Answer:
All of these are included in the uniformitarian theories:
1) The Earth's crust has been formed by floods and materials derived from that.
2) The Earth's crust has been formed by current slow processes.
3) Erosion and deposition are currently very slow, but with the time, it affects in a huge way the environment.
4) Major catastrophic processes are possible. They are violent and sudden, and that's how they affect so much the planet.