What is an uplifted block bounded by normal faults called?

An uplifted block bounded by normal faults is referred to as a horst. This geological feature is the result of tectonic forces that create vertical displacements along faults. In the context of normal faulting, the land adjacent to the fault line drops down, whereas the area in between or above is uplifted. This contrasting movement creates a relative elevation of the block, forming a horst.

The formation of horsts is significant in structural geology because they often represent areas of new crust that have been pushed upward as a result of tectonic activities. This uplift can expose older rock layers, allowing geologists to study the geological history of the region.

In geological terminology, a 'graben' is the opposite of a horst—it is a block that has dropped down between two normal faults. A 'block' refers more generally to any large piece of crust and does not specify its tectonic movements or position. 'Basement' usually describes the older, often crystalline rocks beneath sedimentary layers, rather than a specific tectonic feature.