Rock Mechanics Laboratory

The Rock mechanics Laboratory was established in the Earth Sciences Department in December 2010 and it is managed by Prof. Bob Holdsworth and Dr. Nicola De Paola.

Equipment

Low to High Velocity Rotary Shear Apparatus (LHVR): The LHVRS apparatus can measure the evolution of the frictional properties of both granular and solid rock materials at normal stresses up to 20 MPa and slip rates ranging from 1 mm/year to 1 m/s. By covering this range of velocities, the apparatus allows the laboratory investigation of poorly understood deformation processes occurring along active faults including both creeping movements and seismic slip.
Triaxial Loading Apparatus with Fluid Flow (TFF): The TFF apparatus allows the quantitative investigation of the fracturing processes of rocks during deformation under upper crustal pressure and temperature conditions (up to 10km depth), and how these processes can affect the evolution of the rock fluid transport properties. It also allows the quantitative estimation of the transport properties of rocks (both intact and granular) under evolving conditions of pore fluid pressure and in the presence of reactive fluids (i.e. carbon dioxide).
Biaxial loading frame: A high force biaxial frame has recenly been comissioned. This is fitted with two offset perspex sheets to allow simulations of fault stick-slip behaviour under a range of loading conditions, with analysis via high speed strain gauges and photography (see below).
ITASCA-Image “Milne” and “Richter” advanced Acoustic Emission system: This state-of-the art Acoustic Emission recorder (Applied Seismology Consultants) can measure 16 channels of AE data simultaneously, and locate the locations of the earthquakes in quasi-real time for display and analysis at data rate of up to 100 events/second. The instrument can also be used in a active mode, ‘pinging’ successive sensors to generate a dense P-wave raypath network for tomography. The recorder is used during triaxial deformation experiments to investigate the fracturing and cracking processes, due to applied stress and pore pressure.
High speed camera system: To investigate high speed stick-slip in the biaxial rig, a high speed camera may be slaved to the Acoustic Emission systems to track the formation and movement of stresses using high speed photo polarimetry.
High speed strainmeter system: Coupled with the above, a 12 channel high speed straimeter system is also available.

Current Projects

- Formation and evolution of basins, mountain belts and fault zones by integrating fieldwork and laboratory rock mechanics experiments with analysis of seismic reflection and remote sensing datasets;
- Development and application of novel techniques to acquire and analyse geospatial and rock mechanics data;
- Mapping rock friction and coupled fluid mechanics in active tectonic systems using high and low speed stick slip simulations on gypsum;
- Friction and stress transfer in seismogenic zones;