The lake was ponded by lavas a long time ago.这条湖是很久以前熔岩堵塞河道形成的.Such lavas also once came from the volcanoes in the Cascade Range in Washington.在华盛顿州的喀斯喀特山脉的火山也喷出过这样的熔岩.Previously, researchers had found nearby pillow lava...

n.（火山喷发的）熔岩( lava的名词复数 )，（熔岩冷凝后的）火山岩...

lavas的音标：...