Consequently, close spatial association of moissanite and silicates with X Mg ≤0.9 demonstrates chemical disequilibrium and indicates temperatures lower than those allowing for diffusional equilibration.
This led Winton et al. (2010) to decompose the temperature response into equilibrium (∆T eq) and disequilibrium (or remaining) components, such that ∆T′ ≡ ∆T eq − ∆T varDelta {T}_{mathrm{eq}}=F/{lambda}_{mathrm{eq}} (16) varDelta {T}^{prime }=varepsilon N/{lambda}_{mathrm{eq}} (17).
During the aqueous fluid circulation, the primary magmatic minerals or glass in the volcanic rocks (called "protolith" below) are generally in disequilibrium with the fluid because temperatures, pressures, and H2O fugacity are quite different from those during the volcanic rock formation.
Indeed, mixing of high temperature hydrothermal fluids (>200 °C) with cold seawater promotes chemical disequilibrium in redox reactions that can support microbial metabolism45, likely leading to increased niche space capable of supporting higher diversity.
The one-dimensional modelling provides a good insight into overpressure buildup by disequilibrium compaction and pore fluid expansion due to increasing temperature.
The rounded and embayed shapes of albite and K-feldspar grains (Figure 10) are attributed to disequilibrium marginal melting, which has occurred due to a decrease in the melting temperature of feldspar caused by the release of OH- from hydrous phases or by viscous shear heating at >1,100°C (Spray 1992).
For example, it is also possible that Idh-1 is linked to another locus which is under temperature-driven selection, and that the allele frequencies observed in nature reflect this linkage disequilibrium [ 5, 27].
Correlations between growth and adaptation to low temperatures within populations are often weaker than those among populations, suggesting they result from linkage disequilibrium and not pleiotropy (Hannerz et al. 1999; Howe et al. 2003).
The flow is even fast enough to carry elevated disequilibrium SiO2 concentrations from below (Figure 7). Figure 7 Comparison between measured aquifer temperatures and calculated reservoir temperatures in the Upper Muschelkalk (black dots) and the Upper Jurassic aquifer (red dots).
The growth of a metamorphic mineral at a low degree of disequilibrium (i.e., a system close to equilibrium, implying a small overstep from the equilibrium temperature and a low degree of supersaturation for the metamorphic reaction) may result in an equigranular metamorphic texture because interfacial energy becomes an important control on crystal morphology and size.
