best viewed at original size

Bromfield Swamp is a maar – a crater formed when hot larva from below hit the water table, causing an aqueous explosion. This happened possibly as recently as 11,000 years ago and probably well within the period of Aboriginal occupation of the region.
Whereas some maars on the Atherton Tablelands have formed lakes (see the next photo), Bromfield Swamp has an outlet.
This image is a merge of four wide-angle photos.