Geotechnical properties of siliceous sediments from the Vøring Plateau, Norwegian Sea and the Kerguelen Plateau, Southern Ocean /
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| Other Authors: | , , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1992.
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| Subjects: | |
| Online Access: | Link to OAKTrust copy |
| Abstract: | Cores retrieved from Ocean Drilling Program Legs 104 and 119 reveal that siliceous sediments have relatively high porosities and permeabilities. As expected, undrained shear strengths in siliceous sections are relatively low and largely dependent on the abundance and mineralogy of accessory clays. These characteristics imply that siliceous sediments should be especially prone to slope failures. Laboratory compressibility increases with biogenic silica content and the rate of permeability reduction with consolidation is less for more siliceous sediments. Determinations of plastic limits provides a simple and fairly accurate means of determining biogenic silica content in these sediments. Although siliceous sediments are very compressible in laboratory consolidation tests, they appear to undergo very little in-situ consolidation. As a result, siliceous sediments probably play an important role in the structural development of pelagic dominated, convergent plate margins, characterized by underconsolidated sediments, by maintaining high sediment pore pressures. On the V0ring and Kerguelen Plateaus consolidation state is a function of sedimentation rate and is a useful stratigraphic tool for identifying the presence and nature of unconformities. In conformable sections, siliceous sediments are increasingly underconsolidated with depth. |
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| Item Description: | Typescript (photocopy). Vita. "Major subject: Oceanography." |
| Physical Description: | xii, 151 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references. |