Breccia

Breccia (/ˈbrɛtʃiə, ˈbrɛʃ-/) is a rock composed of large angular broken fragments of minerals or rocks cemented together by a fine-grained matrix.

The word has its origins in the Italian language, in which it means "rubble". A breccia may have a variety of different origins, as indicated by the named types including sedimentary breccia, fault or tectonic breccia, igneous breccia, impact breccia, and hydrothermal breccia.

A megabreccia is a breccia composed of very large rock fragments, sometimes kilometers across, which can be formed by landslides, impact events, or caldera collapse.