Loma Prieta Earthquake Epicenter - Aptos, CA
Posted by: 
DougK
N 37° 01.869 W 121° 53.227
10S E 598981 N 4098906
The Loma Prieta Earthquake of 1989 caused extensive damage in the San Francisco Bay Area. Freeways collapsed, a section of the bay bridge fell down and fires burned the Marina district. The center of the quake was determined to be in Nisene Marks.
Waymark Code: WMF7BT
Location: California, United States
Date Posted: 09/05/2012
Views: 7
The Loma Prieta Earthquake of 1989 was the largest earthquake, with a magnitude of 6.9 on the Richter scale, in the San Francisco bay area since April, 1906. This major earthquake caused 63 deaths, 3,757 injuries, and an estimated $6 billion in property damage.
Major damages included:
- reinforced-concrete viaducts collapsed on Nimitz Freeway (Interstate 880) in Oakland
- a section of the San Francisco Bay Bridge collapsed
- several houses collapsed or burned in San Francisco's Marina District
- structure damage by liquefaction to buildings, bridges, highways, pipelines, port facilities, airport runways, and levees
The epicenter of the earthquake was determined to be in the Santa Cruz Mountains in the Forest of Nisene Marks
State Park, about 16 kilometers northeast of Santa Cruz and about 7 kilometers south of Loma Prieta Mountains, California.
The epicenter is memorialized by a sign located at the approximate location. Getting to this point requires a hike through the beautiful redwood forest. In the summer, the Aptos Creek Fire Road is open, allowing access to the Porter Family Picnic Area for parking. From here it is about an hour walk to the site on the Aptos Creek Trail. In the winter time, wet weather may cause the fire road to be closed. Parking is then available at the Emmet Reed Picnic Area near the entrance station. From here it requires an additional hour hike.
The fire road is normally closed to cars starting at the Porter Family Picnic Area. From this point, a half hour walk will take you to the Aptos Creek Trail off the fire road. Another half hour walk on a single track trail with a couple of bridgeless stream crossings will take you to the point of the given coordinates.
The location of the sign is on a cliff above Aptos Creek. Across the creek, another cliff rises hundreds of feet higher. This steep ravine is extremely blocked from GPS signals. My GPS receiver ran for 10 minutes using waypoint averaging to get the given coordinates!