Associate Editor of Preview Environmental Geophysics, Michael Hatch writes:
In this column Dave Walsh, president of US-based Vista Clara Inc., introduces some new geophysical tools that Vista Clara (VC) have developed to measure water content in the very near surface. VC has been producing state-of-the-art geophysical tools that use nuclear magnetic resonance to detect water in the subsurface. The instruments that he is introducing here are unique in their ability to characterize the shallow unsaturated zone both for water content as well as for relative pore size, with minimal to no physical disturbance of the soils in the zone of investigation. This work was done in collaboration with Ken Hurst Williams from Lawrence Berkeley Laboratory (US DOE); their interest was to develop tools for monitoring carbon cycling in near surface soils.