| Table 16 | ||
| SEISMIC ZONE DESCRIPTION | ||
| SEISMIC ZONE | GENERALIZED GEOLOGIC FORMATIONS | AMPLIFICATION OF SHAKING |
| *V1 | Moderately thick section of marine and continental sedimentary deposits overlying the granitic basement complex | Amplification of shaking that would affect low to medium- rise structures is relatively high but the distance to either of the fault systems that are expected sources of the shaking is sufficiently great that the effect should be minimal |
| *V2 | " " " | Amplification of shaking that would affect low to medium- rise structures is low and the distance to the San Andreas fault zone is moderate. The combined effect is that shaking is expected to be minimal |
| *V3 | Thick section of marine and continental sedimentary deposits results in a moderate increase in expected shaking over that for the east side of the valley | Amplification of shaking is reduced by the damping effect of the thick sedimentary section, but the moderate proximity of the San Andreas fault zone |
| *V4 | Thick section of consolidated sedimentary units overlain by thick unconsolidated alluvial fan deposits | Amplification of shaking is reduced by the damping effect of the thick sedimentary section, but its moderately close proximity to the San Andreas fault zone results in the expectation of moderately high shaking characteristics |
| **C1 | Thick section of consolidated sedimentary units, with a high frequency of exposure characteristics | Amplification of shaking is low because of the firm nature of the surface in this area. But, because of its close proximity to the San Andreas fault zone, the combinationresults in moderate to moderately high shaking |
| **C2 | Moderately thick section of marine sedimentary rock unit with a high frequency of exposure throughout the area, with some metamorphics locally,which are of minor importance | Amplification is low, but the close proximity of the San Andreas fault zone should result in moderately high to high shaking characteristics |
| * Valley Floor Seismic Zone | ||
| ** Coastal Range Seismic Zone | ||
| Source: 1974 Five County Seismic Safety Element | ||