caa a22 4500 467934150 CHVBK 20180406152952.0 cr unu---uuuuu 170328e20060501xx s 000 0 eng 10.1007/s10347-005-0037-x doi (NATIONALLICENCE)springer-10.1007/s10347-005-0037-x From sediment to rock: diagenetic processes of hardground formation in deep-water carbonate mounds of the NE Atlantic [Elektronische Daten] [Sibylle Noé, Jürgen Titschack, André Freiwald, Wolf-Christian Dullo] Modern cool-water carbonate mounds topped by corals form an extended reef belt along the NW European continental margin at 200-1200m water depth. An essential element of mound growth are hardgrounds which provide a stable substratum for mound-building invertebrate colonisation and stabilise the inclined mound flanks. Evaluating the degree of lithification and the slope stability against erosion represents an important task within the ESF programme MOUNDFORCE under the umbrella of EUROMARGINS. Sampling of hardgrounds during RV Meteor cruises M61-1 and -3 in 2004 by means of the IFM-GEOMAR TV-grab and the Bremen ROV QUEST focused on carbonate mounds of the Porcupine Seabight and northwestern Rockall Bank off Ireland. Lithified carbonates of mid-Pleistocene age were exhumed during the Holocene and are now exposed on the top and flanks of numerous carbonate mounds showing a patchy to dense colonisation by living corals and associated invertebrates. The sediments, composed of foraminiferal-nannoplankton oozes and admixed mound-derived invertebrate skeletons, range from partly lithified chalks to dense micritic limestones. These wackestones to packstones clearly differ from bacterially induced authigenic carbonate crusts typical of hydrocarbon seep settings by showing current-induced sedimentary structures, a non-luminescing matrix indicating oxic pore fluids, and a marine isotopic signature lacking any depleted carbon regime which is typical of anaerobic methane oxidation. The carbonate lithification is driven by carbonate ion diffusion from supersaturated seawater into the pore fluids in the studied areas. Vigorous bottom currents were the ultimate control not only of carbonate cementation by enhancing the diffusion process and supporting a pumping mechanism, but also of hardground formation and mound shaping by exhuming lithified carbonates and preventing fine-grained sediment accumulation at the downslope mound flanks. Springer-Verlag, 2005 Hardground formation nationallicence Carbonate diagenesis nationallicence Lithification nationallicence Carbonate mounds nationallicence NE Atlantic nationallicence Pleistocene-Holocene nationallicence Cold-water corals nationallicence Noé Sibylle Leibniz Institute of Marine Sciences, Wischhofstr. 1-3, 24148, Kiel, Germany aut Titschack Jürgen Institute of Paleontology, University of Erlangen-Nuremberg, Loewenichstr. 28, 91054, Erlangen, Germany aut Freiwald André Institute of Paleontology, University of Erlangen-Nuremberg, Loewenichstr. 28, 91054, Erlangen, Germany aut Dullo Wolf-Christian Leibniz Institute of Marine Sciences, Wischhofstr. 1-3, 24148, Kiel, Germany aut Facies Springer-Verlag 52/2(2006-05-01), 183-208 0172-9179 52:2<183 2006 52 10347 https://doi.org/10.1007/s10347-005-0037-x text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10347-005-0037-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Noé Sibylle Leibniz Institute of Marine Sciences, Wischhofstr. 1-3, 24148, Kiel, Germany aut NATIONALLICENCE 700 1- Titschack Jürgen Institute of Paleontology, University of Erlangen-Nuremberg, Loewenichstr. 28, 91054, Erlangen, Germany aut NATIONALLICENCE 700 1- Freiwald André Institute of Paleontology, University of Erlangen-Nuremberg, Loewenichstr. 28, 91054, Erlangen, Germany aut NATIONALLICENCE 700 1- Dullo Wolf-Christian Leibniz Institute of Marine Sciences, Wischhofstr. 1-3, 24148, Kiel, Germany aut NATIONALLICENCE 773 0- Facies Springer-Verlag 52/2(2006-05-01), 183-208 0172-9179 52:2<183 2006 52 10347 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer