Zeta potential measured for an intact granite sample at temperatures to 200°C

Abstract

[1] Streaming potential was measured in an intact granite sample, saturated with aqueous KCl solutions at three different concentrations, at temperatures between 25°and 200°C. The magnitudes of the streaming potential coefficient and of the surface conductance (which dominates the sample conductivity) both increase with increasing temperature. Using a capillary model, we found that the magnitude of the zeta potential also increases with increasing temperature.INDEX TERMS: 5109 Physical Properties of Rocks: Magnetic and electrical properties; 5114 Permeability and porosity; 3947 Mineral Physics: Surfaces and interfaces; 8424 Volcanology: Hydrothermal systems (8135). Citation: Tosha, T., N. Matsushima, and T. Ishido, Zeta potential measured for an intact granite sample at temperatures

Changes in Electrokinetic Coupling Coefficients of Granite under Triaxial Deformation

“…The formation factor F of Inada granite under atmospheric pressure was estimated to be 1100 from the measurement of the resistance of the rock sample saturated with KCl solution with a high conductivity (0.2-1.1 S/m). Inserting these values into (6), we obtained the zeta potential as −11 mV, which is slightly smaller than the previously reported value of granite [17,18,29].…”

“…In the present study, we usedcoarse grained Inada granite (from a locality in Ibaraki, Japan), which has been often used as a standard specimen in rock mechanics (e.g., [27,29,34]). We used two specimens which were cored cylindrically 24 mm in diameter and 60 mm in length.…”

“…Electric potential was measured in the experiment using specimen G01 and electric current was measured in another experiment using specimen G02, respectively, because an electric potential and an electric current could not be measured at the same time. The sinusoidal oscillation method [29] enables us to measure the streaming potential (or current) induced by pore-fluid movement continuously during a rock deformation test. Figure 2 shows a typical data obtained by the oscillation test at a frequency of 0.01 Hz.…”

“…In laboratory experiments, zeta potential and streaming potential coefficients, fundamental quantities that characterize the electrokinetic effect, were measured for crushed rocks (e.g., [5,[17][18][19][20][21]) and for natural intact rocks (e.g., [22][23][24][25][26][27][28][29]) to determine the electrokinetic parameters as a function of pH, resistivity, permeability, or temperature. Jouniaux and Pozzi [23] measured the streaming potential coefficients of Fontainebleau sandstones under triaxial stress up to failure.…”

A review on electrokinetically induced seismo-electrics, electro-seismics, and seismo-magnetics for Earth sciences

“…The origin of this phenomenon was explained through the existence of an electric double layer acting as a condenser (von Helmholtz, 1879;Briggs, 1928). And anomalous behaviour of the zeta-potential in dilute solutions or in small capillaries had already been explained by the effect of surface conductance by McBain et al (1929); Urban and White (1932); Rutgers (1940), and White et al (1941).…”