Large reef complex:
Southern part dominated by microbes and algae, northern part with abundant stromatoporoids.
580 -600 m thick oil field. Top in 2300 m depth.

Izhella, Epiphyton, Issinella, Shuguria, Girvanella, Solenopora and stromatoporoids (Stellepora), bryozoans, corals (Thamnophyllum, Penechiella, Thecostegites, Syringopora).
Additionally forams, brachiopods, pelecypods, crinoids.