In Soils of Niue Island, South Pacific
Geochemical Journal, Vol. 24, pp. 371 to 378, 1990 Anomalous Hg contents in soils of Niue Island, South Pacific NEIL E. WHITEHEAD', JOHN BARRIE2 and PETER RANKIN3 Nuclear Sciences Group, Division of Physical Sciences, D.S.I.R. P.O.Box 31-312, Lower Hutt, New Zealand', Avian Mining Ltd., 24 Jindvik Place, Canberra, A.C.T., Australia2 and Division of Land and Soil Sciences, D.S.I.R., Private Bag, Taita, New Zealand3 (Received September 10, 1990; Accepted December 29, 1990) Niue Island, a raised coralline atoll in the South Pacific, has soils that have long been known to have strongly anomalous radioactivity. We now show that there is also a highly anomalous Hg content in the soils. It is associated with the radioactivity and the goethite/gibbsite content and the values are as high as those in soils over known Hg-mineralisation in volcanic settings, though no mineralisation is known on Niue and such an occurrence on this coral island would be geochemically unusual. INTRODUCTION GEOLOGY AND SOILS OF NIUE ISLAND Niue Island in the South Pacific is a raised A detailed description of the geological set coral atoll, located at 19° S and 169° W. The in ting of Niue Is. may be found in Schofield (1959) terior of the island is dolomitised, and is covered and a summary follows. by reddish-brown soils rich in Fe, Al and Niue Island is a raised coral atoll consisting phosphate in the form of goethite, gibbsite and of seaward cliffs rising steeply from the sea but crandallite respectively (the mean soil P205 is girded by a terrace on which sits Alofi, the 4%; Whitehead et al.
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