The Ice-breaker R.V. ARAON Expedition: Unveiling hidden history of the western Arctic Ocean

Abstract

Research expeditions to the western Arctic Ocean have been carried out by the Korean Icebreaker 「ARAON」in 2010 and 2011. The main goal of this marine geological research is to reconstruct glacial history and palaeoceanographic changes (sea-ice coverage, brine formation, palaeoproductivity, origin of organic matters) in the western Arctic Ocean during the late Quaternary glacial-interglacial cycles. One focus was to gather sedimentary materials and therefore establish chronostratigraphy of the sediments across the Chukchi shelf and the southern Mendeleev Ridge. The shipboard echosounder systems (Multi-beam Bathymetry and Sub-bottom Profiling) were continuously operated during the entire expedition to decide suitable coring sites based on a high-resolution seismic profiles for the uppermost sediment sections. Box, multiple and gravity cores were retrieved with the ARAON coring system. Directly after retrieval, the cores were divided into 150cm sections and brought to the sedimentology lab onboard for core curation (e.g. photography, description, photospectrometry, subsampling). Here we present preliminary results obtained from multi-proxy analyses of onshore laboratory as well as the onboard analyses conducted on the sediment core samples retrieved during the ARAON expeditions. (sea-ice coverage, brine formation, palaeoproductivity, origin of organic matters) in the western Arctic Ocean during the late Quaternary glacial-interglacial cycles. One focus was to gather sedimentary materials and therefore establish chronostratigraphy of the sediments across the Chukchi shelf and the southern Mendeleev Ridge. The shipboard echosounder systems (Multi-beam Bathymetry and Sub-bottom Profiling) were continuously operated during the entire expedition to decide suitable coring sites based on a high-resolution seismic profiles for the uppermost sediment sections. Box, multiple and gravity cores were retrieved with the ARAON coring system.