Axe reference

n

K₂0%

CaO %

Fe₂O₃  % T

Rb ppm

Sr ppm

Y ppm

Zr ppm

Nb ppm

Ba ppm

Group VI axes

WP1/187

2

1.45

2.90

9.39

34

187

25

148

12

282

WL90/123

2

2.35

4.76

10.08

65

227

39

160

14

419

W91/80

2

2.29

3.84

10.20

85

262

30

175

15

591

WF91/36

3

2.90

3.46

7.01

110

291

32

223

17

671

Example source

2.42

6.53

8.84

97

310

34

179

12

586

analyses*

2.97

4.75

7.54

124

270

40

227

14

747

4.1

3.72

6.68

178

257

42

204

18

728

Group VII axes

WP1/25

1

2.47

2.03

4.77

87

100

33

186

16

311

WP1/44

2

2.51

2.00

4.63

106

94

33

186

14

315

WP2/18

2

3.15

2.85

3.30

113

103

36

209

11

325

WP2/28

1

2.38

2.16

5.49

89

103

37

183

16

335

WP3/2?

2

1.54

2.53

5.13

50

207

31

222

15

495

Example source

2.59

4.87

6.1

94

122

49

195

12

357

analysis**

Axes from

unknown sources

WP3/3

2

3.70

3.26

4.49

140

228

35

283

18

901

WP1/236

2

1.36

3.09

9.09

50

204

17

155

11

571

PXRF sd of the mean*** of

analyses on individual axes:

range

<1-7

<1-21

<1-10

<1-19

<1-9

<1-11

1-11

<1-22

<1-13

average (relative %)

3

12

4

9

4

4

3

7

4

Notes:

* Millward et al. 1978 p. 107, after Fitton 1972, average basaltic andesite and andesite, Borrowdale volcanics; and Sutherland 1982, p. 551, basaltic andesite, Borrowdale.

** Analysis from J Durham, Open University, quoted in Williams-Thorpe et al. 1999, p. 233, Graig Lwyd.

*** calculated as (sd of analyses on one axe /square root of number of analyses); not done for n=1.

Elements in bold are regarded as more reliable indicators of bulk composition see text).

n is the number of PXRF analyses performed for each axe. Iron is total iron as Fe2O3.

Count times were 200 s per isotope; data were recorded before the introduction of the scatter peak surface correction, so only surfaces with relief less than 1 mm are used.

Instrumental precision is between 1 and 10 % (Potts et al. 1995).