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Table 4 U, Th and Pb SIMS zircon data of the micaschist AV16-45, the Lws-micaschist 16–51 and the eclogite AV16-47 from Malone Valley, and the micaschist AV17-07 and the eclogite AV17-16 from Monte Mucrone

From: The evolution of the Sesia Zone (Western Alps) from Carboniferous to Cretaceous: insights from zircon and allanite geochronology

Spot name U (µg/g) Th (µg/g) Th/U f206a Concordia diagram (204Pb corr.) 206Pb/238U
Age (Ma)
 ± 1σ Comments
207Pb/235U  ± 1σ% 206Pb/238U  ± 1σ% ρ
Malone Valley–AV16-45 micaschist
 @16 49 1 0.02 1.43 0.2968 6.29 0.03992 2.00 0.3187 252.3 5.0 Possible Pb loss
 @9 314 4 0.01 2.02 0.3194 5.96 0.04411 1.21 0.2031 278.3 3.3 Rim
 @12 417 2 0.00 0.26 0.3241 2.61 0.04479 1.82 0.6997 282.5 5.0 Rim
 @11 209 4 0.02 1.22 0.2959 5.57 0.04482 2.34 0.4189 282.7 6.5 Rim
 @20 253 3 0.01 0.50 0.3118 3.57 0.04517 2.01 0.5622 284.8 5.6 Rim
 @18 283 4 0.01 0.27 0.3246 2.95 0.04521 1.96 0.6637 285.0 5.5 Rim
 @8 240 3 0.01 0.32 0.3283 3.29 0.04521 2.13 0.6481 285.0 6.0 Rim
 @14 344 5 0.01 0.46 0.3128 3.12 0.04528 1.85 0.5938 285.5 5.2 Rim
 @10 236 3 0.01 0.39 0.3390 3.41 0.04580 2.13 0.6250 288.7 6.0 Rim
 @19 257 3 0.01 0.32 0.3317 2.63 0.04632 1.13 0.4282 291.9 3.2 Rim
 @4 257 4 0.02 2.01 0.3570 5.80 0.04633 2.13 0.3676 292.0 6.1 Rim
 @17 277 3 0.01 0.14 0.3312 4.42 0.04638 3.98 0.9008 292.3 11.4 Rim
 @13 265 4 0.01 0.16 0.3303 2.93 0.04640 2.08 0.7089 292.4 5.9 Rim
 @3 364 4 0.01 0.24 0.3390 2.87 0.04672 1.77 0.6176 294.3 5.1 Rim
 @5 251 4 0.01 0.69 0.3193 4.68 0.04692 2.12 0.4525 295.6 6.1 Rim
 @7 207 3 0.01 1.49 0.3280 5.56 0.04720 2.27 0.4078 297.3 6.6 Rim
 @6 170 8 0.05 0.69 0.3318 4.10 0.04783 2.17 0.5306 301.2 6.4 Rim
 @1 299 4 0.01 0.17 0.3450 2.72 0.04849 1.93 0.7091 305.3 5.8 Rim
 @15 479 5 0.01 0.15 0.3512 2.74 0.04862 2.41 0.8797 306.1 7.2 Rim
 @2 451 24 0.06 0.56 0.6769 2.82 0.08389 1.08 0.3832 519.3 5.4 Core
Malone Valley–AV16-51 Lws-micaschist
 @8 273 52 0.20 0.61 0.2810 5.20 0.04230 2.80 0.5500 267.0 7.0 Rim
 @1 333 9 0.03 0.25 0.3050 3.50 0.04310 2.40 0.6700 272.0 6.0 Rim
 @21 168 42 0.26 0.45 0.3222 5.62 0.04312 4.59 0.8165 272.1 12.2 Rim
 @10 358 23 0.07 0.20 0.3140 3.50 0.04340 2.50 0.7100 274.0 7.0 Rim
 @9 374 7 0.02 0.30 0.2980 3.70 0.04400 2.50 0.6600 277.0 7.0 Rim
 @11b 267 54 0.21 0.20 0.3070 4.10 0.04400 2.80 0.6700 278.0 8.0 Rim
 @14 308 35 0.12 0.37 0.2960 4.20 0.04430 2.50 0.6000 279.0 7.0 Rim
 @24 295 14 0.05 0.62 0.3005 3.82 0.04455 2.08 0.5443 280.9 5.7 Rim
 @2 393 15 0.04 0.18 0.3290 3.30 0.04470 2.40 0.7300 282.0 7.0 Rim
 @27 236 3 0.01 0.23 0.3205 3.29 0.04493 2.25 0.6837 283.3 6.2 Rim
 @28 278 5 0.02 0.45 0.3206 3.00 0.04512 1.15 0.3815 284.5 3.2 Rim
 @20 363 43 0.12 0.19 0.3259 2.89 0.04539 2.04 0.7054 286.1 5.7 Rim
 @19 200 41 0.21 0.12 0.3323 5.12 0.04540 2.24 0.4370 286.2 6.3 Rim
 @15 355 20 0.06 0.49 0.3100 4.00 0.04550 2.30 0.5700 287.0 6.0 Rim
 @13 435 56 0.13 0.00 0.3300 3.30 0.04560 2.20 0.6700 287.0 6.0 Rim
 @22 275 5 0.02 0.24 0.3190 3.07 0.04560 2.06 0.6694 287.5 5.8 Rim
 @7 734 253 0.36 0.07 0.3360 2.40 0.04590 1.90 0.8000 289.0 5.0 Rim
 @23 214 7 0.04 0.46 0.3154 4.57 0.04592 3.38 0.7389 289.4 9.6 Rim
 @12 192 23 0.12 0.37 0.3270 5.10 0.04610 3.00 0.5900 290.0 9.0 Rim
 @16b 230 2 0.01 0.00 0.3390 3.37 0.04626 2.16 0.6395 291.5 6.1 Rim
 @26 418 59 0.15 0.25 0.3246 2.66 0.04640 1.82 0.6824 292.4 5.2 Rim
 @6 167 49 0.30 0.81 0.3250 6.60 0.04660 3.20 0.4800 294.0 9.0 Rim
 @18 210 14 0.07 0.26 0.3362 3.48 0.04709 2.27 0.6516 296.6 6.6 Rim
 @25 333 18 0.06 0.25 0.3261 3.55 0.04712 2.86 0.8062 296.8 8.3 Rim
 @17 339 16 0.05 0.48 0.3195 3.25 0.04720 1.87 0.5753 297.3 5.4 Rim
 @3 322 92 0.30 0.08 0.4000 3.30 0.05520 2.50 0.7400 346.0 8.0 Core
Monte Mucrone–AV17-07 micaschist
 @5 119 9 0.08 1.33 0.1364 6.14 0.01974 2.89 0.4701 126.0 3.6 Possible Pb loss
 @7 348 17 0.05 1.13 0.1573 6.50 0.02366 2.48 0.3815 150.7 3.7 Possible Pb loss
 @26 330 2 0.01 0.04 0.1769 12.10 0.02413 12.00 0.9922 153.7 18.2 Possible Pb loss
 @6 271 2 0.01 0.28 0.1933 3.26 0.02697 2.05 0.6295 171.5 3.5 Possible Pb loss
 @9 345 5 0.01 0.51 0.2143 3.37 0.03078 1.82 0.5410 195.4 3.5 Possible Pb loss
 @29 266 3 0.01 0.25 0.2488 2.92 0.03301 1.91 0.6541 209.4 3.9 Possible Pb loss
 @11 243 2 0.01 0.14 0.2394 3.05 0.03308 2.01 0.6577 209.8 4.2 Possible Pb loss
 @2 392 2 0.00 0.36 0.2313 6.35 0.03412 5.82 0.9161 216.3 12.4 Possible Pb loss
 @32 221 4 0.02 0.43 0.2771 4.43 0.03800 2.06 0.4649 240.4 4.9 Possible Pb loss
 @31 332 8 0.03 0.47 0.2709 3.21 0.03900 1.79 0.5586 246.6 4.3 Possible Pb loss
 @3 220 3 0.01 0.29 0.2731 3.41 0.03958 2.13 0.6252 250.2 5.2 Possible Pb loss
 @12 285 3 0.01 0.43 0.2856 3.87 0.04132 1.97 0.5093 261.0 5.0 Possible Pb loss
 @27 45 2 0.04 1.00 0.2768 6.05 0.04289 1.15 0.1894 270.7 3.0 Possible Pb loss
 @10 507 5 0.01 0.91 0.3026 3.48 0.04328 1.64 0.4720 273.1 4.4 Possible Pb loss
 @22 291 3 0.01 1.79 0.2968 5.59 0.04461 1.91 0.3411 281.3 5.3 Rim1
 @20 178 3 0.02 0.12 0.3194 2.86 0.04512 2.53 0.8831 284.5 7.0 Rim1
 @17 232 5 0.02 0.25 0.3097 3.02 0.04558 1.91 0.6321 287.3 5.4 Rim1
 @19 1010 12 0.01 0.38 0.4202 7.81 0.04624 3.00 0.3843 291.4 5.5 Rim1
 @4 279 4 0.01 0.95 0.3347 3.99 0.04624 1.92 0.4814 291.7 5.5 Rim1
 @24 211 6 0.03 2.55 0.3743 14.47 0.04629 3.70 0.2554 292.9 10.6 Rim1
 @8 196 4 0.02 0.62 0.3232 4.16 0.04649 2.19 0.5257 293.4 6.3 Rim1
 @30 237 6 0.03 0.68 0.3558 14.32 0.04657 1.90 0.1324 296.9 5.5 Rim1
 @33 239 62 0.27 1.41 0.5544 4.05 0.04714 2.03 0.5027 419.8 8.3 Core
 @35 205 98 0.49 0.21 0.5560 2.68 0.06730 2.05 0.7644 445.5 8.8 Core
 @21 370 107 0.30 0.04 0.5671 1.97 0.07155 1.67 0.8477 451.5 7.3 Core
 @16 229 123 0.55 0.07 0.5864 2.44 0.07256 2.02 0.8283 463.3 9.0 Core
Monte Mucrone–AV17-16 eclogite
 @6 12 1 0.06 2.21 0.2901 25.77 0.03508 8.02 0.3113 222.3 17.5 Possible Pb loss
 @7b 48 16 0.34 0.00 0.2588 9.14 0.03689 8.00 0.8751 233.5 18.3 Possible Pb loss
 @4 43 14 0.33 0.29 0.3114 6.91 0.04214 4.13 0.5974 266.1 10.8 Core
 @11 16 4 0.27 2.29 0.2535 26.99 0.04236 7.21 0.2671 267.4 18.9 Core
 @12 41 13 0.33 1.76 0.2713 15.17 0.04270 4.21 0.2776 269.5 11.1 Core
 @9 289 48 0.17 0.26 0.3281 3.76 0.04357 2.75 0.7306 275.0 7.4 Core
 @9 50 20 0.42 0.58 0.3406 9.73 0.04772 3.93 0.4039 300.5 11.5 Possible inheritance
 @10 78 42 0.56 1.06 0.4848 6.35 0.06240 3.20 0.5046 390.2 12.1 Possible inheritance
  1. Data were processed using SQUID 2.50. The dates that were not used for the age calculations shown in Figs. 3, 6 and 10 are reported in italics
  2. a% of common 206Pb on total 206Pb