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Mojave National Preserve U.S National Park Service Mojave National Preserve U.S. Department of the Interior Cinder Cones, Lava Flows, and Lava Tube Introduction 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. Recipe for a Volcano Volcanic eruptions don’t occur everywhere. Several As the plates and blocks of the earth’s crust slide “ingredients” must combine at the right place and and rotate, they generate friction and tremendous time. While the geologic complexities of Southern heat. Beneath the Mojave, rocks of the lower crust California are still under investigation, many re- melted. Because it is less dense than the surrounding searchers think that faulting, block movement, and rock, the melted, mantle-derived basalt, or magma, associated magma production are key ingredients rises toward the surface. When magma cannot find a contributing to the recipe for cinder cones and lava path upwards it pools into magma chambers. These flows in Mojave National Preserve. chambers can be huge, providing enough magma for many volcanos over several years. To form a volcano, During the Mesozoic Era (~245-65 million years ago), however, magma must reach the surface. extensive tectonic activity in western North America resulted in a dynamic period of volcanism and fault- The spaces between fault blocks are zones of weak- ing as the Pacific Plate began to slide beneath the ness reaching down to the mantle. Pressure within North American Plate. Then, around 30 million years magma chambers was released as eruptions through ago, great fault systems developed further throughout such fractures or vents in the earth’s crust, providing present-day California. Regional movement of these magma with a way up and out. With this final ingre- faults cracked the earth’s crust into blocks. dient, a hot and “fresh” volcano is formed. Soda from a Cinder Cone Millions of years ago, fountains of liquid magma Unlike a can of soda pop, which erupts for only a erupted through vents in the earth’s crust beneath brief moment, the fountains that create cinder cones present-day Mojave National Preserve. Much like can last months, or even years. As subterranean pres- the opening of a shaken can of soda pop, hot, pres- sures decrease and the eruption comes to an end, surized magma spewed skyward. Upon contact with black basaltic lava may slowly flow from the vent, cool air, the magma instantly solidified, preserving oozing out across the landscape. the bubbles created by escaping gases. The light, hole-filled rocks, or cinders, accumulated around the Today, basalt formed from such lava flows can be vent and formed a cone-shaped hill. When the grow- seen among the cinder cones. Most flows are 10 to ing piles of cinders became too steep, avalanches 13 feet thick, and exhibit both ropy (pahoehoe) and created the roughly 30-degree slopes evident today. blocky (aa) surfaces. 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. Primm to Las Vegas Searchlight to Las Vegas G E 40 mi 44mi H N 64km S 71km A E I R N G K G ing I sto Primm N H n A W N A a I T Nearby Desert National Park System Areas sh R L A A T N H N 0 km 50 E N U x G D c U O 267 e U UTAH R 0 mi 50 93 l O M s NEVADA O i CALIFORNIA A o L NEVADA M 5mi Y r N Death L 395 8km A M G 15 U 95 R Valley i E K C 373 n 190 Shadow G NP do e R c ra Mountain Y lo R R Las o iv 4197ft A M C e o U C Vegas r N 1279m a L IO U d MOJAVE 95 Lake C N L Primm Mead P 127 S Yates Well A 14 NRA NATIONAL C Clark Mountain IF 95 7929ft IC C 93 H 3mi 21mi Mojave o 2417m IVANPAH R l Kingman PRESERVE A 5 58 Barstow o 40 5km I 34km National r L a 15 LAKE R 395 Preserve d Flagstaff A O o 40 (dry) A Searchlight to Cottonwood 14 D Needles R ARIZONA Cove, Lake Mead National D 5mi iv CALIFOR NIA e 8km Recreation Area 95 r 14mi 62 164 Los Angeles O 22km The lava tube is located17 about 5 miles east of Kelbak- From Jct. of Kelbaker & Aiken Mine Roads: L ash Directions to Lava TubeJoshua HIL W K n Tree NP 177 5mi HAW o 15 MO 14mi Mountain Pass at Searchlight er Road on the unpaved and unsigned Aiken Mine Follow Aiken MineW 8km Road, passing an old water tank he 10 23km 4730 ft W Nipton 1742m 3mi 5 Salton Road. A High clearancePhoenix vehicle is recommended. and corral after 1.6 miles. At about 4.5 miles, bear left P Sea 5km 7mi Nipton Road 11km I at a fork in the road. Continue another 1/4 miles, past 164 U Airstrip M I T To Aiken Mine Road: a horse corral to the left, to where the road widens E N Baker to Furnace Creek, G E E R Death Valley National Park N From Interstate 15: into a circular parking area. A A 113mi L 3mi Y sh R 182km a 5km V 19 miles south of Baker, Calif. on Kelbakers W Road; turn L H A I E ng C L ri ES L A north (left) onto AikenTurquoise Mine Road.Sp HalloranFrom Summit the parking area, walk uphill on a very rough M Kokoweef L S L 127 Mountain ll Solomons 4000ft 4511ft u Knob Peak B 1219m C Ivanpah Road L 1375m roadway about 300 yards to a rock cairni (may not be 6038ft L m 1840m N a E From Interstate 40: visible) or metal post markingV a beaten pathR toward a A I o Y a 26mi A d V 28 miles west of Ludlow, Calif., turn north onto Kel- cinder cone to the east (right). This trail leads to the Striped S A 42km Mountain L T d T baker Road; continue 23 miles to Kelso Depot Visitor lava tube entrance. 12mi 5929ft a L 19km 1807m o MorningM R N Castle Center (see below).Halloran Springs 6mi Peaks E Star Mine e 10km in 5829ft The lava tube is not maintained by the National H U 1777m Y M A r a O From Kelso Depot Visitor Center: Park Service. Enter at your own risk. t H W 18mi h P S il ash s low W Hart a 15 miles north of Kelso on Kelbaker Road; turn north 15mi A Willow 29km M Peak W SILVER S N g 24km Spring n 5543ft LAKE i P N e 1689m t (right) onto Aiken Mine Road. A n I r u (dry) Kessler i 15 o N A P Peak V M T 6163ft I A N 1878m V Airstrip Map Teutonia I U Cal Nev Ari Peak Trail O Ro M Teutonia Kessler e ad Peak K n E Spring i 5755ft 15mi M L 1754m R t 24km ar T O H S A 6mi C YA C 10km R Keystone P W U Spring Baker 7533ft T h H s I Kelbaker a E 2296m E Rd W R U k N S n a C T A k T Wildcat Butte N 19mi ac l Y B 5179ft 30km O 1579m E Cima N NEVADA CALIFORNIA CINDER CONE LAVA TUBE ew York 15 N Mou nta R ins Ro NATIONAL NATURAL 5mi ad Palm d 8km PINTO A Gardens R VALLEY LANDMARK e n N i S 163 M I Water Tank L v Z n a G n To Laughlin z e & Corral L LANFAIR y k M Pinto p z i I O 5mi 20mi x Mountain a E A 6mi JA V 6144ft 8km h 32km R 10km E VALLEY o H 1873m R a D GROTTO d d A D 95 RO ROA HILLS VE sh 3mi Lanfair Buttes MOJA a Government Rock 4360ft W Mid Hills 5km Spring MOJAVE 1329m o Holes R ls h Campground OA e Was 15mi D K dar 2mi Ce ROUND Cedar Canyon Road Zzyzx 3km 24km Fort Piute Desert Studies Center VALLEY D (site) MOJAVE ROAD I Roads may be impassable Piute in inclement M Table Top Spring North 15mi weather 24km 14mi Wild Horse 6176ft LAVA TUBE 22km Canyon Road 1882m 7mi K e Mid Hills to Hole- 11km l M b GOLD P A in-the-Wall Trail R 18mi a C ED W E C k O VALLEY O G I 29km e N O G in IA 10mi Hackberry I U r D R CA N S T S d NYO 16km Spring ON LL Lava Tube Trail R I e V H T r o Black Canyon Group a d M Vontrigger E C d a and Equestrian O Hackberry Spring o o n R Campground U Mountain e N 5390ft a Hole-in-the-Wall T A 1643m im Hole-in- Homer Mountain C Campground Tortoise Shell I 3739ft the-Wall Mountain N S 1140m so l S Fire Center 4610ft e 1405m F K V E Signal Hill N Hole-in-the-Wall W N L 3602ft a A Kelso Depot a 1098m I 16mi n Information Center t N s f o 26km L Visitor Center E a 300yds A n i r Hole-in-the-Wall Nature Trail R B W L T la R c Rings Trail k a o d V E C s a D a h A N a A d O o n R Y Rough Roadway RAIL y C R o L FI n I U C L A PROVIDENCE n P W NION o 10mi E U y a O MOUNTAINS STATE 16km s Y n h RECREATION AREA a C M Mary Beal Nature Trail k Fountain Peak c va F 6996ft a La low Lava Flow l 95 2132m B Rd offs 6mi G 10km PRESERVE 14mi 23km Goffs Schoolhouse Vulcan Foshay 5mi Mine Spring Goffs 8km S E M N Y U Goffs o Fenner to Needles D To I-40 E u Historic Route 66 passed E E Butte O n 35mi S 23mi s 3612ft through this area along L t C s E L e 1101m a 56km K 37km S x i S various alignments.
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