California Department of Transportation District 1
 

Seismic Refraction Survey

Photo from Smith River
A geophone inserted into the soil (4.9M)

Photo from Smith River
The path that was cleared just enough for access (4.5M)

Photo from Smith River
Another section of the path (4.9M)

Photo from Smith River
Betsy charges look like shotgun shells (3.6M)

Photo from Smith River
The Betsy gun is inserted into the soil about 18 inches (5.0M)

Photo from Smith River
A typical reading from the data recorder (4.0M)

Photo from Smith River
Engineering Geologist David Hughes prepares an explosive charge (4.5M)

Photo from Smith River
The explosive charge 'fluffed up' a small area of the sandy soil (4.9M)

Photo from Smith River
Readings from the data recorder are given a quick evaluation to confirm the data is good (3.7M)