Zealand Geological Research Articles

New Zealand’s offshore sedimentary basins

ABSTRACT We present new interpretations and mapping that define the distribution, extent, and sediment thickness of 25 primarily offshore sedimentary basins within New Zealand’s Exclusive Economic Zone (EEZ) and Extended Continental Shelf (ECS). These basins cover ∼1.64 million km2 of the ∼5.8 million km2 (∼28%) of New Zealand’s offshore territory. The sedimentary basins formed in different tectonic settings. Most initially formed during the mid- to Late Cretaceous in either a rift-related setting during Gondwana break-up, or within or atop the paleo Gondwana subduction margin. Others formed due to the onset of mid-Paleogene sea-floor spreading, or are related to Neogene–Quaternary subsidence driven by subduction processes. Slight to significant late Paleogene to Quaternary tectonic overprints are pervasive in basins located within the Hikurangi subduction margin’s deformation zone. Knowledge of the distribution and extent of these basins was refined during the multi-year ‘Atlas of Petroleum Prospectivity’ research programme, which builds upon many decades of previous research. New digital structure, isochore, and paleogeographic maps, along with annotated seismic reflection profiles, have been developed where data coverage has allowed, using a consistent set of age-equivalent seismic horizons tied to the New Zealand Geological Timescale. Maximum total sediment thickness of ∼11 km occurs in Taranaki Basin.

Strong Upper‐Plate Heterogeneity at the Hikurangi Subduction Margin (North Island, New Zealand) Imaged by Adjoint Tomography

AbstractWe use earthquake‐based adjoint tomography to invert for three‐dimensional structure of the North Island, New Zealand, and the adjacent Hikurangi subduction zone. The study area, having a shallow depth to the plate interface below the North Island, offers a rare opportunity for imaging material properties at an active subduction zone using land‐based measurements. Starting from an initial model derived using ray tomography, we perform iterative model updates using spectral element and adjoint simulations to fit waveforms with periods ranging from 4–30 s. We perform 28 model updates using an L‐BFGS optimization algorithm, improving data fit and introducing P‐ and S‐wave velocity changes of up to ±30%. Resolution analysis using point spread functions show that our measurements are most sensitive to heterogeneities in the upper 30 km. The most striking velocity changes coincide with areas related to the active Hikurangi subduction zone. Lateral velocity structures in the upper 5 km correlate well with New Zealand geology. The inversion reveals increased along‐strike heterogeneity on the margin. In Cook Strait we observe a low‐velocity zone interpreted as deep sedimentary basins. In the central North Island, low‐velocity anomalies are linked to surface geology, and we relate velocity structures at depth to crustal magmatic activity below the Taupō Volcanic Zone. Our velocity model provides more accurate synthetic seismograms with respect to the initial model, better constrains small (50 km), shallow (15 km) and near‐offshore velocity structures, and improves our understanding of volcanic and tectonic structures related to the active Hikurangi subduction zone.

Dr. J. M. Bell, FRGS: A Canadian Auxiliary Geographer in New Zealand

Using Hodder’s notion of “biography as method,” this paper examines the geographical endeavours of James Mackintosh Bell, Director of the New Zealand Geological Survey from 1905 to 1911, in New Zealand and Canada. Canadian born, Harvard trained, Bell has a significant place in the history of geology in New Zealand and mining geology in Canada, yet much of his writing was explicitly geographical in orientation. This essay analyses this body of work and its significance and limitations in adding to and disseminating knowledge of the geography of NZ, particularly. Bell credentialed himself geographically as a Fellow of the Royal Geographical Society (FRGS). The FRGS were important builders of geographical knowledge in NZ from the 1850s up to the establishment of university geography in the 1930s when formal geographical research commenced. Geologists were a numerically significant group amongst the NZ FRGS, distinctive in that they held university qualifications, and Bell was particularly wide ranging in his geographical interests.

Correlation between the Warepan/Otapirian and the Norian/Rhaetian stage boundary: implications of a global negative δ13Corg perturbation

ABSTRACT The Norian/Rhaetian boundary interval (Late Triassic) is characterised by significant biotic turnover and severe climatic changes. However, this boundary still awaits formal definition. We have investigated the δ13Corg record within a well-preserved marine sequence exposed in the Kiritehere section, North Island, New Zealand. This section was located at higher latitudes (above 60°S) during the Triassic, and is considered the best exposed section representative of the New Zealand Warepan/Otapirian stage boundary. This is a regional boundary pertaining to the Zealandia region of Gondwana; it is described in the New Zealand Geological Timescale (NZGT) and it has been recognised as being correlative with the Norian/Rhaetian boundary. Using an integrated chemo- and biostratigraphic approach, we have identified a negative δ13Corg shift close to the disappearance of the standard-sized monotids (fossil bivalves) in the Kiritehere section. We interpret this negative shift to be the same negative δ13Corg shift that has been proposed to define the base of the Rhaetian. However, the position of the negative δ13Corg shift in the Kiritehere section is ca. 6.40 m below the accepted position of the Warepan/Otapirian boundary, based on biostratigraphy. This δ13Corg isotopic shift, best thought of as a chemostratigraphic event, is regarded here as a global phenomenon.

HARTLEY TRAVERS FERRAR (1879–1932) AND HIS GEOLOGICAL LEGACY IN ANTARCTICA, EGYPT AND NEW ZEALAND

ABSTRACT Hartley Travers Ferrar was the geologist on Scott's first expedition to the Antarctic (the ‘Discovery’ Expedition) in 1901–1904. Ferrar undertook the first geological surveys in the Transantarctic Mountains, which he mapped to 83°S, and made some discoveries of major scientific importance, such as fossil leaves, later identified as Glossopteris indica. He then worked in Egypt, Palestine and New Zealand, and was Acting Director of the New Zealand Geological Survey when he died suddenly in 1932. Little has been acknowledged about Ferrar's other contributions to geology, which were vast, and included pioneering work on irrigation and hydrogeology in Egypt, as well as a series of geological mapping campaigns in New Zealand. The latter extended to systematic soil surveys in New Zealand, in particular in Central Otago, where soil types and their properties were characterized in the field and laboratory. This paper outlines some of Ferrar's key contributions to New Zealand geoscience, as well as some of his notable overseas achievements.

Life on the Wellington Fault: Managing Geological Collections and Earthquake Risk

GNS Science is home to New Zealand’s national rock, mineral and fossil collections. The National Petrology Reference Collection (NPRC) is a ‘nationally significant’ collection of rocks and minerals from on- and off-shore New Zealand, Antarctica and the rest of the world. The National Paleontological Collection (NPC) is another nationally significant collection; of fossil material from New Zealand, the South West Pacific region and Antarctica, with some overseas additions. Their status as nationally significant collections mean that GNS Science is contracted by the New Zealand Government to provide long-term collection management. Collectively, the NPC and NPRC constitute more than 200,000 samples, dating from the earliest days of New Zealand geology exploration in the late 1800s. The collections continue to grow by hundreds to thousands of samples per year, and are loaned nationally and internationally for scientific research. They are by far the largest collections of fossils, rocks and minerals housed in New Zealand, and are important earth science archives for the entire Zealandian Southern Ocean region. The collections are housed on-site at GNS Science in Lower Hutt, a few hundred meters from the surface trace of the Wellington Fault and within striking distance of other active faults that could generate major earthquakes. Best estimates suggest that the Wellington Region has an average return time of about 150 years for very strong or extreme ground shaking. Such proximity to this significant, active hazard means that steps must be taken to ensure the long-term security and integrity of the collections in the event of earthquake shaking, as well as other natural and non-natural disasters. To that end, the collection managers have written and implemented disaster mitigation, preparedness and recovery plans for the National Petrology Reference Collection and National Paleontological Collection. Here we define the earthquake hazard posed by the Wellington Fault, assess the risk to the collections, and present steps taken to manage that risk.

Finding Matilda: deconstructing women’s invisibility in Finding New Zealand’s Scientific Heritage

ABSTRACTFormal narratives of New Zealand science have largely focused on the development of science infrastructure in New Zealand since the appointment of James Hector to head the New Zealand Geological Survey in 1865. This short communication uses the discourses of the 2015 conference, Finding New Zealand’s Scientific Heritage to explore the impact of institutional history, and the high number of participants (for example, retired scientists), on New Zealand historiography of science. I suggest this approach has resulted in the absenting or camouflaging of the contribution of women. The short communication then explores approaches that might mitigate against these effects, suggesting ‘starting thought from women's lives’ (Harding S. 1991. Whose science? Whose knowledge? Thinking from women’s lives. Ithaca, NY: Cornell University Press, p. 150) as a primary mode for novel revisions of history of science in New Zealand.

Four Mile man: a short note on the life of Richard (Dick) Wright Willett

ABSTRACTR. W. (Dick) Willett was director of the New Zealand Geological Survey (NZGS) from 1956 to 1967, when he initiated an ambitious project to publish a new national geological map at a scale of 1:250,000 (the Four Mile project). It was completed within a decade, and subsequently used as a model by overseas geological surveys. In 1967 he was appointed assistant director-general of DSIR and subsequently served as the president of the Royal Society of New Zealand from 1970 to 1974.

Book review: <i>James Hector. Explorer, Scientist, Leader</i>

This book is by a prominent New Zealand geologist and science historian about one of the leading 19th century scientists, James Hector (1834–1907). His influence on New Zealand’s science in the second half of the century was so dominant that one science historian called this period “Hector hegemony”. But contrary to his contemporary, the German-born scientist Julius Haast, the full story of Hector’s achievements for New Zealand’s science had never been told and his name survived mainly in connection with the Hector dolphin, an endangered endemic species that he was the first to describe. But as of now, Nathan’s book will fill this gap. This is a well written, aptly designed and richly illustrated chronological biography of Hector’s life and work. It is remarkable how many details were unearthed from a large number of archives and libraries and especially from the letters Hector exchanged with friends and colleagues, mostly with Julius Haast, director of the Canterbury Museum at Christchurch, and Joseph Hooker, director of the Royal Botanic Gardens at Kew, UK; Nathan had previously edited the correspondence of Hector and Haast and a bibliography of Hector’s publications prior to the book under review (Nathan et al., 2012, 2015). James Hector was born in Edinburgh; he graduated from his home university in 1856 as a doctor of medicine and developed a strong interest in geology, biology and tramping. Consequently, his first involvement in a major scientific exploration led him to Western Canada, where he joined an expedition into the Canadian Rockies with the aim of finding a suitable pass for the railway to connect the western Prairies with the Pacific. The pass discovered by this expedition is still in use; its name “Kicking Horse Pass” recalls an incident which almost cost Hector his life. His reputation as a keen and successful explorer reached the distant colony of New Zealand. In the 1860s, the Otago Provincial Council at Dunedin initiated a geological survey of the province with the aim of detecting new mineral and coal deposits and a suitable route linking the province of Otago to the remote west coast. Hector was appointed as government scientist and arrived in Dunedin in 1862. After an effective exploration on land and sea he served as one of the curators for the New Zealand Exhibition in Dunedin in 1865. In the same year, he arrived in Wellington as a government employee. Nathan’s book marks the 150th anniversary of Hector’s appointment as New Zealand’s first government scientist, the year when the seat of government was moved from Auckland to Wellington. From this year on, Hector was the great organiser of New Zealand’s science. At first he was involved in the foundation of a colonial museum, the forerunner of Te Papa, which is now New Zealand’s National Museum; he organised the central New Zealand Institute, which included the publication of the annual and influential Transactions and Proceedings. He masterminded the first comprehensive New Zealand Geological Survey (now GNS Science), which resulted in the publication of the first Geological Map of New Zealand. Hector also became the conductor and supervisor of the Colonial Botanical Gardens, the Colonial Observatory and was director of the meteorological stations. He used the expanding telegraph network to establish a nationwide recording system for the location and intensity of earthquakes. Hector was a foundation member of the Council and Chancellor of the University of New Zealand, and he was knighted in 1887. All these and a number of various other achievements are the topic of separate chapters in Nathan’s book, and they underline the outstanding importance of a scientist whom a newspaper once called “a man who knows everything” (p. 12).

New Zealand Geological Timescale NZGT 2015/1

An updated age calibration of the New Zealand Geological Timescale, NZGT 2015/1, is presented. This incorporates local stage reassessments and recent international chronostratigraphic calibrations. Of the 54 locally defined New Zealand stages, the basal ages of 17 have undergone changes in age of 1% or more since NZGT 2004 (three since NZGT 2012). Some intervals of Permian and Cretaceous time remain unrepresented by local New Zealand stages.

New Zealand Geology

New Zealand is renowned for its diverse geology and dynamic tectonic setting astride an active segment of the boundary between the Pacific and Australian plates. New Zealand is an emergent fraction (5%) of the largely submerged 'continent' of Zealandia which is half the size of Australia. Zealandia is comprised mainly of continental crust but because it is less than 30 km thick, it is largely below sea level. Zealandia's origins relate to eastern Gondwanaland from which it rifted during the Late Cretaceous to early Cenozoic, with formation of the Tasman Sea floor. Continental Zealandia may be thought of as part of the Australian/Gondwanaland mineral estate, and it is rich in natural resources. However, it was stretched and thinned for 100 Myr, culminating in the Eocene with development of the modern plate boundary. New Zealand largely owes its emergence to plate collision processes within the past 25 Myr.

In Memorium : Dr. Joan Wiffen (1922–2009)

“You can’t find fossils in the Mangahouanga by prospecting the mountain slopes.” I looked up. She wasn’t kidding. Dense, thick, tropical rainforest covered every inch of the mountain sides, right down to the edges of creeks, streams and rivers. “Instead…”, the little white-haired lady said, “…you walk up the creeks and streams and look for fossils in the gigantic concretions that have rolled down the mountain slopes and collected in the valley bottoms.” I looked for the hip-waders and rubber boots. There weren’t any to be seen. In the next split-second, just like she had done for the last thirty years of her life, the 77 year-old matron of New Zealand vertebrate paleontology, Commander, Order of the British Empire (CBE), Gold Medal winner of the New Zealand Geological Survey, “Dragon Lady” Dr. Joan Wiffen, turned, hitched up her slacks a bit, gripped her rock hammer, and walked into Mangahouanga stream, headed upstream. Almost immediately, she bent down, grabbed a small concretion from the creek bottom, smacked it …

Tectonic significance of ductile deformation in low-grade sandstones in the mesozoic Otago subduction wedge, New Zealand

This study demonstrates how ductile strain measurements can determine the tectonic evolution of a large and long-lived subduction wedge. We provide a synthesis of the geology of the South Island of New Zealand, with an emphasis on a wedge tectonics perspective that contrasts with a traditional view that interprets New Zealand geology in the context of terrane collision and accretion. We argue that the Otago subduction wedge evolved in a steady fashion throughout its 290 to 105 Ma history in response to accretion of trench-fill and abyssal-plain sediments, and slow erosion of a subaerially-exposed forearc high. Maximum temperatures for rocks in the flanks of the forearc high were no greater than 150 to 300 °C, with solution mass-transfer active as the dominant ductile mechanism. The 54 studied samples provide information about the absolute ductile strains acquired all along their flow-path, from the site of accretion to exhumation in the forearc high. We use tensor-averages to estimate strain at a regional scale. These show plane-strain uniaxial flattening, given that the tensor-averages for <i>S_y</i> and <i>S_x</i> are close to one. On average, <i>S_z</i> is approximately 0.77, and this is balanced by a mass loss of about 23 percent. The average Z direction is sub-horizontal in the prowedge and moderately plunging in the retrowedge, a difference attributed to spatial variations in the mode of accretion. We infer that rocks presently in the pro-side of the Otago high were sourced by frontal accretion, and those in the retro-side were underplated. This result highlights the important role of accretion in determining the style of within-wedge deformation, and also demonstrates the benefit of using a tensor-averaging approach to examine regional strain.

Alexander McKay and the awatere fault, New Zealand: Ground rupturing and large‐scale horizontal displacement

In 1888–89, Alexander McKay, Assistant Geologist of the New Zealand Geological Survey, defined the Awatere Fault, one of the four major dextral strike‐slip faults in the Marlborough area that constitute the Australia‐Pacific plate boundary in northeastern South Island of New Zealand. McKay began tracing and describing active faulting in New Zealand in 1885 and his observations were fundamental in clarifying the relationship between superficial earthquake‐rents or fissures and faults, and that faults have long displacement histories. Along the Awatere Fault, he determined the nature of the faulted contact between late Miocene, Cretaceous to early Tertiary rocks and Mesozoic greywacke, vertical displacement of Quaternary alluvial gravel surfaces, and confirmed evidence for repeated movement on the fault. For the first time anywhere in the world, McKay's work on the Awatere Fault suggested the possibility of large‐scale strike‐slip displacement (of 29–32 km). McKay took several photographs of the Awatere Fault using a telephoto lens that he had invented, and which is explained.

2008 CUSHMAN AWARD WINNER, GEORGE H. SCOTT

Fifty years ago, in 1957, George Scott took up his first and only professional appointment, as a foraminiferal micropaleontologist at the New Zealand Geological Survey in Lower Hutt. Although now retired from paid employment, he still goes in to work to undertake foraminiferal research nearly every day. Thus, George is now the Southern Hemisphere’s most experienced foraminiferal research scientist. Throughout his career, he has been a world leader in studies on the evolution of foraminifera using biometrics, statistical evaluation and quantification of foraminiferal data, and evolution of planktic foraminifera with emphasis on Southern Hemisphere temperate lineages. George Scott, along with the late Norcott Hornibrook and late Graham Jenkins, played the major role in elevating Cenozoic foraminiferal biostratigraphy of NZ to the international reputation it now enjoys. George Scott spent his childhood in the small rural district of Riwaka, in New Zealand’s South Island. He was dux (valedictorian) at Motueka High School in 1949, and gained a master of arts in geomorphology (1954) and a master of science in micropaleontology (1957, The Distribution of Fossil Foraminiferal Populations) from the University of Canterbury, NZ. From there, he joined Norcott Hornibrook as a foraminiferal micropaleontologist in the NZ Geological Survey and in the same year married fellow Survey paleontologist Anne Boreham. George and Anne have three children, Andrew, Michael and Pania, all now grown up and married. George has always kept fit. In earlier years, he would be found most lunch times at the local pool swimming laps. George has always shared the family car with Anne and thus his usual mode of transport to work and around the Hutt Valley is by bicycle. Nowadays …

Bones and words in 1870s New Zealand: the moa-hunter debate through actor networks

AbstractThe paper describes an episode in New Zealand science commonly referred to as the moa-hunter debate. In the 1870s the geologist and curator of the Canterbury Museum Julius Haast put forward a proposal that a race distinct from the indigenous Maori hunted the giant flightless birds known as moa to extinction. James Hector, director of the New Zealand Geological Survey and manager of the New Zealand Institute, rejected this proposal and challenged Haast in what would become a bitter fight. Because moa remains in the form of semi-fossilized bones, eggshells and occasionally preserved feathers and skin were important in the debate, the paper will use the analytical method of actor-network theory (ANT) to reopen it. The paper thus provides an opportunity to study the strengths and weaknesses of ANT as a form of analysis. This analysis emphasizes a number of interesting points about the moa-hunter debate, including the ability of human actors to manipulate the meaning of common terms in order to create new theories, in this case Haast's theory of an earlier indigenous race in New Zealand. Though dismissed at the time, this was a belief that has lasted in alternative forms to the present.

George Leslie Adkin (1888-1964): glaciation and earth movements in the Tararua Range, North Island, New Zealand

Abstract In the northern hemisphere the broad extent of glaciation had been mostly accepted by the start of the twentieth century, but in New Zealand at that time even the general picture of glaciation was uncertain. Julius von Haast had established that in the South Island the glaciers had extended out considerably from the Southern Alps, but the extent of glaciation in the North Island was unknown. Two rival viewpoints were put forward in 1909. James Park thought that there was a widespread ice sheet, which covered the South Island, Cook Strait and much of the North Island; Patrick Marshall thought that the extent of ice was much less, and argued that much of Park's evidence was spurious. The argument was ‘somewhat resolved’ by a young amateur geologist, Leslie Adkin, who showed that glaciation in the North Island was at most modest, and largely confined to the uppermost part of the main axial ranges. Adkin was a farmer and had no university education, but he published nearly 40 articles in scientific journals on topics as varied as Maori archaeology, and glacial and tectonic geomorphology. This article examines the evidence he adduced for the occurrence of a limited Pleistocene glaciation in the Tararua Range in the south of the North Island, and considers the role of the amateur in New Zealand geology.

Nineteenth-century observations of the Dun Mountain Ophiolite Belt, Nelson, New Zealand and trans-Tasman correlations

Abstract The Nelson Mineral Belt, part of the Dun Mountain Ophiolite Belt of Permian age, in the north of the South Island of New Zealand, was the subject of intense interest soon after the European settlement of New Zealand owing to the discovery of copper and chromite mineralization. The first geologist to survey the Mineral Belt in east Nelson was Thomas Ridge Hacket ( c . 1830–1884), who arrived from Britain in 1857, although he was primarily interested in the mineralization. The first scientific description of the belt followed the visit in 1859 of the geologist Ferdinand von Hochstetter (1829–1884) of the Austrian Geological Survey who regarded the belt as a sill. He recognized that Dun Mountain was not serpentinite, like the rest of the belt, but an olivine-rich rock that he named dunite. von Hochstetter tentatively considered that thick mafic rocks of the Brook Street Volcanics, that were then considered to be intrusives rather than sedimentary, may have been a correlative of the Mineral Belt. Between the belt and the Brook Street rocks he mapped the Wooded Peak Limestone and Maitai Slates. von Hochstetter tentatively assigned a Mesozoic age to all of the above rocks and for nearly 100 years Mesozoic sedimentary rocks in many parts of New Zealand were regarded as a correlative of the Maitai Slates. Both Hacket and von Hochstetter confirmed an abundance of chromite in the Mineral Belt, a finding that resulted in the building of New Zealand's first railway. Mining was short-lived but hopes were raised that gold might be found following Hacket's move to Queensland in the late 1860s. He recognized that the Gympie gold-fields had many similarities with Dun Mountain and reasoned that east Nelson might also be auriferous. This was taken up by men in Nelson such as Sir David Monro (1813–1877) and William Wells (1810–1893) who were keen geological observers, and by Monro's son in law Dr, later Sir James, Hector (1834–1907) who was director of the New Zealand Geological Survey. In 1870, Hector arranged for Edward Heydelbach Davis (1845–1871) to undertake a detailed examination of the Permo-Triassic rocks of east Nelson. Davis, like Hacket, regarded the Mineral Belt as metamorphosed Maitai rocks. As well as demonstrating that the east Nelson rocks did not contain economic concentrations of gold, copper or chromite, Davis showed that they were distinct from what had been thought to be similar rocks in the Coromandel gold-fields in North Island of New Zealand. This was the first, if not fully appreciated, step to limit the Maitai rocks. Hacket's correlation of the Gympie and Dun Mountain rocks was forgotten until the advent of plate tectonics. The various major rock units in Nelson are now recognized as terranes that accumulated as a result of convergent plate tectonics along the Mesozoic margin of Gondwanaland.

New Zealand's Geological Foundations

New Zealand is a fragment of Gondwana that, before Late Cretaceous sea floor spreading, was contiguous with Australia and Antarctica. Only about 10% of the area of continental crust in the wider New Zealand region (Zealandia) is emergent above sea level as the North and South Islands. No Precambrian cratonic core is exposed in onland New Zealand. The Cambrian to Early Cretaceous basement can be described in terms of nine major volcano-sedimentary terranes, three composite regional batholiths, and three regional metamorphic-tectonic belts that overprint the terranes and batholiths. The terranes (from west to east) are: Buller, Takaka, Brook Street, Murihiku, Maitai, Caples, Bay of Islands (part of former Waipapa), Rakaia (older Torlesse) and Pahau (younger Torlesse). The western terranes are intruded by three composite batholith (>100 km 2) sized belts of plutons: Karamea-Paparoa, Hohonu and Median, as well as by numerous smaller plutons. Median Batholith (including the Median Tectonic Zone) is a recently-recognised Cordilleran batholith that represents the site of subduction-related magmatism from ca. 375–110 Ma. Parts of the terranes and batholiths are variably metamorphosed and deformed: Devonian and Cretaceous amphibolite-granulite facies gneisses are present in Buller, Takaka, Median and Karamea-Paparoa units; Jurassic-Cretaceous subgreenschist-amphibolite facies Haast Schist overprints the Caples, Bay of Islands and Rakaia Terranes; Cretaceous subgreenschist facies Esk Head and Whakatane Mélanges bound the Pahau Terrane. In the South Island, small areas (<5 km 2 total) of Devonian, Permian, Triassic and Jurassic Gondwana sequences have been identified. In the North Island a widespread Late Jurassic overlap sequence, Waipa Supergroup (part of former Waipapa Terrane), has recently been proposed.

Book review

Cenozoic Mollusca of New Zealand by A. G. Beu and P. A. Maxwell, with drawings by R. C. Brazier. New Zealand Geological Survey Paleontological bulletin 58 (DSIR Geology & Geophysics, P.O. Box 30 368, Lower Hutt, New Zealand) 1990. 500 p. Paperback, 210 X 295 mm (NZ/US$ 140.00). ISSN 0114–2283.