Figure and compare the divergence of both types of modeling. The divergence is computed from the wave field components identically. It clearly shows that as expected pure acoustic modeling cannot account for mode converted waves. A realistic modeling of the earth should include mode converted waves (p, sv and sh). Since mode conversions are absent in the pure acoustic modeling, the amplitudes are different of even the ``primary'' waves. No energy is leaking into other modes, but stays within the p wave.

fig1
Marmousi subsurface velocity model.
Figure 1 |

fig6
Elastic modeling with a pressure source recorded into a horizontal receiver.
Figure 2 |

fig7
Elastic modeling with a pressure source recorded into a vertical receiver.
Figure 3 |

fig8
Acoustic modeling with a pressure source recorded into a horizontal receiver.
Figure 4 |

fig9
Acoustic modeling with a pressure source recorded into a vertical receiver.
Figure 5 |

fig3
Divergence computed from elastic modeling schemes. There are mode converted waves. Compare it to the acoustic modeling.
Figure 6 |

fig4
Divergence computed from acoustic modeling schemes. The acoustic modeling does not show mode converted waves.Compare it to the elastic modeling.
Figure 7 |

11/17/1997