>> it is quite possible that there's currents down there which could have disturbed the debre and also as it was falling from the surface it would have dispersed over a large area, as well. it has been said we know more about the surface of the moon than the seabed of the ocean floor. that's probably right. we don't have accurate sampling of the currents in that particular area. the indication we have that silt is on the seabed is taken from samples taken some years ago and 130 miles away from the current position. they are in a database that we can access but gives an understanding of how little topography we have of the seabed. the concept of water movements an flows down there is one we have to take in to account.