The HPT-Triax is used to examine the physical properties of rocks.

High Pressure High Temperature Triaxial Cell

CSIRO has recently acquired a new high pressure and high temperature triaxial cell to better understand the physical properties of rocks.

• 12 May 2011 | Updated 14 October 2011

Overview

• Experimental data

CSIRO Earth Science and Resource Engineering has recently acquired a new high pressure and temperature triaxial cell, HPT-Triax (figure 1), manufactured by Sanchez Technologies. 

Data produced by the HPT-Triax allows us to better understand the physical properties of rocks under well-constrained laboratory conditions.

This rig can simulate natural in situ conditions and examine the changes in rocks associated with anthropogenic activity.

The physical properties of rock specimens and their evolution can be monitored as they are subjected to in situ stresses, pore fluids and temperatures. These rock properties are critical for:

• long-term predictions of geological storage of carbon dioxide/radioactive wastes
• exploration, production and monitoring workflows in conventional and unconventional (geothermal, tight gas or shale gas) geological environments.

Figure 1. High Pressure-High Temperature (HP-HT) triaxial cell. Independently controlled testing parameters: Confining pressure up to 150 MPa, Pore pressure up to 100 MPa, Axial stress up to 650 MPa, Temperature up to 200°C. Includes: 20 co-axial channels for active ultrasonic and passive micro-seismic monitoring and 12 channels for strain monitoring (Adapted from Sarout et al., 2010). Click to view higher resolution version.

Experimental data

Quantitative information about a rock specimen's physical state can be gained at any time during the experiment. Such experimental data are directly used for many field applications to assess:

• stress sensitivity of the seismic properties of rocks, for a better interpretation of 2D/3D/4D seismic field data
• seismic anisotropy for a better interpretation of 2D/3D cross-well data, vertical seismic profiling (VSP), amplitude versus offset (AVO), ray tracing or seismic tomography
• rock mechanical strength for borehole stability applications
• rock poroelastic properties for prediction of reservoir subsidence
• microseismic activity for application to reservoir subsidence monitoring, mining or hydraulic fracturing, (e.g. for enhanced oil recovery)
• fluid flow in reservoirs and sealing capacity of cap rocks.