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Figure 1 (A)– Principles of S-wave splitting in a fractured rock. The incident
S wave splits into two components – S1 and S2 – that transmit through
a fracture zone and reflect individually from fracture-bounding interfaces.
S1 is the fast-S mode, and its particle-displacement vector is oriented
parallel to the fracture planes. S2 is the slow-S mode, and its particledisplacement
vector is oriented perpendicular to the fracture planes.
Reflected modes are not shown.
Figure 2 (B)– Laboratory
through a simulated