Rift

[3] Typical rift features are a central linear downfaulted depression, called a graben, or more commonly a half-graben with normal faulting and rift-flank uplifts mainly on one side.

Major rifts occur along the central axis of most mid-ocean ridges, where new oceanic crust and lithosphere is created along a divergent boundary between two tectonic plates.

Segment boundaries often have a more complex structure and generally cross the rift axis at a high angle.

[7] Contrary to what was previously thought, elevated passive continental margins (EPCM) such as the Brazilian Highlands, the Scandinavian Mountains and India's Western Ghats, are not rift shoulders.

At the onset of rifting, the upper part of the lithosphere starts to extend on a series of initially unconnected normal faults, leading to the development of isolated basins.

[8] During the climax of lithospheric rifting, as the crust is thinned, the Earth's surface subsides and the Moho becomes correspondingly raised.

The amount of subsidence is directly related to the amount of thinning during the rifting phase calculated as the beta factor (initial crustal thickness divided by final crustal thickness), but is also affected by the degree to which the rift basin is filled at each stage, due to the greater density of sediments in contrast to water.

[10][11] This has generally been replaced by the 'flexural cantilever model', which takes into account the geometry of the rift faults and the flexural isostasy of the upper part of the crust.

Successful rifting leads to seafloor spreading along a mid-oceanic ridge and a set of conjugate margins separated by an oceanic basin.

Margin architecture develops due to spatial and temporal relationships between extensional deformation phases.

[17] As a consequence, upper mantle peridotites and gabbros are commonly exposed and serpentinized along extensional detachments at the seafloor.

[19][20] Recent studies indicate that post-collisional granites in collisional orogens are the product of rifting magmatism at converged plate margins.

[citation needed] The sedimentary rocks associated with continental rifts host important deposits of both minerals and hydrocarbons.