Lava River Cave
Encyclopedia
The Lava River Cave near Bend, Oregon
, is part of the Newberry National Volcanic Monument
, which is managed by the United States Forest Service
. The cave is an excellent example of a lava tube
. At 5,211 feet (1,588 m) in length, the northwest section of the cave is the longest continuous lava tube in Oregon
. While the cave’s discovery in 1889 was officially credited to a pioneer hunter, the presence of obsidian
flakes near the cave has led archaeologists to conclude that Native Americans
knew about the cave long before settlers arrived in central Oregon.
The cave is located at .
. However, the specific vent that created the cave has been buried by several younger flows.
The Lava River Cave was created by lava flowing downhill from a volcanic vent. The lava flowed northwest from the vent toward the Deschutes River. The flow began as a river of lava flowing in an open channel. Eventually, a lava crust solidified over the top of the flowing lava. This formed a roof over the river, enclosing it in a lava tunnel or tube. When the eruption from the vent stopped, the lava drained out of the tube leaving a lava tube cave behind. After the cave cooled, a section of the its roof collapsed. This collapsed section provided the entrance to both the uphill (southeast) and downhill (northwest) cave sections.
The area around the Lava River Cave receives about 18 inches (457 millimeter) of precipitation per year. Over the centuries, water from rainfall and snow melt has seeped down through the soil and cracks in the cave roof depositing sand on the cave floor. Small rivulets of water carry the sand downhill, plugging the far end of the cave with sediment. As a result, no one knows how far the cave actually extends beyond the sand plug.
The Lava River Cave is located 12 miles (19 kilometer) south of Bend on the east side of Highway 97
. It is part of the Newberry National Volcanic Monument, which is managed by the Forest Service as part of the Deschutes National Forest
.
The forest surrounding the cave entrance is dominated by large ponderosa pine
trees with sagebrush
, manzanita
, bitterbrush, snowbrush
, and chokecherries as the main ground cover. Along the short path leading from the forest floor down to the cave entrance, visitor will also find serviceberry
, False Solomon Seal, squaw currant
, Oregon grape, and small willow
trees.
Animals common in the forest around the cave include Golden-mantled Ground Squirrel
s, chipmunk
s, western gray squirrel
s, porcupine
s, weasel
s, pine marten
s, and mule deer
. In 1991, park personnel observed a full-grown cougar ran out of the cave entrance area, but that was a single sighting. There is also a wide range of resident and migratory bird species common to the area. Small resident birds include wren
s, robin
s, junco
s, thrush
es, woodpecker
s, sapsucker
s, red-shafted flickers, and ruby-crowned kinglets. Larger birds include great horned owl
s, red-tailed hawk
s, vulture
s, and a few golden eagle
s.
Forest Service biologists have identified several species of spiders, worm
s, centipedes, and millipede
s that live inside the cave. There are also mice
and bat
s that live in the cave year around. The cave's bat population is relatively small and the bats are very shy so visitors rarely see them. In fact, bats usually remain in hibernation
until July, and when active they are nocturnal so they are asleep during the day when the cave is open. If a bat is sighted, the Forest Service recommended that it be left undisturbed. Waking it from hibernation is extremely stressful, and can cause the bat to die from the sudden expenditure of energy.
. The first recorded discovery is credited to a local settler named Leander Dillman, who found the cave opening on a hunting trip in 1889. Legend has it that Dillman found the cave entrance while following a wounded deer. After its discovery, he used the cave to cool his venison. The cave acquired its name from a 1923 geology study published by Ira A. Williams. The study also provided the first map of the cave.
In 1926, the Shevlin-Hixon Lumber Company donated the 22.5 acres (91,054.4 m²) site around the cave entrance to the State of Oregon for a park. In 1981, the cave and above ground park area were acquired by the Forest Service as part of a land exchange with the State government. In November 1990, the cave was incorporated into the Newberry National Volcanic Monument. However, it is still managed by the Forest Service along with the rest of the Newberry monument area.
Lava River Cave runs in two directions from the entrance cleft. The main section runs gradually downhill 5,211 feet (1,588 m) in a northwesterly direction from the entrance, passing under Highway 97. This section of the cave is the longest known uncollapsed lava tube in Oregon. The other section extends 1,560 feet (476 m) southeast from the entrance. This section runs toward the source of the flow so it has a slight uphill grade. This section is not open to the public because of loose rocks in the ceiling. The mouth of the cave is at an elevation of 4,500 feet (1,372 m) above sea level. At its deepest point the cave is 4,350 feet (1,326 m) above sea level.
The cave's entrance appears as a large hole in the ground. At its mouth, the entrance trail drops suddenly over a jumble of volcanic rocks. This area is known as the Collapsed Corridor. It is the result of ground water freezing in rock cracks in the ceiling. Loosened rocks eventually fall. Over the centuries, the fallen rocks have accumlated into a large boulder pile. Since freezing temperatures occurs only near the mouth of the cave, most rock-falls are in this area. To get down the rock pile, visitor must descend 126 steps with guard rails for safety. At the bottom of the stairs is a large cool chamber where winter ice fills cracks in the floor and ice stalactites often cling to the ceiling until June.
After a short walk, the ceiling reaches a height of 58 feet (18 m). At this point, the width of the cave is 50 feet (15 m). This massive volcanic archway is called Echo Hall. The smooth walls are remarkably symmetrical so sounds echo in the huge chamber. In this section, remnants of the ancient lava flow’s current can be seen molded in the tunnel walls. They appear as rounded over-hanging shelves and lateral markings etched in the walls. The end of this hall is about 1,500 feet (457 m) into the cave. At that point, the cave passes under Highway 97. The underground crossing is marked by a small sign post.
Beyond the Highway 97 marker, visitors enter an area called Low Bridge Lane. In this area, the ceiling drops to less than six feet (1.8 m). This section of the cave was created after most of the molten lava had drained out of the cave leaving hot gases trapped in the interior of the tube. These gases re-heated the lava tube causing the tunnel walls to re-melt. As re-melted rocks cooled, the walls were left with a shiny, glazed surface. There are also volcanic stalactites in this area of the cave. These formations are sometimes called lavacicles. They are found in two forms. Some are hollow cylindrically shaped soda straws, formed by escaping gases. The others are cone shaped drip pendants formed when re-melted lava dripped from the ceiling. At the end of Low Bridge area, the tube begins to narrow and the cave is divided into two tunnels with intermittent connecting passages. This is the Two Tube Tunnel section of the cave. Both tubes were probably active lava channel
s at the same time; however, the upper channel eventually drained into the lower tube as the flow subsided.
One of the most unique parts of the cave is the Sand Garden, located about 3,000 feet (914 m) from the entrance. Here the floor of the cave is covered with sand. The sand was carried into the cave by dripping water. The sand is fine volcanic ash from the eruption of Mount Mazama
6,600 years ago. Rain and melting snow carried the ash down from the surface through cracks in the rock and deposited it on the floor of the cave one grain at a time. Occasionally, enough water leaks into the cave to create a pool. This allows the sand to spread out across the floor. At the Sand Garden, the constant dripping of water has carved spires and pinnacles in the sand. Since it takes hundreds of years to build these delicate sand forms, the Forest Service has fenced off the garden area to protect it. The 2,211 feet (674 m) of cave trail beyond the Sand Garden has a sandy floor. Along the way, the ceiling descends lower and lower until the sand fills the cave. The last 310 feet (95 m) of the cave was dug out of the sand plug by two men in the 1930s. Exploring this section of the cave requires visitors to crawl on hands and knees for much of the distance to the cave’s end, and usually takes at least thirty minutes.
The air temperature at the mouth of the cave ranges from about 32 degrees to around 45 degrees Fahrenheit (-1 degrees to around 7 degrees Celsius) depending on the time of year. Inside the cave, it is a constant 42 degrees (5.6 degrees Celsius). As a result, the Forest Service strongly recommends that visitors wear a warm jacket while exploring the cave. Lanterns can be rented at the visitor center above the cave entrance. Personal lanterns are also permitted; however, in order to protect the cave’s fragile environment, they cannot have glass globes or use kerosene or white gas. Battery powered lights are best, but they must provide reliable illumination for at least one hour.
Bend, Oregon
Bend is a city in and the county seat of Deschutes County, Oregon, United States, and the principal city of the Bend, Oregon Metropolitan Statistical Area. Bend is Central Oregon's largest city, and, despite its modest size, is the de facto metropolis of the region, owing to the low population...
, is part of the Newberry National Volcanic Monument
Newberry National Volcanic Monument
Newberry National Volcanic Monument was designated on November 5, 1990, to protect the area around the Newberry Volcano in the United States. It was created within the boundaries of the Deschutes National Forest and is managed by the U.S. Forest Service...
, which is managed by the United States Forest Service
United States Forest Service
The United States Forest Service is an agency of the United States Department of Agriculture that administers the nation's 155 national forests and 20 national grasslands, which encompass...
. The cave is an excellent example of a lava tube
Lava tube
Lava tubes are natural conduits through which lava travels beneath the surface of a lava flow, expelled by a volcano during an eruption. They can be actively draining lava from a source, or can be extinct, meaning the lava flow has ceased and the rock has cooled and left a long, cave-like...
. At 5,211 feet (1,588 m) in length, the northwest section of the cave is the longest continuous lava tube in Oregon
Oregon
Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...
. While the cave’s discovery in 1889 was officially credited to a pioneer hunter, the presence of obsidian
Obsidian
Obsidian is a naturally occurring volcanic glass formed as an extrusive igneous rock.It is produced when felsic lava extruded from a volcano cools rapidly with minimum crystal growth...
flakes near the cave has led archaeologists to conclude that Native Americans
Native Americans in the United States
Native Americans in the United States are the indigenous peoples in North America within the boundaries of the present-day continental United States, parts of Alaska, and the island state of Hawaii. They are composed of numerous, distinct tribes, states, and ethnic groups, many of which survive as...
knew about the cave long before settlers arrived in central Oregon.
The cave is located at .
Geology
The eruption which formed this Lava River Cave occurred about 80,000 years ago. The source is believed to be near Mokst Butte southeast of the entrance. The same volcanic flow that formed the cave underlies much of the Bend area and almost reaches Redmond, OregonRedmond, Oregon
Redmond is a city in Deschutes County, Oregon, United States. Incorporated on July 6, 1910, the city is located on the eastern side of Oregon's Cascade Range, in the High Desert, and is considered the geographical heart of Central Oregon...
. However, the specific vent that created the cave has been buried by several younger flows.
The Lava River Cave was created by lava flowing downhill from a volcanic vent. The lava flowed northwest from the vent toward the Deschutes River. The flow began as a river of lava flowing in an open channel. Eventually, a lava crust solidified over the top of the flowing lava. This formed a roof over the river, enclosing it in a lava tunnel or tube. When the eruption from the vent stopped, the lava drained out of the tube leaving a lava tube cave behind. After the cave cooled, a section of the its roof collapsed. This collapsed section provided the entrance to both the uphill (southeast) and downhill (northwest) cave sections.
The area around the Lava River Cave receives about 18 inches (457 millimeter) of precipitation per year. Over the centuries, water from rainfall and snow melt has seeped down through the soil and cracks in the cave roof depositing sand on the cave floor. Small rivulets of water carry the sand downhill, plugging the far end of the cave with sediment. As a result, no one knows how far the cave actually extends beyond the sand plug.
Environment
U.S. Route 97
U.S. Route 97 is a major north–south United States highway in the western United States. It begins at a junction with Interstate 5 at Weed, California, and travels north, ending in Okanogan County, Washington, at the Canadian Border, across from Osoyoos, British Columbia, becoming British...
. It is part of the Newberry National Volcanic Monument, which is managed by the Forest Service as part of the Deschutes National Forest
Deschutes National Forest
The Deschutes National Forest is a United States National Forest located in parts of Deschutes, Klamath, Lake, and Jefferson counties in central Oregon. It comprises 1.8 million acres along the east side of the Cascade mountains. In 1908, the Deschutes National Forest was established from parts...
.
The forest surrounding the cave entrance is dominated by large ponderosa pine
Ponderosa Pine
Pinus ponderosa, commonly known as the Ponderosa Pine, Bull Pine, Blackjack Pine, or Western Yellow Pine, is a widespread and variable pine native to western North America. It was first described by David Douglas in 1826, from eastern Washington near present-day Spokane...
trees with sagebrush
Sagebrush
Sagebrush is a common name of a number of shrubby plant species in the genus Artemisia native to western North America;Or, the sagebrush steppe ecoregion, having one or more kinds of sagebrush, bunchgrasses and others;...
, manzanita
Manzanita
Manzanita is a common name for many species of the genus Arctostaphylos. They are evergreen shrubs or small trees present in the chaparral biome of western North America, where they occur from southern British Columbia, Washington to California, Arizona and New Mexico in the United States, and...
, bitterbrush, snowbrush
Ceanothus
Ceanothus L. is a genus of about 50–60 species of shrubs or small trees in the buckthorn family Rhamnaceae. The genus is confined to North America, the center of its distribution in California, with some species in the eastern United States and southeast Canada, and others extending as far south...
, and chokecherries as the main ground cover. Along the short path leading from the forest floor down to the cave entrance, visitor will also find serviceberry
Serviceberry
Amelanchier , also known as shadbush, shadwood or shadblow, serviceberry or sarvisberry, wild pear, juneberry, saskatoon, sugarplum or wild-plum, and chuckley pear is a genus of about 20 species of deciduous-leaved shrubs and small trees in the Rose family .Amelanchier is native to temperate regions...
, False Solomon Seal, squaw currant
Ribes
Ribes is a genus of about 150 species of flowering plants native throughout the temperate regions of the Northern Hemisphere. It is usually treated as the only genus in the family Grossulariaceae. Seven subgenera are recognized....
, Oregon grape, and small willow
Willow
Willows, sallows, and osiers form the genus Salix, around 400 species of deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions of the Northern Hemisphere...
trees.
Animals common in the forest around the cave include Golden-mantled Ground Squirrel
Golden-mantled Ground Squirrel
The golden-mantled ground squirrel, Callospermophilus lateralis, is a type of ground squirrel found in mountainous areas of western North America. It eats seeds, nuts, berries, insects, and underground fungi. It is preyed upon by hawks, jays, weasels, foxes, bobcats, and coyotes. A typical adult...
s, chipmunk
Chipmunk
Chipmunks are small striped squirrels native to North America and Asia. They are usually classed either as a single genus with three subgenera, or as three genera.-Etymology and taxonomy:...
s, western gray squirrel
Western Gray Squirrel
The Western Gray Squirrel is an arboreal rodent found along the western coast of the United States and Canada.In some places, this species has also been known as the Silver-gray Squirrel, the California Gray Squirrel, the Oregon Gray Squirrel, the Columbian Gray Squirrel and the Banner-tail...
s, porcupine
Porcupine
Porcupines are rodents with a coat of sharp spines, or quills, that defend or camouflage them from predators. They are indigenous to the Americas, southern Asia, and Africa. Porcupines are the third largest of the rodents, behind the capybara and the beaver. Most porcupines are about long, with...
s, weasel
Weasel
Weasels are mammals forming the genus Mustela of the Mustelidae family. They are small, active predators, long and slender with short legs....
s, pine marten
Pine Marten
The European Pine Marten , known most commonly as the pine marten in Anglophone Europe, and less commonly also known as Pineten, baum marten, or sweet marten, is an animal native to Northern Europe belonging to the mustelid family, which also includes mink, otter, badger, wolverine and weasel. It...
s, and mule deer
Mule Deer
The mule deer is a deer indigenous to western North America. The Mule Deer gets its name from its large mule-like ears. There are believed to be several subspecies, including the black-tailed deer...
. In 1991, park personnel observed a full-grown cougar ran out of the cave entrance area, but that was a single sighting. There is also a wide range of resident and migratory bird species common to the area. Small resident birds include wren
Wren
The wrens are passerine birds in the mainly New World family Troglodytidae. There are approximately 80 species of true wrens in approximately 20 genera....
s, robin
American Robin
The American Robin or North American Robin is a migratory songbird of the thrush family. It is named after the European Robin because of its reddish-orange breast, though the two species are not closely related, with the European robin belonging to the flycatcher family...
s, junco
Junco
A Junco , genus Junco, is a small North American bird. Junco systematics are still confusing after decades of research, with various authors accepting between three and twelve species...
s, thrush
Thrush (bird)
The thrushes, family Turdidae, are a group of passerine birds that occur worldwide.-Characteristics:Thrushes are plump, soft-plumaged, small to medium-sized birds, inhabiting wooded areas, and often feed on the ground or eat small fruit. The smallest thrush may be the Forest Rock-thrush, at and...
es, woodpecker
Woodpecker
Woodpeckers are near passerine birds of the order Piciformes. They are one subfamily in the family Picidae, which also includes the piculets and wrynecks. They are found worldwide and include about 180 species....
s, sapsucker
Sapsucker
The Sapsuckers form the genus Sphyrapicus within the woodpecker family Picidae. All are found in North America.As their name implies, sapsuckers feed primarily on the sap of trees, moving among different tree and shrub species on a seasonal basis...
s, red-shafted flickers, and ruby-crowned kinglets. Larger birds include great horned owl
Great Horned Owl
The Great Horned Owl, , also known as the Tiger Owl, is a large owl native to the Americas. It is an adaptable bird with a vast range and is the most widely distributed true owl in the Americas.-Description:...
s, red-tailed hawk
Red-tailed Hawk
The Red-tailed Hawk is a bird of prey, one of three species colloquially known in the United States as the "chickenhawk," though it rarely preys on standard sized chickens. It breeds throughout most of North America, from western Alaska and northern Canada to as far south as Panama and the West...
s, vulture
New World vulture
The New World Vulture or Condor family Cathartidae contains seven species in fivegenera, all but one of which are monotypic. It includes five vultures and two condors found in warm and temperate areas of the Americas....
s, and a few golden eagle
Golden Eagle
The Golden Eagle is one of the best known birds of prey in the Northern Hemisphere. Like all eagles, it belongs to the family Accipitridae. Once widespread across the Holarctic, it has disappeared from many of the more heavily populated areas...
s.
Forest Service biologists have identified several species of spiders, worm
Worm
The term worm refers to an obsolete taxon used by Carolus Linnaeus and Jean-Baptiste Lamarck for all non-arthropod invertebrate animals, and stems from the Old English word wyrm. Currently it is used to describe many different distantly-related animals that typically have a long cylindrical...
s, centipedes, and millipede
Millipede
Millipedes are arthropods that have two pairs of legs per segment . Each segment that has two pairs of legs is a result of two single segments fused together as one...
s that live inside the cave. There are also mice
MICE
-Fiction:*Mice , alien species in The Hitchhiker's Guide to the Galaxy*The Mice -Acronyms:* "Meetings, Incentives, Conferencing, Exhibitions", facilities terminology for events...
and bat
Bat
Bats are mammals of the order Chiroptera "hand" and pteron "wing") whose forelimbs form webbed wings, making them the only mammals naturally capable of true and sustained flight. By contrast, other mammals said to fly, such as flying squirrels, gliding possums, and colugos, glide rather than fly,...
s that live in the cave year around. The cave's bat population is relatively small and the bats are very shy so visitors rarely see them. In fact, bats usually remain in hibernation
Hibernation
Hibernation is a state of inactivity and metabolic depression in animals, characterized by lower body temperature, slower breathing, and lower metabolic rate. Hibernating animals conserve food, especially during winter when food supplies are limited, tapping energy reserves, body fat, at a slow rate...
until July, and when active they are nocturnal so they are asleep during the day when the cave is open. If a bat is sighted, the Forest Service recommended that it be left undisturbed. Waking it from hibernation is extremely stressful, and can cause the bat to die from the sudden expenditure of energy.
History
The presence of obsidian flakes near the cave has led archaeologists to conclude that Native Americans knew about the caves long before any pioneers arrived in the Oregon countryOregon Country
The Oregon Country was a predominantly American term referring to a disputed ownership region of the Pacific Northwest of North America. The region was occupied by British and French Canadian fur traders from before 1810, and American settlers from the mid-1830s, with its coastal areas north from...
. The first recorded discovery is credited to a local settler named Leander Dillman, who found the cave opening on a hunting trip in 1889. Legend has it that Dillman found the cave entrance while following a wounded deer. After its discovery, he used the cave to cool his venison. The cave acquired its name from a 1923 geology study published by Ira A. Williams. The study also provided the first map of the cave.
In 1926, the Shevlin-Hixon Lumber Company donated the 22.5 acres (91,054.4 m²) site around the cave entrance to the State of Oregon for a park. In 1981, the cave and above ground park area were acquired by the Forest Service as part of a land exchange with the State government. In November 1990, the cave was incorporated into the Newberry National Volcanic Monument. However, it is still managed by the Forest Service along with the rest of the Newberry monument area.
Cave tour
The cave's entrance appears as a large hole in the ground. At its mouth, the entrance trail drops suddenly over a jumble of volcanic rocks. This area is known as the Collapsed Corridor. It is the result of ground water freezing in rock cracks in the ceiling. Loosened rocks eventually fall. Over the centuries, the fallen rocks have accumlated into a large boulder pile. Since freezing temperatures occurs only near the mouth of the cave, most rock-falls are in this area. To get down the rock pile, visitor must descend 126 steps with guard rails for safety. At the bottom of the stairs is a large cool chamber where winter ice fills cracks in the floor and ice stalactites often cling to the ceiling until June.
After a short walk, the ceiling reaches a height of 58 feet (18 m). At this point, the width of the cave is 50 feet (15 m). This massive volcanic archway is called Echo Hall. The smooth walls are remarkably symmetrical so sounds echo in the huge chamber. In this section, remnants of the ancient lava flow’s current can be seen molded in the tunnel walls. They appear as rounded over-hanging shelves and lateral markings etched in the walls. The end of this hall is about 1,500 feet (457 m) into the cave. At that point, the cave passes under Highway 97. The underground crossing is marked by a small sign post.
Lava channel
A lava channel is a stream of fluid lava contained within marginal zones of static lava or levees. The initial channel may not contain levees per se, until the parental flow solidifies over what develops into the channel and creates simple levees. This initial levee allows for the building of a...
s at the same time; however, the upper channel eventually drained into the lower tube as the flow subsided.
One of the most unique parts of the cave is the Sand Garden, located about 3,000 feet (914 m) from the entrance. Here the floor of the cave is covered with sand. The sand was carried into the cave by dripping water. The sand is fine volcanic ash from the eruption of Mount Mazama
Mount Mazama
Mount Mazama is a destroyed stratovolcano in the Oregon part of the Cascade Volcanic Arc and the Cascade Range. The volcano's collapsed caldera holds Crater Lake, and the entire mountain is located within Crater Lake National Park....
6,600 years ago. Rain and melting snow carried the ash down from the surface through cracks in the rock and deposited it on the floor of the cave one grain at a time. Occasionally, enough water leaks into the cave to create a pool. This allows the sand to spread out across the floor. At the Sand Garden, the constant dripping of water has carved spires and pinnacles in the sand. Since it takes hundreds of years to build these delicate sand forms, the Forest Service has fenced off the garden area to protect it. The 2,211 feet (674 m) of cave trail beyond the Sand Garden has a sandy floor. Along the way, the ceiling descends lower and lower until the sand fills the cave. The last 310 feet (95 m) of the cave was dug out of the sand plug by two men in the 1930s. Exploring this section of the cave requires visitors to crawl on hands and knees for much of the distance to the cave’s end, and usually takes at least thirty minutes.
The air temperature at the mouth of the cave ranges from about 32 degrees to around 45 degrees Fahrenheit (-1 degrees to around 7 degrees Celsius) depending on the time of year. Inside the cave, it is a constant 42 degrees (5.6 degrees Celsius). As a result, the Forest Service strongly recommends that visitors wear a warm jacket while exploring the cave. Lanterns can be rented at the visitor center above the cave entrance. Personal lanterns are also permitted; however, in order to protect the cave’s fragile environment, they cannot have glass globes or use kerosene or white gas. Battery powered lights are best, but they must provide reliable illumination for at least one hour.