Lake Ouachita Geo-Float Trail guides boaters around Lake Ouachita, highlighting and describing many geological formations unique to the area.
The trail is a 16 mile trip with twelve exploration areas from the Spillway Recreation Area to
Brady Mountain Recreation Area , and will take about 1 1/2 hours to complete depending on your speed and the time you spend at each stop.
Amy Shultz is the Lake Ouachita contact for the Corps and may be reached at 501-767-2101 extension 73075 to schedule program presentations or for
The Geo-Float Trail calls attention to the special beauty of the area and gives visitors an increased understanding of the formation of the Ouachita Mountains.
can get the free Self Guided Float Trip map from the the Spillway or Brady Landing on Lake Ouachita, or the local Corps of Engineers, and you will be
set to follow the yellow marker buoys around Lake Ouachita.
For group tours of 15 or more (must be a bonafide interested group, not a family reunion), when you provide the boat, the Corps of Engineers will provide a ranger to
accompany the trip and explain the lake features.
Lake Ouachita is located 13 miles northwest of Hot Springs, in the heart of the Ouachita Mountains.
"Welcome to Rockhounding Arkansas" by Mike and Darcy Howard, great
information about mineral collecting in Arkansas.
The 12 Stop Geo Tour
Click to enlarge
Named for the whirlpool that existed at its base
when the Ouachita River flowed freely, this cliff is made of
450-million-year-old sandstone turned on edge.
B. Submarine Slide
This conglomeration of boulders,
pebbles, cobblestones and sedimentary rocks is the result of a giant
underwater mudslide created by an ancient earthquake. As the rocks and
stones slid down the continental shelf, they mixed with mud, silt and sand,
and eventually the whole concoction was compressed into stone.
C. Zebra Rock
One of the richest quartz-crystal
districts in the world, the quartz is
known as Arkansas diamonds. Spectacularly displayed at Lake Ouachita's famed Zebra Rock. The
milky-white quartz “gash veins” pop out against the dark sandstone cliff.
D. Recumbent fold
A wavelike pattern of
rock cause by the collision of continental plates in this cliff face. An impressive
type of geologic folding, where the layers of sandstone were compressed and
bent over one another into an S curve.
E. Mountains and valleys
Millions of years of erosion wore away
this region’s softer rock, shale, slate
and limestone, leaving behind the harder substances, such as sandstone, that
lie at the core of those long, thin ridges.
F. Rolling stones
Sandstone boulders that came from the outcrop up the hill, the
mystery is what brought them down here to this shale beach. There are two
leading suspects: The constant freezing and thawing of the last ice age
could have broken them free, or perhaps it was one of the many major flash
floods from a period of time when Arkansas was much drier.
G. Geologic fish shelter
Though this group of boulders is not as
prominent a geologic feature as others on the map, it’s worth a stop on your
next fishing trip because the large cracks between the boulders provide
excellent shelter for bait fish, which hasn’t gone unnoticed by their
H. Checkerboard Point
One look, and the name makes sense. And
though this pattern of cubelike stones almost seems unnatural it is the result of sandstone bent to its breaking point when these
mountains were formed.
The newest geologic formation on the lake, these
miniature caves can be found all over Lake Ouachita and are the result of the
lake’s waves wearing away at the soft lime that cemented the rocks
J. Mother Nature’s beach
These natural beaches on the
particles under your feet are
Granulated Bigfork Chert
a rock famous in
these parts for being one of the best aquifers around.
K. Folds and faults
Lake Ouachita is located at the heart of the
Ouachita Mountains, where the greatest deformation occurred when the
mountains were formed. As a reminder of just how geologically complex the
region is, this stop features a recumbent fold topped by a wavelike fault.
L. Sticks and stones
The last stop along the trail is all about
the subtle ways geology shapes the world around us. Looking up at this
ridge, you’ll notice pines to your left and eastern red cedar to your right.
That’s because the soil in which the pines grows is made of sandstone, while
the cedars grow on soil made from shale and slate - a poor soil in which only
the cedar tree can thrive.