Die Inhalte dieser Seite sind leider nicht auf Deutsch verfügbar.
Seitenpfad:
Trigger and failure mechanisms of gravitational mass movements: Neotectonics - sediment physics - fluid activity
A. Kopf, K. Huhn, C. Spiegel,
A. Boetius, A. Hüpers, T. Pichler, V. Spiess
The key research target of this project is the understanding of pore pressure transients both as a proxy for strain and as a phenomenon that strongly controls sediment dynamics. This spans processes such as fluid-particle interaction on a small to medium scale and large-scale phenomena such as evolution of landslide failure plains, fault activity, or mud volcanic episodicity. Coevally, decreasing sediment strength, e.g. weakening of soft clays or liquefaction of loose granular silts and sand caused by cyclic loading (e.g. earthquakes) is a major player in sediment failure, while material strengthening may also be favored by cyclic loading.
As sediment strength and fluid pressure counteract, marine sediments behave as a sensitive, metastable two-phase system of solids and fluids. Processes acting during and prior to sediment failure as well as their governing parameters (e.g. permeability) rely on a thorough knowledge of a suite of geotechnical parameters, which have also repercussions on fluid venting and ecosystems within or on the seafloor (see Research Area GB). As a consequence of the complexity and analytical challenges, we aim at the improvement of seagoing devices, ideally for observatories, but also of laboratory instruments and numerical modeling codes and routines.
This project follows a multidisciplinary approach comprising
A. Boetius, A. Hüpers, T. Pichler, V. Spiess
The key research target of this project is the understanding of pore pressure transients both as a proxy for strain and as a phenomenon that strongly controls sediment dynamics. This spans processes such as fluid-particle interaction on a small to medium scale and large-scale phenomena such as evolution of landslide failure plains, fault activity, or mud volcanic episodicity. Coevally, decreasing sediment strength, e.g. weakening of soft clays or liquefaction of loose granular silts and sand caused by cyclic loading (e.g. earthquakes) is a major player in sediment failure, while material strengthening may also be favored by cyclic loading.
As sediment strength and fluid pressure counteract, marine sediments behave as a sensitive, metastable two-phase system of solids and fluids. Processes acting during and prior to sediment failure as well as their governing parameters (e.g. permeability) rely on a thorough knowledge of a suite of geotechnical parameters, which have also repercussions on fluid venting and ecosystems within or on the seafloor (see Research Area GB). As a consequence of the complexity and analytical challenges, we aim at the improvement of seagoing devices, ideally for observatories, but also of laboratory instruments and numerical modeling codes and routines.
This project follows a multidisciplinary approach comprising
- state-of-the-art geotechnical laboratory tests, design and use of in-situ seagoing devices, and
- numerical modeling using parameters derived by the former ones.
Expeditions
- FS SONNE Expedition SO-222b (04.07. - 18.07.2012)
- FS SONNE Expedition SO-222a (09.06. - 30.06.2012)
- FS POSEIDON Expedition P429 (21.03 - 08.04.2012)
- FS POSEIDON Expedition P410 (12.03. - 01.04.2011)
- DV Chikyu IODP Expedition 333 (13.12. - 10.01.2011)
- DV Chikyu IODP Expedition 332 (25.10. - 11.12.2010)
- FS MARIA S. MERIAN Expedition MSM 15/3 (04.06. - 05.07.2010)
- FS POSEIDON Expedition P387 (18.06. - 06.07.2009)
- DRV Chikyu Expedition 319 (10.05. - 31.08.2009)
- DS Chikyu IODP Expedition 316 (19.12. - 05.02.2008)
- FS METEOR Expedition M73/1 /21.07. - 11.08.2007)
With this strategy we aim to
- drill in the key research areas using MeBo or by IODP (Cretan Sea, Ligurian margin),
- conduct amphibic work onshore where access to active faults (Cretan Sea) or mud domes juxtaposing faults (Azerbaijan, Japan) exists, and
- use and improve in-situ tools to gather time series of physical properties in areas of fluid-sediment interaction triggering landslides and other geohazards.
- complement these data by cosmogenic nuclides for dating fault activity and landslide emplacement.