Poleta Formation

The Poleta Formation is a geological unit known for the exceptional fossil preservation in the Indian Springs Lagerstätte, located in eastern California and Nevada.

[3] The formation was deposited on an offshore shelf, and experienced storm-related pulses of siliciclastic sediment input.

[3] The quality of preservation was obtained by the rapid burial of organisms in obrution events, which buried them out of reach of would-be scavengers.

[3] Non-mineralized components of these fossils are also preserved, as are sponges, anomalocaridid parts, and a range of algae and cyanobacteria.

[3] Trace fossils, mainly Planolites, are also common; ichnofossils generally lie on the bedding plane and very few penetrate more than 1 millimetre (0.039 in) into the sediment.