Dissolution at dislocation etch pits in quartz

Brantley, Susan L.; Crane, Stephanie R.; Crerar, David A.; Hellmann, Roland; Stallard, Robert F.

doi:10.1016/0016-7037(86)90087-6

Cited by 192 publications

(106 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The chemical composition of the bulk materials gives a large amount of water as loss on ignition (LOI) showing that the water table level is high and the whole profile remains moist during the year. The triangular etched pits of our study are very similar to those observed in the single crystal experiments of Brantley et al (1986) and Hicks (1985). According to these experiments, sand dissolution took place at very high and very low temperatures.…”

Section: Discussionsupporting

confidence: 88%

“…This may have resulted from downward transport of surface materials along fractures and micro cracks induced by shrinkage during weathering or leaching, or they may have formed in-situ from silica-rich solutions. These observations, are supported by the presence of rounded quartz grains at the base of the profiles, which further indicates that quartz dissolution is continuing at all depths as reported by Brantley et al (1986).…”

Section: Discussionsupporting

confidence: 82%

“…The observation of pitting which changes as a function of depth suggests that the existence of etched pits is controlled by some depth-related factors. As fluids pass through the profile, silica dissolved from the soil grains increase the silica concentration towards saturation, as obtained experimentally by Brantley et al (1986). The surface morphology of the weathered sand grains which show differing patterns of etching, may result from eluviation processes.…”

Section: Discussionsupporting

confidence: 58%

“…According to these experiments, sand dissolution took place at very high and very low temperatures. Brantley et al (1986) concluded that the concentration of silica could control pitting from experiments they carried out at high temperatures. A more thorough investigation of chemical etching as a function of soil depth and/or increasing weathering and fluid chemistry is necessary in order to provide further information and insights into fluid history in the weathering environment.…”

Section: Discussionmentioning

confidence: 99%

See 3 more Smart Citations

The Origin of Etch Pits Recorded on Residual Grain Surfaces from Kaolinized Granitic Rocks West Region Cameroon

Wouatong¹,

Yerima²,

Fouateu³

et al. 2013

ESR

View full text Add to dashboard Cite

The weathering of some granitic rocks in the West Region of Cameroon (Central Africa) was examined by X-ray diffraction (XRD) and X-ray fluorescence Spectrometer (XRF) in conjunction with Scanning Electron Microscopy (SEM). Kaolinite and illite were the most predominant weathering products whereas gibbsite, goethite and maghemite were also found in small amounts; only residual quantities of quartz and potassium feldspar were observed. The geochemical study shows the mobility of major elements during the progressive kaolinization of granitic rocks. The main trend is the loss of elements, with high losses of CaO, Na 2 O and MgO, slight losses of SiO 2 while Al 2 O 3 and K 2 O appear to increase with weathering intensity. Chemical index of alteration (CIA) shows a high value (68-95%). The scanning electron microscope analysis reveals the existence of several surface features that reflect the effect of mainly chemical actions on the quartz and K-feldspar grains. Quartz and K-feldspar crystals from kaolinized granitic rocks show low to very high chemical etching attributed to weathering under moderate to severe environmental conditions such as low pH, high temperature and humidity and extreme leaching typical of tropical climatic conditions. Etched pit densities on quartz surfaces increase with weathering, as a result of increasing silica concentrations in pore fluids.

show abstract

Section: Discussionsupporting

confidence: 88%

Section: Discussionsupporting

confidence: 82%

Section: Discussionsupporting

confidence: 58%

Section: Discussionmentioning

confidence: 99%

See 2 more Smart Citations

The Origin of Etch Pits Recorded on Residual Grain Surfaces from Kaolinized Granitic Rocks West Region Cameroon

Wouatong¹,

Yerima²,

Fouateu³

et al. 2013

ESR

View full text Add to dashboard Cite

show abstract

“…Etch pits (Brantley et al, 1986;Lüttge, 2006) and "leached or re-precipitated layers" (Hellmann et al, 2003), which are not present at equilibrium, suggest that the extrapolation of equilibrium rate constants to highly undersaturated solutions may not be justified. Testing the applicable range for the PDB in cases affected by these and other complications will be difficult.…”

Section: Introductionmentioning

confidence: 99%

A stable isotope doping method to test the range of applicability of detailed balance

Liu¹,

Rimstidt²,

Zhang³

et al. 2016

Geochem. Persp. Let.

View full text Add to dashboard Cite

Processes of silicate karstification associated with pan formation in the Darwin–Koolpinya area of northern Australia

Borger

McFarlane²,

Ringrose³

2004

Earth Surf Processes Landf

View full text Add to dashboard Cite

Lyons Lagoon, one of many small pans near Darwin, Northern Australia, occurs in lateritized terrain. Formation by structurally facilitated silicate karstification of the parent Cretaceous sandy sediments was earlier proposed. This paper presents the results of thin section microscopy and scanning electron microscopy with energydispersive X-ray study of pan sediments with a view to assessing the extent to which they reflect the geomorphological/hydrogeological history. Severe corrosion was found to overprint the impact features of the primary sands, attributed to aggressive leaching and consistent with formation of the depression by karstification when the water table was low. Formation of a smectitic matrix is considered to have followed when the water table was high. Upon subsequent lowering of the water level leaching was resumed, altering smectite to kaolinite and resulting in incongruent dissolution of kaolinite to leave a siliceous residuum. At least two cycles of high followed by low water levels are recognized. Such periodic changes of levels are considered essential to pan formation within freely draining lateritic terrain. The processes of pan formation and alteration of pan sediments (essentially residual deposits) is ongoing, biocorrosion being implicated as an important mechanism. Incongruent kaolinite dissolution, to leave a silica residuum, a hitherto apparently unrecognized process, raises the possibility that silcrete may form as a relative accumulation which is synchronous with lateritic leaching in more elevated topographic positions.

show abstract

Dissolution at dislocation etch pits in quartz

Cited by 192 publications

References 36 publications

The Origin of Etch Pits Recorded on Residual Grain Surfaces from Kaolinized Granitic Rocks West Region Cameroon

The Origin of Etch Pits Recorded on Residual Grain Surfaces from Kaolinized Granitic Rocks West Region Cameroon

A stable isotope doping method to test the range of applicability of detailed balance

Processes of silicate karstification associated with pan formation in the Darwin–Koolpinya area of northern Australia

Contact Info

Product

Resources

About