| Title | An integrated stratigraphic approach to investigating evidence of paleoearthquakes in lake deposits of
eastern Canada |
| |
| Author | Brooks, G R |
| Source | Geoscience Canada vol. 42, no. 2, 2015 p. 247-261, https://doi.org/10.12789/geocanj.2014.41.063  Open Access |
| Image |  |
| Year | 2015 |
| Alt Series | Earth Sciences Sector, Contribution Series 20140025 |
| Publisher | Geological Association of Canada |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| Related | This publication supercedes Investigating evidence of
paleoearthquakes in lake basin deposits |
| File format | pdf |
| Province | Quebec |
| NTS | 21L; 21M; 21N; 22A; 22B; 22C; 22D; 22E; 22F; 22G; 31I; 31J; 31K; 31L; 31M; 31N; 31O; 31P; 32A; 32B; 32C; 32D; 32E; 32F; 32G; 32H |
| Area | Lac Dasserat; Rouyn-Noranda; Lac Timiskaming; Lac Kipawa; Lac Tee; Lac Petit Ha! Ha!; Lac Jacques-Cartier; Lac Saint-Joseph; Lac Eternité; lac Tadoussac; Grand Lac Squatec; Lac Témiscouata; Berne; Lake
Baldegger; Lake Sarner; Lake Lungerer; Lake Zurich; Lake Lucerne; Lake Seelisberg; Canada; Switzerland |
| Lat/Long WENS | -80.0000 -68.0000 48.0000 45.0000 |
| Lat/Long WENS | 7.0000 9.0000 47.5000 46.5000 |
| Subjects | stratigraphy; geophysics; landslides; landslide deposits; earthquakes; earthquake studies; turbidite sedimentation; turbidites; acoustic surveys; stratigraphic analyses; slumps |
| Illustrations | profiles; tables; plots; location maps |
| Program | Public Safety Geoscience Assessing Earthquake Geohazards |
| Released | 2015 04 10 |
| Abstract | Seismic shaking can generate mass movements, turbidites, and soft-sediment deformation within lake basins. These 'disturbed' deposits may be preserved, and provide a stratigraphic record of
paleoearthquakes. A three-dimensional seismostratigraphy of the lake deposits can be constructed from a high-density, sub-bottom acoustic profile (SAP) survey, allowing disturbed deposits within the basin to be identified and mapped. Event layers
composed of one or more disturbed deposits can be identified within the seismo-stratigraphy, and targeted coring of the lake deposits provides ground-truthing of the disturbed deposits. Analysis of organic or sediment materials sampled from recovered
cores allow ages to be assigned to the event layers. Maps depicting the distribution, extent and types of disturbed deposits within each event layer can be compiled by integrating the event layer stratigraphy and the three-dimensional architecture of
the lake deposits. An intrabasin, multi-deposit event layer is the likely signature of significant past earthquake shaking, but possible non-seismic triggers also need to be assessed. An earthquake catalogue spanning 16 000 years for central
Switzerland exemplifies the results of an integrated seismo- and chrono-stratigraphic approach to paleoseismic investigation. This approach to the investigation of eastern Canadian lake basin(s) has the potential to significantly augment the eastern
Canadian earthquake catalogue. Conversely, the absence of seismically-induced disturbed deposits in SAP profiles and in lake core within a given area can help establish negative evidence of paleoseismicity. |
| Summary | (Plain Language Summary, not published)
This report summarizes a method for reconstructing a record of ancient earthquakes by investigating the occurrence of seismically disturbed deposits
preserved in a fresh-water lake basin. |
| GEOSCAN ID | 293900 |
|
|