The 16 March 1999 mN 5.1 Cote-Nord Earthquake: The Largest Earthquake Ever Recorded in the Lower St. Lawrence Seismic Zone, Canada
Bibliographic record
Abstract
Other| March 01, 2004 The 16 March 1999 mN 5.1 Côte-Nord Earthquake: The Largest Earthquake Ever Recorded in the Lower St. Lawrence Seismic Zone, Canada Maurice Lamontagne; Maurice Lamontagne Natural Hazards Program Natural Resources Canada 588 Booth Street Ottawa, Ontario Canada K1A OY7 malamont@nrcan.gc.ca (M.L.) Search for other works by this author on: GSW Google Scholar Allison L. Bent; Allison L. Bent Geological Survey of Canada 7 Observatory Crescent Ottawa, Ontario Canada K1A OY3 (A.L.B., C.R.D.W., S.M., V.R) Search for other works by this author on: GSW Google Scholar Catherine R. D. Woodgold; Catherine R. D. Woodgold Geological Survey of Canada 7 Observatory Crescent Ottawa, Ontario Canada K1A OY3 (A.L.B., C.R.D.W., S.M., V.R) Search for other works by this author on: GSW Google Scholar Shutian Ma; Shutian Ma Geological Survey of Canada 7 Observatory Crescent Ottawa, Ontario Canada K1A OY3 (A.L.B., C.R.D.W., S.M., V.R) Search for other works by this author on: GSW Google Scholar Veronika Peci Veronika Peci Geological Survey of Canada 7 Observatory Crescent Ottawa, Ontario Canada K1A OY3 (A.L.B., C.R.D.W., S.M., V.R) Search for other works by this author on: GSW Google Scholar Author and Article Information Maurice Lamontagne Natural Hazards Program Natural Resources Canada 588 Booth Street Ottawa, Ontario Canada K1A OY7 malamont@nrcan.gc.ca (M.L.) Allison L. Bent Geological Survey of Canada 7 Observatory Crescent Ottawa, Ontario Canada K1A OY3 (A.L.B., C.R.D.W., S.M., V.R) Catherine R. D. Woodgold Geological Survey of Canada 7 Observatory Crescent Ottawa, Ontario Canada K1A OY3 (A.L.B., C.R.D.W., S.M., V.R) Shutian Ma Geological Survey of Canada 7 Observatory Crescent Ottawa, Ontario Canada K1A OY3 (A.L.B., C.R.D.W., S.M., V.R) Veronika Peci Geological Survey of Canada 7 Observatory Crescent Ottawa, Ontario Canada K1A OY3 (A.L.B., C.R.D.W., S.M., V.R) Publisher: Seismological Society of America First Online: 09 Mar 2017 Online ISSN: 1938-2057 Print ISSN: 0895-0695 © 2004 by the Seismological Society of America Seismological Research Letters (2004) 75 (2): 299–316. https://doi.org/10.1785/gssrl.75.2.299 Article history First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Maurice Lamontagne, Allison L. Bent, Catherine R. D. Woodgold, Shutian Ma, Veronika Peci; The 16 March 1999 mN 5.1 Côte-Nord Earthquake: The Largest Earthquake Ever Recorded in the Lower St. Lawrence Seismic Zone, Canada. Seismological Research Letters 2004;; 75 (2): 299–316. doi: https://doi.org/10.1785/gssrl.75.2.299 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietySeismological Research Letters Search Advanced Search Abstract On 16 March 1999 at 12:50 UT, a moderate earthquake of mN 5.1 occurred in the Lower St. Lawrence Seismic Zone (LSZ), 60 km south of Sept-Îles, Québec. Due to its location under the St. Lawrence River, more than 50 km away from inhabited areas, the earthquake was named the Côte-Nord earthquake (the French name for the Quebec North Shore region along the St. Lawrence River). In this zone, approximately 60 events are located yearly; historically, only one earthquake was nearly as large as the Côte-Nord event. Felt up to 300 km distant, the mainshock did not cause any damage. Peak ground accelerations of 0.22 g and 0.13 g were measured at epicentral distances of 130 km and 360 km by digital accelerographs. Three different determination methods each suggest a depth of approximately 20 km, within the Precambrian basement. A mixed strike-slip/reverse-faulting focal mechanism was obtained using regional data. Surface-wave inversion suggests a similar solution but with slightly different nodal planes. No foreshock was recorded by the regional network, which has a mN 2.0 detection threshold. The number of aftershocks was anomalously high for a mN 5.1 mainshock; more than 75 aftershocks with mN ranging from 0.9 to 3.5 were recorded in the 30 days following the mainshock. Characteristic parameters of aftershock decay were normal. Within these aftershocks, five doublets and one triplet were found, representing 13 out of 77 events. We interpret the northwest-southeast nodal plane to be the fault plane for the mainshock from the preferred alignment of aftershocks and from the orientation of nearby magnetic and gravimetric lineaments. This orientation is, however, different from the general assumption that northeast-southwest faults are those reactivated in the current local stress field. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.005 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.002 | 0.002 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.002 | 0.000 |
| Research integrity | 0.000 | 0.002 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".