Surface Waves: Source and Path Properties

The seismic surface wave contains information about the depth of the source. To extract this information, the effect of propagation must be known. We find that unconsolidated sediments can effectively erode the short period energy. The results of this study suggest that much care must be taken before the absence of short period surface waves is interpreted as an effect of focal depth. Deep earthquakes definitely exhibit a different Rayleigh wave amplitude than shallow events. In addition, a higher mode Rayleigh wave appears to dominate the long period vertical record. We conclude that both phenomena may be used as a depth diagnostic. We failed to confirm the utility of source phase for identifying deep events. The source phase may be useful for resolving shallow depth events.