Interdisciplinary Approaches to Geoscience on the North East Atlantic Margin and Mid-Atlantic Ridge
Author | : N. H. Kenyon |
Publisher | : |
Total Pages | : 158 |
Release | : 2001 |
Genre | : Acoustic imaging |
ISBN | : |
The areas visited during the 10th Training-through-Research Programme were the Portuguese Margin, the Gulf of Cadiz, the Lucky Strike area of the Mid-Atlantic Ridge, the Rockall Trough, the Southern Faeroe margin, and the Varring Plateau (Norwegian margin). The investigations were aimed atstudying such geological processes as neotectonics, fluid migration and escape, sediment processes in canyons and sediment reworking and benthic biology in areas swept by deep-sea bottom currents as well as hydrothermal manifestations on mid-ocean ridges. A seismic and sidescan survey of the Marques de Pombal structure (Portuguese margin) allowed a better understanding of a fault system known here from previous studies such as the ARRIFAN0 and BIGSET projects. The fault pattern has been mapped and acoustic images have helped to evaluate the status of their activity. The Marques de Pombal structure showed little evidence of recent activity and is being covered by sediments. Shallow slides found in the vicinity of the structure may, however, indicate some occasional activity disturbing the overlying sedimentary cover. The Pereira de Sousa fault was found to be much more active. Six new mud volcanoes were discovered and studied in the Gulf of Cadiz. Most of them were proved to be recently active. The mud volcanism of the Gulf of Cadiz can be considered as two characteristic regions with different mud breccia lithological composition. Several types of lava sulphite ores sampled during the Azores campaign of Leg 2 allowed a better understanding of volcanic evolution and associated processes of this area. A short 3.5 kHz survey across the Porcupine Seabight mouth, combined with existing swath bathymetry data and a few cores from the area, confirmed the findings of the TTR-7 cruise that the Gollum channel system is currently inactive. The study of a canyon on the northeastern Rockall Trough margin showed that the system is inactive at the present time and the last pulse of active downslope sediment transport took place in immediate pre-Holocene time. Debris flows were found mostly on the flanks of the canyon while the axial zone showed numerous signs of erosion. Sand was not particularly common in the studied area. It is suggested that significant amounts of sand are trapped in the canyon head, possibly due to slumps blocking the narrower waist area. Abundant traces of seabed erosion found immediately beyond the canyon mouth indicate that this area is a bypass zone and sand deposition may occur further into the canyon mouth indicate that this area is a bypass zone and sand deposition may occur further into the basin plain. An extensive collection of TV-guided grab samples and seafloor video records, obtained from sites in the Northern Rockall Trough, Wyville-Thomson Ridge and Southern Faeroe Plateau, provided GOOd insight on the distribution of bottom fauna, including deep-water corals, and of coarse glaciagenie debris. New data on a BSR distribution pattern were obtained on the southeastern part of the Verring Plateau and they suggest that the formation of the Storegga Slide was not directly related to the dissolution of gas hydrates. The investigation also provided a new insight into gas hydrate formation and distribution in the area.
Global Ocean Science Report
Author | : Intergovernmental Oceanographic Commission |
Publisher | : UNESCO Publishing |
Total Pages | : 247 |
Release | : 2020-12-14 |
Genre | : Political Science |
ISBN | : 9231004247 |
The world ocean is a life-supporting system for humanity, yet it remains largely unknown. Based on data collected from around the world, the Global Ocean Science Report 2020 offers a global record of how, where and by whom ocean science is conducted. It monitors our capacity to understand the ocean and seize new opportunities. More generally, the Report underlines the essential role of ocean research and international cooperation for all key issues of the 21st century.
Reviews of Environmental Contamination and Toxicology
Author | : George W. Ware |
Publisher | : Springer Science & Business Media |
Total Pages | : 167 |
Release | : 2012-12-06 |
Genre | : Science |
ISBN | : 1461223024 |
Reviews of Environmental Contamination and Toxicology provides detailed review articles concerned with aspects of chemical contaminants, including pesticides, in the total environment with toxicological considerations and consequences. RAJ GROVER, JEFFREY D. WOLT, ALLAN J. CESSNA, AND H. BRUNO SCHIEFER: Environmental Fate of Trifluralin JEFFREY D. WOLT: Environmental Fate of Ethalfluralin ALFONSO V. BOTELLO, SUSANA VILLANUEVA F. AND GILBERTO DIAZ G.: Petroleum Pollution in the Gulf of Mexico and Caribbean Sea
Multidisciplinary Study of Geological Processes on the North East Atlantic and Western Mediterranean Margins
Author | : N. H. Kenyon |
Publisher | : |
Total Pages | : 140 |
Release | : 2000 |
Genre | : Continental margins |
ISBN | : |
Technical Series
Author | : Intergovernmental Oceanographic Commission |
Publisher | : |
Total Pages | : 136 |
Release | : 1996 |
Genre | : Oceanography |
ISBN | : |