Figure 4. Spectral densities associated with various types of sources.
In each graph, curves 1-4 correspond to
L=lc, 10lc, 102lc and
103lc , respectively. (a) Piezo-magnetic source,
lc=10-3 m.
(b) Electro-kinetic source,
lc=0.1 m,
mv=10-12 m2, curve (0) corresponds
to
L=lc with no diffusion term. (c) Electro-kinetic source, same as (b)
except that
lc=10 m. (d) Piezo-electric source,
lc=10-3 m,
VS=3103 m/s,
partially ordered grains. (e) Piezo-electric source,
lc=10-3 m,
VS=3
103 m/s, randomly oriented grains.