August 7th – September 14th 2004, Tromsø – Tromsø (Norway)
The Arctic Coring Expedition was the first IODP Mission Specific Platform operation. Target area was the Lomonosov Ridge. The Lomonosov Ridge is named after Mikhail Lomonosov, an outstanding 18th century Russian scientist and lies about 1000 m below the sea-surface. This underwater mountain chain is 50 to 70 kilometres wide and stretches 1500 kilometres across the Arctic Ocean - from Greenland to Siberia. The Lomonosov Ridge is a splinter of continental crust separated from the siberian margin by the Gakkel spreading centre ca. 55 Mio years ago. Northward movement, combined with tilting and thermal subsidence influenced the crustal segment until reaching the recent position in the central Arctic Ocean. Since than around 500m sediment draped the ridge, recording the paleoceanographic and climate history of the Arctic realm.
1. Investigate the past 50 million years of Arctic environmental evolution from a "hothouse" to the present-day "icehouse".
2. Examine the detailed connections between climate development in the Arctic and in the North Atlantic over the past 25 million years.
3. Investigate the composition and origin of rock layers that are buried below the sediment cover of the Lomonosov Ridge to determine its origin.
4. Study the separation of the Lomonosov Ridge from the Eurasian continent and its subsequent drift to its present location.
Expedition 302 Proceedings