Greetings,
I just saw this thread, having been involved in GWX goodness for the last 10 hours.
I do need to clear up the issue of the "leaves". I now believe what I'm seeing that floats on the surface near shores - and further out from time to time is kelp or seaweed ground up when caught by a passing ship's props.
I normally see it in channels and sometimes in harbors but not on a continuous basis.
I've even went as far as to do some coastal navigation and found it again in a few places, normally in a fellow ships wake, and near shore. Unless someone has a better answer, I'm sticking with kelp/seaweed.
As to wrecks on the seafloor, I was in water at 25 meter's depth, so the screen shot posted by jimbuna - especially the ship on the left in the foreground looks eerily similar. If I can find it again, I'll post a screenshot. 8)
Thank you for the compliment about my review.
Cheers,
R.S.