Pressure solution

Schematic diagram of pressure solution accommodating compression/compaction in a clastic rock. Left box shows the situation before compaction. Blue arrows indicate the flow of particles in solution. Red arrows indicate areas of maximum stress (= grain contacts). Right box shows the situation after compaction. In light coloured areas new mineral growth has reduced pore space.
Deformed coral limestone showing flattening accommodated both by plastic deformation of the corals and pressure solution along stylolites

In structural geology and diagenesis, pressure solution or pressure dissolution is a deformation mechanism that involves the dissolution of minerals at grain-to-grain contacts into an aqueous pore fluid in areas of relatively high stress and either deposition in regions of relatively low stress within the same rock or their complete removal from the rock within the fluid. It is an example of diffusive mass transfer.[1]

The detailed kinetics of the process was reviewed by Rutter,[2] and since then such kinetics has been used in many applications[3] in earth sciences.

Occurrence

Evidence for pressure solution has been described from sedimentary rocks that have only been affected by compaction. The most common example of this is bedding plane parallel stylolites developed in carbonates.

Tectonically deformed rocks also show evidence of pressure solution including stylolites at a high angle to bedding.[4] The process is also thought to be an important part of the development of cleavage.

Theoretical models

A theoretical model was formulated by Rutter, and a recent mathematical analysis was carried out, leading to the so-called Fowler–Yang equations,[5] which can explain the transition behaviour of pressure solution.

See also

References

  1. ↑ Rutter, E.H. (1983). "Pressure solution in nature, theory and experiment.". Journal of the Geological Society, London 140 (5): 725–740. doi:10.1144/gsjgs.140.5.0725. Retrieved 24 November 2010.
  2. ↑ Rutter, E. H. (1976). "The kinetics of rock deformation by pressure solution". Philosophical Transactions of the Royal Society A 283: 203–219. doi:10.1098/rsta.1976.0079. JSTOR 74639.
  3. ↑ Yang, X. S. (2000). "Pressure solution in sedimentary basins: effect of temperature gradient" (PDF). Earth Planet. Sci. Lett. 176: 233–243. doi:10.1016/s0012-821x(99)00321-0. Retrieved 24 November 2010.
  4. ↑ Railsback, L.B.; Andrews L.M. (1995). "Tectonic stylolites in the ‘undeformed’ Cumberland Plateau of Southern Tennessee". Journal of Structural Geology 17: 911–915. Bibcode:1995JSG....17..911B. doi:10.1016/0191-8141(94)00127-L.
  5. ↑ Fowler, A. C.; Yang X. S. (1999). "Pressure solution and viscous compaction in sedimentary basins" (PDF). J. Geophys. Res. B104: 12898–12997. doi:10.1029/1998jb900029. Retrieved 24 November 2010.


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