Department of Geology and Mineralogy, Oxford University, Oxford, OX1 3PR.
Deposition of fine-grained sediments in the abyssal environment of the Algéro-Balearic Basin, Western Mediterranean Sea
Article first published online: 14 JUN 2006
Volume 22, Issue 1, pages 95–109, February 1975
How to Cite
RUPKE, N. A. (1975), Deposition of fine-grained sediments in the abyssal environment of the Algéro-Balearic Basin, Western Mediterranean Sea. Sedimentology, 22: 95–109. doi: 10.1111/j.1365-3091.1975.tb00285.x
- Issue published online: 14 JUN 2006
- Article first published online: 14 JUN 2006
- Manuscript received 19 January 1974; revision received 4 July 1974
Two depositional processes control the mud accumulation on the southern Balearic Abyssal Plain: pelagic settling at a rate of 10 cm/1000 years, and turbidity currents at an average frequency of > 3 per 2000 years. Thermo-haline bottom flow has little effect on the abyssal sediment distribution. Just over half of the Late Quaternary section is made up of turbidite mud. Distinctive properties of turbidite mud are: structural, textural, and compositional continuity from the underlying turbidite sand-silt layer into the overlying mud, grading within the mud layer, a ratio of carbonate percent with the underlying turbidite sand-silt layer of about 0.5, and a proportion of sand of > 1%. Those of (hemi)pelagic mud are: bioturbation, an average of 8% of sand consisting largely of remains of foraminifera and pteropods, a grain size distribution which is virtually normal with a median around 9 φ, and very poor sorting; in general, the properties of (hemi)pelagic muds are the same in widely separated localities and depths in cores. In some instances the clay mineral ratios of the turbidite mud layer are markedly different from those of the overlying (hemi)pelagic mud layer.