Initial Reports of the Deep Sea Drilling Project, 12

Abstract

Representative photographs of cores collected from the Mississippi Fan and Orca and Pigmy basins during DSDP Leg 96. Fining-upward channel sequences recovered in midfan channel Sites 621 and 622 contain (A) a basal gravel channel lag (621-33,CC), overlain by (B) sands (621-33-2, 105-123 cm), overlain by (C) a passive clay and mud channel fill (621-10-2, 115-133 cm). The sequence drilled at Site 615 on the lower fan includes (D) a carbonate debris flow (615-50-4, 115-133 cm), overlain by (E) thin, cross-stratified silts (615-12-2, 85-103 cm) and interbedded (F) silt and clay laminae (615-11-3, 105-123 cm). Sediments recovered at fan margin Site 616 document an upper mass movement deposit, 100 m thick and typified by (G) high-angle slump material (616-6-6, 20-38 cm). Sediments recovered from intraslope basin Sites 618 and 619 consist of (H) pelagic and hemipelagic clay laminae (619-11-3, 100-118 cm).

Calcareous Nannofossils from Cores Recovered during Leg 18, Deep Sea Drilling Project: Biostratigraphy and Observations of Diagenesis

“…The low diversity of this assemblage and the near absence of discoasters is a function of a cold (middleto high-latitude) environment of deposition. Discoaster deflandrei is a cosmopolitan species which, in the North Atlantic, occurs in sediment as high as 59°56'N where waters are warmed by the Gulf Stream (Leg 12, Site 114; see Laughton et al, 1972). Most other species of discoaster, however, are found at low or middle latitudes and, as a rule, Discoaster is considered to be a warm-water genus.…”

The Western Rockall Plateau: Stratigraphy and Structural Evolution

“…These preliminary data provided the regional background for Sites 116 and 117 drilled by D/V Glomar Challenger during Leg 12 (Laughton, Berggren, et al, 1972). Subsequent seismic and magnetic surveys carried out by IOS, Lamont-Doherty Geological Observatory (L-DGO), and the U.S.…”

Introduction

“…The absolute ages of the major boundaries shown in Table 2 are from Laughton, Berggren et al (1972). The uncertainty of any of the values shown is probably less than 4 my, based on the various compilations published during the past four years.…”