Other late-stage solutions form coarse-grained igneous rock known as pegmatite, which is rich in feldspar ... The warm water is lighter and more chemically active and rises up (convects) through the fractured rocks ... The mineral material is either produced directly from the igneous parent rock or altered by metamorphic
Cretaceous or Early Cenozoic Periods. ... They also have higher contents of volatiles than igneous meteorites. ... 1000 meters below the surface but is exposed within the crater due to late-stage uplift accompanying