Three-dimensional thermal sensitivity analysis of cooling of a magma chamber in the Los Azufres geothermal field, Michoacán, Mexico

Geothermal Energy

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Table 5 Cubic best-fit equations for thermal gradient in the geothermal reservoir as a function of either chamber depth or volume, or both, from all 63 simulated models

Equation #	Depth of the top of magma chamber (d, km)	Centroid of the magma chamber (dc, km)	Volume of the magma chamber ( V, km³)	R ²	Equation^a
17	5.0 to 9.0	7.000 to 12.875	-----------	0.691799	δT = (299 ± 289) - (50 ± 89) dc + (2.0 ± 9.1) dc² - (0.009 ± 0.306) dc³
18	-----------	-----------	300 to 600	0.000000	δT = (11 ± 239) + (1 ± 1680) V - (2 ± 3820) V² + (1 ± 2820) V³
19	5.0 to 9.0	7.000 to 12.875	300 to 600	0.838748	$\begin{array}{l} δT = (677 \pm 238) - (169 \pm 68) dc + (13.9 \pm 7.0) {dc}^{2} - (0.392 \pm 0.234) {dc}^{3} \\ - (0.069 \pm 0.69) V + (0.37 \pm 1.58) V^{2} - (0.31 \pm 1.17) V^{3} \end{array}$

^aThe coefficients and their errors in the equations are rounded values according to the flexible rules put forth by Verma (2005).