Rolling thunder trucks to send acoustic energy through Seal Beach

Fleets of “vibroseis” trucks will roll through Seal Beach. Courtesy photo

A rolling parade of large trucks capable of sending acoustic energy deep into the Earth will pass through Seal Beach this week, according to a spokesman for L.A. Seismic.

The Los Angeles based company is working on a year-long project to gather seismic and other geophysical data that will map the caverns 15,000 feet below the surface in Seal Beach, Long Beach, Rossmoor and Los Alamitos, according to public relations spokesman Tracey Farmer.

Farmer appeared at the most recent Seal Beach city council meeting to inform city officials that the caravan of “vibroseis” trucks will make stops at specific street locations in Seal Beach from Feb. 7-9.

Over the past several months, the company has been busy burying about 6,000 sensors about 18 inches into the earth throughout the affected area.

Now that the sensors are in place, these special trucks will systematically send acoustic waves deep into the earth at specified locations. The vibrations and sound waves will map the underground caverns and other formations that will be useful for local, state and federal planning, said Farmer.

The trucks, similar to the size of garbage trucks, emit a slight rumble when sound waves are released, said Farmer, but only residents living within 300 feet will notice the activity, he added.

Orange County sheriff’s officials will accompany the trucks throughout the process.

Once the data is gathered, experts with the United States Geological Service and Cal Tech University will be better able to prepare accurate earthquake fault maps and other useful geologic purposes.

Soil liquefaction is also a big issue near the coast, said Farmer. Recent problems in the Huntington Beach area will be studied. In short, when small earthquakes rumble below the surface, the soil in less dense areas create underground sinkholes (soil liquefaction) that must be mapped and studied, said Farmer.

Farmer said fractional earthquake activity takes place under Seal Beach every day but only “rarely” are the small quakes felt.

The energy produced by the trucks combined with the sensors will be calibrated for other commercial purposes, he said. The entire project is being conducted with the assistance of local communities but at no cost to the public.

Residents interested in their exact schedule can check the website