Moving deeper, one would expect to find this water transforms into high-pressure ices before… reaching the solid rocky core.

In some cases this would leave behind a bare, rocky core.

A gas giant, it has a rocky core surrounded by an extremely dense atmosphere that would instantly crush any human or spaceship.

The keys shift from barrier islands with rocky cores in the north to coral rock platforms in the south.

Material rigidity of rocky planets and rocky cores of gas planets will cause further deviations from the aforementioned shapes.