G E O to u rism
California's Death Valley -
A Land of Contrast
Photo: Tom Smith
The extremes in landscape that characterize Death Valley National Park yield striking
landforms, dramatic and colorful scenery­, and underlying geologic mystery.
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Photo: Tom Smith
High above North America’s lowest point, salt pans, enormous alluvial fans, and spectacular geology are
all seen from Dante’s View.
© USGS
t
Mesquite Sand Dunes located in the center of
Death Valley offer tranquility and breathtaking
views of the surrounding mountains. Hikers are
regularly seen traversing these dunes, but caution
is advised due to the hazards of intense heat, sun,
and lack of water.
Located in southeastern California, U.S.A., Death
Valley is easily
reached by driving from major
airports serving
southern California and Nevada.
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Backwater
11049 feet
3368 meters
Sea level
-282 feet
-86 meters
© USGS
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Deborah Bertossa and Thomas N. Smith, Associate Editor
Death Valley National Park encompasses
14,000 km² of deserts and mountains, and
is the largest outside of Alaska. The Park
boasts extremes like no other. Badwater
Basin, at 86 m below sea level, is the
lowest point in the Western Hemisphere
not covered by water. Telescope Peak in
the Panamint Mountains, at 3,368 m in
elevation, lies just 24 km to the west.
This vertical drop from Telescope Peak to
Badwater is twice the depth of the Grand
Canyon and the largest vertical drop in the
contiguous 48 states. Death Valley is the
hottest, with a record temperature 56.67 °C,
and driest place in North America,
receiving less than 50 mm of rainfall per
year.
These factors give the area a forbidding
image, yet for the nature or rock lover, the
area offers extremes in beauty and fascinating geology.
AN
GE
GEOtourism
A cross sectional view of the Basin and Range topography of Death Valley National Park and surrounding areas.
Devil’s Golf Course (foreground) is several feet above flood level. Capillary action draws moisture up
into the salty crystal structures and is quickly evaporated, leaving a field of salt pinnacles. Snow covered
Telescope Peak and alluvial fans are pictured in the background.
Photo: Tom Smith
Death Valley is the youngest and
most active portion of a Basin and
Range province that covers most of
the southwestern United States and
northwestern Mexico. The province is
characterized by the formation of steep
mountain ranges separated by dry, flat
valleys. The northward movement of the
Pacific Plate, at about 25 mm per year, is
pulling on the North American Plate where
Death Valley is situated. This “stretching” of
the earth’s surface is pulling apart the
North American Plate, fracturing the crust
and creating large normal faults and the
“Basin and Range” topography. Most of the
major topographical features seen today
had formed by about 2 million years ago.
The Death Valley area is still tectonically
active as evidenced by the recent fault
scarps in many of the alluvial fans.
Volcanism has also played a part in
Death Valley's recent geologic history.
Extension and thinning of the crust
created zones of weakness, usually along
faults, that allowed magma from deep
within the earth to reach the surface.
Aligned volcanic cones can be seen along
the bases of the mountains on the west
side of the valley. Many areas west of the
park in the nearby eastern Sierra Nevada
are still considered volcanically active.
Photo: Tom Smith
Recent Formation
The giant Ubehebe Crater field (an Indian name meaning "Big Basket in the Rock") attests to the violent
volcanic activity associated with the faulting and stretching of the earth's crust. The eruptions here
occurred anywhere from 3,000 to 10,000 years ago. There are over 12 volcanoes in this complex, with
Ubehebe being the largest and youngest. The crater itself is 234 m deep and approximately 804 m wide.
These explosions stemmed from pressure building up as rising magma mixed with water saturated bedrock. Immense steam explosions created numerous volcanic craters called maars.
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Wind and Water Shape the Land
Photo: Tom Smith
National Park Service
personnel guide geological tours up the
water-polished marble
of Mosaic Canyon. The
marble originated as
limestone laid down
when the Death Valley area was covered
by tropical seas during
the Late Precambrian,
then deeply buried and
metamorphosed into a
"mosaic" of carbonate
rocks and marble.
Photo: Tom Smith
Photo: Tom Smith
Artist's Drive is a oneway, one lane road
leading to views of the
Miocene Artist Drive
Formation. A thick
section of cemented
gravel, playa deposits
and volcanic debris
is exposed above the
road. Chemical weathering and hydrothermal
alteration have transformed these deposits
into the beautiful array
of colors known as Artist's Palate.
The crudely bedded,
chaotic debris of an
alluvial fan exposed at
Natural Bridge.
A stroll along the salt
pan of Badwater will
take you to an expanse
of dry lake bed composed of a salt layer
on top of briny mud
and the lowest place in
North America.
t Photo: Tom Smith
Water became a major factor in shaping
the landscape as we see it today. During the
cooler, wetter conditions of the Pleistocene
ice age (186,000 to 128,000 years ago), large
lakes formed in the valleys from runoff of
the surrounding mountains. This led to
erosion, formation of coalescing alluvial
fans, and consequent lake sedimentation.
Most notable of these lakes is the prehistoric
Lake Manley, once a 180 m deep, 180 km
long lake covering much of Death Valley.
As conditions became warmer and drier,
Lake Manley receded. Shoreline terraces of
the ancient lake can still be seen along the
flanks of the adjacent mountains.
Later, during the Holocene (2,000 to
4,000 years ago), wet conditions again
prevailed and water accumulated in the
valley floor. Combining with minerals left
behind from earlier lake deposits, the water
evaporated leaving a shallow briny lake. A
salt pan is all that remains of these lakes
and now covers more than 518 sq km of
the valley floor.
Water is also responsible for the
numerous alluvial fan formations that can
be seen on all sides of the valley, many with
shallow channels incised on their surface.
Starting high in the mountains, layers of
bedrock are gradually broken into blocks.
Storms create flash floods that bring these
large blocks down the steep mountain
sides, gradually breaking them apart. Most
of the material is deposited in a chaotic
manner in the form of large alluvial fans as
debris filled waters slowed onto the valley
floors.
Death Valley’s recently uplifted mountains
expose Precambrian rocks as old as 1.8 billion
years to recent deposits. These rocks give
evidence of ancient seas, tropical climates,
mountain building, and volcanism and are
as diverse as the present day landforms.
Wind also plays its part in Death Valley.
Smaller particles of silt and sand grains are
picked up by the winds sweeping across
the valley creating interesting deposits
including sand dunes and prime examples
of "desert pavement." The wind working
in two ways, both depositing and eroding,
have helped form these pavements. Desert
pavement consists of tightly packed stones,
coated with "desert varnish." Wind shaped
rocks called ventifacts are also left with
the "desert varnish", or a wind derived
dark coating of clay, iron, and manganese
oxide. Many of the ventifacts display their
sand blasted surfaces as pits, flutes, and
grooves.
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GEOtourism
was covered by warm tropical seas. Other
interesting sites include Salt Creek where
the renowned pupfish have adapted to
their very warm and saline environment.
The National Park Service Headquarters
and Information Center is located at
Furnace Creek, a true oasis in the desert.
Here underground freshwater springs
The racetrack
Another example of the power of wind in Death Valley is at the
Racetrack in the northwest corner of the Park accessed by a 43 km
long rough road that traverses several large alluvial fans before
reaching the playa. Here rocks ranging from cobble to
boulder size mysteriously scoot along the
lakebed (playa), although there is no
record that a human has ever seen
this in action.
Rocks falling from the surrounding mountains begin their journey on the
playa. Scientists have long speculated on the cause of
these wandering rocks with the best explanation being that rocks will
sail across the playa only when the conditions are just right. The few
times during the year that the playa receives water, the Racetrack will
flood and the fine-grained, slippery clay settles. Wind, which is the
accepted motivating force, can reach over 144 km per hour, will actually break the rocks free from their bond with the mud and literally
sail them, some up to a few miles per hour, across the lakebed.
One study conducted during the winter of 1992-93 concluded that these stones are riding on a large sheet
of wind-driven ice. Other studies show that the
trails left on the mud floor are not compatible
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Photo: Tom Smith
Death Valley is truly a land of extremes.
From high temperatures, low rain fall,
towering mountains and expanses of salt,
everywhere you look the contrasts are
unmistakable. Winter can bring snow and
fierce winds; springtime can bring colorful
wildflowers that cover the hills; summer
soearing temperatures; and fall as a time
to reflect on this dramatic landscape.
Early explorers tried to find riches
hidden in the surrounding hills. Borax was
mined here and prospectors, like Walter
Scott (Death Valley Scotty), exploited the
mysteries of Death Valley to raise money
to build his “castle”. Tours of the Spanish
styled Scotty's Castle, built in the late
1920's and containing priceless antiques
and art objects, are conducted year round.
There are many hikes and drives
available that take you through deepsided slot canyons of colorful limestones
that were laid down millions of years ago
when the area now known as Death Valley
In 1881, borax was discovered in
the Death Valley playa near what
is now the Furnace Creek area.
At that time borax was in high
demand for use as an antiseptic,
washing agent, and welding flux. A
commercial borax mine operation,
Harmony Borax Works, flourished
as mule teams were used to haul
the borax to market. Nearby underground springs made living in this
harsh desert possible and the town
of Greenland was built (later called
Furnace Creek). Death Valley was
"put on the map" and in 1933 was
declared a National Monument,
and in 1994 gained National Park
status.
permit living in this intense climate
with shady trees, visitor information and
accommodations, a large swimming
pool, and an 18-hole golf course where
sightings of roadrunners and coyotes are
not uncommon. More information on the
Park and its vast areas to explore can be
seen on the web at www.nps.gov/deva.
Photo: Tom Smith
So Much More...
with ice transport, therefore, there is no positive explanation as to
exactly how wind can move these rocks.
The stones can move by rolling or sliding. Many take a somewhat
linear path while others will divert in various different directions and
often cross each other. Some tracks have been measured as long as
595 m and will remain on the playa for about 3 or 4 years. Many
rocks will not move for several years, then disappear. One
very large rock researchers labeled “Karen”, weighing 317
kg, remained at the end of 173 m track and did not move
over a 7-year study period. Karen later vanished after an
intense winter during 1992-93, only to be located again the
following year 0.8 km away with no visible tracks.
Visitors are welcome to walk out on the playa to observe
the stones and their tracks only when the playa is dry, however,
removing or disturbing them is not permitted. No one can fail to be
awed by these mysterious rocks and their mud trails.
Rocks mysteriously change directions and cross paths on Racetrack Playa.