Modes of extensional faulting controlled by surface processes
Olive, Jean-Arthur L.
Behn, Mark D.
Malatesta, Luca C.
MetadataShow full item record
We investigate the feedbacks between surface processes and tectonics in an extensional setting by coupling a 2-D geodynamical model with a landscape evolution law. Focusing on the evolution of a single normal fault, we show that surface processes significantly enhance the amount of horizontal extension a fault can accommodate before being abandoned in favor of a new fault. In simulations with very slow erosion rates, a 15 km thick brittle layer extends via a succession of crosscutting short-lived faults (heave < 5 km). By contrast, when erosion rates are comparable to the regional extension velocity, deformation is accommodated on long-lived faults (heave >10 km). Using simple scaling arguments, we quantify the effect of surface mass removal on the force balance acting on a growing normal fault. This leads us to propose that the major range-bounding normal faults observed in many continental rifts owe their large offsets to erosional and depositional processes.
Author Posting. © American Geophysical Union, 2014. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 41 (2014): 6725–6733, doi:10.1002/2014GL061507.
Showing items related by title, author, creator and subject.
Nonvolcanic seafloor spreading and corner-flow rotation accommodated by extensional faulting at 15°N on the Mid-Atlantic Ridge : a structural synthesis of ODP Leg 209 Schroeder, Timothy; Cheadle, Michael J.; Dick, Henry J. B.; Faul, Ulrich; Casey, John F.; Kelemen, Peter B. (American Geophysical Union, 2007-06-28)Drilling during ODP Leg 209, dredging, and submersible dives have delineated an anomalous stretch of the Mid-Atlantic Ridge north and south of the 15°20′N Fracture Zone. The seafloor here consists dominantly of mantle ...
Olive, Jean-Arthur; Behn, Mark D.; Mittelstaedt, Eric; Ito, Garrett; Klein, Benjamin Z. (Oxford University Press, 2016-01-27)While elasticity is a defining characteristic of the Earth's lithosphere, it is often ignored in numerical models of long-term tectonic processes in favour of a simpler viscoplastic description. Here we assess the consequences ...
Cemented mounds and hydrothermal sediments on the detachment surface at Kane Megamullion : a new manifestation of hydrothermal venting Tucholke, Brian E.; Humphris, Susan E.; Dick, Henry J. B. (John Wiley & Sons, 2013-09-03)Long-lived detachment faults are now known to be important in tectonic evolution of slow-spreading mid-ocean ridges, and there is increasing evidence that fluid flow plays a critical role in development of detachment ...