A new research programme on ‘Bedrock fracture by ice segregation’, funded by the Natural Environmental Research Council, has commenced in the cold laboratories at the CNRS Centre de Géomorphologie, Caen, France.
Four sets of experiments, each running for a year, will monitor the effects of different thermal regimes, moisture conditions and material properties on rock fracture, ice segregation and frost heave in large blocks of limestone and sandstone. Experimentally-formed fractures and segregated ice will be compared with predictions from two theoretical models of rock fracture and frost heave, and the observed rock fractures compared with contemporary and relict weathering profi les. The research is led by Julian Murton (University of Sussex) and Jean-Claude Ozouf (CRNS Caen), in collaboration with Jean-Pierre Coutard, Jean-Pierre Lautridou and Gerard Guillemet (CNRS Caen), David Robinson and Rendel Williams (Sussex) and Rorik Peterson (University of Alaska, Fairbanks).
The UK radioactive waste management company Nirex is involved in an international collaborative project, PERMA, to study the characteristics of a permafrost fi eld site that might be of relevance to safety assessments for northern European deep geological radioactive waste disposal. The investigations are being carried out at a gold mine in northern Canada together with partners from Finland (POSIVA and GTK), Sweden (SKB) and Canada (OPG and University of Waterloo). The partners are aiming to improve the understanding of the subsurface hydraulic and chemical processes and the behaviour of crystalline bedrock under permafrost conditions. Thermal and mechanical processes are also of interest. Activities carried out to date include electromagnetic SAMPO soundings in the vicinity of the mine, to provide information on the permafrost depth, fracture zone characteristics and possible talik structures, and surface and subsurface water sampling. The project continues into 2003.
Nirex have recently commissioned a report on ‘Middle and Late Quaternary Permafrost and Periglacial Environments in the UK: A Review of Geological Evidence, by Professor Charles Harris, Cardiff University: UK Nirex Ltd (code KSGE050), May 2002. This report is in the public domain. Development of scaled physical modelling of cryogenic processes was continued under the direction of Charles Harris, at the Cardiff University School of Engineering Geotechnical Centrifuge Centre. The research is funded by the UK Natural Environment Research Council and the Royal Society. Work in progress includes investigation of the signifi cance of soil properties and slope geometry on solifl uction processes and shallow periglacial landsliding with James Smith, Cardiff University, and an investigation of the signifi cance of host sediments (geotechnical properties and ice content) during the thawing of ice wedges and the formation of ice-wedge casts with Julian Murton, Sussex University. Experiments are performed at scales of between 1/10 and 1/30, under elevated gravity fi elds ranging from 10 gravities to 30 gravities. The technique allows full-scale, self-weight stresses to be replicated within the scaled model, so that pore pressures and soil stress/strain relationships can be accurately modelled. Centrifuge modelling is also in progress at the University of Dundee under the direction of Michael Davies, where the interaction between engineering structures and thawing soils, and the signifi cance of warming temperatures to the stability of frozen rock slopes are under investigation.
A two-day conference organised by the British Geomorphological Research Group and the Quaternary Research Association will be held on 13-14 January 2003 at the Geological Society, Burlington House, London London entitled Cryospheric Systems. The conference will focus on glacial and periglacial systems and in particular their interactions, in terms of processes, landforms and sediment associations, in the context of climate change. Conference convenors, Charles Harris, Julian Murton and David Evans.
Charles Harris (firstname.lastname@example.org)