QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. Johnson et al. 2009 Variable water within the MGVF (1-6 wt%) Jorullo melt inclusions show highest water at ~5-6 wt%, Hoya Alvarez the lowest at ~1 wt% Johnson et al. suggest variably depleted mantle source along volcanic front (Jorullo) and more fertile source in back-arc (Hoya Alvarez) QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.