Petrology of ultramafic rocks at DSDP Holes 82-556, 82-558, and 82-560@en

Strongly serpentinized peridotites occur at shallow crustal levels at DSDP Sites 556 (35-Ma-old crust), 558 (35-Maold crust), and 560 (12-Ma-old crust) in the North Atlantic. Primary peridotite silicate minerals are preserved only at Sites 556 and 558, but all three sites have primary spinel preserved. The serpentinites at all three sites were probably spinel harzburgite tectonites, with little or no clinopyroxene. […]