Adams Seamount

Geological summary

Adams Seamount was constructed above the Pitcairn hot spot in the central Pacific, about 90 km WSW of Pitcairn Island. The massive seamount rises about 3,500 m to within 59 m of the ocean surface about 25 km SE of Bounty Seamount. Bounty Seamount, which rises to within 450 m of the oceans surface, appears morphologically more youthful than Adams and water samples indicate continuing hydrothermal activity, two late-Pleistocene Potassium-Argon dates of about 338,000 and 350,000 years were obtained from the flanks. Alkali basaltic rocks were dredged from the flanks of Adams Seamount, whose summit appears to consist of a trachytic lava dome. Several Potassium-Argon dates of Holocene age were obtained from dredges at Adams Seamount (Guillou et al., 1997), the youngest of which was 2,000 +/- 1,000 years. In addition to the Adams and Bounty seamounts, the Pitcairn chain contains about 20 small volcanic cones about 500 m high.