Does the nucleation of clay minerals control the rate of diagenesis in sandstones?. (2nd January 2018)

• Record Type: Journal Article
• Authors: Wilkinson, Mark
• Is Part Of: Clay minerals. Volume 50:Number 3(2015:Jun.)
• Page Start: 275
• Page End: 281
• Publication Date: 2018-01-02
• Subjects: nucleation, -- clay mineral, -- diagenesis; Clay minerals -- Periodicals; Clay -- Periodicals; 549.6
• DOI: 10.1180/claymin.2015.050.3.01
• Languages: English
• ISSNs: 0009-8558

Abstract

Abstract: Nucleation is much more important for clay minerals than for other authigenic cements as clay crystals are very small, so that a very large number of clay crystals must be nucleated. The role of this difficult kinetic step in the diagenesis of sandstones has not been considered adequately as a ratedetermining process. The relationship between pore-fluid supersaturation and the rate of nucleation of a mineral is very different from the relationship between supersaturation and the rate of crystal enlargement; thus the two processes will act at very different rates. A diagenetic model that predicts claymineral formation but omits the nucleation stage may make unreliable predictions. This may account partially for the discrepancy between numerical simulations of CO2 injection that predict high degrees of reaction between the CO2 and the host rock, and the results of studies of natural analogues that have much lower degrees of reaction.