Estimating Locations and Magnitudes of Earthquakes in Eastern North America from Modified Mercalli Intensities
Bibliographic record
Abstract
We use 28 calibration events (3.7 ≤ M ≤ 7.3) from Texas to the Grand Banks, Newfoundland, to develop a Modified Mercalli intensity (MMI) model and associated site corrections for estimating source parameters of historical earthquakes in eastern North America. The model, \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \[\mathrm{MMI}=1.41+1.68{\times}\mathbf{M}=0.00345{\times}{\Delta}-2.08\mathrm{log}{ }({\Delta}),\] \end{document} where Δ is the distance in kilometers from the epicenter and M is moment magnitude, provides unbiased estimates of M and its uncertainty, and, if site corrections are used, of source location. The model can be used for the analysis of historical earthquakes with only a few MMI assignments. We use this model, MMI site corrections, and Bakun and Wentworth's (1997) technique to estimate M and the epicenter for three important historical earthquakes. The intensity magnitude M I is 6.1 for the 18 November 1755 earthquake near Cape Ann, Massachusetts; 6.0 for the 5 January 1843 earthquake near Marked Tree, Arkansas; and 6.0 for the 31 October 1895 earthquake. The 1895 event probably occurred in southern Illinois, about 100 km north of the site of significant ground failure effects near Charleston, Missouri. Manuscript received 14 March 2002.
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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| 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".