Table T1. X-ray diffraction estimates of opal and terrigenous sediment abundances for Site 1090. Note: XRD = X-ray diffraction. Leg Site Hole Core Type Sect. Top Base Depth Depth Quartz/Feldspar Clay Minerals to Opal (wt%) (mbsf) (mcd) Ratio Quartz + Feldspar Ratio Carbonate-free fraction (XRD Peak Area) (XRD Peak Area) (XRD Peak Intensity) 177 1090 B 1 H 1 74 75 0.75 0.75 1.1 0.188 177 1090 A 1 H 1 91 93 0.92 0.92 1.29 0.154 17.2 177 1090 A 1 H 2 91 93 2.42 2.42 1.39 0.106 10.7 177 1090 B 1 H 3 74 76 3.25 3.25 1.97 0.219 177 1090 B 2 H 1 76 77 4.97 4.97 1.3 0.23 18.2 177 1090 A 1 H 4 72 74 5.23 5.23 1.76 0.203 177 1090 B 2 H 3 76 77 7.97 7.97 1.55 0.246 177 1090 B 2 H 5 76 77 10.97 10.97 1.29 0.19 18.2 177 1090 B 3 H 1 71 73 14.42 16.17 1.56 0.275 15.7 177 1090 B 3 H 3 72 73 17.43 19.18 1.33 0.202 177 1090 B 3 H 6 75 78 21.97 23.72 1.66 0.254 177 1090 B 4 H 3 76 77 26.97 29.48 1.7 0.141 16.7 177 1090 B 4 H 5 75 77 29.96 32.47 1.55 0.211 13.7 177 1090 B 5 H 4 76 77 37.67 41.28 1.42 0.148 15.7 177 1090 B 6 H 3 76 78 45.97 47.57 0.92 0.288 26.1 177 1090 B 6 H 4 74 76 47.45 49.05 2.36 0.129 15.4 177 1090 B 7 H 3 74 76 55.45 61.75 1.01 0.275 177 1090 B 7 H 5 74 76 58.45 64.75 0.91 0.129 177 1090 B 8 H 2 22 24 62.93 66.64 1.49 0.219 17.2 177 1090 B 8 H 3 76 77 64.97 68.68 1.37 0.29 22.2 177 1090 B 9 H 4 72 73 75.93 79.62 0.65 0.359 177 1090 B 9 H 6 72 73 78.93 82.62 0.85 0.378 18.7 177 1090 B 10 H 3 74 76 83.95 88.52 0.6 0.218 19.7 177 1090 B 10 H 5 74 76 86.95 91.52 0.67 0.244 177 1090 B 11 H 4 72 73 94.93 98.92 0.69 0.247 34.6 177 1090 B 11 H 6 20 21 96.81 100.8 0.62 0.277 177 1090 B 13 H 2 76 77 110.97 116.38 0.44 0.215 27.6 177 1090 B 13 H 6 53 54 116.74 122.15 0.63 0.276 31.6 177 1090 B 14 H 2 72 73 120.43 124.08 0.78 0.232 26.6 177 1090 B 14 H 3 72 73 121.93 125.58 0.7 0.315 177 1090 B 15 H 3 72 73 131.43 137.92 0.97 0.306 29.1 177 1090 B 15 H 5 71 73 134.42 140.91 89.9 177 1090 B 16 H 2 119 121 139.9 146.55 0.97 0.418 28.1 177 1090 B 16 H 5 73 77 143.95 150.6 1.01 0.229 14.7 177 1090 B 17 H 3 74 76 150.45 157.95 0.95 0.283 23.6 177 1090 B 17 H 5 35 37 153.06 160.56 0.79 0.313 177 1090 B 18 H 5 75 76 162.96 170.74 0.97 0.276 31.6 177 1090 B 19 H 5 72 74 172.43 181.92 1.33 0.326 33.6 177 1090 B 20 H 2 122 125 177.94 185.55 0.93 0.351 177 1090 B 21 X 1 72 73 185.43 193.48 0.68 0.367 53.5 177 1090 B 21 X 3 72 73 188.43 196.48 0.95 0.368 37.1 177 1090 B 22 X 3 73 74 198.14 205.75 0.83 0.282 44.6 177 1090 B 22 X 5 73 74 201.14 208.75 0.99 0.341 177 1090 B 23 X 1 72 73 204.83 213.23 0.76 0.289 29.6 177 1090 B 23 X 5 72 73 209.73 218.13 0.72 0.184 26.1 177 1090 B 23 X 7 72 73 212.73 221.13 0.7 0.363 177 1090 B 24 X 1 70 71 214.51 225.47 0.38 0.294 35.6 177 1090 B 24 X 5 86 87 220.67 231.63 0.33 0 12.7 177 1090 B 25 X 1 61 62 224.12 234.83 0.3 0.265 53 177 1090 B 25 X 5 61 62 230.12 240.83 0.51 0 68.5 177 1090 B 26 X 3 21 23 236.42 248.41 0.29 0.362 36.1 177 1090 B 26 X 5 23 26 239.45 251.44 0.5 0.17 43.1 177 1090 B 26 X 7 17 20 242.39 254.38 0.32 0.21 45.6 177 1090 B 27 X 2 97 100 245.39 257.38 0.96 0.159 46.6 177 1090 B 27 X 4 100 102 248.41 260.4 0.42 0.389 28.1 177 1090 B 28 X 4 93 95 258.04 270.03 0.43 0.083 80.4 177 1090 B 29 X 3 23 25 265.54 277.53 0.53 177 1090 B 29 X 5 109 111 269.4 281.39 0.29 0.198 177 1090 B 30 X 1 124 126 273.25 285.24 0.55 0.281 56.5 177 1090 B 30 X 6 30 32 279.81 291.8 0.18 0.167 177 1090 B 31 X 3 64 66 285.35 297.34 0.35 0.121 36.1 177 1090 B 31 X 4 72 74 286.93 298.92 0.32 0.152 31.6 177 1090 B 32 X 1 46 47 291.87 303.86 0.54 0.206 46.1 177 1090 B 32 X 2 46 47 293.37 305.36 0.61 0.287 70.5 177 1090 B 33 X 2 91 92 296.69 308.68 0.49 0.2 33.6 177 1090 B 34 X 3 60 61 304.71 316.7 0.42 0.155 42.1 177 1090 B 34 X 6 43 44 309.04 321.03 0.49 0.22 49 177 1090 B 35 X 2 47 48 312.78 324.77 0.39 0.263 36.6 177 1090 B 35 X 5 60 61 317.41 329.4 0.2 0.264 27.1 177 1090 B 36 X 4 70 71 325.61 337.6 0.19 0.317 23.1 177 1090 B 36 X 5 91 92 327.32 339.31 0.15 0.268 24.1 177 1090 B 37 X 1 71 72 330.72 342.71 0.18 0.191 24.6 177 1090 B 37 X 4 71 72 335.22 347.21 0.24 0.348 19.7 177 1090 B 38 X 3 71 72 343.32 355.31 0.26 0.517 13.2 177 1090 B 38 X 5 71 73 346.32 358.31 0.42 0.431 177 1090 B 39 X 3 71 72 352.92 364.91 0.53 0.531 0.7 177 1090 B 39 X 5 71 72 355.92 367.91 0.71 0.613 9.7 177 1090 B 40 X 3 71 73 362.52 374.51 0.87 0.566 177 1090 B 40 X 5 71 72 365.52 377.51 0.65 0.425 5.2 177 1090 B 41 X 1 84 86 369.25 381.24 0.73 0.461 1.2 177 1090 B 41 X 3 85 87 372.26 384.25 1.86 0.65 177 1090 B 42 X 2 94 96 380.55 392.54 0.79 0.66 4.2 177 1090 B 42 X 6 84 86 386.45 398.44 0.81 0.685 1.7 177 1090 B 43 X 1 65 67 388.46 400.45 1.05 0.727 6.7 177 1090 B 43 X 5 55 57 394.36 406.35 0.84 0.597 8.2