new smoker with rocks in it

I have a new smoker which has some rocks I it, I think they call them lava rocks. I want to put some chunks of wood in there to make smoke. Should I put the wood on top of the rocks, or how about getting an aluminum pan and set on top of the rocks and put the wood in the pan?

What kind of smoker?

Dont need the pan. The lava rocks are there to help retain heat in the box. Can just put the rocks on top

I think he meant to put the WOOD on top of the rocks. But, you'll have to deal with the ash, and that will insulate the rocks from the meat. a pan will keep it controled.

You can also put soaked wood chips in an aluminum pan over the lava rocks.
I haven't seen a grill with lava rocks in years. They used to be popular for landscaping around here. Some of my neighbors still have them