This image shows an eroded outcrop of a block and ash flow of the Tschicoma Formation in upper Rendija Canyon, Los Alamos, New Mexico, US. The individual blocks within the flow show cooling fractures typical of such flows.
<a href="//commons.wikimedia.org/wiki/User:Kent_G._Budge" title="User:Kent G. Budge">Kent G. Budge</a>
<span class="int-own-work" lang="en">Own work</span>