APE Cave (lava tube)-Mt. St. Helens

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Roger Weller, geology instructor   


last edited:  10/23/17    number of photos:  31 
photos by Mark Weller (copyrighted 2005)

descending into APE Cave
The APE Cave is a lava tube within the southwest flank of Mt. St. Helens;
it is a national volcanic monument.  The lava tube was created
approximately 2000 years ago as a pahohoe lava drained out of an
encrusted cover.  The lava tube in its entire length is 12,810 feet ling,
making it the largest known lava tube in the USA and one of the longest
lava tubes in the world.
also click here for a student paper on APE Cave

 photos of andesitic basalt from the APE Cave 1  2
photo tour
The following set of 31 photos explores the upper cave, a length of about 1.5 miles.
The hike usually takes about 2.5 hours.

 1. START TOUR  hiking up the trail to the APE Cave
 2.  exit from the upper cave
 3.  trail to the upper end of the upper cave

 4.  a collapsed small lava tube along the trail

 5.  a misty entrance to the upper APEpe Cave

 6.  descending into the upper entrance of the upper APEpe Cave

 7.  inside the upper APEe Cave

 8.  wet walls covered with light-colored fungus

 9.  a large lava ball

10.  looking up at the ceiling of the lava tube

11.  "candy kiss" cross-section of lava tube

12.  small basaltic stalactites on ceiling of lava tube

13.  closer view of small basaltic stalactites

14.  Collapsed roof of lava tube provides a skylight

15.  a crack in the wall of the lava tube

16.  a tall area in the lava tube 

17.  a large, trapped lava ball

18.  a wide passage in the lava tube
19.  a banded lava ball

20.  another lava ball or a fragment from the walls of the lava tube?

21.  The lava tube makes a right turn.

22.  more lava stalactites

23.  strange cross-section

24.  floor of the APEe Cave

25.  walking down the lava tube

26.  the light at the end of the tunnel

27.  another large lava ball

28.  fragments from collapse within the tunnel

29.  approaching exit from upper APEe Cave

30.  climbing up to the surface

31.  back into the light

Photos are copyright free for non-commercial educational uses. 
Just credit photos to Mark Weller/Cochise College.