Mechanisms of crustal subsidence. Sedimentary basins Isostasy Basins due to stretching Basins due to cooling Basins due to convergence Basins due to tearing of crust. Principles of isostasy. Hawaiin seamount chain with flexed lithospheric lows. Basins due to stretching.
Mantle plumes associated with rifting – not required, but do occur e.g. North Atlantic rifting and emplacement of Tertiary igneous province
Lakes filling half-grabens with thinned lithosphere generating heating and volcanism
Basins due to thermal subsidence after heating following rifting– passive margins
Passive margin accumulates thick sediment that drapes the continent/ocean transition.
Subsidence is slow and exponentially declines as cooling of rifted lithosphere slows.
Crustal depressions due to loading during subduction – accretionary trench
Basins due to loading of continental lithosphere – Foreland Basins