From this location one can observe many features left behind by
the great Ice-Age floods. These cataclysmic events shaped the
Pacific Northwest as recently as 13,000 years ago. For more
information on these floods visit: www.iceagefloodsinstitute.org.
Cache Elevation = 1950 ft
General Directions: Between MP 60-61 on SR 24 turn north
onto side road that heads straight for the crest of the Saddle
Mountains. Road gains ridge after 4 miles. Turn right (east)
following the ridgecrest for 1.2 miles to the end of the road and
park near the concrete pads for an abandoned Nike missile site.
Saddle Mountains Overlook
The Saddle Mountains is an upfolded ridge of basalt called an
anticline. This ridge was too high for the Ice-Age floods (coming
from the northeast) to go over, so the floods all raced along the
north side of the ridge, before escaping through openings in the
ridge to the west (Sentinel Gap) and to the east (Othello
Channels).
This location is a terrific place to get an overview of Ice-Age
flood features, including lower Drumheller Channels and Crab Creek
Coulee. The closest and most impressive flood feature from this
location is the Corfu Landslide, the top of which lies immediately
before you.
A massive landslide moved away from this precipice, called the
headscarp of the slide, multiple times during the Ice Age. The
prominent U-shaped notch along the ridgeline just to east of here
marks the head of the Corfu Landslide where it took out a big bite
in the ridgeline (see below).
The hummocky slope below the precipice is all landslide debris,
which very rapidly moved downslope into the Othello Basin under the
force of gravity. The virtual cache is located at the precipice
along the edge of the head scarp - watch your step!
The Corfu Landslide complex, which consists of at least 24
separate landslide events, covers 7 to 8 square miles. Ice-Age
floods that eroded Lower Crab Creek Coulee probably undercut the
steep north-facing slopes of the Saddle Mountains, causing the
mountainside to slump away. Earthquakes that accompanied Ice-Age
floods may have triggered many of the landslides. Even though
floodwaters reached only about half way up the side of the Saddle
Mountains (1200-1300 ft elev.), landslides extended all the way to
crest of the ridge (~2000 ft elev.).
At least some sliding occurred before the last Ice-Age flood.
Geologists have determined this by identifying older landslide
debris that was eroded and smoothed by younger floods. Some
landsliding occurred after the last scabland flood too, however.
This is indicated by several landslide-generated debris flows that
ran into Lower Crab Creek Coulee. Any flood coming down Crab Creek
after these lobes of debris formed would surely have eroded away
this material along the bottom of the coulee.
The surface soil at this site has formed during and since the
last glacial period and is full of a mineral concentrate of calcium
carbonate called caliche. To receive credit for finding this cache
please email bjorn99352@yahoo.com with your answer to the
question: "What color is the soil beneath your feet at the cache
site?"
To experience more incredible features left behind by the
Ice-Age floods try finding these other geocaches placed by
geologist Bruce Bjornstad:
Staircase Rapids
Upper Goose Lake
Frenchman Coulee Rib
Rattlesnake Slope Erratics
Devils Canyon
Wallula Gap Overlook
Potholes Coulee
West Bar Overlook
Lake Sacajawea Flood Bar