Earthquake Information

Chronological Earthquake Index

Lompoc Earthquake

TIME: November 4, 1927 / 5:49 am, PST
LOCATION: 33° 43' N, 120° 46' W in the Lompoc area, about 16 km (10 miles) offshore
MAGNITUDE: ML7.1
TYPE OF FAULTING: uncertain
FAULT INVOLVED: uncertain; possibly the Hosgri Fault

The earthquake of November 4, 1927 was one of the most powerful shocks in southern California this century. Fortunately, it occurred in a reasonably spasely populated area, and some distance offshore, so damage was lighter than would be expected for a quake of such magnitude. In the area nearest the epicenter (the coastal area near the town of Surf), people were thrown from standing and reclining positions, a concrete highway was cracked, a railroad bridge was thrown out of line, and sand and water were fountained from the ground, leaving behind up to twenty "sand craters".

This earthquake also produced a sea-quake (compressional shock transmitted by water) and a seismic sea wave. The sea-quake was so violent it killed and stunned fish near Point Arguello and shook at least two ships in the area: the S.S. Socony and the Alaska Standard. Neither was seriously damaged, however.

The seismic sea wave (tsunami) produced by the shock was approximately 2 meters high at Surf and Pismo Beach and was recorded from La Jolla (near San Diego) to Fort Point (near San Francisco). The first wave was recorded as positive (not preceded by recession of water) at all the California coastal stations that noted it.

No deaths or major injuries (excepting those of ocean fish) were reported in connection with this earthquake.

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