Browne, P.R.L. 1978 Petrological logs of drillholes : Kawerau geothermal field. Lower Hutt: New Zealand Geological Survey. Report NZGS 84. 57 p.
Abstract: This report gives brief petrographic descriptions of cores from the Kawerau geothermal field. Since drilling began (1952) four petrologists (A. Steiner, W.A. Watters, P.R.L. Browne and W.A. Elders) have worked on the Kawerau investigation project and, not surprisingly, their core descriptions differ in style and the amounts of detail given; nor was the same rock classification used. I have therefore re-examined all available thin sections with a view to achieving a greater uniformity in rock naming and to make correlations between drillholes more reliable. Descriptions of cores up to, and including, KA 17 are based mainly on thin section examination only but cores from drillholes KA 19, 21-26 have also been studied by x-ray diffraction (J.A. Olivecrona, P.R.L.B.); differential thermal analyses have been made (M.W. Gardner) of all cores from KA 26 and some from KA 22, 23 and 25. (auth)