Volcanic eruptions spewed thick, white-hot ash, which eventually fused into a layer of dark volcanic rock known as rhyolite.
(Volcanic eruptions; spewed; thick, white-hot ash, which eventually fused into a layer of dark volcanic rock) (thick, white-hot ash; fused; into a layer of dark volcanic rock; T:eventually) (dark volcanic rock; known; as rhyolite)
Volcanic eruptions thick, white-hot ash dark volcanic rock
spewed fused known
thick, white-hot ash, which eventually fused into a layer of dark volcanic rock
into a layer of dark volcanic rock T:eventually
as rhyolite