initial volcanism造句

Initial volcanism of the NCVP 20 million years ago was sporadic, producing small volumes of material.
Initial volcanism produced a } } thick sequence of columnar jointed alkali basalt flows and altered grey-green vesicular basalts which form the lowest unit.
Evidences of Emeishan volcanology suggest that the initial volcanism of the central ELIP occurred in a deep submarine environment without any significantly pre-volcanic uplift.
It's difficult to find initial volcanism in a sentence. 用initial volcanism造句挺难的