Trace element transport during dehydration processes in the subducted oceanic crust: 1. Experiments and implications for the origin of ocean island basalts

Details Trace element transport during dehydration processes in the subducted oceanic crust: 1. Experiments and implications for the origin of ocean island basalts Trace element transport during dehydration processes in the subducted oceanic crust: 1. Experiments and implications for the origin of ocean island basalts

Apr 1997

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1997e%26psl.148..193k&link_type=abstract

Earth and Planetary Science Letters, Volume 148, Issue 1, p. 193-205.

Computer Science

62

Scientific paper

Dehydration experiments on natural amphibolite have been carried out under upper mantle P/T conditions, in order to examine transportation of trace elements during dehydration processes in the subducted oceanic lithosphere. Pb, Nd, and Rb are more readily transported by aqueous fluids during amphibolite dehydration than U-Th, Sm, and Sr, respectively. The results indicates that the dehydration of subducted oceanic crust may result in large increases in U/Pb, Th/Pb and Sm/Nd ratios, and a decrease inRb/Sr ratios of subducted oceanic crust. This ultimately leads to higher Pb and Nd isotopic ratios, and lower Sr isotopic ratios in the subducted oceanic crust than the present MORB source mantle, given a sufficiently long periods of isolation in the mantle. It follows that the very high Pb isotopic ratios observed in some ocean island basalts, known as HIMU, can be readily achieved by incorporation of ancient subducted crust into their mantle source. However, Sr and Nd isotopic ratios cannot be explained by bulk mixture of the ancient subducted oceanic crust with depleted or primitive mantle, but require significant fractionation ofNd/Sr ratios in the subducted oceanic crust before mixing with mantle material. Possible processes to produce Sr and Nd isotopic compositions similar to that of HIMU may involve partial melting of recycled subducted basaltic crust under lower mantle conditions and refertilization of primitive mantle by the partial melt.

Affiliated with

Also associated with

No associations

Rating

Trace element transport during dehydration processes in the subducted oceanic crust: 1. Experiments and implications for the origin of ocean island basalts does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Trace element transport during dehydration processes in the subducted oceanic crust: 1. Experiments and implications for the origin of ocean island basalts, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Trace element transport during dehydration processes in the subducted oceanic crust: 1. Experiments and implications for the origin of ocean island basalts will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1317679