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Mt. Taranaki is an andesitic stratovolcano in the western North Island of New Zealand. Its magmas show slab-dehydration signatures and over the last 200 kyr they show gradually increasing incompatible element concentrations. Source basaltic melts from the upper mantle lithosphere pond at the base of the crust (∼25 km), interacting with other stalled melts rich in amphibole. Evolved hydrous magmas rise and pause in the mid crust (14–6 km), before taking separate pathways to eruption. Over 228 tephras erupted over the last 30 kyr display a 1000–1500 yr-periodic cycle with a five-fold variation in eruption frequency. Magmatic supply and/or tectonic regime could control this rate-variability. The volcano has collapsed and re-grown 16 times, producing large (2 to >7.5 km3) debris avalanches. Magma intrusion along N-S striking faults below the edifice are the most likely trigger for its failure. The largest Mt. Taranaki Plinian eruption columns reach ∼27 km high, dispersing 0.1 to 0.6 km3 falls throughout the North Island. Smaller explosive eruptions, or dome-growth and collapse episodes were more frequent. Block-and-ash flows reached up to 13 km from the vent, while the largest pumice pyroclastic density currents travelled >23 km. Mt. Taranaki last erupted in AD1790 and the present annual probability of eruption is 1–1.3%.

The Palaeozoic–Mesozoic tectonic evolution of Central Asia, including the vast terrane collage that makes up Mongolia, has been a topic of considerable debate. The Oyut Ulaan Volcanic Group is a sequence of volcanic and sedimentary rocks in SE Mongolia that forms the southern part of the Devonian–Permian Saykhandulaan Inlier. Fieldwork traverses and mapping have established four distinct formations in the Oyut Ulaan Volcanic Group that record the nature of arc activity in part of the Central Asian Orogenic Belt during the Carboniferous. Physical volcanological and sedimentological characteristics of the four formations suggest three clear eruptive styles: (1) periodic andesite volcanism in an actively eroding arc setting that also contained large rivers and swamps; (2) highly effusive plateau andesite volcanism; (3) explosive rhyolitic effusion. Geochemical analyses of volcanic lithologies suggest that the group represents subduction-related, mature, continental arc volcanism. Geochemical results document an evolving magma system to which surface processes of the volcano-sedimentary model may be linked. Magma pulses and replenishments are identified from variations in chemostratigraphy. Newly obtained zircon ages from the volcanic succession fix its emplacement (eruption) at 323.0 ± 0.7 Ma (mid-Carboniferous or late Mississippian). A granite cobble from the lower part of the Oyut Ulaan Volcanic Group gives a U–Pb zircon age of 338.9 ± 0.4 Ma indicating that arc plutons were emplaced 10 Ma prior to the Oyut Ulaan volcanism and were eroded soon after. Our work provides timing constraints for final accretion and continental assembly in SE Mongolia, and also sheds light on the petrological development of a magmatic arc system within an evolving accretionary orogen.

The crust in southern Mongolia is part of the Central Asian Orogenic Belt, a vast accretionary orogen that records the opening and closure of the Palaeo-asian Ocean in the late Proterozoic to Palaeozoic. The crustal evolution of the region is revealed in basement inliers that also contain intrusion-related porphyry ore bodies that are important mineral exploration targets. The Saykhandulaan inlier in Southeast Mongolia is a Devonian–Carboniferous segment of island-arc crust, which is dominantly composed of extrusive and sedimentary lithologies, but which also contains the Oyut Ulaan I-type quartz-monzonite intrusion. A U–Pb zircon age for the Oyut Ulaan monzonite indicates emplacement at 330.0 ± 0.5 Ma. To the east of the Saykhandulaan inlier, intrusive complexes dominate the neighbouring Mandakh inlier. New ages are presented for four of these plutons; the Bronze Fox granodiorite (333.6 ± 0.6 Ma); the Narin Hudag monzonite (333.2 ± 0.6 Ma); the Shuteen quartz monzonite (325.5 ± 1.0 Ma); and the North Mandakh granite (292.3 ± 0.5). The intrusive bodies of the Saykhandulaan and Mandakh inliers have two distinct geochronological and geochemical associations: 1) mid-Carboniferous I-type monzonites that constitute the most easterly intrusive expression of the Southern Mongolia Carboniferous Arc and, 2) Early Permian A-type and peralkaline granites that represent a post-orogenic phase of voluminous granite emplacement. Both groups are significantly younger than the nearby Oyu Tolgoi and Tsagaan Suvarga Cu-porphyry ore bodies, which have previously been dated as early- and late-Devonian respectively. The new data presented here provide constraints on the timing of the transition from island-arc magmatism to post-collisional extension-related magmatism in the region and possible controls on fertile and infertile granitoid intrusions with respect to Cu–Au mineralisation.

This paper examines communicating geoscience to indigenous peoples using a communication model that closely follows geological models for pollution issues. Although geoscientists will expend large amounts of energy in understanding a scientific process, relatively little energy is often expended in the analogous communication model. Reasons for this include a narrow focus on pure science, lack of confidence in engaging in communication and negative perceptions of communication ideas. Indigenous peoples are defined as ‘first occupiers’ of regions or nations relatively untouched by the predominant ‘Western–Asian’ technological-oriented culture. Few indigenous peoples are totally ‘untouched’ by the dominant world culture. Four cases studies from the Solomon Islands explore communication strategies relating to land access, a live volcanic event, the setting up of a gold mine, and raising awareness of volcanic hazards. Generic best practice advice offered includes the following: understanding of indigenous culture, customs, values, taboos and political–governance structures; involvement of indigenous people at every level of the communication process; identifying and including all stakeholders; a clear message, method and outcome focus; usage wherever possible of face-to-face communication and pictures as well as words; involvement of the community in practical exercises; a thorough follow-up and evaluation process; and sufficient time to allow the process to be effective.

This paper reviews the principles and applications of sustainable development as applied to minerals (sustainable minerals). The key pillars of sustainable minerals are well known and include economic, community, environmental, and political considerations. The ideal solution is one that finds a balance between community benefit, economic development, profit, and minimal negative environmental and political impacts. This is, of course, fine in theory but in the ‘real world’ difficult to achieve. From a geoscience perspective this paper argues that non-private sector geoscientists have a crucial role to play in developing the sustainable minerals paradigm to an intellectually mature and usable form. The geoscience approach includes re-interpreting the rich legacy of geoscience data and acquisition of new data (geological mapping, 3 and 4D modelling, geophysical and geo­chemical information) and contextualizing this information with socio-economic and environmental data (e.g. ethnicity, social mix, wealth indicators, environmental sensitivity indicators) to assist with strategic and localized decision-making, maximizing benefits, and minimizing adverse impacts. This approach also involves modelling the full lifecycle of minerals, mines, mineral commodities, and mineral-bearing land in an attempt to quantify benefits and disbenefits of mineral extraction. One crucial key element of a sustainable minerals approach is a mix between ‘hard’ science and social science and genuine inclusion and consultation with stakeholders, especially impacted communities. As geoscientists we are in a position to explain clearly the benefits of mineral development to society and the disbenefits of ‘nimbyism’ (e.g. exporting problems to countries less able to manage mineral extraction) and promote a ‘custodianship’ ethos of mineral development that is the only way to realizing the key principle of sustainability, i.e. leaving the planet in a state that our grandchildren can enjoy.

The Saykhandulaan Inlier in South East Mongolia lies within the Central Asian Orogenic Belt (CAOB), and records a complex history of Palaeozoic tectonism and magmatism associated with terrane accretion on the northern margin of the Palaeo-Asian ocean. The inlier spans the boundary between the Gobi Altai back-arc basin terrane in the north and the Mandalovoo and Gurvansayhan island-arc terranes in the south which are notable for their many mineralised intrusions, including the Oyu Tolgoi gold-rich copper porphyry deposit. Results from cross-strike transects within the Saykhandulaan Inlier reveal that it can be subdivided into five parallel east–west striking litho-tectonic domains; (1) the Northern Slate Belt, comprising Devonian greenschist grade pelites and psammites with deep-marine to coastal siliciclastic protoliths; (2) the Saykhandulaan Valley Lineament Zone (SVLZ), a tectonised zone of faulted and lithologically altered volcanic rocks; (3) the High Strain Belt, consisting of tightly folded and flattened metamorphosed clastic sedimentary rocks; (4) the Molasse Succession, consisting of relatively undeformed coarse conglomerates and sandstones and, (5) the Oyut Ulaan Volcanic Group, a nearly 5 km-thick folded Carboniferous volcanic succession that hosts the mid-Carboniferous Oyut Ulaan mineralised granite. The Northern Slate Belt metasedimentary rocks record a northerly cratonic provenance, whereas all rocks to the south of the SVLZ have arc affinities. The SVLZ is thus interpreted to be the boundary between the Gobi Altai and Mandalovoo terranes. Two major deformation events are documented; (1) back-arc basin closure and inversion involving regional scale folding and greenschist grade metamorphism in the Northern Slate and High Strain Belts; (2) contraction associated with Mandalovoo terrane accretion and final closure of the Palaeo-Asian Ocean to the south. Following terrane accretion and cessation of subduction, crustal extension and strike-slip faulting fur

The composition of mining waste varies according to the nature of the mining operation and many other factors, but where the same mineral is extracted from a similar style of metalliferous or industrial mineral deposit or coal, the waste usually has similar characteristics. There are many potential sources of industrial minerals from mining waste. Waste from one mine may be a byproduct or coproduct in a mining operation elsewhere. Much technical research work on mine waste utilization, for example studies on slate waste, has included a manufacturing process. The waste is invariably an inferior material compared with an industrial mineral from a primary resource for the manufacturing process. Successful markets have not been found. Four scenarios are proposed where an industrial mineral product made from mining waste may be marketed successfully. These are a bulk product for a local market made with minimal or no processing; a low unit value product and a cost-effective alternative source of a mineral for local industry; an industrial mineral commodity traded nationally or internationally; and extraction of a high unit value rare mineral. Making an industrial mineral product from mining waste and successfully marketing it should involve minimal processing of the waste consistent with the value of the mineral product.

The Pacific small island state of Solomon Islands gained independence from Britain in 1978. Solomon Islands has a population of around 400 000 mainly Melanesian people distributed across six moderately sized islands and hundreds of smaller islands. The traditional economy has been based on hunter-gatherer and small-scale farming activities, with the bulk of the population residing in self-sufficient rainforest and coastal villages. Melanesians have a particularly strong cultural attachment to land, which is considered to be within the custodianship of the community at large. Individual land ownership in the Western economic sense is largely unknown. Melanesian society and culture is strong and complex. Colonial and post-independence Solomon Islands has had to face the challenges of a transition from a traditional society to a partially urbanized society and a rapidly increasing population and changing economic drivers and dynamics. Mining and mineral development is one area of economic activity that holds the promise of generating hard currency quickly to develop the country, but that needs to be achieved in a sustainable manner. Gold Ridge is situated in Central Guadalcanal, some 22 km southeast of the country’s capital town, Honiara. Gold Ridge hosts around 1.4 million ounces of epithermal volcanic-hosted gold. Ross Mining NL began the construction of Solomon Islands’ first gold mine in 1997 and operated a highly successful gold mine between 1997 and 2000, when ethnic tensions (unrelated to the mine) closed the operations. This paper documents the painstaking negotiations and planning that took place from 1993 and particularly from 1995 – 1996 which paved the way forward for the development of a gold mine within a fragile tropical rainforest environment among traditional Melanesian people who had little prior knowledge of modern mining activities.

At 07:45 a.m. on 2 April 2007, a tsunami hit Ghizo Island, western Solomon Islands in the south-west Pacific. Thirty-three people died on Ghizo, of whom 31 originated from a relatively small migrant Gilbertese community (transmigrated in the 1950s–1970s from Kiribati), while only two were from the majority Melanesian community. This paper documents an extensive 4-year study that addresses the potential core reasons for this asymmetrical casual impact. Community-participatory social science research was undertaken in two Gilbertese villages and two Melanesian villages. The four villages had similar spatial vulnerabilities due to their coastal location, although they had variable access to the safer higher ground. Gilbertese villages had less diverse ocean-reliant livelihoods, a limited knowledge of hinterland bush resource utilisation, uncertainties regarding land rights, and perceived ethnic discrimination. Melanesian villages had strong wantok and kastom social reciprocity cultures, a diverse set of livelihoods, wider social capital with other Melanesian communities, and greater security regarding land rights. This paper argues that these key factors—linked to the lower status as a migrant community of the Gilbertese, a limited sharing of knowledge between communities, government blind spots and power hierarchies—explain both the disproportionate impacts of the disaster and issues that impact longer-term aid intervention and social cohesion.

At 07:45 a.m. on 2 April 2007, a tsunami hit Ghizo Island, western Solomon Islands in the south-west Pacific. Thirty-three people died on Ghizo, of whom 31 originated from a relatively small migrant Gilbertese community (transmigrated in the 1950s–1970s from Kiribati), while only two were from the majority Melanesian community. This paper documents an extensive 4-year study that addresses the potential core reasons for this asymmetrical casual impact. Community-participatory social science research was undertaken in two Gilbertese villages and two Melanesian villages. The four villages had similar spatial vulnerabilities due to their coastal location, although they had variable access to the safer higher ground. Gilbertese villages had less diverse ocean-reliant livelihoods, a limited knowledge of hinterland bush resource utilisation, uncertainties regarding land rights, and perceived ethnic discrimination. Melanesian villages had strong wantok and kastom social reciprocity cultures, a diverse set of livelihoods, wider social capital with other Melanesian communities, and greater security regarding land rights. This paper argues that these key factors—linked to the lower status as a migrant community of the Gilbertese, a limited sharing of knowledge between communities, government blind spots and power hierarchies—explain both the disproportionate impacts of the disaster and issues that impact longer-term aid intervention and social cohesion.