Experimental measurement and modelling of the steady-state and frequency-dependent electro-kinetic properties of rocks
- Start date: 1 September 2017
- End date: 30 September 2018
- Primary investigator: Professor Paul Glover
- Co-investigators: Dr Piroska Lorinczi
- External co-investigators: Professor Bangrang Di (China University of Petroleum, Beijing)
The petrophysics laboratory at the University of Leeds is perhaps unique in being able to offer a very wide range of instrumentation for the measurement of streaming potential of porous media.
We have the ability to measure the steady-state streaming potential coefficient of rock cores to a very high accuracy using our newly developed transient approach (see image to the right). In addition, we have developed capabilities for measuring the frequency-dependent streaming potential coefficient of both sands, bead packs, soils and loose aggregates, as well as small whole cores.
This experimental capability has led to recent publications of importance. The transient methodology for measuring the steady-state streaming potential coefficient was published in 2014, and the technique was subsequently used to measure the streaming potential of a range of different rock types with an accuracy that had never before been attained, more than tripling the number of data available in the literature.
Frequency -dependent methodologies have seen us publish data for sands and glass bead packs, and we are preparing publications at present in which whole rock cores have been measured.
Research is not confined to experimentation.
We have developed analytical theory and numerical models for all of our measurements. The 2012 theory describing steady-state streaming potential coefficient was the first available, superseding previously used empirical models, and remains the only theoretical approach available today.
The frequency dependence of streaming potential coefficient can be modelled using a number of heuristic approaches based on bundles of capillary tubes as analogues to a porous medium, or using Pride’s theory. In addition, in collaboration with Chinese colleagues a new numerical model for frequency-dependent streaming potential has been developed, and will hopefully be published soon.
We have tested this on clastic rocks and shales and found it to work well.
Publications and outputs
PENG, R., GLOVER, P., DI, B., WEI, J., LORINCZI, P., DING, P., & LIU, Z., 2018. The Effect of Rock Permeability and Porosity on Seismoelectric Conversion. In 80th EAGE Conference and Exhibition 2018 Proceedings. Copenhagen, Denmark: EAGE. doi:10.3997/2214-4609.201801203
GLOVER, P.W.J., 2018. Modelling pH-Dependent and Microstructure-Dependent Streaming Potential Coefficient and Zeta Potential of Porous Sandstones. Transport in Porous Media, 124(1), pp. 31-56.
GLOVER, P.W.J., RUEL, J., TARDIF, E. and WALKER, E., 2012. Frequency-dependent streaming potential of porous media - Part 1: Experimental approaches and apparatus design. International Journal of Geophysics, 2012.
GLOVER, P.W.J., WALKER, E. and JACKSON, M.D., 2012. Streaming-potential coefficient of reservoir rock: A theoretical model. Geophysics, 77(2), pp. D17-D43.
GLOVER, P.W.J., WALKER, E., RUEL, J. and TARDIF, E., 2012. Frequency-dependent streaming potential of porous media - Part 2: Experimental measurement of unconsolidated materials. International Journal of Geophysics, 2012.
WALKER, E. and GLOVER, P.W.J., 2018. Measurements of the Relationship Between Microstructure, pH, and the Streaming and Zeta Potentials of Sandstones. Transport in Porous Media, 121(1), pp. 183-206.
WALKER, E., GLOVER, P.W.J. and RUEL, J., 2014. A transient method for measuring the DC streaming potential coefficient of porous and fractured rocks. Journal of Geophysical Research: Solid Earth, 119(2), pp. 957-970.