They are a
regolith breccia consisting mostly of
eucrite and
diogenite fragments, although carbonaceous
chondrules and impact melt can also occur. The rock formed from impact ejecta which was later buried by newer impacts and
lithified due to the pressure from overlying layers.
Regolith breccias are not found on
Earth due to a lack of regolith on bodies which have an
atmosphere. ==Name==