NESE

Setting the scene

Mineralogy Petrology Geochemistry Volcanology

Rock Physics Geomaterials Magnetism

Cryosphere Planetary Solar System Science

Energy Resources Environment

Instruments development

Cryosphere, Planetary and Solar System Science
Answering geophysical questions concerning gas hydrates using neutron scattering. Gas hydrates, in particular methane hydrates, have received an ever increasing interest in geophysics over the last three decades due to their possible role as future energy resource, their role in the global climate change and their potential geo-hazards. Some gas hydrates also appear to play important roles in planetary bodies. Neutron scattering has proven to be a very powerful means of unravelling certain aspects of these materials.	• Neutron diffraction has provided the most accurate information on the compressibilities of gas hydrates and the gas content was determined for the first time on an absolute scale as a function of the p-T conditions. • Insight into physical properties has been gained from inelastic neutron scattering. • Formation and decomposition of gas hydrates has been followed by time-resolved in-situ neutron diffraction experiments. What can neutronsdo for geophysicists? answer questions and create new ones. What would be useful: A 2-D detector for kinetic work (crystal size, topotactic relations) Instruments for working with undeuterated H-rich materials. Neutron Instruments D20 at ILL - High-intensity two-axis diffractometer with variable resolution.	Presentation (PDF, 3.4MB)	Werner Kuhs Universität Göttingen GZG, Abt. Kristallographie Goldschmidtstr. 1 37077 Göttingen Germany wkuhs1@gwdg.de
Investigating planetary ices with neutrons The large icy moons of our Solar System are, as the name indicates, dominated by water ice, and water bonded with other species, such as ammonia, and possibly salts such as magnesium sulfate. • Water ice polymorphs: the equations of state of important phases, (specifically ice II & VI), are poorly characterised. • The phase diagram of ammonia dihydrate is not well known at all. • Magnesium sulfate hydrates are even more poorly understood.	Neutron diffraction in range of sample environments has allowed us to study the polymorphism of planetary ices and hydrates and measure their thermoelastic properties. These data help us constrain planetary models and interpret results from multi-billion dollar spacecraft such as Cassini-Huygens. Neutron Instruments HRPD ISIS - the High Resolution Powder Diffractometer, PEARL ISIS - High Pressure Facility - Paris-Edinburgh pressure cell, and OSIRIS a long wavelength diffractometer and backscattering crystal-analyser spectrometer located at the ISIS facility.	Presentation (PDF 4MB)	Andrew Dominic Fortes University College London Room OG.1 (Regional Planetary Image Facility) Kathleen Lonsdale Building, UCL. London Tel: +44 (0) 20 7679 2383 a.fortes@ucl.ac.uk
Phase transitions and kinetics of metastable amorphous ice modifications. Frozen water is a basic component of matter in the Solar system: Earth, Marth and planets’ satellites. The thermodynamic conditions, i.e., pressure and temperature, to which water is subject at thesatellites vary appreciably allowing, in accordance with water’s phase diagram, the formation of a variety of crystalline phases of different densities.	Neutron and x–ray scattering techniques show that in the case of the amorphous solid water modifications a classification of the sample state by the thermodynamic parameters pressure and temperature and the sample properties in its stationary state is not sufficient. Neutron Instruments IN6 at ILL spectrometer - cold neutron time-focussing time-of-flight spectrometer. D20 at ILL - High-intensity two-axis diffractometer with variable resolution.	Presentation (PDF 500KB)	Michael Koza ILL koza@ill.fr