Extended Data Fig. 9: Velocity-depth profiles.
From: Lower oceanic crust formed by in situ melt crystallization revealed by seismic layering
(a) One-dimensional velocity-depth profiles from the tomographic velocity model in Extended Data Fig. 1 and (b) from the FWI model in Fig. 2a, between the distances from 112 km to 192 km at an increment of 2 km. (c) and (d) show two velocity profiles from the tomographic model in Extended Data Fig. 1 and the FWI model in Fig. 2a, at distance 146 km and 182 km from the MAR, respectively. The thin dashed line indicates the interpreted Layer 2A/2B boundary from FWI; the bold dashed blue and black lines indicate the boundaries of Layer 2/3 from the tomographic model and the FWI model, respectively. The top low-velocity layer (indicated by letter ‘H’) could be related to hydrothermal alteration.
