Salt tectonics

[2] Structures may form during continued sedimentary loading, without any external tectonic influence, due to gravitational instability.

[citation needed] Such structures do not always form when a salt layer is buried beneath a sedimentary overburden.

[4] In an area affected by thrust tectonics, buckling of the overburden layer will allow the salt to rise into the cores of anticlines, as seen in salt domes in the Zagros Mountains and in El Gordo diapir (Coahuila fold-and-thrust belt, NE Mexico).

[citation needed] When one or more salt layers are present during extensional tectonics, a characteristic set of structures is formed.

However, continuing displacement on the fault offsets the base of the salt and causes bending of the overburden layer.

In the Zagros fold and thrust belt, variations in the thickness and therefore effectiveness of the late Neoproterozoic to Early Cambrian Hormuz salt are thought to have had a fundamental control on the overall topography.

This may cause the development of new faults in the cover sequence and is an important consideration when modeling the migration of hydrocarbons.

[9] A significant proportion of the world's hydrocarbon reserves are found in structures related to salt tectonics, including many in the Middle East, the South Atlantic passive margins (Brazil, Gabon and Angola), the Gulf of Mexico,[citation needed] and the Pricaspian Basin.