International Journal of Geophysics

Research Article

Frequency-Dependent Streaming Potential of Porous Media—Part 1: Experimental Approaches and Apparatus Design

Table 1

Specifications of an apparatus for making frequency-dependent streaming potential coefficient measurements.


Characteristic	Unit	Min.	Max.	Comment

Frequency	Hz	2	1000 (6500)	VTS-100 EM shaker (max. shaker spec. in parentheses)
Piston displacement	mm	0.1	22	VTS-100 EM shaker
Piston position precision	mm	±0.05		LVDT LD610-15 (Omega)
Dynamic pressure measurement	MPa (psi)	1.72 (250)		DPX101-250 dynamic pressure transducer (Omega)
		34.47 (5000)		DPX101-5K dynamic pressure transducer (Omega)
Pressure transducer proof pressure	MPa	34.5		DPX101-250 dynamic pressure transducer (Omega)
		103.4		DPX101-5K dynamic pressure transducer (Omega)
Pressure transducer noise floor	MPa	27.6 × 10⁻⁶		DPX101-250 dynamic pressure transducer (Omega)
		482.6 × 10⁻⁶		DPX101-5K dynamic pressure transducer (Omega)
Pressure transducer frequency range	Hz	0.08	1.7 × 10⁵	DPX101-250 dynamic pressure transducer (Omega)
		0.003	1.7 × 10⁵	DPX101-5K dynamic pressure transducer (Omega)
Pressure rise time	μs	1		DPX101-250 dynamic pressure transducer (Omega)
		1		DPX101-5K dynamic pressure transducer (Omega)
Pressure transducer resonant frequency	MHz	0.5		DPX101-250 dynamic pressure transducer (Omega)
		0.5		DPX101-5K dynamic pressure transducer (Omega)
Pressure transducer maximum frequency	MHz	0.17		DPX101-250 dynamic pressure transducer (Omega)
		0.17		DPX101-5K dynamic pressure transducer (Omega)
Pressure transducer preamp input impedance	Ω	10¹²		TL074IN J-FET input operational amplifiers
Electrode preamp input impedance	Ω	10¹²		TL074IN J-FET input operational amplifiers
Preamplification slew rate	V/μs	13		TL074IN J-FET input operational amplifiers
Maximum preamplification frequency	MHz	—	4.83	TL074IN J-FET, assuming maximum amplified signal is 10 V
Streaming potential measurement	mV		10⁴	Min. set by the noise floor. Max. limited by the preamp. circuits
Streaming potential constant	mV/MPa	0.029	5800	DPX101-250 dynamic pressure transducer (Omega)
		0.00145	290	DPX101-5K dynamic pressure transducer (Omega)
Sample length	cm	0.5	2	For rocks and clayey soils
		5	30	For sands and gravels and clay-free soils
Sample diameter	cm	1	1	For rocks and clayey soils
		2.54	2.54	For sands and gravels and clay-free soils
Temperature range	°C	−70	120	Defined by the pressure transducers