Suiyo has a prominent summit caldera, 1.5 km (0.9 mi) wide and 500 m (1,640 ft) deep.

Suiyo is covered by a thick sediment cap, a feature that collects over a long span of inactivity, and fault patterns and valleys have been observed on its flanks.

[2] Suiyo Seamount is associated with a magnetic anomaly: ocean-floor surveys of it and the surrounding area found that a large negative rock body existed to the east of the seamount, while positive bodies existed to the northwest and south.

The reasons for this complex anomaly, which also exists in several other nearby seamounts, are unknown, but is suggested to be the result of interactions between different magnetic fields of different ages.

[1] A bathymetric survey of the volcano found sulfur-oxidizing microbes to be predominant, and concluded that Suiyo Seamount was a natural "incubator" for this bacterial type.