Rock eval analysis of organic matter in sediment core 159-959D

The Cretaceous Equatorial Atlantic Gateway between the Central and South Atlantic basins is of interest not only for paleoceanographic and paleoclimatic studies, but also because it provided particularly favourable conditions for the accumulation and preservation of organic-rich sediments. Deposition of carbonaceous sediments along the Côte d'Ivoire-Ghana Transform Margin (Ocean Drilling Program Leg 159) was intimately linked to the plate tectonic and paleoceanographic evolution of this gateway. Notably, the formation of a marginal basement ridge on the southeastern border of the transform margin provided an efficient shelter of the landward Deep Ivorian Basin against erosive and potentially oxidizing currents. Different subsidence histories across the transform margin were responsible for the development of distinct depositional settings on the crest and on both sides of the basement ridge. Whereas the southern, oceanward flank of the basement ridge was characterized by rapid, continuous deepening since last Albian-early Cenomanian, marine sedimentation on the northern, landward flank was interrupted by a period of uplift and erosion in the late Albian, and rapid subsidence started after the early Coniacian. Organic-rich sediments occur throughout almost the entire Cretaceous section, but hydrogen-rich marine black shales were exclusively recovered from core sections above an uplift-related unconformity. These black shales formed when separation of Africa and South America was sufficient to allow permanent oceanic midwater exchange after the late Albian. Four periods of black shale accumulation are recovered, some of them are correlated with the global oceanic anoxic events: in the last Albian-earliest Cenomanian, at the Cenomanian-Turronian boundary, during the middle Coniacian-early Campanian, and in the mid-Maastrichtian. These periods were characterized by increasing carbon flux to the seafloor, induced by enhanced palaeoproductivity and intensified supply of terrestrial organic matter. Black shale depostion appears to be intimately linked to periods of rising or maximum eustatic sea level and to the expansion of the oxygen minimum zone, as indicated by foraminiferal biofacies. Intervals between black shales units, in contrast, indicate a shrinking oxygen minimum zone and enhanced detrital flux rates, probably related to lowering sea level. Upper Cretaceous detritral limestones with high porosities may provide excellent hydrocarbon reservoirs, alsthough their areal extent appears to be limited. Palaeogene porcellanites, capped by Neogene pelagic marls and clays, extend over a wider area and max provide another target for hydrocarbon exploration.

Analysis of Mn nodules from cruise GH72-2

The GH72-2 shipborne survey was carried out in the northwest Pacific during 31 days under the 'Basic investigations for exploration of deep sea mineral resources' program. The sediments encountered could be classified as follows: 1) Most of the brown clays occur on the abyssal plain of the basins at depth over 4500m. 2) Calcareous oozes are predominant at the top, slope and foot of seamounts and guyots. 3) Terrigeneous sediments are distributed near islands. The concentrated zone of ferromanganese nodules was located in the Magellan seamounts area. However, the metal contents in Mn, Cu, Ni and Co for these nodules are relatively poor, and these ferromanganese deposits occur at a depth over 5000m. It is interesting to note that the shape of the nodules is sometimes nearly spherical, and that the chemical composition of the nodules is characterized by the low ratio Mn/Fe and Co/Ni.

Final regulatory analysis of the model year 1982 light truck fuel economy standards.

Mode of access: Internet.

School feeding programs in developing countries : an analysis of actual and potential impact /

"PN-AAL-060"--Cover.

Analysis of subpoenaed television data /

March 1978.

A comparative analysis of results from three recent non-separated concurrent-flow high occupancy freeway lane projects : Boston, Santa Monica, and Miami.

"Service and methods demonstration program."

State program implementation guide : hazardous waste transportation control /

Mode of access: Internet.

An analysis of ultimate performance measures to determine total project impact.

National Highway Traffic Safety Administration, Washington, D.C.

An analysis of ultimate performance measures to determine total project impact. (A supplementary report to analytic studies no. 1 and no. 3 for project year 1973.).

National Highway Traffic Safety Administration, Washington, D.C.

An analysis of the mini ASAP rehabilitation countermeasures, 1975. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

An analysis of public information and education countermeasures: 1975, final report.

National Highway Traffic Safety Administration, Washington, D.C.

Rehabilitating drinking drivers: an analysis of three years of activities of the New Hampshire Alcohol Safety Action Project. Final report.

National Highway Traffic Safety Administration, Office of Driver and Pedestrian Programs, Washington, D.C.

An analysis of total project impact. Analytic study no. 1.

National Highway Traffic Safety Administration, Washington, D.C.

Analysis of drinker diagnosis and referral activity. Analytical study no. 5. 1973.

National Highway Traffic Safety Administration, Washington, D.C.

San Antonio Alcohol Safety Action Project. Analytic study no. 1-2. Analysis of overall project impact. Final report.

National Highway Safety Administration, Washington, D.C.