regime (West Antarctic Peninsula). We observe a systematic partitioning of Al and Ti between sediment phases that is related to bulk Al/Ti. We show that, where we can quantify an Al(excess) component, the dissolved Al is preferentially affiliated with the oxide fraction, resulting in Al/Ti molar ratios of 500-3000. This is interpreted as the result of surface complexation in the water column of dissolved Al onto oxyhydroxides. We also observe a previously undetected Ti(excess) with as much as 80% of the total Ti in the organic fraction, which is most likely a function of metal-organic colloidal removal from the water column. In samples ... : Supplement to: Kryc, Kelly A; Murray, Richard W; Murray, David W (2003): Al-to-oxide and Ti-to-organic linkages in biogenic sediment: relationships to paleo-export production and bulk Al/Ti. Earth and Planetary Science Letters, 211(1-2), 125-141 ...