Magnetic Resonance Testing (MR)

• MR uses a powerful electromagnet to transmit pulses that excite hydrogen magnetization and then measures the response
• The MR signal is generated and detected only within a thin cylindrical volume (shell) surrounding the center of the tool.
• The probe measures the initial amplitude and subsequent decay of the returning induced magnetic field
• The amplitude of the induced magnetic field directly indicates the quantity of hydrogen containing fluid in the formation. This is the volumetric water content in water bearing soils. In fully saturated soils, the volumetric water content also provides porosity and void ratio. In unsaturated soils, the gravimetric water content from a disturbed sample is required to determine void ratio

deployment

• Provides a direct measure of volumetric water content
• Empirical correlations for hydraulic transmissivity, mobile, and bound water
• Directly estimate porosity and void ratio in saturated soils
• Combine with disturbed sampling to estimate porosity, void ratio, and saturation in partially saturated soils