slgwv's photos with the keyword: 20210918 143256 001

On the north side, looking toward the highest part of the rim to the southeast. Apparently the winds were coming from the southwest during the eruption, because most of the erupted debris ("tephra") piled up to the northeast! Most of the tephra is just sediment that was ejected in the explosion, but it includes some basaltic cinders derived from the magma body. They're the dark particles.