The first entry is always the pin's source. Overall confidence is a weighted average of how firmly each reference supports the start and end times used above; a reference counts half as much for every 180 days older than the newest.
The USGS[3] catalogue gives the origin time for event official19060418131226300_12 as 1906-04-18T13:12:26Z, which the narrative states as "05:12 am Pacific Standard Time on Wednesday, April 18, 1906".
Carries the magnitude, local origin time, Mercalli intensity, felt area and death toll that the pin quotes, all cited to USGS[1][3] and state sources.
The USGS's[1] own catalogue entry for this event, the authority for its origin time, magnitude and epicentre.
Something missing or wrong? Say it in your own words: a link that backs this pin up, a different start or end date and why, or a fact it lacks or gets wrong. The AI checks it against this pin's sources, searches for better ones, and adds any page that backs you up. The pin's own sources still count most.