First Field Tests of a New Multi-channel MRS Measuring Concept

The non-penetrative Magnetic Resonance Sounding (MRS) method allows a direct measurement of the absolute contend of mobile water in the subsurface. In addition, the average wide of the water-saturated pores can be estimated. The basic physical effect, which is used for this measurement, is the magnetic moment of the protons of hydrogen atoms of the water molecule. Unfortunately the standard MRS measurement concept which is based on a coincident loop configuration is relative slow and high sensitive against external natural and artificial magnetic noise. Moreover, measurements along profiles with 1-channel instruments are unacceptable time-consuming and will be applied only in exceptional cases. To reduce these problems we propose the use of a new type of 2-D loop layout in combination with an also new type of noise cancellation technique. In order to apply this new MRS measuring concept our MRS-MIDI II instrument, which is already optimized for shallow investigations, was upgraded to a 7-channel instrument (www.radic-research.de). First successful field data confirm the applicability of these concept.