What is an antonym for lithification?

There isn't a single perfect antonym for "lithification," as it describes a complex geological process. However, depending on the context, you could use several terms that represent the opposite of lithification:

* Erosion: The process of wearing away and transporting rock and soil, the opposite of the build-up that lithification represents.

* Weathering: The breakdown of rocks, soil, and minerals through contact with the Earth's atmosphere, water, and biological organisms.

* Degradation: A general term for the process of breaking down or deteriorating, which can be applied to the opposite of lithification.

* Dissolution: The process of dissolving rock or minerals, which is the opposite of the cementation and hardening aspects of lithification.

* Disintegration: The process of breaking down into smaller pieces, which can be used to describe the opposite of lithification in terms of the formation of solid rock.

The best antonym will depend on the specific context in which you are using it. For example, if you are talking about the formation of sedimentary rock, "erosion" would be a good antonym. But if you are talking about the hardening of clay, "dissolution" might be more appropriate.