Figure 2. Along-axis profiles of isotopic ratios from the Southeast Indian Ridge (SEIR) between 114°E and 138°E. The horizontal scale (in kilometers) is the distance from the eastern bounding transform of the Australian Antarctic discordance (AAD). Open symbols and lightly shaded field = Pacific-type mid-ocean-ridge basalt (MORB). Solid symbols and darker field = Indian-type MORB (from Pyle et al., 1992). Triangles = data from Klein et al. (1988), squares = data from the edge of the AAD, and triangles with included circles = samples from west of the AAD. In the lowermost panel, filled circles = dredge depths and open circles = subsidence curve fits to flanks.