georefid:2009-026077SEDIS Publication Catalogueana.macario@awi.dehttp://sedis.iodp.org/pub-catalogue/informationpointOfContact2011-07-06T00:00:00Zhttp://sedis.iodp.org/pub-catalogue/index.php?id=2009-026077<gco:CharacterString>Sedimentary cover of the Lomonosov Ridge near the North Pole based on seismic data</gco:CharacterString>2008-01-01publicationgeorefid:2009-026077Lebedeva-Ivanova, NinaUppsala University, Uppsala, SwedenauthorArthun, ToreBergen University, NorwayauthorKristoffersen, Yngveauthor[International Geological Congress], [location varies], InternationalpublisherdocumentHardcopyIn: Anonymous, 33rd international geological congress; abstracts33Seismic data collected across the Lomonosov Ridge near the North Pole by the Russian drift ice-stations NP-28, the Alfred Wegener Institute (AWI) and expeditions by the Swedish icebreaker Oden show that the top of the Ridge is capped by a few hundred meters of low-velocity sediments, unconformably overlying higher velocity units. The NP-28 reflection profiles are characterized by a prominent composite reflection package directly above the discontinuity (referred as the Lomonosov Unconformity) emphasizing the importance of this stratigraphic break. The ACEX 2004 drilling on the Ridge on the AWI-91090 reflection profile, showed that the low-velocity sediments are Cenozoic. A hiatus (or several hiati) occur in the middle Miocene to the middle Eocene interval at c100-200 m bsl and is traceable on most of the seismic sections. The prominent composite reflection package above the Lomonosov Unconformity formed in the late Paleocene - early Eocene. Below the Unconformity, sedimentary rocks have a Mesozoic or even older age. The top of the acoustic basement on NP-28 sections is marked by strong reflections. Some less regular deeper reflections are traceable within this basement. New seismic reflection data were collected in the central part of the Lomonosov Ridge near the North Pole by the HOTRAX'05 expedition. This central part of the Ridge has a saddle point which includes an interior basin. Preliminary results of processing the data are presented, illustrating the structure of the sedimentary cover in the basin and on surrounding ridges.completedApplied geophysicsArctic Coring EXpeditionArctic OceanArctic regionCenozoicExpedition 302geophysical methodsIntegrated Ocean Drilling ProgramLomonosov Ridgelow-velocity zonesNorth Polereflection methodssedimentary coverseismic methodsTertiaryunconformitiesurn:org.iodp:exp:302urnlargerWorkCitationcampaignEnglishgeoscientificInformation-180.0000180.000070.000090.0000Arctic OceanNorth Pole