Structure and Development of the Greenland-Scotland Ridge

A group of geoscientists from a number of NATO countries met under NATO sponsorship in Copenhagen on February 27 and 28, 1978, and formulated a proposal entitled "EVOLUTION OF THE GREENLAND­ ICELAND-FAEROE-SCOTLAND RIDGE, A KEY AREA IN MARINE GEOSCIENCE". This part of the North Atlantic Ocean is of particular interest because of its anomalously shallow bathymetry which has profoundly influenced many aspects of the evolution of the North Atlantic. The proposed investigations therefore aim to study the deep crustal structure including relationship of continental and oceanic crust, history of subsidence of the ridge including its past role as a land bridge, age of the oceanic basement along it and its history of formation, and the influence of the ridge on Tertiary and Quaternary depositional palaeoenvironments. In furtherance of this proposal, it is intended to carry out a series of seismic and drilling operations on the Ridge during the coming years. These major marine investigations will be mainly funded from national sources. An important preliminary stage to the project is the collec­ tion and synthesis of available data. NATO has already approved a small budget for this purpose which has enabled a geoscientist to work partly at the Department of Geological Sciences of Durham University, UK, and partly at Lamont-Doherty Geological Observatory of Columbia University, Palisades, USA, for about six months to compile the data. The most important map showing magnetic anomalies and lineations in the area, is included in a pocket at the back of this volume.

Contenu

1: Review of Geophysical Knowledge.- Deep Structure and Geodynamics of the Greenland-Scotland Ridge: An Introductory Review.- Plate Tectonic Evolution of the Greenland-Scotland Ridge and Surrounding Regions.- Crust and Upper Mantle Beneath Iceland.- The Crust Beneath the Iceland-Faeroe Ridge.- Geology and Crustal Structure of the Faeroe Islands-A Review.- Aspects of the Tertiary Geology of the Faeroe-Shetland Channel.- Faeroe-Shetland Escarpment and Continental Margin North of the Faeroes.- Ocean Continent Boundary under the Norwegian Continental Margin.- Structure and Origin of the Wyville-Thomson Ridge.- Davis Strait: Structures, Origin and Evolution.- The Iceland Mantle Plume: Status of the Hypothesis after a Decade of New Work.- 2: Review of Techniques.- New Methods in Marine Geology and Geophysics that have Application to the Study of Greenland-Scotland Ridge.- The Seismic Reflection/Refraction Method: Wide Aperture Data Obtained in Multiship Experiments.- Ocean-Bottom Seismographs.- Aspects of Bottom Boundary Layers in the Ocean.- 3: Review of Geological Knowledge.- Outstanding Geological Problems of the Greenland-Scotland Ridge: An Introduction.- Rare Earth Geochemistry of Iceland Basalts: Spatial and Temporal Variations.- Silicic Basalts from the Faeroe Islands: Evidence of Crustal Contamination.- Cenozoic Paleogeography of North Atlantic Land Bridges.- Fossil Evidence of Early Tertiary North Atlantic Events Viewed in European Context.- Biostratigraphy of Interbasaltic Coals from the Faeroe Islands.- Geology of the Greenland-Iceland Ridge in the Denmark Strait.- Speculations about the Paleodepth of the Greenland-Scotland Ridge during Late Mesozoic and Cenozoic Times.- Influence of the Greenland-Scotland Ridge on the Geological History of the North Atlantic and Norwegian-Greenland Sea Areas.- Sediment Transport Mechanisms at NE Atlantic Margins: Evidence from the Magnetic Anisotropy of IPOD Cores.- Cenozoic Marine Environments in the North Atlantic and Norwegian-Greenland Sea.- Development of Cenozoic Abyssal Circulation South of the Greenland-Scotland Ridge.- On the Late Pleistocene Exchange of Water Across the Icelandic Transverse Ridge.- Geological History of the Iceland-Faeroe Ridge and its Influence on Pleistocene Glaciations.- Terrigenous Late Quaternary Sediment Components North and South of the Scotland-Greenland Ridge and in the Norwegian Sea.- The Modern Current Regime Across the Greenland-Scotland Ridge.- 4: Conclusions.- Discussion, Conclusions and Recommendations.- Magnetic Anomalies over Iceland and Surrounding Seas (Text to Accompanying Map).