Tectonic Evolution of the Southern Negros Geothermal Field and Implications for the Development of Fractured Geothermal Systems

Figure 7

Group 2 NW-SE normal fault. (a) The structure at the midstream of Okoy River with the estimated fault trace projected as a red plane (see Figure 1(c), iii, for the location). (b) Section view of the SE side of the ravine showing the main structure. (c) Close-up photo of the small-scale dilational jogs which are common in the damage zone. (d) Stereonet showing the main fault planes in black, the average plane in red, and secondary and likely conjugate structures in green. Poles to the tensile fractures and veins are represented as blue dots. (e) Photomicrograph of the host rock, completely replaced by silica and also cut by a quartz vein.

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