Burrow morphologies in north-central Pacific sediments

An examination of split core photographs from the north-central Pacific reveals the presence of three different burrow morphologies. Simple burrows occur throughout the region. Halo burrows are present in water deeper than 4,000 m (3,000 m along the equator) and removed from continental areas. Imbricate burrows are uncommon and have an irregular distribution. Organisms responsible for the burrows are interpreted as surface to near-surface feeders which do not penetrate deeply into the sediments. Thus, the zone of sediment mixing caused by burrowing ranges from 10 to 30 cm and averages 20 cm.