1. Batholith: A very large, irregularly shaped mass of intrusive igneous rock that covers at least 100 square kilometers. Batholiths are often formed by the accumulation of multiple magma chambers over time. Examples include the Sierra Nevada Batholith in California.

2. Stock: Similar to a batholith but smaller, covering less than 100 square kilometers. Stocks are often found within batholiths or associated with them.

3. Dike: A tabular, discordant intrusive body that cuts across existing rock layers. Dikes are typically relatively thin and can extend for considerable distances. They often form when magma is injected into cracks or fractures in the surrounding rock.

4. Sill: A tabular, concordant intrusive body that is parallel to existing rock layers. Sills are typically injected between layers of sedimentary rock or volcanic flows. They can be quite extensive and often form layers of igneous rock within the surrounding rock sequence.