3. Toga and Iwabuchi: The middle and upper
parts of the slope show high magnetic anomaly. This
region is consistent with the unaltered Iwaine formation.
However, the lower slope of the landslide area
shows a significant low magnetic anomaly, because
the edge of the low-susceptibility Nirehara formation
and Funatsu granitic rocks has been hydrothermally
altered by the dyke and thick colluvium is distributed.