Phosphoria Formation
Quick Summary
The Phosphoria Formation is a significant geological feature in the United States, primarily found in Idaho. It is a type of phosphorite, which is a rock rich in phosphates. These phosphates are often derived from marine invertebrates and vertebrate remains.1
Phosphorites are a crucial source for phosphate fertilizers. The Phosphoria Formation itself contains a high concentration of phosphorus pentoxide, around 34% near the surface. While many sedimentary rocks contain some phosphate, rocks predominantly composed of phosphate, like phosphorites, are less common. Other notable phosphorite deposits in the United States include the Monterey Formation in California.12
Ask Britannica AI about this topic
Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.