slgwv's photos with the keyword: mold

Another example in the Lava Cast Forest, outside Bend, Oregon. For detailed description see the adjacent photo or the album.

In the Lava Cast Forest, Deschutes National Forest, outside Bend, Oregon. A young (ca. 8000 years BP) basalt flow from Newberry Volcano engulfed a forest, and many of the trunks left hollow casts. The lava would chill and harden around the tree, and then the wood would burn out to leave a mold, as here.