Sub-aqueous sulfur volcanoes at Waiotapu, New Zealand

Exhumed, sub-aqueous sulfur mounds occur in the Waiotapu geothermal area, N ew Zealand. The extinct mounds are <2 m high and composed of small (<0.5 cm ) hollow spheres. and occasional teardrop-shaped globules. They are located within a drained valley that until recently was connected to Lake Whangiot erangi. They were formed a maximum of 820 +/- 80 years BP as a result of th e rapid sub-aqueous deposition of sulfur globules, formed when fumarolic ga ses discharged through molten sulfur pools. Similar globules are now being formed by the discharge of fumarolic gases through a sub-aqueous molten sul fur pool in Lake Whangioterangi. (C) 1999 CNR. Published by Elsevier Scienc e Ltd. All rights reserved.