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John Buchanan was New Zealand's first locally-based official scientific illustrator, preparing illustrations for a wide range of scientific publications. He was also an experienced botanist, publishing papers on the local flora. From 1862 until his retirement in 1885 Buchanan worked as an assistant to James Hector, undertaking fieldwork and a variety of technical projects. From 1868 onwards he undertook the time-consuming task of preparing illustrations for the first eighteen volumes of the Transactions of the New Zealand Institute. [ABSTRACT FROM AUTHOR]

Towards the end of his career exploring remote parts of Westland, Charlie Douglas produced a giant, coloured, topographic and geological map of the region which was never exhibited during his lifetime. The mineral locations he identified were later investigated by prospecting parties in 1936–1937, and geological information from the map was important in the recognition of the Alpine Fault in 1941–1942. After being stored in Hokitika, Greymouth and Lower Hutt, the map is now held at Archives New Zealand, and a digital version is available online. [ABSTRACT FROM AUTHOR]

The Berlins Porphyry consists of many shallow intrusive igneous bodies emplaced c. 110–112 Ma over an area of c. 140 km2 near Westport. There is little variation in bulk chemistry or mineralogy, but texturally the rocks range from glassy dacite (hyalodacite) to granodiorite. Evidence suggests a two-stage model for emplacement – first, explosive brecciation of the country rock and mixing with fluidised, volatile-rich magma to form hyalodacite, followed by less vigorous emplacement of magma to form plutons that crystallised to microgranodiorite and granodiorite. [ABSTRACT FROM AUTHOR]

James Hector produced the first geological map of New Zealand in 1865, based on local surveys by Ferdinand Hochstetter (Auckland and Nelson), J. Coutts Crawford (Wellington), Julius Haast (Canterbury) and his own mapping in Otago. Three updated versions of the map were produced in 1869, 1873 and 1884. Under Hector's direction, the New Zealand Geological Survey delineated the main geological features of New Zealand, but it was to be many years before the Alpine Fault was recognised and the problems of dating and correlating the older rocks were resolved. [ABSTRACT FROM AUTHOR]

Presents a study which evaluated the elemental mobility during lower greenschist to amphibolite facies metamorphism of a uniform turbidite suite (Greenland Group, New Zealand). Information on the evaluation process; Geological background of New Zealand; Metamorphism of the Greenland Group.

Understanding and, ultimately, controlling the properties of amor-phous materials is one of the key goals of material science. Among the different amorphous structures, a very important role is played by colloidal gels. It has been only recently understood that colloidal gels are the result of the interplay between phase separation and arrest. When short-ranged attractive colloids are quenched into the phase-separating region, density fluctuations are arrested and this results in ramified amorphous space-spanning structures that are capable of sustaining mechanical stress. We present a mecha-nism of aggregation through arrested demixing in binary colloidal mixtures, which leads to the formation of a yet unexplored class of materials--bigels. This material is obtained by tuning interspecies interactions. Using a computer model, we investigate the phase behavior and the structural properties of these bigels. We show the topological similarities and the geometrical differences be-tween these binary, interpenetrating, arrested structures and their well-known monodisperse counterparts, colloidal gels. Our find-ings are supported by confocal microscopy experiments performed on mixtures of DNA-coated colloids. The mechanism of bigel for-mation is a generalization of arrested phase separation and is therefore universal. [ABSTRACT FROM AUTHOR]

During the may 1968 Inangahua earthquake, a 2.8 x 106 m³ landslide dam was formed in highly weathered granitic material in the headwaters of Ram Creek on the West Coast of the South Island, New Zealand. The landslide dam impounded a lake immediately upstream of the dam for c. 13 yr without breaching. The dam crest was breached on 29 April 1981 during an intense rainstorm, resulting in complete and catastrophic failure of the Ram Creek landslide dam. A dambreak flood caused substantial damage downstream. The longevity of the dam was probably due to its resistance to internal erosion, the small size of catchment, and the lack of high intensity/long duration rainfall in the catchment area. Three internationally derived geomorphic indices (impoundment index, Blockage index, and Dimensionless Blockage index) used to predict the stability (post-formation dam development) of landslide dams were applied to the Ram Creek landslide dam; all three indices correctly predicted the short term (<12 yr) development of the dam but failed to predict the catastrophic failure some 13 yr after formation. It is impossible to predict when a sufficiently intense event will cause overtopping failure of a landslide dam. It is conceivable that the Ram Creek dam could have remained intact for many more decades if the 1981 storm had been a little less intense, or centred a few kilometres farther away. Hence, the stability of this landslide dam was essentially a statistical concept, because the event against which it is stable is stochastic in nature. [ABSTRACT FROM AUTHOR]