| Outcome | Probability | Yes Bid | Yes Ask | 24h Change | Volume | |
|---|---|---|---|---|---|---|
| Before 2035 | 0% | 0¢ | 0¢ | — | $0 | Trade → |
This market asks whether an earthquake of at least magnitude 8.0 will occur within the defined area of California on or before 2035. The outcome is relevant for risk planning, insurance, infrastructure resilience, and public preparedness.
California lies on an active plate boundary zone with strike-slip faults, transform boundaries, and a northern subduction margin; these tectonic settings produce the state's seismic hazard. Historically the region has experienced very large earthquakes on different timescales (including subduction-zone events in the Pacific Northwest and large historic ruptures within California), but M≥8 events within the modern instrumental record for California are uncommon. Ongoing improvements in seismic monitoring and paleoseismology continue to refine our understanding of where and how very large ruptures can occur.
Market odds represent the collective, time-varying belief of traders about the chance of at least one M≥8 event in the specified place and timeframe; they are not formal scientific forecasts but can incorporate new data and news as they appear. Interpret them as a dynamic indicator that may shift with seismic reports, scientific studies, and major earthquakes elsewhere that change stress conditions or reporting.
Settlement uses the geographic definition specified in the market's official rules; that typically means the U.S. state of California within its political boundaries, but participants should consult the event's rule text for any specific coordinates or inclusion of state offshore waters.
Most modern event determinations rely on the moment magnitude scale (Mw) as reported by authoritative seismological agencies (for example national agencies and recognized research institutions); the market will rely on the agencies named in its settlement rules and on the final/revised magnitudes they publish.
Markets that reference agency reports typically use the final or revised magnitude from the authoritative source named in the rules; therefore later revisions can change whether an event meets the threshold—consult the event settlement policy for how revisions and publication timing are handled.
Whether offshore events count depends on the market's geographic definition; if the epicenter lies within the defined area (including any specified state territorial waters), it would typically qualify—check the event's official geographic boundaries.
Seismologists point to megathrust subduction zones (notably the Cascadia subduction zone along the northern California/northwest margin) as capable of M8–9 events; large continental faults have produced major ruptures, and multi-segment or cascading ruptures on interconnected faults could increase size—assessments depend on fault length, slip rate, and paleoseismic evidence.