Figure F9. Strain, reflected in formation pressure changes in Hole 1027C on the flank of the Juan de Fuca Ridge, following two seismogenic slip events (red stars) near the ridge axis. The sense of strain (expansive in A, contractional in B) is in each case consistent with that predicted on the basis of the earthquake moment tensors. The CORK observatory in this hole is completed in highly permeable oceanic crust; lateral drainage from beneath the low-permeability sediment cover causes eventual drainage of the anomalous pressure. (After Davis et al., 2001.)
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