National Park Service U.S. Department of the Interior Cinder Cones, Lava Flows, and Lava Tube Mojave National Preserve Driving across the Mojave Desert on Interstate 15 or Kelbaker Road, visitors might notice a series of peculiar features on the horizon: thirty-two conical mounds of red and black volcanic rocks rise abruptly above the desert landscape. Surrounded by a sea of hardened lava flows, these little volcanos—cinder cones—began erupting into existence 7.6 million years ago. Lava last flowed just 10,000 years ago. Abundant and well preserved, these geo- logic features were designated as Cinder Cone National Natural Landmark in 1973. Introduction Soda from a Cinder Cone Millions of years ago, fountains of liquid magma erupted through vents in the earth’s crust beneath present-day Mojave National Preserve. Much like the opening of a shaken can of soda pop, hot, pres- surized magma spewed skyward. Upon contact with cool air, the magma instantly solidified, preserving the bubbles created by escaping gases. The light, hole-filled rocks, or cinders, accumulated around the vent and formed a cone-shaped hill. When the grow- ing piles of cinders became too steep, avalanches created the roughly 30-degree slopes evident today. Unlike a can of soda pop, which erupts for only a brief moment, the fountains that create cinder cones can last months, or even years. As subterranean pres- sures decrease and the eruption comes to an end, black basaltic lava may slowly flow from the vent, oozing out across the landscape. Today, basalt formed from such lava flows can be seen among the cinder cones. Most flows are 10 to 13 feet thick, and exhibit both ropy (pahoehoe) and blocky (aa) surfaces. Recipe for a Volcano Volcanic eruptions don’t occur everywhere. Several “ingredients” must combine at the right place and time. While the geologic complexities of Southern California are still under investigation, many re- searchers think that faulting, block movement, and associated magma production are key ingredients contributing to the recipe for cinder cones and lava flows in Mojave National Preserve. During the Mesozoic Era (~245-65 million years ago), extensive tectonic activity in western North America resulted in a dynamic period of volcanism and fault- ing as the Pacific Plate began to slide beneath the North American Plate. Then, around 30 million years ago, great fault systems developed further throughout present-day California. Regional movement of these faults cracked the earth’s crust into blocks. As the plates and blocks of the earth’s crust slide and rotate, they generate friction and tremendous heat. Beneath the Mojave, rocks of the lower crust melted. Because it is less dense than the surrounding rock, the melted, mantle-derived basalt, or magma, rises toward the surface. When magma cannot find a path upwards it pools into magma chambers. These chambers can be huge, providing enough magma for many volcanos over several years. To form a volcano, however, magma must reach the surface. The spaces between fault blocks are zones of weak- ness reaching down to the mantle. Pressure within magma chambers was released as eruptions through such fractures or vents in the earth’s crust, providing magma with a way up and out. With this final ingre- dient, a hot and “fresh” volcano is formed. Flows, Tunnels, & Tubes Not all lava is the same. Very thick, gooey rhyolitic lava doesn’t flow very far. The runny basaltic sort that characterizes some of the lava flows of Mojave National Preserve, however, spreads out as smoothly as hot maple syrup. It flowed from the sides of the cones or pooled near their bases. As the lava streamed out across the land, it slowly be- gan to cool. Often, the top of a flow would cool while liquid lava continued moving underneath, creating a tunnel. When the eruption ended, the flowing lava in the tunnel either cooled in place or emptied out the tunnel’s end, leaving a hollow lava tube. A lava tube is accessible via a 5-mile drive from Kel- baker Road. Climbing through a collapsed hole in the tube’s roof, visitors have a rare opportunity to view this river of rock from the lava’s perspective.
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National Park ServiceU.S. Department of the Interior
Cinder Cones, Lava Flows, and Lava Tube
Mojave National Preserve
Driving across the Mojave Desert on Interstate 15 or Kelbaker Road, visitors might notice a series of peculiar features on the horizon: thirty-two conical mounds of red and black volcanic rocks rise abruptly above the desert landscape. Surrounded by a sea of hardened lava flows, these little volcanos—cinder cones—began erupting into existence 7.6 million years ago. Lava last flowed just 10,000 years ago. Abundant and well preserved, these geo-logic features were designated as Cinder Cone National Natural Landmark in 1973.
Introduction
Soda from a Cinder Cone Millions of years ago, fountains of liquid magma erupted through vents in the earth’s crust beneath present-day Mojave National Preserve. Much like the opening of a shaken can of soda pop, hot, pres-surized magma spewed skyward. Upon contact with cool air, the magma instantly solidified, preserving the bubbles created by escaping gases. The light, hole-filled rocks, or cinders, accumulated around the vent and formed a cone-shaped hill. When the grow-ing piles of cinders became too steep, avalanches created the roughly 30-degree slopes evident today.
Unlike a can of soda pop, which erupts for only a brief moment, the fountains that create cinder cones can last months, or even years. As subterranean pres-sures decrease and the eruption comes to an end, black basaltic lava may slowly flow from the vent, oozing out across the landscape.
Today, basalt formed from such lava flows can be seen among the cinder cones. Most flows are 10 to 13 feet thick, and exhibit both ropy (pahoehoe) and blocky (aa) surfaces.
Recipe for a Volcano Volcanic eruptions don’t occur everywhere. Several “ingredients” must combine at the right place and time. While the geologic complexities of Southern California are still under investigation, many re-searchers think that faulting, block movement, and associated magma production are key ingredients contributing to the recipe for cinder cones and lava flows in Mojave National Preserve.
During the Mesozoic Era (~245-65 million years ago), extensive tectonic activity in western North America resulted in a dynamic period of volcanism and fault-ing as the Pacific Plate began to slide beneath the North American Plate. Then, around 30 million years ago, great fault systems developed further throughout present-day California. Regional movement of these faults cracked the earth’s crust into blocks.
As the plates and blocks of the earth’s crust slide and rotate, they generate friction and tremendous heat. Beneath the Mojave, rocks of the lower crust melted. Because it is less dense than the surrounding rock, the melted, mantle-derived basalt, or magma, rises toward the surface. When magma cannot find a path upwards it pools into magma chambers. These chambers can be huge, providing enough magma for many volcanos over several years. To form a volcano, however, magma must reach the surface.
The spaces between fault blocks are zones of weak-ness reaching down to the mantle. Pressure within magma chambers was released as eruptions through such fractures or vents in the earth’s crust, providing magma with a way up and out. With this final ingre-dient, a hot and “fresh” volcano is formed.
Flows, Tunnels, & Tubes Not all lava is the same. Very thick, gooey rhyolitic lava doesn’t flow very far. The runny basaltic sort that characterizes some of the lava flows of Mojave National Preserve, however, spreads out as smoothly as hot maple syrup. It flowed from the sides of the cones or pooled near their bases.
As the lava streamed out across the land, it slowly be-gan to cool. Often, the top of a flow would cool while liquid lava continued moving underneath, creating a tunnel. When the eruption ended, the flowing lava in the tunnel either cooled in place or emptied out the tunnel’s end, leaving a hollow lava tube.
A lava tube is accessible via a 5-mile drive from Kel-baker Road. Climbing through a collapsed hole in the tube’s roof, visitors have a rare opportunity to view this river of rock from the lava’s perspective.
Directions to Lava Tube The lava tube is located about 5 miles east of Kelbak-er Road on the unpaved and unsigned Aiken Mine Road. A High clearance vehicle is recommended.
To Aiken Mine Road: From Interstate 15: 19 miles south of Baker, Calif. on Kelbaker Road; turn north (left) onto Aiken Mine Road.
From Interstate 40: 28 miles west of Ludlow, Calif., turn north onto Kel-baker Road; continue 23 miles to Kelso Depot Visitor Center (see below).
From Kelso Depot Visitor Center: 15 miles north of Kelso on Kelbaker Road; turn north (right) onto Aiken Mine Road.
From Jct. of Kelbaker & Aiken Mine Roads: Follow Aiken Mine Road, passing an old water tank and corral after 1.6 miles. At about 4.5 miles, bear left at a fork in the road. Continue another 1/4 miles, past a horse corral to the left, to where the road widens into a circular parking area.
From the parking area, walk uphill on a very rough roadway about 300 yards to a rock cairn (may not be visible) or metal post marking a beaten path toward a cinder cone to the east (right). This trail leads to the lava tube entrance.
The lava tube is not maintained by the National Park Service. Enter at your own risk.
Map
E X P E R I E N C E Y O U R A M E R I C A™
Hiking trail
Cinder cone
Lava flow
Unpaved dirt road
Paved road
Interstate
40
40
40
40
15
15
15
163
127
164
164
95
95
95
Kelso DepotVisitor Center
Hole-in-the-WallInformation Center
Roads may beimpassablein inclementweather
Road notmaintained
M O J A V E
N AT I O N A L
P R E S E R V E
P R E S E R V E
SILVERLAKE(dry)
IVANPAH LAKE (dry)
Ho
mer W
ash
Kelso
Was
h
Cedar Wash
Black Canyon Wash
Watson W
ash
Kingston Wash
Wheaton Wash
Piut
e W
ash
Bull
Sprin
gs Wash
Black
Tank
Wash
KeystoneSpring
RockSpring
HackberrySpring
VontriggerSpring
PiuteSpring
FoshaySpring
QuailSpring
KesslerSpring
WillowSpring
Willow Wash
MOJAVE ROAD
MOJAVE ROAD
MOJAVE
MOJAVE
ROAD
ROAD
UNION PACIFIC RAILROAD
UNION PACIFIC RAILROA
D
BURLINGTO
N NORTH
ERN
SA
NTA
FE
RA
ILW
AY
NEVADA
CALIFORNIA
NEVADA
CALIFORNIA
Cima
Primm
Goffs
Fenner
Essex
Nipton
Ludlow
Searchlight
Cal Nev Ari
PalmGardens
Baker
National
Trails
H
ighway
Mo
un
tain Sp
rings R
d
Essex Road
Blac
k Ca
nyon
Ro
ad
Kelb
aker Ro
ad
Lanfair Road
Zzyzx Road
Kelbaker Rd
Goffs Rd
Cedar Canyon Road
Ivanp
ah Rd
New York Mountains Road
Ivanpah Road
Kelso
Cim
a R
oad
Nipton Road
Cima Road
Mor
ning
S
tar
Min
e R
oad
Wild HorseCanyon Road
Excelsior Mine Road
Goffs R
d
Hart M
ine Road
Aik
en M
ine
Rd
National Trails Highway
Kelbaker Road
Mid Hills to Hole-in-the-Wall Trail
Hole-in-the-Wall Nature TrailRings Trail
KelsoDunesTrailhead
TeutoniaPeak Trail
Hole-in-the-WallCampground
Mid HillsCampground
Black Canyon Groupand EquestrianCampground
21mi34km
18mi 29km
5mi8km
15mi24km
14mi22km
15mi24km
19mi30km
15mi24km
5mi8km
7mi11km
6mi10km
6mi10km
10mi 16km
10mi16km
10mi16km
28mi45km
22mi35km
10mi16km
2mi3km
3mi5km
7mi11km
6mi10km
6mi10km
16mi26km
3mi5km
3mi5km
3mi5km
6mi10km
15mi24km
12mi19km
6mi 10km
26mi42km
5mi8km 14mi
23km
5mi8km
5mi8km
5mi8km
7mi11km
11mi18km
8mi13km
5mi8km
2mi3km
14mi23km
18mi29km
Primm to Las Vegas40 mi64km
Fenner to Needles35mi56km
Searchlight to CottonwoodCove, Lake Mead National
Recreation Area14mi22km
To Laughlin20mi32km
To Amboy18mi29km
To I-4023mi37km
Ludlowto Barstow49mi79km
Searchlight to Las Vegas44mi71km
Baker to Furnace Creek,Death Valley National Park113mi182km