Geology (Unit 2) - Boulder Creek Trail: Florissant Formation

Stratigraphy of the florissant formation

The Boulder Creek Trail provides an opportunity to see some excellent outcrops of the Florissant Formation, as well as a variety of wildlife habitats.

A period of volcanic activity followed the final lake shale deposition. Streams flowing from the west washed large amounts of pumice pebbles into the basin. Sanidine samples taken from various parts of the Florissant Formation (including the ash and pumice intervals in the shales) have been dated with the 40At/39Ar method to around 34.07 million years old.

 
Upper pumice conglomerate along the boulder creek trail
Upper pumice conglomerate along the boulder creek trail.
 
Close up of the upper pumic conglomerate
Close up of the upper pumic conglomerate.

Last updated: February 24, 2015

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Florissant, CO 80816

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