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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