Brook Street Research Articles

DEM Computation of Flood Catchment Areas: Determining the Run-off and Maximum Discharge Time of Concentration in Uyo Urban

Rainfall runoff modelling is a vital and an essential paradigm in flood risk management. This research sought to determine the run-off and maximum discharge time of concentration (TC) in Uyo Urban to help facilitate adequate and proper flood risk and management plan in the area. The topographic map and 3D surface of the catchment area were generated and the rational method employed to determine the time of concentration of runoff as well as the maximum discharge while Hydrology extension in ArcGIS 10.3 was used to model the river basin from DEM and identify locations. Detailed analysis of 39 years (1977-2015) rainfall data was recorded to determine inter-annual variability, monthly distribution pattern, mean total annual rainfall, mean maximum daily rainfall and standardized anomaly index (SAI). The computed discharge was calculated. The results of the analyses indicate a total discharge of 1573.54m3/s and takes approximately 40 minutes of runoff time evident of prolonged rainstorms in areas like IBB Avenue as opposed to the short-lived rainfalls that causes flash floods in areas like Brook Street. This means that it takes a longer time of about 2 km to travel to the analysed site to cause flood. The study recommends the need for creation of more risk awareness and flood warning signs to further educate the people.

Sediment provenance in the Murchison and Maruia basins, Aotearoa/New Zealand: a record of Neogene strike-slip displacement, convergence, and basement exhumation along the Australian–Pacific plate boundary

ABSTRACT The Murchison and Maruia basins are situated on the Australian Plate adjacent the Alpine Fault, an ideal place to study Cenozoic Australian–Pacific plate boundary evolution. Sandstone provenance was investigated using petrographic and detrital zircon U–Pb geochronologic methods and primarily varies geographically. Secondary up-section variation tracks spatiotemporal changes in basement exhumation. Eocene–middle Miocene western Murchison Basin sandstone is arkosic, derived locally from Devonian–mid-Cretaceous granitoids. Early Miocene–?Pliocene eastern Murchison and Maruia basin sandstone is lithic-/plagioclase-rich, reflecting a mixed provenance: proximal Carboniferous–mid-Cretaceous granitoids, and distal mid-Cretaceous Median Batholith and Permian–Triassic Eastern Province metasedimentary sources in the Pacific Plate. This confirms early Miocene Pacific Plate exhumation during initial Alpine Fault evolution began in northern Fiordland/western Otago but the contrast between eastern and western Murchison Basin indicates limited westward sediment dispersal. Higher proportions of Brook Street Terrane (BST) detrital zircon in middle Miocene eastern Murchison Basin sandstone suggests accelerated Pacific Plate exhumation at c. 15 Ma. By c. 10 Ma, the eastern Murchison Basin BST source had switched to the Australian Plate due to Waimea–Flaxmore fault reverse reactivation and dextral plate boundary strike-slip displacement, which by the late Miocene/Pliocene led to Rakaia Terrane-affinity Haast Schist replacing Caples Terrane as the main Maruia Basin sediment source.

Age and structure of the Permian Brook Street Terrane, Takitimu Mountains, New Zealand

ABSTRACT We use a recently completed airborne magnetic and gamma-ray spectrometric survey, and new U/Pb and 40Ar/39Ar age determinations, to revise and clarify several aspects of Brook Street Terrane geology in the Takitimu Mountains. Steeply dipping and homoclinal Permian Takitimu Subgroup formations defined in the central part of the range can, with moderate confidence, be traced along strike to other parts of the range where they are more complexly folded and faulted. We report intrusion ages for three Brook Street plutonic suites: pyroxene-bearing White Hill Intrusives (306-270 Ma, U/Pb zircon), amphibole-bearing Mackinnon Peak Intrusives (261 ± 1 Ma, 40Ar/39Ar amphibole), and shoshonitic Wether Hill Dikes (254 ± 1 Ma, 40Ar/39Ar plagioclase). Geological relationships between these intrusions and the host Takitimu Subgroup reinforce the Early Permian age of the latter, which is distinct from the overlying Late Permian Productus Creek Group. The Wether Hill Dikes mark the cessation of igneous activity in the Brook Street Terrane at c. 254 Ma. A large (n = 499) dataset of detrital zircon U/Pb ages from the nonmarine Jurassic Barretts Formation confirms a local Median Batholith-Tuhua Intrusives provenance and supports a post-Permian fore-arc tectonic setting along the Gondwana margin.

Continental Crustal Growth Processes Revealed by Detrital Zircon Petrochronology: Insights From Zealandia

AbstractEstablishing spatial, temporal, and geochemical relationships between magmatism and the broader tectonics of accretionary orogens is important for understanding continental crustal growth processes. Here we reconstruct the Paleozoic and Mesozoic evolution of the active continental margin of Zealandia (eastern Gondwana), using a combination of detrital zircon geochronology, trace element geochemistry and Hf isotope data. We find that zircon grains dated 360–160 Ma from New Zealand are characterized by εHfi (+15 to +2) and trace element compositions typical of predominantly juvenile magmatic sources. In contrast, the εHfi (+15 to −5) and trace element compositions of detrital zircon grains dated 245–140 Ma from New Caledonia reflect a mix of juvenile and evolved crustal sources. Secular trends in trace element and Hf isotope compositions of zircon grains suggest that magmatism and continental crustal growth in Zealandia during the Devonian‐Cretaceous were controlled by switches from trench advance to trench retreat. Orogenesis and crustal growth were controlled by a long‐lived westward dipping subduction system, which during the Permian‐Triassic, was intermittently affected by distinct phases of arc accretion (e.g., of the Brook Street intraoceanic arc) and orogenesis (e.g., driven by trench advance). These phases of orogenesis coincided with the Gondwanide Orogen (265–230 Ma), which might have been controlled by a plate‐scale reorganization event following the final assembly of Pangea supercontinent.

Contemporaneously emplaced submarine volcaniclastic deposits and pillow lavas from multiple sources in the island arc Brook Street Terrane, Southland, New Zealand

ABSTRACT Volcaniclastic and coherent volcanic rocks of the Permian island arc Brook Street Terrane crop out along the Southland coast, New Zealand, near Riverton. Extensive along-strike exposures reveal lateral variations in these submarine deposits and provide a rare opportunity to examine deposits of an arc environment within a thin slice of time. We describe pillow lavas, dikes, hydroclastic breccias, tuffs, lapilli tuffs and argillites, all hydrothermally altered and metamorphosed to prehnite-pumpellyite facies. Trace element geochemical data indicate multiple primitive island arc to MORB-like magma sources. Two separate volcanic centres apparently tapped different mantle domains in a source region transitional between the arc and back-arc. The centres’ proximity and inferred small sizes suggest they were satellite vents of a larger arc volcano. Tuff and lapilli tuff were formed as hyaloclastite during eruption of pillow lava, and redeposited by subaqueous mass flows. Peperitic contacts indicate that the lavas intruded unconsolidated volcaniclastic deposits. We infer that hydroclastic fragmentation associated with pillow emplacement produced debris that was then intruded by later pillows, with local peperite formation, as eruption persisted. The hydroclastic debris from these satellite vents was resedimented in turbidite fans with channels, and periodic turbidity currents delivered fine-grained material from the volcano’s main vent.

‘Master of the Orchester with a Sallary’: Handel at the Bank of England

Abstract The discovery of an account held by Handel at the Bank of England in 1721 offers new documentary information about his financial transactions and evidence for his residence before the move to Brook Street. Careful consideration of the circumstances surrounding this account leads to a reinterpretation of Handel’s short-lived accounts with the Royal African Company in 1720 and sheds light on Handel’s South Sea Annuities account (1723–32). An analysis of the South Sea Annuities account clarifies its origin and explains its pattern of credits and withdrawals, suggests the exact salary Handel received from the Royal Academy of Music as ‘Master of the Orchester’, and indicates that the financial arrangements for Handel’s salary that had been in place from the inception of the Academy were continued at the beginning of the ‘Second Academy’.

Origin of dispersed Permian–Triassic fore-arc basin terranes in New Zealand: Insights from zircon petrochronology

Permian–Triassic fore-arc basin terranes are exposed in New Zealand, but their original positions and tectonic configurations along the eastern Gondwanan margin are not fully understood. To better constrain late Paleozoic and Mesozoic reconstructions, we investigated the provenance of Permian–Triassic marine sandstone units from the Dun Mountain-Maitai Terrane (Maitai Group) and the Kaka Point Structural Belt (Willsher Group). The recognition of abundant volcanic lithic fragments in the sandstone samples, combined with the pattern of detrital zircon ages (unimodal to bimodal 280–240 Ma age distribution), demonstrate that the upper Permian to Middle Triassic volcaniclastic successions were derived from a proximal arc source. The detrital zircon age spectra match magmatic pulses in the adjacent Tuhua Intrusives (Median Batholith), a conclusion similar to that recently proposed for the Brook Street Terrane (Grampian Formation) and Murihiku Terrane (Murihiku Supergroup). Trace-element data from the dated zircon grains provide further evidence for a Median Batholith source and cross-terrane provenance links. The data indicate that 275–230 Ma zircon grains from the Maitai Group, Willsher Group, and Murihiku Supergroup were derived from a common magmatic source, and that the late Permian Longwood Suite (261–252 Ma) in the Median Batholith was a source region for these terranes. Based on the cross-terrane provenance links, we suggest that the Brook Street and Murihiku terranes were deposited in the proximal part of a fore-arc basin, whereas the Dun Mountain-Maitai Terrane represents the distal part of the same basin. Sedimentation in the Maitai Group ceased during the Middle Triassic (∼238 Ma), likely in response to a period of orogenesis at 235–230 Ma (Gondwanide Orogeny) that is widely recognized throughout the southwest Pacific.

Reconnaissance composition of river sand from northern South Island, New Zealand: a modern analogue for southern Taranaki Basin

ABSTRACTThe composition of 20 modern sand samples (18 streams, one beach, and one lakeshore) collected from the northern South Island provide a dataset for assessing detrital signatures of Paleozoic-Mesozoic basement terranes that may have served as sediment sources for reservoir sandstones in the Taranaki Basin. Non-plutonic terranes produce lithic-rich sand dominated by metamorphic fragments. Samples derived from erosion of the Rakaia and Caples terranes are more quartz-rich than the other non-plutonic terrane samples. Sand from the Dun Mountain-Maitai and Brook Street terranes has the lowest quartz content and is further distinguished by detrital serpentine. Pervasive pumpellyite-bearing metamorphic lithic fragments characterise the Caples, Dun Mountain-Maitai and Brook Street terranes. Feldspar is rare in Eastern province terrane sand. Sand from the Median Batholith tends to have less quartz than sand from the Karamea Batholith and a higher percentage of plagioclase, while sand from the Karamea Batholith has a higher proportion of potassium feldspar. Petrographic analyses were compared with published reports describing the composition of offshore sandstone reservoirs to evaluate their likely provenance.

Where is the boundary between New Zealand’s western and eastern provinces? A case study in describing terrane relationships using cladistic methods.

ABSTRACTA cladistic analysis of 21 geological characters taken from the literature is used to determine the relationship between the Drumduan Terrane, Takaka Terrane (Western Province), and Brook Street Terrane (Eastern Province) of Nelson, New Zealand. We present the analysis as a case study to illustrate the utility of a cladistic approach to describing terrane relationships. The results of the analysis support the placement of the Drumduan Terrane as the eastern boundary of the Western Province providing the Pepin Group and Echinus Granite are the basement of the overlying Marybank Formation sediments rather than being tectonically juxtaposed. The importance of establishing whether the Drumduan Terrane and its proposed correlatives in Fiordland and Stewart Island are part of the Western or Eastern Province is that natural groupings can be identified and tectonic reconstructions can be free of artifice.

Chapter 2 The path to understanding the central terranes of Zealandia

Abstract This chapter traces the history of understanding the central terranes of New Zealand: Drumduan, Brook Street, Murihiku, Dun Mountain–Maitai and Caples. The terranes, mostly exposed in the South Island, are named from stratigraphic units of Late Paleozoic–Late Mesozoic age, including the Murihiku Supergroup, Brook Street Volcanics and Maitai groups, and the Dun Mountain ophiolite. European geologists in the mid-nineteenth century determined the stratigraphy of these rocks in the extremities of the island but in the succeeding half-century much effort was devoted to understanding widespread poorly fossiliferous ‘greywackes’: the ‘Maitai Controversy’. This was resolved in 1917 by palaeontology and the recognition of major faulting. In the 1940s the Alpine Fault, with an apparent 460 km dextral offset of the rocks at either end of the island, was recognized. In the following two decades, New Zealand was interpreted in terms of the geosynclinal hypothesis and then paired metamorphic belts. With plate tectonics, the basement rocks were assigned to terranes with the implication of being conveyed over considerable distances. The identification of source areas, coupled with the definition of the Cordilleran Median Batholith, has progressed the understanding of the present arrangement of the central terranes in the New Zealand part of Zealandia.

Chapter 13 Permian–Triassic felsic tuffs in South Island, New Zealand: significance for oceanic and active continental margin subduction

Abstract Felsic tuffs play an important role in the Permian–Triassic geology of the Eastern Province in South Island. In the Brook Street Terrane, primary felsic tuff is minor in the south (e.g. Takitimu Mountains) but abundant in the north (Grampian Formation, Nelson area). Felsic fallout tuff dominates one interval of the Maitai Group (Early Triassic Kiwi Burn Formation), south of the Alpine Fault, but is otherwise mainly redeposited by gravity flows. The Murihiku Terrane is characterized by two main intervals of felsic fallout tuff, the Middle Triassic Gavenwood Tuffs and the Late Triassic Bare Hill Tuff Zone, south of the Alpine Fault (e.g. Hokonui Hills and south Otago coast). Counterparts north of the Alpine Fault (Richmond Group) are mainly reworked, with terrigenous admixtures. Tuffaceous sediments are also abundant in the late Middle–early Late Triassic Willsher Group (south Otago coast). Based on combined field, petrographical, semi-quantitative X-ray diffraction (XRD) and chemical evidence, the felsic tuffs of the Brook Street Terrane in the south are interpreted as small-scale eruptions of fractionated oceanic-arc-type magmas. In contrast, the Triassic felsic tuffs of the Murihiku Terrane, Willsher Group and Maitai Group erupted violently and episodically in proximal to distal segments of the SE Gondwana continental margin.

Chapter 15 Construction of a Paleozoic–Mesozoic accretionary orogen along the active continental margin of SE Gondwana (South Island, New Zealand): summary and overview

Abstract The Western Province is a fragment of the c. 500 Ma SE Gondwana active continental margin. The Eastern Province is a terrane assemblage, which is partly stitched by the Median Batholith. Fragments of the batholith are preserved in the adjacent Drumduan and Brook Street terranes. Permian arc magmatism of the Brook Street Terrane involved both oceanic and continental margin settings. The Permian ( c. 285–275 Ma) supra-subduction zone Dun Mountain ophiolite records subduction initiation and subsequent oceanic-arc magmatism. The Permian Patuki and Croisilles melanges represent detachment of the ophiolitic forearc and trench–seamount accretion. The Murihiku Terrane, a proximal continental margin forearc basin, received detritus from the Median Batholith (or equivalent). The south coast, Early–Late Triassic Willsher Group is another proximal forearc basin unit. The sediments of the Dun Mountain–Maitai Terrane (Maitai basin) represent a distal segment of a continental margin forearc basin. The Caples Terrane is a mainly Triassic trench accretionary complex, dominantly sourced from a continental margin arc, similar to the Median Batholith. The outboard (older) Torlesse and Waipapa terranes are composite subduction complexes. Successively more outboard terranes may restore farther north along the SE Gondwana continental margin. Subduction and terrane assembly were terminated by collision (at c. 100 Ma), followed by rifting of the Tasman Sea Basin.

Chapter 3 Biostratigraphic age review of New Zealand's Permian–Triassic central terranes

Abstract This contribution considers the fossil content of the three Eastern Province ‘central’ terranes discussed within this Memoir, namely the Brook Street Terrane, the Dun Mountain–Maitai Terrane and the Murihiku Terrane, and reviews the evidence and/or arguments for the current interpretation of their age ranges as determined from fossils. It also briefly considers the Permian–Triassic record of the Western Province. There has been limited new palaeontological discovery in the past few decades but there has been significant new taxonomic and biostratigraphic analysis of New Zealand Permian faunas in light of new research in eastern Australia. This enables refinement of age correlations and greater confidence in the age significance of the New Zealand Permian record.

About this title - Paleozoic–Mesozoic Geology of South Island, New Zealand: Subduction-related Processes Adjacent to SE Gondwana

This volume presents a set of research papers that provide new data and interpretations of the Permian–Triassic terranes of SE Gondwana, now exposed in South Island, New Zealand. Following an introduction for general readers, a historical summary and a review of biostratigraphy, the individual papers primarily focus on the Permian magmatic arc of the Brook Street Terrane, the classic Permian Dun Mountain ophiolite and the Permian–Triassic Maitai Group sedimentary succession. The new results emphasize the role of subduction and terrane displacement adjacent to the Permo-Triassic Gondwana margin, and present fundamental insights into three crustal processes: subduction initiation, supra-subduction zone oceanic crust genesis and forearc basin evolution. The volume concludes with a wide-ranging summary and synthesis of the regional Cambrian to Early Cretaceous tectonostratigraphy of New Zealand's South Island in relation to the wider areas of Zealandia, East Australia and West Antarctica. The volume will interest geoscientists, including stratigraphers, sedimentologists, palaeontologists, igneous petrologists, geochemists, geochronologists and economic geologists, and is aimed at professional geologists and advanced students of geology.

Chapter 12 A 251 Ma diorite clast from a Maitai Group conglomerate and a c. 259 Ma microdiorite sill intruding the Productus Creek Group, Southland, New Zealand: note

Abstract We present the results of U–Pb dating of zircons of two Late Permian igneous rocks from the Dun Mountain–Maitai and Brook Street terranes of New Zealand's South Island. A conglomerate clast of hornblende diorite from the Early–Middle Triassic Stephens Subgroup, Maitai Group, gives an age of 251.1 ± 1.6 Ma. A sample of hypabyssal andesite–microdiorite (Weetwood Formation) that intrudes the Late Permian Productus Creek Group of the Brook Street Terrane gives an age of 258.8 ± 7.9 Ma. The intermediate and subalkaline geochemistry of the two samples is not distinctive of specific tectonic settings, but their ages match plutons of the I-type, subduction-related Longwood Suite of the nearby Median Batholith. Assuming that correlation with the Longwood Suite is correct, the Weetwood sample increases the known areal extent of intrusion of the Longwood Suite; and the Stephens Subgroup Formation clast is consistent with a detrital link between Gondwana and the Dun Mountain–Maitai Terrane by the Middle Triassic. However, because of uncertainties regarding the timing of magmatism along other parts of the Gondwana margin, the data in this paper do not establish any specific provenance links.

Chapter 4 Geological development and regional significance of an oceanic magmatic arc and its sedimentary cover: Permian Brook Street Terrane, South Island, New Zealand

Abstract The c. 450 km-long Brook Street Terrane (pre-Alpine Fault displacement) sheds light on processes of arc magmatism and related sedimentation. A very thick (up to 15 km) succession accumulated south of the Alpine Fault in the Takitimu Mountains during the Early Permian. Predominant arc-flank talus is intercalated with basic extrusive and intrusive igneous rocks. Volcaniclastic sediments mainly accumulated by mass-flow and turbidity current processes. The sediments were mostly derived from differentiated, arc-core, basaltic–andesitic rocks, contrasting with less evolved arc-flank flows and minor intrusions. Some igneous rocks are mildly enriched, supporting an extensional back-arc setting. After volcanism ended, Middle–Late Permian mixed carbonate–volcaniclastic gravity-flow deposits were derived from a non-exposed carbonate platform. Other volcanogenic successions in the south (Bluff, Riverton) represent smaller eruptive centres. In contrast, north of the Alpine Fault (e.g. Nelson), volcanism began with mostly felsic tuffaceous gravity-flow deposits, followed by extrusion/intrusion of clinopyroxene-rich, primitive magmas, related to arc rifting, and ended with an accumulation of a mixed basic–felsic volcaniclastic forearc apron. Taking account of regional comparisons, the Early Permian arc is interpreted as having formed adjacent to Gondwana (on accreted or trapped oceanic lithosphere), whereas the lithologies north of the Alpine Fault represent contrasting Late Permian continental arc magmatism.

Provenance of Jurassic sandstones in the Rakaia Terrane, Canterbury, New Zealand

ABSTRACTDetrital zircon U–Pb and muscovite 39Ar/40Ar ages from sandstones in the fluviatile to shallow marine mid-Jurassic Clent Hills Group and Wakaepa Formation of mid-Canterbury, South Island, New Zealand, show characteristic patterns that demonstrate a derivation from local Permian (and possibly Triassic) basement rocks of the Rakaia Terrane (Torlesse Composite Terrane). In the Clent Hills and Wakaepa age data sets, Permian to Triassic zircons form the major age groups, 34% and 58% respectively, but early Paleozoic (20% and 10%) and Precambrian (32% and 28%) zircons also form minor groups. The Precambrian zircons are mainly late Mesoproterozoic and late Neoproterozoic. The muscovite 39Ar/40Ar age patterns reveal no Precambrian ages and the majority (48%) again fall in the Permian–Triassic age range. We postulate a local sediment source in the predominantly Permian Rakaia Terrane basement during Jurassic time, when the terrane was a deformed and stabilised upland block extending principally to the east. This was thus a convergent plate margin against which contemporary marine sedimentary basins developed and consolidated as the Kaweka Terrane (Torlesse Composite Terrane). The provenance of the Canterbury Jurassic cover rocks contrasts markedly with Jurassic-age cover rocks in the Brook Street Terrane. The latter show an almost unimodal pattern reflecting a volcaniclastic environment well-removed from continental sediment sources.

Cladistic methods as a tool for terrane analysis: a New Zealand example

ABSTRACTA cladistic analysis of New Zealand's basement terranes was conducted using 44 present/absent characters that were derived from the literature for a broad range of geological characters, including zircon age profiles, clastic source, metamorphic grade and igneous petrology. The analysis resulted in a classification showing that both the Eastern and Western provinces are natural groupings. Two monophyletic clades (natural historical groupings) were identified within the Eastern Province: a Central Arc clade of South Island terranes (Maitai/Dun Mountain, Murihiku and Brook Street), and the younger greywacke terranes plus the North Island Murihiku Terrane. The Rakaia and Kaweka terranes of the older Torlesse are basal to (less derived than) the Central Arc and Eastern Province younger greywacke terranes. Although cladistic methodologies have been developed for biological systems, these results demonstrate a proof of principle for their application to terrane analysis.

Ophiolites and Intra‐Oceanic Island Arc Assemblages of Eastern Australia, New Caledonia and New Zealand

Throughout the Phanerozoic the eastern margin of Gondwana and related fragments such as New Caledonia and New Zealand that are now dispersed from it grew through the addition of ophiolites and associated intra‐oceanic island arc assemblages. Exactly how and why this occurred remains controversial with two main competing models referred to as either ‘quantum'or‘accordion’ tectonics. The quantum model envisages continental growth through the additional of discrete intra‐oceanic assemblages analogous to contemporary tectonic settings in Taiwan, Timor and Papua New Guinea (Aitchison and Buckman, 2012). The alternative regards eastern Australia as the type example of a different style of convergent plate margin referred to as an ‘extensional accretionary orogeny’ (Collins, 2002).The oldest Phanerozoic ophiolites and intra‐oceanic island arc assemblages are of Cambrian age and are widely reported from the Lachlan Fold Belt in the eastern Australian states of Victoria and NSW (Spaggiari et al., 2003; Greenfield et al., 2011). Similar rocks are also known from Mount Read in Tasmania (Berry and Crawford, 1988; Crawford and Berry, 1992; Mulder et al., 2016), the Weraerai terrane and its correlatives in the New England orogen further east in northeastern NSW (Aitchison et al., 1994; Aitchison and Ireland, 1995) and Queensland, the Takaka terrane in NW Nelson, New Zealand (Münker and Cooper, 1999) and the Bowers terrane in Northern Victoria Land, Antarctica (Weaver et al., 1984; Münker and Crawford, 2000; Rocchi et al., 2011; Palmeri et al., 2012).The Late Ordovician saw the development of the intra‐oceanic Macquarie island arc (Glen et al., 1998; Glen et al., 2007). This system contains important economic mineral deposits. The way in which these arc rocks developed and were juxtaposedagainst a surrounding suite of Lachlan Fold Belt, eastern Australia remains the subject of investigation (see Aitchison and Buckman, 2012 for discussion). In a similar area, enigmatic rocks of the Tumut ophiolite also crop out (Graham et al., 1996; Belousova et al., 2015).Further to the east in the New England orogeny Siluro‐Devonian rocks of the Gamilaroi terrane and it's along strike correlatives near Mt Morgan in Queensland represent another intra‐oceanic island arc assemblage emplaced onto the Gondwana margin in the Late Devonian (Aitchison and Flood, 1994; Offler and Murray, 2011).The Late Carboniferous‐Permian saw development of significant intra‐oceanic island arc and ophiolitic complexes remnants of which crop out in New Zealand, eastern Australia, and New Caledonia. These include the Brook Street terrane (Spandler et al., 2005; McCoy‐West et al., 2014) and Dun Mountain Ophiolite Belt in New Zealand (Coombs et al., 1976; Stewart et al., 2016), the Gympie terrane in southeast Queensland (Waterhouse and Sivell, 1987; Sivell and Waterhouse, 1988) and the Koh terrane in New Caledonia (Meffre et al., 1996; Ali and Aitchison, 2002).The youngest on‐land association of ophiolitic and intra‐oceanic island arc rocks in the region is of Eocene age. Ultramafic rocks are well exposed in New Caledonia where they structurally overlie continental rocks of Gondwana margin affinity that, in the northeast of the island, have experienced eclogite facies metamorphism (Aitchison et al., 1995). The emplacement of these rocks was a widespread regional event with potentially correlative rocks exposed in Papua New Guinea (Parrot and Dugas, 1980) as well as Northland and East Cape in New Zealand (Whattam et al., 2005; Whattam et al., 2008).

Assessing the needs of older people in urban settings: integration of emotive, physiological and built environment data

Design of the built environment for navigability and walkability is an increasingly important aspect of urban planning. This focus derives in part from increasing interest in lifestyles and behaviours, including level of physical activity and health outcomes. Geographical information systems and virtual realities are playing a significant role in advancing this agenda: examples exist of integrating qualitative data (words about or visual images of places) and quantitative data (numerical descriptions of places). However, there remain opportunities for exploring alternative ways of linking different types of data (physiological measurements, emotional response, street walkability and urban design quality) to address issues of urban planning and renewal. Using a case study approach this paper explores the application of geographic information science and systems to participatory approaches in built environment planning with the aim of exploring older people's response to an unfamiliar urban environment. It examines different ways of combining temporally and spatial referenced qualitative and quantitative data. The participants in the study were a group of 44 older people (60+) from Swansea, Wales, who viewed a filmed walking route around Colchester, England. While viewing the film they gave an oral commentary and physiological readings were made, which have been integrated with primary data collected on the built environment along the walking route. Proximity and inverse distance weighting approaches for combining these datasets produce complementary results in respect of older people's physiological and emotive response to variation in the walkability and design quality of a walking route through an unfamiliar town centre. The results reveal participants experienced an elevated average heart rate close to Colchester Town railway station and expressed a comparatively negative emotional response to this location. Conversely participants experienced lower average heart rate, indicating reduced stress, in Brook Street where the overall Urban Design Quality score was relatively low.