Determination of ground displacement of 25 April 2015 Nepal earthquake by GNSS precise point positioning
Bibliographic record
Abstract
The April 2015 Nepal earthquake (known as the Gorkha earthquake) occurred at 06:11:25 (UTC) on the 25th of April, with a magnitude of 7.8Mw. It was the worst natural disaster to strike Nepal since the 1934 Nepal-Bihar earthquake. Precise determination of ground displacement in this area will provide important information to better understand the structure and scope of the earthquake, contributing to faster and more accurate earthquake prediction. In this paper, we use precise point positioning to determine the displacements of 17 GNSS stations around the epicenter for the day of the earthquake. The processing results show that the common displacement direction is close to south-southwest with the largest value being approximately 2 m and the affected area being about 160 km in the southeast direction centered around the earthquake epicenter. 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UNAVCO, 2015, https://www.unavco.org/highlights/2015/nepal.html. USCG, 2015. https://earthquake.usgs.gov/research/everyone/nepal2015/. Zumberge J.F., Heflin M.B., Jefferson D.C., Wattkins M.M. and Webb F.H., 1997. Precise point positioning for the efficient and robust analysis of GPS data from large networks, Journal of Geophysical Research, 102(B3), 5005-5017.
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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 | 0.001 | 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 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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".