Approximately, 1996, Unocal historian Darwin Sainz mentioned the newly built Union Oil “Oilport” refinery in what is now Shell Beach (between Pismo & Avila Beaches and at 50 to 100 feet elevation) was destroyed by a tsunami in the early 1900’s. July 2009, George Plafker reported, “a bigger earthquake and a more destructive tsunami than the 1964 event are possible in the future”.
The 1812 Santa Barbara Channel earthquake produced 5 tsunami waves approximately 50 feet in height to the front of the Santa Barbara Presidio based on a Franciscan Father’s journal. A book on “Shipwrecks, Smugglers, and Maritime Mysteries” by Wheeler &Kallman reports the largest wave was 48-50 feet estimated by the USGS west of Santa Barbara near Goleta.
The “History of San Luis Obispo County, California” by Thompson & West (1883) reports 12 feet tsunamis occurred on 8-13-1868 (Peruvian earthquake) and 4-16-1877. On 11-22-1878, turbulent water in the absence of wind produced tsunamis that broke over the Morro Bay sand spit (current quad sheet high elevations 66 to 97 feet N to S), destroyed Avila & Pt. Sal piers, damaging Cayucos pier.
A Japanese earthquake resulted in a tsunami at 12:40 PM December 9, 1907, near high tide and in already heavy seas, that stood out from the rest of the storm due to its enormous height. It wrecked the Ventura pier (SLO Tribune) and the Oilport pier (SLO Tribune & Santa Maria Times) at Shell beach and destroyed the Oilport refinery (Darwin Sainz, personal communication).
Before 7 AM on November 26, 1913, tsunami wrecked the Monterey area including waves 10 to15 feet above the Del Monte wharf. At Seaside, “Immense domes of water and foam shot up above the general height” … “appearing from here to be higher than the highest sandhills along the shore.” (current quad sheet high elevations 120 feet).
By Eugene Lou Blanck
Leader Central Coast Earthquake Alliance
California Professional Geologist #3695
California Registered Geophysicist #1011
California Certified Engineering Geologist #1130
California Certified Hydrogeologist #175
California Registered Environmental Assessor #3312
California OES/EMA Disaster Service Worker Trainer SAPS#60672