Madeira Abyssal Plain

S0rensen, J., Jorgensen, K. S., CoUey, S., Hydes, D., Thomson, J., and Wilson, T. (1984). Depth localization of denitrification in a deep-sea sediment from the Madeira Abyssal Plain. Limnol. Oceanogr. 32, 758—762. 

Hoefs M. J. L., Rijpstra W. I. C., and Damste J. S. S. (2002) The influence of toxic degradation on the sedimentary biomarker record I. Evidence from Madeira Abyssal plain turbidites. Geochim. Cosmochim. Acta 66, 18. 

Prahl F. G., Eange G. J. D., Scholten S., and Cowie G. L. (1997) A case of post-depositional aerobic degradation of terrestrial organic matter in trubidite deposits from the Madeira Abyssal plain. Org. Geochem. 27(3/4), 141-152. 

The most direct field evidence that the extent of sedimentary organic matter preservation is affected by exposure to bottom-water oxygen comes from oxidation fronts in deepsea turbidites of various ages and depositional settings (Wilson et al., 1985 Weaver and Rothwell, 1987). One of these deposits in which the timing of the exposure to oxic and anoxic conditions is well documented, is the relict f-turbidite from the Madeira abyssal plain (MAP) —700 km offshore... 

De Lange G. J., Jarvis L, and Kuijpers A. (1987) Geochemical characteristics and provenance of late quaternary sediments from the Madeira abyssal plains N. Atlantic. In Geology and Geochemistry of Abyssal Plains (eds. P. P. E. Weaver and J. Thomson). Blackwell, London, pp. 147-165. 

Profiles of the weight percent organic carbon (%OC) and pollen abundances down two sequences of the f-turbidite from the Madeira Abyssal Plain. Oxidized sediments are those that have been exposed to oxygen after thousands of years of burial. See text for significance of these results. From Cowie et al. (1995). 

Some examples for the second case were provided by Schultheiss and McPhail (1986). By using an analytical instrument that freely sinks to the ocean floor, they were able to measure pressure differences between pore water, located 4 m below the sediment surface, and the bottom water directly. At some locations, deep sea sediments of the Madeira Abyssal Plain displayed pressure differences of about 0 Pa, at other locations, however, the pressure in pore water 4 m below the sediment surface was significantly lower (120 or 450 Pa) than in bottom water. With regard to the porosity (([)) and the permeability coefficient of the sediment (k), the advective flux is calculated according to the following equation ... 

De Lange, G.J., 1992b. Distribution of exchangeable, fixed, organic and total nitrogen in interhedded turbiditic/pelagic sediments of the Madeira Abyssal Plain, eastern North Atlantic. Marine Geology, 109 95-114. 

Abstract—The Canary basin consists of the continental margin off the coast of Northwest Africa, the deep basin, the Madeira Abyssal Plain (MAP) and the volcanic Canary Islands. 

The Canary Basin contains a varied geological setting along the continental shelf and slope off the Northwest African coast, the Canary Islands, and the Madeira Abyssal Plain (MAP) (Fig. 1). The MAP is situated in the deepest part (about 5400 m) of the Canary Basin about 700 km west of the Canary Islands (Jarvis and Higgs, 1987). 

Masson D. G. (1994) Late Quaternary turbidity current pathways to the Madeira Abyssal Plain and some constraints on turbidity current mechanisms. Basin Res. 6, 17-33. 

Morris R. J. (1987) Turbidite flows as a source of organic matter in deep water marine deposits evidence fixrm Quaternary sediments on the Madeira Abyssal Plain. Mem. Soc. Geol. Fr. 151, 43-53. 

Weaver P. P. E. and Kuhpers A. (1983) Climatic control of turbidite deposition on the Madeira Abyssal Plain. Nature... 

Madeira Abyssal Plain Fine-grained turbidites 6x10-5 Schuttenhelm et al. (1985)... 

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