Geothermal areas in Lassen Volcanic National Park
Encyclopedia
Several groups of hot spring
s and fumarole
s, remnants of former volcanic activity, exist in Lassen Volcanic National Park
. Most of these lie in or are closely adjacent to Mount Tehama
's caldera. Bumpass Hell is the most spectacular of these, but others of importance are Sulphur Works, Little Hot Springs Valley, Boiling Springs Lake and Devil's Kitchen. In each thermal area, the highest temperature of water generally is close to the boiling temperature at the altitude of the particular spring or fumarole—198 °F (92 °C) at Bumpass Hell and 191 °F (88 °C) on the northwest flanks of Lassen Peak. Temperatures as high as 230 °F (110 °C) have been recorded in the park.
Spring activity varies with water supply. Abundant water results in clear springs during early summer, but as the season progresses and the water supply decreases, springs change successively to turbid, warm pools, spattering mudpot
s, and finally steaming fumaroles. There are no true geyser
s within Lassen Volcanic National Park.
Gases from hot springs are composed mostly of steam
and carbon dioxide
, with minor amounts of other gases. These react with the rocks around the springs to ultimately form opal
if temperature and acidity are high, and kaolin if they are low. Deposits of sulfur
, iron pyrite (fool's gold), quartz
and other substances are also found around the springs and in their runoff channels.
Solfataric alternation within the caldera of Mount Tehama covers about five square miles, much more extensive than the present hot springs basins—indicative of its former extent, and suggestive of its waning activity. It is the altered materials in the caldera which yielded most readily to the forces of erosion
. Diamond Peak is a body of unaltered rock which still remains because it is more resistant.
have been chemically altered into bright-colored clay
s. Sulfurous acid
and sulfuric acid
have broken down hard, gray-green andesite
lavas into red, yellow and buff clays and iron oxide
s. Many visitors pass through Sulphur Works on their way north on State Route 89
and sense the rotten-egg smell (hydrogen sulfide
) when they pass by a hot vent to the east of the road. Sulphur Works is said to be the volcanic center of the ancestral Mount Tehama
.
s, fumarole
s, and mud pots. Never part of Mount Tehama
's main vent, Bumpass Hell is the result of fissures that tap the volcanic heat (which is thought to be a cooling mass of andesite
, perhaps three miles (5 km) below the surface).
It is named after Kendall Vanhook Bumpass, a cowboy
who worked in the Lassen area in the 1860s. One day Bumpass stumbled upon the area and his leg was badly scalded when it broke though a thin crust above a mud pot. He told his friends and townspeople about it, describing it as "hell." A newspaper editor was interested in the story and convinced Bumpass to take him to this place. Unfortunately, Bumpass' leg broke through the crust again - this time it had to be amputated
.
ic that they have eaten pits and holes in the bedrock
.
, but rather a cold stream flowing over a steam vent. This is about 100 feet (30 m) from the site of a geothermal drilling
operation that took place in 1962 and 1978. The 4,008-foot (1,222 m) well is now plugged and abandoned.
s or signs and offers a chance to view thermal features in a more natural setting.
Hot spring
A hot spring is a spring that is produced by the emergence of geothermally heated groundwater from the Earth's crust. There are geothermal hot springs in many locations all over the crust of the earth.-Definitions:...
s and fumarole
Fumarole
A fumarole is an opening in a planet's crust, often in the neighborhood of volcanoes, which emits steam and gases such as carbon dioxide, sulfur dioxide, hydrochloric acid, and hydrogen sulfide. The steam is created when superheated water turns to steam as its pressure drops when it emerges from...
s, remnants of former volcanic activity, exist in Lassen Volcanic National Park
Lassen Volcanic National Park
Lassen Volcanic National Park is a United States National Park in northeastern California. The dominant feature of the park is Lassen Peak; the largest plug dome volcano in the world and the southern-most volcano in the Cascade Range...
. Most of these lie in or are closely adjacent to Mount Tehama
Mount Tehama
Mount Tehama is an eroded andesitic stratovolcano in the Cascade Volcanic Arc and the Cascade Range in Northern California. Part of the Lassen volcanic center, its highest remaining remnant, Brokeoff Mountain, is itself the second highest peak in Lassen Volcanic National Park and connects to the...
's caldera. Bumpass Hell is the most spectacular of these, but others of importance are Sulphur Works, Little Hot Springs Valley, Boiling Springs Lake and Devil's Kitchen. In each thermal area, the highest temperature of water generally is close to the boiling temperature at the altitude of the particular spring or fumarole—198 °F (92 °C) at Bumpass Hell and 191 °F (88 °C) on the northwest flanks of Lassen Peak. Temperatures as high as 230 °F (110 °C) have been recorded in the park.
Spring activity varies with water supply. Abundant water results in clear springs during early summer, but as the season progresses and the water supply decreases, springs change successively to turbid, warm pools, spattering mudpot
Mudpot
A mudpot, mud pool or paint pot is a sort of hot spring or fumarole consisting of a pool of usually bubbling mud. The mud is generally of white to greyish color, but is sometimes stained with reddish or pink spots from iron compounds...
s, and finally steaming fumaroles. There are no true geyser
Geyser
A geyser is a spring characterized by intermittent discharge of water ejected turbulently and accompanied by a vapour phase . The word geyser comes from Geysir, the name of an erupting spring at Haukadalur, Iceland; that name, in turn, comes from the Icelandic verb geysa, "to gush", the verb...
s within Lassen Volcanic National Park.
Gases from hot springs are composed mostly of steam
Steam
Steam is the technical term for water vapor, the gaseous phase of water, which is formed when water boils. In common language it is often used to refer to the visible mist of water droplets formed as this water vapor condenses in the presence of cooler air...
and carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
, with minor amounts of other gases. These react with the rocks around the springs to ultimately form opal
Opal
Opal is an amorphous form of silica related to quartz, a mineraloid form, not a mineral. 3% to 21% of the total weight is water, but the content is usually between 6% to 10%. It is deposited at a relatively low temperature and may occur in the fissures of almost any kind of rock, being most...
if temperature and acidity are high, and kaolin if they are low. Deposits of sulfur
Sulfur
Sulfur or sulphur is the chemical element with atomic number 16. In the periodic table it is represented by the symbol S. It is an abundant, multivalent non-metal. Under normal conditions, sulfur atoms form cyclic octatomic molecules with chemical formula S8. Elemental sulfur is a bright yellow...
, iron pyrite (fool's gold), quartz
Quartz
Quartz is the second-most-abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz,...
and other substances are also found around the springs and in their runoff channels.
Solfataric alternation within the caldera of Mount Tehama covers about five square miles, much more extensive than the present hot springs basins—indicative of its former extent, and suggestive of its waning activity. It is the altered materials in the caldera which yielded most readily to the forces of erosion
Erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...
. Diamond Peak is a body of unaltered rock which still remains because it is more resistant.
Sulphur Works and Little Hot Springs Valley
As in many hydrothermally active areas, the rocks at Sulphur Works and Little Hot Springs Valley in Lassen Volcanic National ParkLassen Volcanic National Park
Lassen Volcanic National Park is a United States National Park in northeastern California. The dominant feature of the park is Lassen Peak; the largest plug dome volcano in the world and the southern-most volcano in the Cascade Range...
have been chemically altered into bright-colored clay
Clay
Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...
s. Sulfurous acid
Sulfurous acid
Sulfurous acid is the chemical compound with the formula H2SO3. There is no evidence that sulfurous acid exists in solution, but the molecule has been detected in the gas phase...
and sulfuric acid
Sulfuric acid
Sulfuric acid is a strong mineral acid with the molecular formula . Its historical name is oil of vitriol. Pure sulfuric acid is a highly corrosive, colorless, viscous liquid. The salts of sulfuric acid are called sulfates...
have broken down hard, gray-green andesite
Andesite
Andesite is an extrusive igneous, volcanic rock, of intermediate composition, with aphanitic to porphyritic texture. In a general sense, it is the intermediate type between basalt and dacite. The mineral assemblage is typically dominated by plagioclase plus pyroxene and/or hornblende. Magnetite,...
lavas into red, yellow and buff clays and iron oxide
Iron oxide
Iron oxides are chemical compounds composed of iron and oxygen. All together, there are sixteen known iron oxides and oxyhydroxides.Iron oxides and oxide-hydroxides are widespread in nature, play an important role in many geological and biological processes, and are widely utilized by humans, e.g.,...
s. Many visitors pass through Sulphur Works on their way north on State Route 89
California State Route 89
State Route 89 is a California State Highway that travels in the north–south direction, and is the major thoroughfare for many mountain communities. It starts from U.S. Route 395 near Topaz Lake, winding its way up to the Monitor Pass, down to the Carson River, and up again over the Luther...
and sense the rotten-egg smell (hydrogen sulfide
Hydrogen sulfide
Hydrogen sulfide is the chemical compound with the formula . It is a colorless, very poisonous, flammable gas with the characteristic foul odor of expired eggs perceptible at concentrations as low as 0.00047 parts per million...
) when they pass by a hot vent to the east of the road. Sulphur Works is said to be the volcanic center of the ancestral Mount Tehama
Mount Tehama
Mount Tehama is an eroded andesitic stratovolcano in the Cascade Volcanic Arc and the Cascade Range in Northern California. Part of the Lassen volcanic center, its highest remaining remnant, Brokeoff Mountain, is itself the second highest peak in Lassen Volcanic National Park and connects to the...
.
Bumpass Hell
Near Little Hot Springs Valley is Bumpass Hell, which is a hydrothermally altered geothermal area that spans 16 acres (65,000 m²) and has hot springHot spring
A hot spring is a spring that is produced by the emergence of geothermally heated groundwater from the Earth's crust. There are geothermal hot springs in many locations all over the crust of the earth.-Definitions:...
s, fumarole
Fumarole
A fumarole is an opening in a planet's crust, often in the neighborhood of volcanoes, which emits steam and gases such as carbon dioxide, sulfur dioxide, hydrochloric acid, and hydrogen sulfide. The steam is created when superheated water turns to steam as its pressure drops when it emerges from...
s, and mud pots. Never part of Mount Tehama
Mount Tehama
Mount Tehama is an eroded andesitic stratovolcano in the Cascade Volcanic Arc and the Cascade Range in Northern California. Part of the Lassen volcanic center, its highest remaining remnant, Brokeoff Mountain, is itself the second highest peak in Lassen Volcanic National Park and connects to the...
's main vent, Bumpass Hell is the result of fissures that tap the volcanic heat (which is thought to be a cooling mass of andesite
Andesite
Andesite is an extrusive igneous, volcanic rock, of intermediate composition, with aphanitic to porphyritic texture. In a general sense, it is the intermediate type between basalt and dacite. The mineral assemblage is typically dominated by plagioclase plus pyroxene and/or hornblende. Magnetite,...
, perhaps three miles (5 km) below the surface).
It is named after Kendall Vanhook Bumpass, a cowboy
Cowboy
A cowboy is an animal herder who tends cattle on ranches in North America, traditionally on horseback, and often performs a multitude of other ranch-related tasks. The historic American cowboy of the late 19th century arose from the vaquero traditions of northern Mexico and became a figure of...
who worked in the Lassen area in the 1860s. One day Bumpass stumbled upon the area and his leg was badly scalded when it broke though a thin crust above a mud pot. He told his friends and townspeople about it, describing it as "hell." A newspaper editor was interested in the story and convinced Bumpass to take him to this place. Unfortunately, Bumpass' leg broke through the crust again - this time it had to be amputated
Amputation
Amputation is the removal of a body extremity by trauma, prolonged constriction, or surgery. As a surgical measure, it is used to control pain or a disease process in the affected limb, such as malignancy or gangrene. In some cases, it is carried out on individuals as a preventative surgery for...
.
Devils Kitchen
About seven miles (11 km) southeast of Lassen Peak is Devils Kitchen. In this geothermal area the hot springs are so acidAcid
An acid is a substance which reacts with a base. Commonly, acids can be identified as tasting sour, reacting with metals such as calcium, and bases like sodium carbonate. Aqueous acids have a pH of less than 7, where an acid of lower pH is typically stronger, and turn blue litmus paper red...
ic that they have eaten pits and holes in the bedrock
Bedrock
In stratigraphy, bedrock is the native consolidated rock underlying the surface of a terrestrial planet, usually the Earth. Above the bedrock is usually an area of broken and weathered unconsolidated rock in the basal subsoil...
.
Terminal Geyser
Located in the southeast corner of the park, Terminal Geyser is not actually a geyserGeyser
A geyser is a spring characterized by intermittent discharge of water ejected turbulently and accompanied by a vapour phase . The word geyser comes from Geysir, the name of an erupting spring at Haukadalur, Iceland; that name, in turn, comes from the Icelandic verb geysa, "to gush", the verb...
, but rather a cold stream flowing over a steam vent. This is about 100 feet (30 m) from the site of a geothermal drilling
Drilling
Drilling is a cutting process that uses a drill bit to cut or enlarge a hole in solid materials. The drill bit is a multipoint, end cutting tool...
operation that took place in 1962 and 1978. The 4,008-foot (1,222 m) well is now plugged and abandoned.
Boiling Springs Lake
Just northwest of Terminal Geyser, large, warm-water Boiling Springs Lake has many hot springs, mudpots, and fumaroles along its west shore. Unlike the more heavily visited areas of the park, this area is not developed with boardwalkBoardwalk
A boardwalk, in the conventional sense, is a wooden walkway for pedestrians and sometimes vehicles, often found along beaches, but they are also common as paths through wetlands, coastal dunes, and other sensitive environments....
s or signs and offers a chance to view thermal features in a more natural setting.
See also
- Geology of the Lassen area
- Geothermal areas of YellowstoneGeothermal areas of YellowstoneThe geothermal areas of Yellowstone include several geyser basins in Yellowstone National Park as well as other geothermal features such as hot springs, mud pots, and fumaroles...
- Lassen PeakLassen PeakLassen Peak is the southernmost active volcano in the Cascade Range. It is part of the Cascade Volcanic Arc which is an arc that stretches from northern California to southwestern British Columbia...
- Lassen Volcanic National ParkLassen Volcanic National ParkLassen Volcanic National Park is a United States National Park in northeastern California. The dominant feature of the park is Lassen Peak; the largest plug dome volcano in the world and the southern-most volcano in the Cascade Range...
- Volcanic Legacy Scenic BywayVolcanic Legacy Scenic BywayThe Volcanic Legacy Scenic Byway is an All-American Road in the U.S. states of California and Oregon. It is roughly 500 miles long and travels through the Cascade Range past numerous volcanoes. It is composed of two separate National Scenic Byways, the Volcanic Legacy Scenic Byway - Oregon and...