Crater Lake Institute
 

 Home | Site Map | About Us | Donate/Join Us | Contact Us | CLI Store | Press Room

 
 
 You are here: Home > Natural History > Geology > Prominent Geological Features > Llao Rock

Llao Rock - Prominent Geological Features of Crater Lake National Park

 
This great mass of dacite (a sluggish lava) was produced from a vent on the upper slopes of Mazama and hardened after moving only a mile or two. The dacite filled in a former explosion crater. This rock rises nearly 2,000 feet above the water- -the highest vertical precipice on the rim- -and was formed by the most massive single flow apparent in the caldera wall, with a maximum thickness of 1,200 feet.

Llao Rock, Crater Lake National Park, photo by Robert Mutch

Note: the numbers associated with each feature name above correspond to their place on the Custom Google Map below

  Related Materials

 

Crater Lake National Park

Prominent Geological Features Map


View Larger Map

 

 

 Site Navigation

  Arts

  Crater Lake News

  Cultural History

  Natural History

     Animals

     Climate

     Ecology

     Fungi

     Geology

        Features

        Field Trips

        Geologic History

        Petrology

        Processes

        Soils

     Nature Notes

     Night Sky

     Plants

  Online Library

  Planning a Visit

  Research

 

Current Conditions at Crater Lake National Park

(Image by Grovin Thewer)

 

Crater Lake Webcam