Nick,
I'm very sorry, but I do not understand your questions.
But I can give you a few observations that might help you understand my
work.
(1) The basis of the seaquake theory is that a pod of whales are on a
feeding dive along a mid-oceanic ridge system when a earthquake errupts in
the seafloor below them. The verticial dancing of the rocky bottom acts
likes a giant piston, generating potent changes in the surround water
pressure. The sudden increase/decrease in hydrostatic pressure exceeds the
whales' ability to adjust and causes barotrauma in the pertygoid sinuses.
An injury of this nature disables echonavigation and prevents diving and
feeding due to intense pain.
(2) Without a sense of direction, the pod swims downstream in the path of
least resistance. Oceanic sharks dog the wounded whales like a pack of
wolves trail a herd of reindeer. The whales become too weak and stress to
avoid a stranding after ~25 days lost at sea without food and fresh water.
The current is then able to carry them ashore where they strand, usually at
night.
(3) To determine the earthquake that might be responsible, one must look
back upstream from the beach. While tracing the flow of the current, one
should start looking for a dangerous earthquake that might have occurred
along the way. One should also be looking for a known habitat for the
species in question somewhere along a mid-ocean ridge system. In most
instances, when you back trace the current to a known habitat, you will find
3 or 4 earthquakes of ~5 magnitude or better. The focus of these events are
usually less than ~10 km deep in the seabed.
(4) Not all magnitude 5 earthquakes produce dangerous seaquakes.
Earthquakes with predominate horizontal movement do not produce dangerous
pressure changes because motion horizontal to the surface produces a
shearing action. The rocky bottom simply slides through the water like a
paddle turned sideways. Only vertical thrusting produces dangerous seaquake
waves.
(5) Magnitude of the earthquake is not the controlling factor.. Seaquakes
(pressure waves in the water) are generated by rapid vertical thrusting in
the seafloor. The intensity of the seaquake wave depends on the speed of
the vertical thrusting, not the magnitude.
(6) The deeper the focus the earthquake, the less likely it is to injury
whales.
I hope this helps.
Warm Regards,
Dave Williams
----- Original Message -----
From: "Nick Tregenza" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, January 05, 2010 6:21 PM
Subject: Re: [ECS-TALK] Comments on recent pilot whale strandings on eastern
coast of Canada
> David,
>
> Have you tried looking for quakes for a set of strandings that you've
> never examined previously in which half have had their dates moved by a
> year?
> I'm asking because it's an interesting hypothesis, but without knowing how
> often explanatory quakes are available by chance within the huge circles
> of influence you allow it's impossible to know whether it means something
> or nothing at all.
>
>
> Nick
>
>
> --
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Nick Tregenza
> Chelonia Limited
> 5 Beach Terrace
> Long Rock
> Cornwall
> TR20 8JE
> UK
>
>
> www.chelonia.co.uk
> C-POD software www.chelonia.co.uk/cpod_downloads.htm
> [log in to unmask]
> tel +44 1736 711783 mob 07871 393 285
> fax +44 (0)8700 554967
> _________________________________________________________________________
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How to join/leave the ECS-TALK list, how to obtain a Listserv Password,
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