Over het archief
Het OWA, het open archief van het Waterbouwkundig Laboratorium heeft tot doel alle vrij toegankelijke onderzoeksresultaten van dit instituut in digitale vorm aan te bieden. Op die manier wil het de zichtbaarheid, verspreiding en gebruik van deze onderzoeksresultaten, alsook de wetenschappelijke communicatie maximaal bevorderen.
Dit archief wordt uitgebouwd en beheerd volgens de principes van de Open Access Movement, en het daaruit ontstane Open Archives Initiative.
Basisinformatie over ‘Open Access to scholarly information'.
Fluidization of buried mass-wasting deposits in lake sediments and its relevance for paleoseismology: Results from a reflection seismic study of lakes Villarrica and Calafquén (South-Central Chile)
Moernaut, J.; De Batist, M.; Heirman, K.; Van Daele, M.; Pino, M.; Brümmer, R.; Urrutia, R. (2009). Fluidization of buried mass-wasting deposits in lake sediments and its relevance for paleoseismology: Results from a reflection seismic study of lakes Villarrica and Calafquén (South-Central Chile). Sediment. Geol. 213(3-4): 121-135. dx.doi.org/10.1016/j.sedgeo.2008.12.002
In: Sedimentary Geology. Elsevier: Tokyo; Oxford; New York; London; Amsterdam. ISSN 0037-0738; e-ISSN 1879-0968, meer
|  |
| Author keywords |
Fluidization structures; Lake sediments; Reflection seismic profiling; South-Central Chile; Paleoseismology |
| Auteurs | | Top |
|
- Pino, M.
- Brümmer, R.
- Urrutia, R.
|
|
| Abstract |
A dense grid of very-high resolution seismic profiles on Lake Villarrica provides a quasi-3D view on intercalated lenses of low-amplitude reflections, which are connected by acoustic wipe-out patches and fractures to an underlying voluminous mass-wasting deposit. The lenses are interpreted as being created by earthquake-triggered liquefaction in this buried mass-wasting deposit and subsequent sediment fluidization and extrusion at the paleo-lake bottom. These sediment volcanoes are mapped in detail. They have a rather uniform circular geometry and show a linear relationship between apparent width and maximum thickness on a seismic section. The largest sediment volcanoes are up to 80 m wide and 1.9 m thick. Their slope angles designate a syn- to post-depositional sagging of most sediment volcanoes. Sediment volcano detection and mapping from nearby Lake Calafquén further strengthen the revealed geometrical relationships. Locally, some of the sediment/fluid escape structures extend to a higher position in the stratigraphy, which points to a polyphase escape process associated with multiple multi-century spaced strong earthquakes. Thickness and morphology of the source layer seem to exert a dominant control in the production of sediment/fluid extrusions. This study shows that reflection seismic profiling allowed recognizing 4 different seismic events in the studied stratigraphic interval, which are evidenced by mass-wasting deposits and/or fluidization features. |
IMIS is ontwikkeld en wordt gehost door het VLIZ.
