Laminae type and possible mechanisms for the formation of laminated sediments in the Shaban Deep, northern Red Sea

I. A. Seeberg-Elverfeldt (1) , C. B. Lange (2) , J. Pätzold (1) , G. Kuhn (3)

1 Research Center Ocean Margins
2 Center for Oceanographic Research in the eastern South Pacific (FONDAP-COPAS)
3 AWI - Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung = Alfred Wegener Institute for Polar and Marine Research = Institut Alfred-Wegener pour la recherche polaire et marine

Laminated sediments in the Shaban Deep, a brine-filled basin in the northern Red Sea, were analyzed with backscattered electron imagery. Here we present possible mechanisms involved in the formation of laminae of various types and homogenous intervals arising from the detailed investigation of multicore GeoB 7805-1 (26°13.9' N and 35°22.6' E; water depth 1447 m) and gravity core GeoB 5836-2 (26°12.61' N, 35°21.56' E; water depth 1475 m). Sediment makeup includes six types: a) a laminated structure with alternating light (mainly coccoliths) and dark (diatom frustules) layers, where the diatom component is indicative of the intra-annual variability between stratification and mixing events; b) a pocket-like structure attributed to the sinking of particles within fecal pellets and aggregates; c) a matrix of tightly packed diatoms that relates to extended stratification/mixing periods of the water column; d) homogenous intervals that result from turbidity deposition; e) silt accumulations which origin may lie in agglutinated foraminifers; and f) pyrite layers with pyrite formation initiated at the seawater-brine interface.

Domaines: Océan, Atmosphère

I. A. Seeberg-Elverfeldt, C. B. Lange, J. Pätzold, G. Kuhn. Laminae type and possible mechanisms for the formation of laminated sediments in the Shaban Deep, northern Red Sea. Ocean Science, 2005, 1 (2), pp.113-126. ⟨hal-00298274⟩