Weathering and damage

Abstract

[1] Weathering of rock surfaces is often associated with a surface dissolution process. Chemical interactions occur on grain boundaries and diffusion is the controlling process. A dissolution boundary layer (rind) develops adjacent to the weathering surface. We quantify the extent of dissolution by introducing a damage variable f, f = 0 for pristine rock, and when f = f 0 the rock disintegrates. We assume that the variations of the damage variable are given by the diffusion equation. We solve two problems. The first is for the structure of the transient dissolution boundary layer prior to surface disintegration. We find an incubation time t i before active weathering (disintegration) begins. The second is the solution for steady state weathering with a constant weathering velocity v w . Our results are entirely consistent with weathering studies on Carrera marble gravestones in the United Kingdom.

Mechanical weathering and rock erosion by climate‐dependent subcritical cracking

“…Our rock erosion framework is supported by a number of experimental and field observations, as well as by theoretical studies: Even over relatively short (Holocene) timescales, regardless of rock type or environment, the outer millimeter to centimeter thick portion of rock surfaces is characterized by chemically and physically altered weathering rinds that thicken and intensify in their accumulation of weathering products through time [ Birkeland , ; Burke and Birkeland , ; Hoke and Turcotte , ; Warke and Smith , ]. Accumulation of weathering products presumably “primes” this outer shell for wholesale exfoliation and/or susceptibility to thermal stresses, as proposed by some work [ Lamp et al , ; Tratebas et al , ]. A large majority of all subaerially exposed rocks show evidence of this type of surface parallel fracturing and/or granular disintegration regardless of environment and/or stress loading process.…”

“…Accumulation of weathering products presumably “primes” this outer shell for wholesale exfoliation and/or susceptibility to thermal stresses, as proposed by some work [ Lamp et al , ; Tratebas et al , ]. A large majority of all subaerially exposed rocks show evidence of this type of surface parallel fracturing and/or granular disintegration regardless of environment and/or stress loading process. For example, freezing, fire, salt hydration, and thermal cycling have all been demonstrated to induce exfoliation [e.g., Al‐Omari et al , ; Turkington and Paradise , ; Vasile and Vespremeanu‐Stroe , ], and such spallation occurs in subsurface rock weathering as well [ Fletcher and Brantley , ]. Similar surface fragmentation models have been explored and validated, for example, in the context of dissolution weathering rinds [ Hoke and Turcotte , ] or salt weathering [ Wells et al , ].…”

“…1. Even over relatively short (Holocene) timescales, regardless of rock type or environment, the outer millimeter to centimeter thick portion of rock surfaces is characterized by chemically and physically altered weathering rinds that thicken and intensify in their accumulation of weathering products through time [Birkeland, 1982;Burke and Birkeland, 1979;Hoke and Turcotte, 2002;Warke and Smith, 2000]. Accumulation of weathering products presumably "primes" this outer shell for wholesale exfoliation and/or susceptibility to thermal stresses, as proposed by some work [Lamp et al, 2017;Tratebas et al, 2004].…”

Role of clay minerals in the physicomechanical deterioration of sandstone

“…There are several reasons for the study of stone decay as a useful analogy for rock weathering in natural settings. Among them, one is the availability of easily characterized stone in a dated monument, which enables an accurate study of weathering processes and rates [ Dragovich , 1978; Meierding , 1981; Pope et al , 2002; Hoke and Turcotte , 2002]. Another reason is the relative ease of performing laboratory and field tests using stone samples under well‐established conditions that help single out a particular weathering mechanism [ Rodríguez‐Navarro and Doehne , 1999].…”

A mathematical model of sulphite chemical aggression of limestones with high permeability. Part I. Modeling and qualitative analysis

“…It is well known that sulphur and nitrogen oxides are transformed, through complex reaction pathways, into gaseous nitric and nitrous acids and into acidic sulphates as suspended particles. In particular, SO 2 and NO 3 react with calcium carbonate stones to produce sulphates and nitrates, which, due to their solubility in water, may be drained away or, if protected from the rain, may form crusts, that eventually exfoliate Bandyopadhyay 1999, Hoke andTurcotte 2002).…”