Thermal contraction joints in a spreading seafloor as origin of fracture zones

IF newly formed oceanic crust is moving away from a spreading axis, it can be expected to contract by cooling. Vertically, the cooling is expressed in the existence and cross-sectional shape of the mid ocean ridges, where there is a relationship between depth of the ocean and age of the crust 1 . A steady state solution for a model of a lithospheric plate which cools while moving 2–4 is compatible with data on topographical height.