Seismotectonics of mid-ocean ridge propagation in Hess Deep.
Hydroacoustic data from the eastern equatorial Pacific reveal low-magnitude seismicity concentrated at the propagating tip of the Galapagos Rise in Hess Deep. The patterns of seismicity and faulting are similar to those observed in the process zone of laboratory-scale propagating tensile cracks. Because the fracture energy required for propagation scales with crack length and process zone size, it follows that ridges can propagate stably in the brittle crust without exceptional resisting forces as proposed by previous models based on linear elastic fracture mechanics.
Floyd
Jacqueline S
JS
Department of Earth and Environmental Sciences, Lamont-Doherty Earth Observatory, Earth Institute, Columbia University, 61 Route 9W, Palisades, NY 10964, USA. jsfloyd@ldeo.columbia.edu
Tolstoy
Maya
M
Mutter
John C
JC
Scholz
Christopher H
CH