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USGS scientist collects a sample from a basalt lava flow for cosmogenic surface exposure dating

Detailed Description

A USGS scientists uses a hammer and chisel to collect a sample from the surface of a basalt boulder in the San Francisco Volcanic Field of northern Arizona.  The age of the sample will be determined using a technique called cosmogenic surface exposure dating, which determines how long the rock has been exposed to cosmic rays at the surface of the Earth.  USGS photo by Kellie Wall, October 4, 2022.

Sources/Usage

Public Domain.

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