"miskairal" wrote in message u...
I'm hopeless at distance but I can tell you this, that sand was always
submersed in water although at low tide I was only up to about my hips
and at high tide I couldn't even swim out that far. That's Hervey Bay,
when the tide it out it is out for what seems like miles.

Your experience does not match what Shimek has stated...
I need to find some technical paper on this - but where ? :-)

Thanks for a link to another forum I can spend time at

You are welcome :-