USGS seeking Loma Prieta felt reports from 35-year-old earthquake

Did you feel shaking from the Loma Prieta earthquake in 1989?

By Communications and Publishing October 8, 2024

‘Did you feel it’ reporting available in multiple languages

MOFFETT FIELD, Calif. — People who felt the magnitude 6.9 Loma Prieta earthquake in the greater San Francisco Bay Area and beyond on October 17, 1989, are encouraged to share what they experienced using the USGS’s “Did you feel it?” reporting tool. Reports can now be filed in Spanish, simplified and traditional Chinese, as well as English.

Map of California in various colors showing the 1 km DYFI responses for the Loma Prieta earthquake

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“The USGS wants to hear about your experience in the 1989 Loma Prieta earthquake if you were in the San Francisco Bay Area at the time,” said Christine Goulet, Earthquake Science Center director. “This type of data collected from the public helps us better understand the impact of past and future earthquakes. While the DYFI survey didn’t exist in 1989, it is now up online within minutes of an earthquake, and we encourage the public to go online to submit their reports following earthquake.”

Felt reports contribute to our understanding of the effects of earthquakes and are used to make detailed maps of shaking. These maps are used by scientists to forecast future shaking that informs emergency response, building codes, and other endeavors to protect life and property.

The Did You Feel It? System was introduced in 1999 and allows individuals to file reports retroactively. As of October 8, 2024, the “Did You Feel It?” had 11,552 responses for the Loma Prieta earthquake. The questionnaire was originally available only in English. The USGS recently added Spanish and Chinese translations.

Felt reports from the 1989 Loma Prieta earthquake are only a small sampling of the people who experienced shaking. The earthquake affected a highly diverse region. Additional responses will allow the distribution of shaking to be mapped in even finer detail, capturing shaking in every neighborhood.

“The anniversary dates of devastating earthquakes are reminders that we live in earthquake country,” said Goulet. ‘The USGS recognizes the tremendous impact that Loma Prieta had on individuals and institutions. While 1989 was long time ago, we still see the value of collecting the population’s input from their experience at the time. This will support better knowledge and preparedness plans.”