Deep-Sea Drilling in the Norwegian-Greenland Sea and Arctic Ocean a tribute to manik Talwani
|Location||International Geological Congress,oslo 2008|
|Author||Thiede, Joern۱; Eldholm, Olav۲; Myhre, Annik۳|
|Holding Date||09 September 2008|
Some 30 years ago marine geophysicists under the leadership of Manik Talwani from at that time Lamont-Doherty Geological Observatory of Columbia University succeeded to unravel the plate tectonic history of the Norwegian-Greenland Sea and of the eastern Arctic Ocean. The patterns of sea-floor spreading-type magnetic anomalies suggested that these ocean basins had started to open somewhen between anomaly 24 and 25. Soon after these discoveries the "Glomar Challenger" of the Deep-Sea Drilling Project visited the Norwegian-Greenland Sea during DSDP Leg 38, led by co-chief scientists Manik Talwani and Gleb Udintsev, to address 4 scientific questions, namely 1) the tectonic framework and evolution of the area, 2) the youngest times of the existence of land bridges between Eurasia and North America, 3) the date of initiation of northern hemisphere glaciations, and 4) to find Tertiary microfaunas and -floras. They succeeded splendidly and laid the groundwork for later legs of the "JOIDES Resolution" which under the framework of the International Ocean Drilling Program visited the Norwegian-Greenland Sea during 3 expeditions (Leg 104 —Dipping reflectors of the Vöring Plateau and history of the Norwegian Current, 151 — North Atlantic Arctic Gateways I, 162 — North Atlantic Arctic Gateways II). During Leg 151 the "JOIDES Resolution" even succeeded — accompanied by the icebreaker "Fennica"- to enter ice-free waters to the North of Svalbard thereby bringing a scientific drill ship for the first time into the Arctic Ocean. Lately, ECORD (the European Consortium of Ocean Research Drilling under the framework of the new Integrated Ocean Drilling Program) has organized a major drilling effort in the permanently sea ice-covered central Arctic Ocean by sending a flotilla of 3 ice-breakers (including a drilling vessel) to the Lomonosov Ridge at a position very close to the North Pole (the ACEX expedition led by co-chiefs Jan Backman and Kate Moran).
A host of new data addressing the 4 major themes already defined for DSDP Leg 38 has been collected as results of these drilling efforts. Presently working groups under the auspices of the European Polar Board and various national efforts are attempting to develop plans for a novel research ice-breaker with a drilling capability, the AURORA BOREALIS-project which would allow to conduct systematic drilling programs in many of the permanently ice-covered deep-sea basins of the world ocean.