Geology Field Trips
Geology Home Page
Geology Tours of
Roger Weller, geology
number of photos: 31
photos by Mark Weller
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
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
tubes in the world.
also click here for a student paper on APE Cave
of andesitic basalt from the APE Cave:
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.
START TOUR hiking up the trail to the APE Cave
exit from the upper cave
trail to the upper end of the upper cave
a collapsed small lava tube along the trail
a misty entrance to the upper APEpe Cave
descending into the upper entrance of the upper APEpe Cave
inside the upper APEe Cave
wet walls covered with light-colored fungus
a large lava ball
looking up at the ceiling of the lava tube
"candy kiss" cross-section of lava tube
small basaltic stalactites on ceiling of lava tube
closer view of small basaltic stalactites
Collapsed roof of lava tube provides a skylight
a crack in the wall of the lava tube
a tall area in the lava tube
a large, trapped lava ball
a wide passage in the lava tube
a banded lava ball
another lava ball or a fragment from the walls of the lava tube?
The lava tube makes a right turn.
more lava stalactites
floor of the APEe Cave
walking down the lava tube
the light at the end of the tunnel
another large lava ball
fragments from collapse within the tunnel
approaching exit from upper APEe Cave
climbing up to the surface
back into the light
Photos are copyright free for non-commercial educational uses.
Just credit photos to Mark Weller/Cochise College.