In uk.sci.weather on Sun, 3 Oct 2004 at 13:03:06, spurious wrote :

I am no mathematician, but for tides to go in and out, the moon must
be displacing million and millions of tonnes of water.
Why then does the gravitation pull on the moon have no effect when it
passes over land?

It does, but since the land is far heavier it doesn't move noticeably.

Another effect the moon's gravity has, is that of slowing the Earth's
rotation over geological time periods.

Basically, the drag of the tides has the same effect on the Earth as
putting your finger on a spinning top, i.e. slowing the spin. The same
effect also causes the moon to move further from the Earth.

At the time of the asteroid impact when the dinosaurs were wiped out,
days were about 20-21 minutes shorter, and there were about 370 days in
the year.

I dare say someone else could give a more technical explanation though.
--
Paul Hyett, Cheltenham