Experiments, Using Natural Thermal Waters, on the Illitization of Interlayered Illite-Smectite and the Crystallinity of Illite (open access)

Experiments, Using Natural Thermal Waters, on the Illitization of Interlayered Illite-Smectite and the Crystallinity of Illite

We have investigated experimentally the effects of temperature and time on the extent of interstratification of illite-smectite (I/S) and the crystallinity of illite using natural solutions and clay minerals from the Waiotapu geothermal field, New Zealand. Reactions were conducted in sealed stainless steel vessels kept in an oven at 270 C for 100 days. These reactions increased the illite crystallinity but decreased the expandability of I/S.
Date: January 1, 1995
Creator: Ji, Junfeng & Browne, P.R.L.
System: The UNT Digital Library
The Occurrence of Pyrrhotite in the Ngawha Geothermal System, New Zealand (open access)

The Occurrence of Pyrrhotite in the Ngawha Geothermal System, New Zealand

The Ngawha geothermal system is low in all sulfide minerals, but in comparison to systems in the Taupo Volcanic Zone it contains more widely distributed pyrrhotite which is currently depositing, mainly in fractures. This reflects the high proportion of vapor in the Ngawha system. Pyrrhotite is most common in the upper part of the reservoir and lower part of the aquitard. The Ngawha pyrrhotite is of monoclinic and monoclinic + hexagonal structure.
Date: January 1, 1995
Creator: Cox, M. E. & Browne, P. R. L.
System: The UNT Digital Library