Editorial & Corrections Policy
What PlainQuake Publishes
PlainQuake is a data-reference site for earthquakes. Every figure on the site, country, U.S. state, year, and magnitude profiles, rankings, and the significant-earthquake list, is derived from a single public dataset: the USGS Comprehensive Earthquake Catalog (ComCat), maintained by the U.S. Geological Survey Earthquake Hazards Program. We use the worldwide M4.0+ catalog (2005 onward) and the significant M6.0+ catalog (back to 1900).
How the Data Is Sourced and Processed
We query the USGS ComCat web service and ingest the catalog programmatically. The counts, averages, maximum magnitudes, depth statistics, and magnitude distributions you see are computed automatically by our data pipeline directly from the USGS records, they are rendered server-side, not hand-entered or hand-edited. USGS-reported parameters (magnitude, depth, time, location) are reproduced without modification. No seismic value is estimated, interpolated, or editorially adjusted. The plain-language explanations that accompany the figures are written to help readers interpret the catalog; the numbers themselves are derived by script. Full processing details are on our methodology page.
Update Cadence
The USGS catalog updates continuously as new earthquakes are detected and as existing event parameters are refined. We refresh our database periodically to capture new events and magnitude revisions, then re-derive the affected pages from the source. Recent earthquakes may not yet appear if they occurred after our most recent refresh. For real-time information, always consult the USGS Earthquake Hazards Program directly.
How We Handle Corrections
If you find a value that looks wrong, email us at corrections@plainquake.com or use our contact page. Please include the exact page URL, the figure you believe is incorrect, and, if you have it, the corresponding USGS source record. Because every number traces back to the USGS catalog, our correction process is to verify the figure against the source, re-derive the affected page from the catalog, and republish. Where a discrepancy originates upstream in the USGS data itself, we may need to wait for the next catalog revision to correct the underlying record, and we will note the issue in the meantime.
Independence
PlainQuake, does not accept payment, sponsorship, or promoted placement from any government agency, seismological organization, or other party in exchange for how data is presented. Our only revenue source is contextual display advertising served by Google AdSense; advertisers do not influence which entities we cover or how data is shown.
Not Professional Advice
PlainQuake is an informational and educational reference. It does not provide professional engineering, geological, insurance, or emergency-management advice, and it is not an earthquake warning system. For safety decisions and emergencies, consult official sources such as the USGS, FEMA, and your local emergency management agency.
Not Affiliated
PlainQuake is not affiliated with, endorsed by, or connected to the USGS or any government agency.