I is characterized by poorly-sorted facies with dispersed clasts. Two distinct facies are identified. I is predominant and is composed of silty clay serpentine with dispersed clasts and clast-poor serpentine diamicton. Facies II is present in two short intervals in Hole 1200E and is characterized by clast-rich serpentine diamicton. With the exception of increased clast content, these rocks are identical to Facies I, however no calcareous intervals occur within recovered intervals of clast-rich diamicton.
Core variability is evident in color reflectance data.
All cores were dark blue gray to black when first split, but became lighter in color once exposed to the aerobic environment of the core lab. Calcareous intervals oxidized rapidly after cores were split, revealing hues of light yellowish brown, light bluish gray, and light pink. Recorded calcareous intervals, and the location of clasts coated with a calcareous precipitate and calcareous nodules correlate well with microfossil content and abundance. Although most of the mud consisted of serpentine minerals, examination of the grit fraction revealed a rich population of high-pressure, low temperature rocks and minerals from the decollement, including glaucophane, white mica, crossite, amphibole, and chlorite schists. Benthic foraminifers in small quantity and low diversity are also present in all holes.