Hot Cracks in the Pacific Plate

Lineations in the gravity field are widespread on the Pacific plate but are not yet explained by plate tectonics. We propose that they represent warps caused by accumulation of thermoelastic stress in the cooling lithosphere. Stress is relieved along parallel cracks where young volcanic ridges sometimes develop. Both the crack spacing and gravity amplitude are predicted by the elastic plate theory and variational principle. The absence of the gravity lineations in the young lithosphere provides an upper bound on the fracture energy of the lithosphere. Our model suggests that both the gravity lineations and the volcanic ridges are a natural consequence of lithospheric cooling.