Positions and orientations of geophones in the SAFOD Pilot Hole from Volker Oye Positions east and north are in meters relative to the SAFOD Pilot Hole wellhead, which is located at (in WGS84 reference frame): SAFOD Pilot Hole Lat. = 35.97425794 deg SAFOD Pilot Hole Long. = -120.55210714 deg Depths are in meters above mean sea level (MSL), and were determined by reference to ground elevation at the Pilot Hole wellhead. The ground elevation at the wellhead is 660.5 m MSL, which was obtained by adding the depth of the geoid below the reference ellipsoid (33.2 m, from the National Geodetic Survey's Geodetic Toolkit and their GEOID03 model, see www.ngs.noaa.gov) to the WGS84 ground height above ellipsoid determined by the USGS (627.3 m). Positions are rounded to the nearest 0.5 m for the E/N position and to the nearest 1 m for the depth. The deviation of the borehole was obtained by gyroscopic survey (azimuth and incidence of well path). Orientations were estimated comparing explosion and earthquake data recorded at the downhole geophones with theoretical data obtained from 3D ray tracing (Thurber et al. model). The deviation of the borehole was included. Three rotations are needed to end up with E, N, Z (positive up) components for the recorded geophone channels ch3, ch2, ch1. assign ch1 ? Z (positive down) ch2 ? N ch3 ? E multiply Z component by -1 clockwise rotation of a_c + a_w around the Z-axis (now positive up) clockwise rotation of b_w to remove the dip of the well path along E-component, which is now perpendicular to the well path azimuth. counter clockwise rotation of a_w to put N-component back to global North. geophone#, E[m], N[m], Z[m] rel. to sea level, calibration azimuth a_c, well path azimuth a_w, well path incidence a_w 1, 6, -26, -1436, 264, 345, 2.5 2, 6.5, -27.5, -1396, n.a., 160, 2.6 3, 6, -29, -1356, 120, 8, 2.6 4, 5.5, -31, -1316, 193, 30, 1.6 5, 5, -31.5, -1276, 284, 51, 1.3 6, 4.5, -32, -1236, 180, 57, 1.4 7, 3.5, -32, -1196, 43, 80, 1.4 8, 2.5, -32.5, -1156, 21, 120, 1.2 9, 2.5, -32, -1116, 210, 170, 1.5 10, 2.5, -31, -1075, 299, 190, 1.8 11, 3, -28.5, -1036, 182, 208, 2.7 12, 4, -27, -996, 283, 207, 3.3 13, 5, -25, -956, 338, 202, 3.2 14, 6, -23, -915, 140, 200, 2.3 15, 6, -22, -876, 76, 210, 2 16, 7, -21, -836, n.a., 220, 2 17, 8, -20, -796, 149, 260, 1.9 18, 9, -20, -756, 125, 269, 2.7 19, 12, -20, -716, 39, 266, 3.4 20, 14, -20, -676, n.a., 252, 4 21, 16, -18.5, -636, 255, 242, 3.6 22, 19, -17, -596, 248, 236, 2.8 23, 20, -16.5, -556, 41, 225, 2.8 24, 21, -14, -516, 325, 194, 3.5 25, 21, -11, -475, 131, 172, 5.9 26, 20.5, -8, -436, n.a., 172, 5.5 27, 20, -3, -396, 215, 168, 5 28, 19, -0.5, -356, 228, 157, 4 29, 18, 1, -316, 252, 146, 3.3 30, 17, 2.5, -276, 11, 130, 2.5 31, 15.5, 3.5, -236, 92, 117, 2.2 32, 14, 4, -196, 309, 116, 1.9