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We present a flow law for dislocation-dominated creep in wet quartz derived from compiled experimental and field-based rheological data. By integrating the field-based data, including independently calculated strain rates, deformation temperatures, pressures, and differential stresses, we add constraints for dislocation-dominated creep at conditions unattainable in quartz deformation experiments. A Markov Chain Monte Carlo (MCMC) statistical analysis computes internally consistent parameters for the generalized flow law: urn:x-wiley:21699313:media:jgrb54871:jgrb54871-math-0001 = Aσnurn:x-wiley:21699313:media:jgrb54871:jgrb54871-math-0002e−(Q+VP)/RT. From this initial analysis, we identify different effective stress exponents for quartz deformed at confining pressures above and below ∼700 MPa. To minimize the possible effect of confining pressure, compiled data are separated into “low-pressure” (<560 MPa) and “high-pressure” (700–1,600 MPa) groups and reanalyzed using the MCMC approach. The “low-pressure” data set, which is most applicable at midcrustal to lower-crustal confining pressures, yields the following parameters: log(A) = −9.30 ± 0.66 MPa−n−r s−1; n = 3.5 ± 0.2; r = 0.49 ± 0.13; Q = 118 ± 5 kJ mol−1; and V = 2.59 ± 2.45 cm3 mol−1. The “high-pressure” data set produces a different set of parameters: log(A) = −7.90 ± 0.34 MPa−n−r s−1; n = 2.0 ± 0.1; r = 0.49 ± 0.13; Q = 77 ± 8 kJ mol−1; and V = 2.59 ± 2.45 cm3 mol−1. Predicted quartz rheology is compared to other flow laws for dislocation creep; the calibrations presented in this study predict faster strain rates under geological conditions by more than 1 order of magnitude. The change in n at high confining pressure may result from an increase in the activity of grain size sensitive creep.