| Title | Empirical geophysical/geotechnical relationships in the Champlain Sea sediments of Eastern Ontario |
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| Author | Crow, H L ;
Hunter, J A; Pugin, A J -M; Pullan, S E; Alpay, S; Hinton, M |
| Source | Landslides in Sensitive Clays: From Geosciences to Risk Management
; by L'Heureux, J -S (ed.); Locat, A (ed.); Leroueil, S (ed.); Demers, D (ed.); Locat, J (ed.); Advances in Natural and Technological Hazards Research vol. 36, 2013 p. 253-264, https://doi.org/10.1007/978-94-007-7079-9 20 |
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| Year | 2013 |
| Alt Series | Earth Sciences Sector, Contribution Series 20120459 |
| Publisher | Springer Netherlands |
| Meeting | 1st International Workshop on Landslides in Sensitive Clays; Laval; CA; October 28-30, 2013 |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Ontario |
| NTS | 31G/05; 31G/06; 31G/07; 31G/10; 31G/11; 31G/12 |
| Area | Eastern Ontario; Champlain Sea; Ottawa |
| Lat/Long WENS | -76.0000 -74.5000 45.7500 45.2500 |
| Subjects | geophysics; engineering geology; surficial geology/geomorphology; clays; clay analyses; sensitive clays; terrain sensitivity; conductivity; slope failures; slope stability; slope stability analyses;
slope deposits; geophysical surveys; seismic interpretations; seismic models; seismic surveys; Champlain Sea Sediments |
| Illustrations | location maps; profiles; plots |
| Program | Public Safety Geoscience Eastern Canada Geohazards Assessment Project |
| Released | 2013 07 12 |
| Abstract | Geophysical and geotechnical data are presented from different sites in eastern Ontario where variable geotechnical properties of Champlain Sea sediments ('Leda Clays') are found. Sites range from thick
"undisturbed" silts and clays, to "disturbed" geologically similar soils (earthquake triggered landslides and other deformed materials). High-resolution seismic profiles provide stratigraphic
context for some of the boreholes drilled in the study
area. Downhole geophysical logs from fourteen boreholes are compared to core sample measurements of porosity, sensitivity, and porewater conductivity to develop useful empirical relationships. According to these relationships, silt and clay sediments
can be sensitive or quick when formation conductivity drops below 100 mS/m. Conversely, silts and clays with elevated conductivities (>250 mS/m) are rarely sensitive. Salinity values calculated from porewater conductivity indicate sensitive or quick
behaviour may be expected in leached soils when salinity drops below 2 g/l. |
| Summary | (Plain Language Summary, not published)
Empirical equations relating geophysical measurements to potentially problematic geotechnical behaviour in soft soils of the Champlain Sea ('Leda Clays')
are presented from 14 borehole sites in eastern Ontario. Equations were developed by relating downhole conductivity and velocity data to core sample measurements of porosity, sensitivity, and porewater conductivity. These equations may help predict
soil sensitivity, an important parameter in landslide hazard assessment. |
| GEOSCAN ID | 292391 |
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