This market centers on the total number of earthquakes measuring magnitude 5.5 or greater recorded anywhere on Earth during the seven-day window running from 7 September 2026 to 13 September 2026, with that count compared against a set of discrete numerical thresholds. Earthquakes of this size follow a fairly steady global background rate — the worldwide catalogue typically logs on the order of a dozen such events in any given week — which makes a fixed seven-day window a clean, repeatable benchmark for judging whether seismic activity has run quiet, ordinary, or unusually elevated. Traders are assessing the relative likelihood that the week's confirmed tally lands at, below, or above each threshold, weighing recent seismicity, ongoing aftershock sequences, and the natural variance of global earthquake counts.

1. Market Outcomes and Resolution Criteria: This submarket resolves Yes if the total number of qualifying magnitude 5.5 or greater earthquakes recorded worldwide during the window is exactly 7, and No for any other total. A Tie resolution is possible only under the narrow condition in Rule 5, in which case all positions settle at $0.50 per share.

2. Definition of a Qualifying Earthquake and the Count: A qualifying earthquake is any single seismic event assigned a preferred magnitude of 5.5 or greater by the USGS, with an origin time falling within the window and an epicentre anywhere on Earth. Each distinct catalogued event counts once; separate foreshocks, mainshocks, and aftershocks each count individually where each is independently listed at magnitude 5.5 or above. Magnitude is read to one decimal place from the USGS preferred magnitude — an event listed at exactly 5.5 qualifies, while any event below 5.5 is excluded.

3. Official Sources and Evidence: The sole resolution source is the United States Geological Survey (USGS) Earthquake Hazards Program / National Earthquake Information Center catalogue, queried at earthquake.usgs.gov/earthquakes/search/. The USGS preferred magnitude and origin time are definitive; no other feed, agency estimate, or media report overrides the USGS catalogue.

4. Resolution Timing: The count is taken over origin times from 7 September 2026, 04:00 UTC to 14 September 2026, 03:59 UTC (equivalent to 12:00 AM ET on 7 September through 11:59 PM ET on 13 September 2026). The market resolves once the count is confirmed, no sooner than 24 hours after the window closes. If qualifying events have not yet appeared in the USGS catalogue within 48 hours of the window's close, resolution proceeds on the data available at that time.

5. Data Revisions, Outages, and Threshold Edge Cases: A 24-hour grace period applies to magnitude revisions affecting events on the final day of the window; the catalogue state at the end of that grace period governs. Provisional magnitudes later revised by the USGS to below 5.5 are removed from the count, and events revised up to 5.5 or above are added. The market resolves Tie, with all positions settling at $0.50 per share, only if the USGS catalogue is permanently unavailable and no reliable count can be established from official USGS records after the grace period.

6. Ambiguities and Disputes: Where an event's magnitude sits on the boundary, the USGS preferred magnitude at resolution is decisive, and exactly 5.5 counts. Any conflict between preliminary and reviewed USGS values is resolved in favour of the reviewed (final) USGS catalogue entry.