Two seamounts on the northern part of Kyushu-Palau Ridge were explored by the Takuyo Expedition in August 1960. These seamounts stand abruptly about 1500m above a swell rising about 2000m gently from the Philippine Sea Basin with a NNW-SSE direction.
One of them, the Komahashi Seamount appears to have an uneven top which has its peak at the depth of 500m. The peak of the other seamount, the Takuyo guyot, is conical with a distinctly flat top 3.7 kilometers wide. There is a distinct break in the slope around the Takuyo guyot at the depth of about 700 meters. Apparently this seamount is a wave-truncated submerged volcano like the guyots on the Mid-Pacific-Mountains.