Usili Formation
Geology
Group: Songea
Members: unnamed (12)
Lithologies: not reported (9), mudstone (2), sandstone (1), conglomerate (1)
Paleoenvironments: terrestrial indet. (11), fluvial-lacustrine indet. (1)
Age range: Wuchiapingian or 259.51000 to 254.14000 Ma