n.火山作用
The volcanism is strong in Cenozoic and has several periods. 凹陷中新生代火山作用強(qiáng)烈，也具有多期性。
The formation of auriferous strata was controlled by volcanism and eustacy. 火山作用和海平面變化對(duì)含金地層的形成起到了控制作用。
