I would like to thank: A.Wulff and M.Rhodes for the XRF analyses, P. Voldet for the ICP-AES analyses, F. Ramos for the TIMS analyses, Y.Vinzce and T.Thon-That for the
40Ar/39Ar analyses, and F. Parat for the electron microprobe analyses of apatite. I’m also grateful to J. Barclay for making me available her unpublished experimental data and for many discussions about occurrences of horblende-bearing mafic lavas. Field work was funded by the ASSN.
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