Learn
Every page here is meant to be read once and be enough. Each carries the date a person last re-read its sources and links to those sources, so you can check a claim rather than trust a website.
We do not predict earthquakes and we do not issue warnings. Why, in detail →
- Is there an earthquake right now?
- How to check, and what "right now" means when a catalogue takes minutes to update.
- What magnitude actually measures
- Why M6 is not twice M3, what the letters after the number mean, and why a magnitude changes after publication.
- Intensity: what the shaking felt like
- The Modified Mercalli scale, why it uses Roman numerals, and why one earthquake has many intensities.
- Why earthquake depth matters
- A shallow M4 can be felt more strongly than a deep M6. What depth does to shaking.
- Aftershocks: what to expect
- What the science supports, what it does not, and where USGS publishes its own forecasts.
- What to do during and after an earthquake
- Drop, cover and hold on — and what to do in the hours afterwards.
- How to build an earthquake kit
- What official guidance actually asks for, with quantities.
- Earthquake early warning: ShakeAlert and MyShake
- How seconds of warning are possible, how to receive it, and what it cannot do.
- Earthquake insurance, explained
- Why your homeowners policy excludes it, how the California Earthquake Authority works, and how the deductible is calculated.
- Seismic retrofit, explained
- Bolting, cripple walls, soft storeys, and California’s Earthquake Brace + Bolt grant.
- Can earthquakes be predicted?
- The honest answer, what forecasting can do, and why the idea of a fault being "due" does not hold up.
- It was not an earthquake: booms, blasts and other bangs
- What else shakes a house, and how USGS catalogues them.