Citation

BibTex format

@article{Nielsen:10.1016/j.gca.2016.03.010,
author = {Nielsen, SG and Yogodzinski, G and Prytulak, J and Plank, T and Kay, SM and Kay, RW and Blusztajn, J and Owens, JD and Auro, M and Kading, T},
doi = {10.1016/j.gca.2016.03.010},
journal = {Geochimica et Cosmochimica Acta},
title = {Tracking along-arc sediment inputs to the Aleutian arc using thallium isotopes},
url = {http://dx.doi.org/10.1016/j.gca.2016.03.010},
}

RIS format (EndNote, RefMan)

TY  - JOUR
AB - Sediment transport from the subducted slab to the mantle wedge is an importantprocess in understanding the chemical and physical conditions of arc magma generation. The Aleutian arc offers an excellent opportunity to study sediment transport processes because the subducted sediment flux varies systematically along strike (Kelemen et al., 2003) and many lavas exhibit unambiguous signatures of sediment addition to the sub-arc mantle (Morris et al.,1990). However, the exact sediment contribution to Aleutian lavas and how these sediments are transported from the slab to the surface are still debated. Thallium (Tl) isotope ratios have great potential to distinguish sediment fluxes in subduction zones because pelagic sediments and lowtemperaturealtered oceanic crust are highly enriched in Tl and display heavy and light Tl isotope compositions, respectively, compared with the upper mantle and continental crust. Here, we investigate the Tl isotope composition of lavas covering almost the entire Aleutianarc a well as sediments outboard of both the eastern (DSDP Sites 178 and 183) and central (ODP Hole 886C) portions of the arc. Sediment Tl isotope compositions change systematically from lighter in the Eastern to heavier in the Central Aleutians reflecting a larger proportion of pelagic sediments when distal from the North American continent. Lavas in the Eastern and CentralAleutians mirror this systematic change to heavier Tl isotope compositions to the west, which shows that the subducted sediment composition is directly translated to the arc east of Kanaga Island. Moreover, quantitative mixing models of Tl and Pb, Sr and Nd isotopes reveal that bulk sediment transfer of ~0.6-1.0% by weight in the Eastern Aleutians and ~0.2-0.6% by weight in the Central Aleutians can account for all four isotope systems. Bulk mixing models, however,require that fractionation of trace element ratios like Ce/Pb, Cs/Tl, and Sr/Nd in the Central and Eastern Aleutians occurs after the sediment c
AU - Nielsen,SG
AU - Yogodzinski,G
AU - Prytulak,J
AU - Plank,T
AU - Kay,SM
AU - Kay,RW
AU - Blusztajn,J
AU - Owens,JD
AU - Auro,M
AU - Kading,T
DO - 10.1016/j.gca.2016.03.010
SN - 1872-9533
TI - Tracking along-arc sediment inputs to the Aleutian arc using thallium isotopes
T2 - Geochimica et Cosmochimica Acta
UR - http://dx.doi.org/10.1016/j.gca.2016.03.010
UR - http://hdl.handle.net/10044/1/30157
ER -