Archive

Wed 27th April @ 12 pm, Rm 312.222 Thermal waters at Yellowstone National Park contain high concentrations of arsenic (up to 15 mg/L), lithium (up to 8 mg/L), boron (up to 28 mg/L), fluoride(up to 48 mg/L), and silica (up to 800 mg/L). Their geochemical source, redox transformations, and transport have been challenging to decipher. Arsenic speciation requires knowledge of thioarsenites and thioarsenates. We have measured the mass […]

Wed 23rd March @ 12 pm, Rm 312.222 Zircon (ZrSiO4) is renown for being physically robust, and is arguably the most significant accessory mineral because it continues to revolutionize our understanding of the evolution of Earth, Moon and other bodies. But is zircon forever? What happens to this tough little cookie under extreme conditions, where it can […]

Wed 16th March @ 12 pm, Rm 312.222 Micro-continental ribbons form anomalous buoyant crustal material stranded with oceanic crust.  Such ribbons can form in a variety of tectonic settings including incipient ocean crust formation and subduction roll back.  When micro-continental ribbons interact with convergent margins they have a profound effect on the dynamics of the margin and […]

Wed 2nd March @ 12 pm, Rm 312.222 Abstract There is probably no such thing as a “typical” passive margin, although the southern margin of Australia comes close.  On this margin an Upper Jurassic rift propagated through an ancient cratonic block, deep within a continent, culminating in the generation of oceanic crust and the eventual separation of […]

 Wed 18th November @ 12 pm, Rm 312.222 Eclogitic xenoliths from kimberlite are occasionally diamond-bearing, and are often interpreted as having an origin as subducted oceanic crust [1]. The existence of diamonds in these rocks constrains equilibrium temperatures and pressures of some eclogites to the upper mantle. However the additional critical parameter controlling the stability of diamonds, […]

Thurs 5th November @ 12 pm, Rm 302.001 (please note the venue)   New mapping techniques allow us to define with unpreceded detail seafloor morphology; scientific literature is flooded with a growing number of researches based on high-resolution bathymetry and/or morphometry depicting new geological features and processes. Such techniques however will give an important, up to essential, […]

Wed 4th November @ 12 pm, Rm 312.222 Global maps of crustal thickness on the Moon, derived from gravity measurements obtained by NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission, have shown that the lunar crust is thinner than previously thought. Hyperspectral data obtained by the Kaguya mission have also documented areas rich in olivine that have […]

 Wed 28th October @ 12 pm, Rm 312.222 Abstract The geotectonic history of the interior of East Antarctica is poorly known due to limited bedrock exposure and patchy geophysical imaging. Outcrop of the Nimrod Group in the adjacent central Transantarctic Mountains reveals a crustal history beginning by 3.1 Ga, with significant additions at ~2.5 and ~1.7 Ga, […]

Wed 21st October @ 12 pm, Rm 312.222 The treatment of metamorphism as a sequence of near-equilibrium reactions responding to progressive changes in temperature and pressure (T,P) forms the basis of our understanding of crustal evolution. In fluid-producing reactions during progressive burial of a sediment, there may be an argument to support this, since mineral reactions in […]

Wed 23rd September @ 12 pm, Rm 312.222 Abstract Pb isotope system is a powerful tool that played a significant role in emergence of current understanding of differentiation and evolution of the Earth. Since initial recognition that variability of Pb isotope compositions in many rocks can be linked to the existence of several planetary scale reservoirs, Pb […]