Other
Scientific paper
Dec 1990
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1990gecoa..54.3391w&link_type=abstract
Geochimica et Cosmochimica Acta, vol. 54, Issue 12, pp.3391-3399
Other
10
Scientific paper
Concretion growth within sandstones can be modelled as a three-stage process, comprising solute supply, solute transport and surface reaction. Solute supply is not thought to be rate determining. R. A. Berner has proposed models for solute transport, which can be adapted to the complex calcite-water system. His model for concretion growth by diagenetic redistribution, which incorporates the replenishment of solute within the porewaters during growth by the dissolution of skeletal aragonite, is reassessed and a new solution presented. The model is also expanded to include the effects of species interconversion during transport. The relative importance of solute transport and surface-reaction can be assessed by calculating model growth times assuming each process to act in the absence of the other. In magnesium-free porewaters growth is transport controlled, in seawater it is surface-reaction controlled. In porefluids with intermediate magnesium-calcium ratios, both processes must be modelled if growth times are to be accurately predicted, with the two processes being rate balanced at the surface of the concretion. The models can be easily modified to include the effects of mobile porefluids. The models have been applied to the concretions of the Valtos Sandstone Formation of Skye, UK. A 1 m diameter concretion is predicted to grow in 9.0 Ma in stationary porefluids, or 5.7 Ma in porefluids flowing at 1 m a -1 .
Dampier Michael D.
Wilkinson Mark
No associations
LandOfFree
The rate of growth of sandstone-hosted calcite concretions does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The rate of growth of sandstone-hosted calcite concretions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The rate of growth of sandstone-hosted calcite concretions will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1630549