Block V: Sources

RDOASP supports the same sources as OASP, i.e explosive sources in fluids or solids or vertical point forces in solids (option X). Multible sources in a vertical array are supported.

Source Types

As in SAFARI the default source type in RDOASP is an explosive type compressional source. In addition to the optional point forces, and some seismic moment sources have been added to RDOASP. The source type is specified by a number (1-5) in the option field (line 2). The translation is as follows:

1.

Explosive source (default) normalized to unit pressure at 1 m distance.

2.

Vertical point force with amplitude 1 N.

3.

Horizontal (in-plane) point force with amplitude 1 N.

4.

Dip-slip source with seismic moment 1 Nm. Dip angle specified in degrees in block V, following the other parameters.

5.

Omnidirectional seismic moment source representing explosive source. Same as type 1, but all three force dipoles have seismic moment 1 Nm.

Source Normalization

In SAFARI-FIPP, the source pulse shape was defined as the pressure pulse produced at a distance of 1 m from the source (for solids the negative of the normal stress 1 m below the source).

In RDOASP, the same source normalization has been maintained for point sources (explosive sources) in fluid media. For solid media, however, the sources are normalized to unit volume (1 m³) injection for explosive sources and unit force 1 N for point sources or 1 N/m for line sources.

User defined Source Arrays

RDOASP allows allow a user-defined source array through options l and v, as described in Section 8.5.3.