1. Sedimentary input to the source of Lesser Antilles lavas: A Li perspective Ming Tang 1, Roberta Rudnick 1, Catherine Chauvel 2 1.Department of Geology, University of Maryland 2.Universite´ Grenoble Alpes Mt. Pelée, Martinque Fang-Zhen Teng Ming Tang

2. mantle altered MORB serpentinite- diapir ~+4 -11 to +4 0 to +4* +20  +4 +3 to +14 +20 forearc decollement island arc fluid 0 30 60 90 120 km Can Li be used to trace recycling? After Zack et al., 2003, EPSL eclogite  7 Li *Marschall et al. (2007) sediments -5 to +15 What do arc lavas tell us?

3. Most arcs = MORB (maybe a bit heavier) Global Arc Lavas

4. IN: fluids with slab Li & B OUT: fluids with slab B, but little Li Mantle Retention of Lithium? From Tomascak et al. (EPSL,2002)

5. Labanieh et al., 2012, J. Petrol. The case for subducted sediments in the Lesser Antilles lavas Sediments +10 +5 0 -5 -10 -15 -20

7. Global Subducting Sediments Site 543 Bouman et al., 2004 Averages from Plank, 2014, TOG

8. Our Project: Analyze  7 Li in subducting sediments Martinque lavas Do we see the sedimentary signature reappearing in the lavas? Mt. Pelée, Martinque

9. Tang et al., 2014, following Plank, 2014 Subducting Sediments

10. Mt. Pelée, Martinque Lesser Antilles subducting sediments are global end member Tang et al., 2014, GCA Lesser Antilles subducting sediments are clearly much lighter than mantle

11. Tang et al., 2014, GCA Submarine eruption – interaction with seawater Martinique lavas Li clearly influenced by sedimentary input

12. Tang et al., 2014, GCA No evidence for crustal assimilation: sediments added to mantle source

13. Mt. Pelée, Martinque Mixing scenarios

14. Conclusions Li can make it through the mantle wedge! Clear subducted terrigneous sediment signature in Martinque lavas Probably added through melts of sediments

15. Congratulations Fang-Zhen!