Editors’ Highlights are summaries of recent papers by AGU’s journal editors.
Source: Journal of Geophysical Research: Solid Earth
Mid-ocean ridges are often presented as more or less two-dimensional features, with a great deal of continuity in the along-ridge direction and most variation happening perpendicular to the ridge. New seismic images presented by Wang et al. [2025] show that this is emphatically not the case for the Lucky Strike segment of the Mid-Atlantic Ridge, a slow-spreading segment which was examined by the 2005 SISMOMAR experiment using wide-angle seismic surveys conducted along and across the ridge. The authors apply a state-of-the-art full waveform inversion — a method that calculates structure from the entire recorded wave — to these data, and find much stronger structural variation along the ridge than across it, with a thick, low seismic velocity lower crust and deep Moho beneath the center of the segment.
The authors interpret this thick, slow lower crust at the center of the segment to represent the result of lateral focusing of magma towards a central Lucky Strike volcano. The ends of the segment lack this lower crust, and have lower upper crustal velocities, suggesting that they receive more evolved magma that propagates horizontally from the center via dikes. The Lucky Strike segment thus illustrates how slow spreading ridges can be dramatically three-dimensional in nature.
Citation: Wang, Z., Singh, S. C., Minshull, T. A., & Crawford, W. C. (2025). Fine-scale crustal velocity structure at the lucky strike segment of Mid-Atlantic ridge from full waveform inversion of wide-angle seismic data. Journal of Geophysical Research: Solid Earth, 130, e2024JB029982. https://doi.org/10.1029/2024JB029982
—Andrew Frederiksen, Associate Editor, JGR: Solid Earth