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How does rifting and faulting create mountains away from continental margins?

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continental landform Davis's proposed landscape-development states. The morphology shown is not actually time-indicative. For example, A could be a gully system in soft sediment or a canyon such as the Royal Gorge in Colorado, which is millions of years old. The ridge-ravine topography of B would normally develop under humid conditions, but the river meandering on alluvium indicates a prior or extraneous non-humid aggrading mechanism. The riverine plain of C implies a complex history of planation and aggradation in a current fluvial mode.

Mountains that form away from continental margins, often referred to as intracontinental mountain belts, are primarily created through crustal shortening or rifting processes.12

Crustal Shortening

In some regions, mountains form within a continental mass rather than at plate boundaries. These belts are characterized by block faulting, where large crustal blocks are uplifted along steep faults. This process can result in elongated, sharply defined mountain ranges. For example, the Rocky Mountains in the United States formed through such internal deformation, which may be linked to distant tectonic interactions like subduction.12

Rifting and Faulting

Rift-type mountains originate where the continental crust undergoes extension, often associated with the development of a spreading ridge. This process involves:2
* High-angle faulting: The crust fractures and shifts, creating a characteristic horst-and-graben topography, where uplifted blocks (horsts) form mountains and dropped blocks (grabens) form basins.2
* Volcanism: This extension is frequently accompanied by basaltic volcanism.2
* Variable scale: Rifting can be localized, such as the East African Rift, or widespread, as seen in the Basin and Range Province of the western United States.2