Gravity faulting as a mechanism of topographic adjustment

Abstract

Small discontinuous scarps, invariably facing ridges, are described from near Arthurs Pass and have been noted along the length of the main dividing ranges of the South Island. These are deduced to be the result of gravitational adjustment of topography of high relief oversteepened by past glaciation in greywacke and low-grade schist. This readjustment is thought to be triggered by earthquakes. They are not tectonic in origin and care must be taken to differentiate these scarps from those of tectonic origin.

Paraglacial rock-slope stability

“…It has been found useful to group the paraglacial factors that result in rock slope failures into three types: preconditioning, preparatory and triggering factors (Glade and Crozier, 2005) ( (Thorarinsson et al, 1959;Rapp, 1960;Beck, 1968;Bovis, 1982;Augustinus, 1992Augustinus, , 1995bAlexandrowicz, 1997). As Bovis (1982) pointed out, although steepening and debuttressing occurred in every glaciated valley, not every slope has failed, and he concluded, as others had done (e.g.…”

Quaternary faulting in the Tatra Mountains, evidence from cave morphology and fault-slip analysis

“…Gravity could also have caused the movements if the weakest plane is not parallel to the slope. It is enough for the strike direction to be sub-parallel to the ridge course (Beck 1968). Evidence of this process can be seen at fault No.…”

Thrust-induced collapse of mountains-an example from the "Big Bend" region of the San Andreas Fault, western Transverse Ranges, California

“…Subtle linear scarps or sackungen (Beck, 1968;Varnes and others, 1989), both uphill-and downhill-facing and as long as several hundred meters, are locally preserved. The presence of sackungen indicates deep-seated rock creep, although all sackungen are eroded and appear to be inactive.…”

“…11) and is bounded on the south and west by thrusts that place mostly Cretaceous granitic rocks above the Pliocene sedimentary rocks of the Ridge Basin (Jennings and Strand, 1969 Figure 9. Three models for gravitational spreading of mountains, after (A) Beck (1968), (B) Mahr (1977), and (C) Kellogg (2001b). Distance across each diagram is ~5-10 kilometers.…”