Lateral equivalent ot Baratumu Fm., which is dated Aquitanian to Burdigalian.
But reefs thought to range through whole Miocene.

Mararani and Dodori wells of BP/Shell.
Lamu Reefs encountered in five wells but interpreted shelf margin reef trend is 550 km. 
Reefs enveloped in shale.
Biogenes: Bryozoans, corals, sponges, echinoids, ostracods and crustacean limbs.
