A high-resolution P-wave seismic reflection profile was acquired across the toe of the Senya thrust, northern Honshu, Japan, to test the applicability of profiling using a hummer source (3.5 kg). Seismic data was recorded by a portable recording system (60 ch), with 28Hz geophones spaced at 0.5m intervals, and processed by standard Common Mid-Point (CMP) method. The obtained seismic section clearly demonstrates an eastdipping thrust down to 40-m in depth. The geometry of the thrust well fit to the subsurface structure estimated by drill core data.