Crustal structure of the Mid-Atlantic ridge crest at 37° N |
| |
| Authors: | C M R Fowler |
| |
| Institution: | Department of Geodesy and Geophysics, Madingley Road, Cambridge CB3 0EZ |
| |
| Abstract: | Summary. A structural model of the Mid-Atlantic Ridge at 37° N is proposed on the basis of travel-time data and synthetic seismograms. At the ridge axis the crust is only 3 km thick and overlies material with an anomalously low'upper mantle'velocity of 7.2 km s?1. Crustal thickening and the formation of layer 3 and a layer with velocity 7.2–7.3 km s?1 takes place within a few kilometres of the axis, producing a 6–7 km thick crust by less than 10 km from the axis. A normal upper mantle velocity of 8.1 km s?1 exists within 10 km of the axis. Shear waves propagate across the axis, thus precluding the existence of any sizeable magma chamber at shallow depth. |
| |
| Keywords: | |
|
|
