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UK DM project: radioactivity test results

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Rock data (underground sites)

sample (source)	analysis		U conc. (ppb)	Th conc. (ppb)	K conc. (ppm)	comments
	by	method
ZS3 Evaporite (halite)	S I J	AA NAA GES	-        < 60 10(10)	-        < 100 220(40)	> 400 ^(a) -        750(50)
ZS3 Evaporite (halite) - JIF	E	GDMS	15(2)	25(2)	1200(120)	~ 1 g paler part of mid-JIF sample
ZS3 Evaporite (halite)	U	GES	105(10) 70(10)	140(10) 125(10)	1280(200) 1130(200)	`Old' cavern New (JIF) cavern
Gran Sasso (LNGS)     Lab A     Lab B     Lab C	B	GES	180 - 670 < 650 420(100) 670(140)	60 - 400 < 120 60(20) 70(25)	100 - 2000 < 160 160(40) 95(45)	^214Bi ~ 80(20) ppb U
SNO: range     Norite	A	NAA	10^3 - 2.5×10^4 1200	2×10^3 - 7×10^4 3300	1.15×10^4
Soudan	R	GES	80 - 100 ^(b)	200 - 250 ^(c)	800 - 4×10^4
Possible SNBO sites: Nevada         WIPP/Carlsbad	J	GES	3000 - 5000 30 - 110 440(80)	(1.5 - 2.3)×10^4 80 - 150 970(260)	(3.4 - 4.5)×10^4 100 - 5000 4870(60)

Analysts:	Analysis methods:
A: AECL	AA: Atomic Absorption spectroscopy
B: E. Bellotti	GES: Gamma Emission Spectroscopy
I: ICI Tracerco	NAA: Neutron Activation Analysis
J: J. C. Barton
R: K. Ruddick
S: RAL
U: UK Dark Matter Collaboration

Notes:

(a):	K extraction by H2O - may be incomplete.
(b):	from ^214Bi g count, U chain assumed in equilibrium; 2.20 gs in chain.
(c):	from ^208Tl g count, Th chain assumed in equilibrium; 2.65 gs in chain.
SNBO:	Supernova Neutrino Burst Observatory (see D. Cline et al.)

Other remarks:

ppm: parts per million by weight, = conc. × 10^6	ppb: parts per (US) billion by weight, = conc. × 10^9
ppt: parts per (US) trillion by weight, = conc. × 10^12	errors: 0.035(10) (e.g.) means 0.035 ± 0.01 (1 s.)
1 kru = 10^3 decays/day/kg