Zaza Formation

The Zaza Formation is a geological formation located in Buryatia (Russia). It dates to the Lower Cretaceous period. It is Aptian in age and consists of sandstones, siltstones, marls and bituminous shales, deposited in a stratified lake. It is situated on a large granite plateau in the NE of Buryatia.[1] The formation is known for its numerous compression fossils of many varieties of insect found predominantly at the Baissa locality.[2] Insects are found in multiple beds throughout the succession, predomiantly in the finer grained facies, the preservation of insect fossils is variable between beds, with good preservation in marl and poor preservation in shale beds.[1]

Zaza Formation Stratigraphic range: Aptian PreꞒ Ꞓ O S D C P T J K Pg N
Type	Geological formation
Overlies	Paleozoic granite basement
Thickness	Around 80 metres at Baissa
Lithology
Primary	Sandstone, siltstone, marl, and bituminous shale
Other	Conglomerate, limestone
Location
Region	Buryatia
Country	Russia

See also

• List of fossil sites

References

1. Zherikhin, V.V., Mostovski, M.B., Vrsansky, P., Blagoderov, V.A. and Lukashevich, E.D. 1999. The unique Lower Cretaceous locality of Baissa and other contemporaneous insect-bearing sites in North and West Transbaikalia. Proceedings of the First Palaeoentomological Conference, Moscow, 1998. Bratislava: Amba Projects, pp. 185-192.
2. "Baissa (PIN collection 3064, bed 31) (Cretaceous of Russian Federation)". fossilworks.org. Retrieved 2020-01-26.

Further reading

• Vickers-Rich, Patricia; Rich, Thomas Hewett (1993). Wildlife of Gondwana. Reed. ISBN 0-7301-0315-3.