Bucking the trend: part-time Master’s students at the University of Northampton

Nick Petford, Vice Chancellor of the University of Northampton, and Nick Allen, Executive Officer at the University of Northampton, explain how their institution has bucked the decline in part-time study for postgraduates and push the benefits of working with local industry partners on bespoke programmes

Rheology and Multiphase Flow in Congested Ammonia-Water-Ice Slurries

Cryomagmas are natural examples of complex multiphase fluids. Some preliminary statements are made about the rheology of densely packed suspensions that have important bearing on their flow rates and eruptive style. Abstract no.104

Addams Crater, Venus, Venus: outflow analogous with a submarine debris flow?

The extraordinary outflow length and morphology of Addams crater deposits are compared with the Saharan submarine debris flow off Northwest Africa. Vapor cloud modelling and comparison of sonar data with radar images suggest a possible similar origin for the Addams crater outflow deposits

Goalposts on the Move

The impact profile of recent UK geoscience research is set to change, say Nick Petford & Jonathan Adam

Deformation-Induced Mechanical Instabilities at the Core-Mantle Boundary

Post-Perovskite: The Last Mantle Phase Transition Our understanding of the core-mantle boundary (CMB) region has improved significantly over the past several years due, in part, to the discovery of the post-perovskite phase. Sesimic data suggest that the CMB region is highly heterogeneous, possibly reflecting chemical and physical interaction between outer core material and the lowermost mantle. In this contribution we present the results of a new mechanism of mass transfer across the CMB and comment on possible repercussions that include the initiation of deep, siderophile-enriched mantle plumes. We view the nature of core-mantle interaction, and the geodynamic and geochemical ramifications, as multiscale processes, both spatially and temporally. Three lengthscales are defined. On the microscale (1-50 km), we describe the effect of loading and subsequent shearing of the CMB region and show how this may drive local flow of outer core fluid upwards into D". We propose that larger scale processes operating on a mesoscale (50-300 km) and macroscale regimes (> 300 km) are linked to the microscale, and suggest ways in which these processes may impact on global mantle dynamics

Changing Sources of Magma Generation Beneath Intra-Oceanic Islands Arcs: An Insight From the Juvenile Kohistan Island Arc, Pakistan Himalaya

The Kohistan arc, situated in the Pakistan Himalaya, is a Cretaceous intraoceanic island arc which was initiated during the northward movement of the Indian Plate. The arc was sutured to Asia at ca. 100 Ma. It was subsequently tilted northward when underplated by Indian continental crust during the early stages of India–Asia collision. Deep erosion of this tilted section provides a spectacular section through the whole arc sequence and offers a profound insight into the mechanisms of early stages of arc formation. Geochemical analysis and rare earth element modelling of basaltic sequences which date from the intraoceanic stages of arc development allow identification of three main magma source types in the mantle beneath the juvenile arc. The ‘E-type’ Kamila Amphibolites, with a MORB-type chemistry, form the intraoceanic basement to the arc. The ‘D-type’ Kamila Amphibolites are the earliest of the arc volcanic rocks. These were extracted from a primitive spinel-bearing mantle source, above a north-dipping subduction zone. The stratigraphically younger basalts of the Jaglot Group and Ghizar Formation of the Chalt Volcanic Group were derived from partial melting of a garnet-bearing source at greater depth. The Hunza Formation of the Chalt Volcanic Group contains the youngest mafic volcanic rocks of the intraoceanic arc. Although coeval with the Ghizar Formation of the Chalt Volcanic Group, they were generated by melting of a depleted, spinel-bearing mantle source rock and were erupted into a spatially and temporally restricted back-arc basin developed behind the volcanic front. The Chalt Volcanic Group was therefore formed from two different, adjacent, mantle source regions active at the same time. Results of REE modelling are consistent with models for intraoceanic arc formation in which the earliest volcanic rocks are derived from shallow level spinel-bearing peridotite, and later ones from a deeper garnet-bearing source. This is consistent with the melt region becoming deeper with time as subduction continues. A two-stage model is proposed for the back-arc basalts of the Hunza Formation in which a mantle source, depleted from a previous melting event, is underplated beneath the arc and later remelted during decompression as a consequence of extension and rifting of the arc

Image based modelling of lateral magma flow: the Basement Sill, Antarctica

The McMurdo Dry Valleys magmatic system, Antarctica, provides a world-class example of pervasive lateral magma flow on a continental scale. The lowermost intrusion (Basement Sill) offers detailed sections through the now frozen particle microstructure of congested magma slurry. We simulated the flow regime in 2 and 3D using numerical models built on a finite element mesh derived from field data. The model captures the flow behaviour of the Basement Sill magma over a viscosity range of 1-104 Pa s where the higher end (≥102 Pa s) corresponds to a magmatic slurry with crystal fractions varying between c. 30 and 70%. A novel feature of the model is the discovery of transient, low viscosity (≤ 50 Pa s) high Reynolds number eddies formed along undulating contacts at the floor and roof of the intrusion. Numerical tracing of particle orbits implies crystals trapped in eddies segregate according to their mass density. Recovered shear strain rates (10 3 to 10-5 s-1) at viscosities equating to high particle concentrations (> c. 40%) in the Sill interior point to shear-thinning as an explanation for some types of magmatic layering there. Model transport rates for the Sill magmas imply a maximum emplacement time of c. 105 years, consistent with geochemical evidence for long range lateral flow. It is a theoretically possibility that fast-flowing magma on a continental scale will be susceptible to planetary-scale rotational forces

BURO: A Bespoke Repository for the UK Research Excellence Framework & Beyond

BURO (Bournemouth University Research Online), a bespoke repository for the university’s research publications is an essential part of a wider change agenda aimed at embedding research into the core activities of Bournemouth University. BURO will be a crucial piece of this jigsaw as the university prepares for the UK’s forthcoming Research Excellence Framework (REF) and beyond. BURO is the 11th largest multidisciplinary institutional repository in the UK and 232nd in the Web of World Repositorie

Numerical modelling of liquid metal transport in partially molten H5 ordinary chondrite

An equation-based model of liquid metal segregation in Fe-bearing chondrite meteorites is presented. Textural data from natural samples provide the input conditions. Initial results confirm porous flow of Fe-Ni-S liquid alloy as an important metal segregation mechanism in planetary interiors