Well, that area has had similar events before. See what excessive TV
coverage of quake disasters cause. Now the government has to contend with
people griping about whether a tsunami warning should have even been issued.
Hearing that EBS alert on the radio yesterday due to an earthquake and
tsunami threat was quite exciting. I've heard those before but they were
always attributed to amber alerts and severe weather - never heard one for a
quake. Anyway....

But I really wanted to point out something else, although a bit different
from Keith's contribution. I discovered that yesterday's M7 event left a
smaller signature on my drum while the M7 Hector Mines event in 1999 left a
more dramatic one. Both events were very similar in magnitude (the MFZ event
may have been a bit larger M7.2) and both are just about similar distances
from my recording station. But I'm not sure why the seismogram signatures
are sooooo different. The 1999 Hector event saturated my record for about
six to seven minutes while yesterday's off-shore event never saturated,
although the durations were about the same.

My system is a short period sensor L4 geophone. The Gain was set at 30dB
during the 1999 and yesterday, it was either at 18 or 24dB.

Could it be that the MFZ event was submarine and the Hector Mines event was
not? I dunno.

What do you think?

Kareem 

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