Gentlemen and Ladies:
Definitions aside, there is such a thing as aseismic slip -- movement on
a fault without associated seismic responses. Look up stroke as in the
medical term and I'm sure you'll find something equally vague relative
to the medical profession's views.
More importantly, and in short, is there a research program to be done
here to quantify and characterize the cause of this Tsunami? Were I
adventurous and in possession of spare time and money, I'd go looking
for old records of the Indonesian seafloor, and then acquire some new
seafloor data. Then one could map the differences to see and
characterize any massive catastrophic debris flows resulting from the
earthquake. Seriously, it seems that not every large earthquake in the
vicinity of the ocean causes a Tsunami. Some folk blame it on the lack
of seafloor fault rupture, but I think Mr. Watterson is on the right
track that submarine slides are likely to blame. Furthermore, this
would probably be equally interesting to stratigraphers I suspect.
Good night,
Joshua C. Turner
BP
-----Original Message-----
From: Tectonics & structural geology discussion list
[mailto:[log in to unmask]] On Behalf Of Martin Walters
MWSoftware
Sent: Thursday, January 20, 2005 12:54 PM
To: [log in to unmask]
Subject: Earthquake
I found these definitions of Earthquake on
WorldNet Dictionary : "shaking and vibration at the surface of the earth
resulting from underground movement along a fault plane of from volcanic
activity".
Dictionary.Com: "a sudden movement of the earth's crust caused by the
release of stress accumulated along geologic faults or by volcanic
activity".
OUP.com (Oxford Dictionary): "a sudden, violent shaking of the earth's
surface"
Personally I don't think that underground and surface has a lot of
impact here, I would prefer the definition to be "shaking and vibration
of the earth resulting from movement along a fault plane or by volcanic
activity", or any other type of activity that causes Earthquakes. This
definition is perfectly acceptable, and gives the KEY phrase "RESULTING
IN".
So I would have thought that both the Earthquake and the Tsunami (in
this
case) are results of slip on a fault. Hence, I would say that the
Earthquake does not cause the Tsunami.
Martin
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