The erosion of mountains and thus the rocks of which they are comprised has generally been explained by the geomorphological process of thermal stress, periglacial frost shattering and minor chemical weathering operating at the observed inferred rates, that is very slowly.
However some South African researchers have discovered that lightning is actually the dominant erosional mechanism of high mountains and not periglacial or other “climatically-mediated” weathering processes, (Source, Lightning as a geomorphic agent on mountain summits: Evidence from southern Africa, Jasper Knight and Stefan W. Grab, in Geomorphology, Vol. 204, 1 Jan 2014, Pages 61-70).
The explanation is that the angular rock debris invariably found on mountain peaks and thus scree slopes etc is most likely the result of lightning impacts.
This leads to the wide spread belief of Australian Aboriginals who assert that the present day topography is the result of the activity of the mythical Rainbow Serpent. This rainbow serpent is clearly not lightning but more likely as a far larger electrical effect between the Earth and some external perturbation in the ionosphere and magnetosphere causing long duration electric discharges machining the earth’s surface to form the present day topography; aka electro-machining.
If this aboriginal observation is accurate, then the accumulation of vast layers of sands and clays may not be the product of slow chemical and periglacial weathering and erosion but from more catastrophic erosional events associated with planetary scaled electrical discharges than present-day atmospheric lightning impacts as described by the Knight and Grab.