#11 black pixels appearing on the mountains

[Karla Stenger]

this effect is caused after two plates collide and
mountains are grown, then after some erosions you will
notice some black holes growing in the middle of
mountains which is not desireable.
In some degree, the DOGROUP option fixes it, but still...

I think it has to do with how plates collide, leaving
little holes in between. Another option but less
probable is that it has to do with the erosion
itself... I have to re read that to be sure.