An assessment of the role of nonlinear reaction kinetics in parameterization of metamorphic fluid flow

• Based on inverse modeling of reaction progress data using a numerical framework that considers coupled advection and diffusion, linear and nonlinear reaction kinetics, and with effective diffusivity given by Archie's law, we show that (1) choice of reaction order has little effect (<0.3 orders of magnitude) on estimates of time-integrated and time-averaged metamorphic fluid fluxes and metamorphic fluid flow durations based on reaction progress data, (2) reaction order must be known for robust determination of time-averaged net reaction rates based on reaction progress data and that underestimation of this term by more than 3 orders of magnitude can arise from assuming linear reaction kinetics, (3) differing reaction orders between laboratory experiments and natural metamorphic systems and/or a nonlinear dependence of effective diffusivity on porosity can explain order-of-magnitude discrepancies between field-based and laboratory-based estimates of time-averaged net reaction rates, and (4) parameterization of metamorphic fluid flow is limited to time-averaged values which fail to account for the possibility that metamorphism occurs in short-lived pulses during longer time periods of metamorphic quiescence.

Subject headings

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Geokemi (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Geochemistry (hsv//eng)

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Geofysik (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Geophysics (hsv//eng)

Publication and Content Type

ref (subject category)

art (subject category)