What are the most recent eruptions in the Lassen area?
The most recent eruptions in the Lassen area were the relatively small events that occurred at Lassen Peak between 1914 and 1917. The most recent large eruption produced Chaos Crags about 1,100 years ago.
How long ago did Lassen Peak form?
Lassen Peak's lava dome formed about 27,000 years ago from a series of eruptions over a few years, undergoing significant glacial erosion between 25,000 and 18,000 years ago.
When does Lassen Peak open for hiking?
As the second-tallest volcano in Northern California, trailing only Mount Shasta, Lassen Peak is frequently visited by climbers and hikers from around the world. The summit opens for use most years near the end of June, remaining in use until heavy snow falls in October or November.
How much snow does it snow on Lassen Peak?
There is an average annual snowfall of 660 in (1,676 cm), and in some years, more than 1,000 in (2,500 cm) of snow falls at its base elevation of 8,250 ft (2,515 m) at Lake Helen. The Lassen Peak area receives more precipitation ( rain, sleet, hail, snow, etc.) than anywhere in the Cascade Range south of the Three Sisters volcanoes in Oregon.
How many times has Mt Lassen erupted?
In total, about 400 eruptions were observed between 1914 and 1921, which were the last eruptions in the Cascades before the 1980 eruption of Mount St. Helens, which was the only other volcanic eruption in the contiguous United States during the 20th century.
When did Lassen Peak last erupt?
1921Lassen Peak / Last eruptionThe most recent eruptive activity at Lassen Peak (California) took place in 1914-1917. This eruptive episode began on May 30, 1914, when a small phreatic eruption occurred at a new vent near the summit of the peak. More than 150 explosions of various sizes occurred during the following year.
Will Lassen Peak erupt again?
Q: Will Lassen Peak erupt again and if so, when? A: No one can say for sure or when. However, Lassen Peak is considered active because it last erupted about 100 years ago (read more). Geologically recent volcanic activity in an area is the best guide to forecasting future eruptions.
How long did Lassen Peak erupt?
That first explosion created a small crater at the summit of Lassen Peak, and each of more than 180 subsequent steam explosions enlarged it. Over more than 11 months, these steam explosions blasted out a crater 1,000 feet across.
What are the 7 volcanoes in California?
At least seven California volcanoes—Medicine Lake Volcano, Mount Shasta, Lassen Volcanic Center, Clear Lake Volcanic Field, Long Valley Volcanic Region, Coso Volcanic Field, and Salton Buttes - have partially molten rock (magma) deep within their roots, and research on past eruptions indicates they will erupt again in ...
How many people died when Lassen Peak erupted?
A ring of fire Volcanoes in the Lassen, Shasta and Long Valley areas are capable of producing pyroclastic flows or surges when they do erupt — fast-moving flows of hot ash, rock and gas sweeping down the sides of mountains, of the type that killed 57 people when Mt.
What would happen if Lassen erupted?
When Lassen erupted from 1914 to 1917, very few people lived in the area. Areas affected or could be affected by an eruption have considerably more people today, Clynne said. Infrastructure would be impacted, he said. Roads and highways would be covered with lava and other debris making travel difficult.
What was the last volcano to erupt in California?
Lassen PeakThe last series of eruptions in California occurred from 1914 to 1917 within the Lassen Volcanic Center, with an explosive eruption of Lassen Peak on May 22, 1915.
Can Lassen erupt?
Volcanoes in the Lassen area tend to erupt infrequently, and may be inactive for periods lasting centuries or even millennia. The most recent eruptions in the Lassen area were the relatively small events that occurred at Lassen Peak between 1914 and 1917.
When was the last volcano in California?
California last experienced a volcanic eruption on May 22, 1915, when Mount Lassen sent pulverizing streams of volcanic debris down its slopes. The southernmost active volcano in the Cascade Range, Lassen rises roughly 10,400 feet just east of Redding.
What was the last volcano to erupt?
Bottom line: Kilauea volcano's most recent eruption began on December 20, 2020, around 9:30 p.m. local time (07:30 UTC on December 21). The eruption sent lava fountains shooting nearly 165 feet (50 meters) into the sky and created a new lava lake.
Will Mt Shasta erupt?
On the basis of its behavior in the past 10,000 years, Mount Shasta is not likely to erupt large volumes of pumiceous ash in the near future.
When was the last volcanic eruption California?
California last experienced a volcanic eruption on May 22, 1915, when Mount Lassen sent pulverizing streams of volcanic debris down its slopes. The southernmost active volcano in the Cascade Range, Lassen rises roughly 10,400 feet just east of Redding.
What year did Lassen erupt?
May 22, 1915On May 22, 1915, an explosive eruption at Lassen Peak, the southernmost active volcano in the Cascade Range, devastated nearby areas and rained volcanic ash as far away as 200 miles to the east.
What was the last volcano to erupt?
Bottom line: Kilauea volcano's most recent eruption began on December 20, 2020, around 9:30 p.m. local time (07:30 UTC on December 21). The eruption sent lava fountains shooting nearly 165 feet (50 meters) into the sky and created a new lava lake.
Is Mount Shasta still active?
Shasta is an active volcano that has erupted at least once per 800 years for the past 10,000 years, with an increased eruption frequency of about once per 250 years over the past 750 years. The region around Mt. Shasta is susceptible to lava and pyroclastic flows, lahars (mudflows), avalanches, and earthquakes.
How many eruptions have occurred in the Lassen region?
The Lassen region of the southernmost Cascade Range is an active volcanic area. At least 70 eruptions have occurred in the past 100,000 years, including 3 in the past 1,000 years, most recently in 1915.
How far away was the Lassen Peak eruption?
The fall of fine ash was reported as far away as Elko, Nevada - more than 500 kilometers east of Lassen Peak. Intermittent eruptions of variable intensity continued until about the middle of 1917.
What happened to Lassen Peak in 1915?
Disruption of the sticky lava on the upper east side of Lassen Peak on May 19 resulted in an avalanche of hot rock onto a snowfield. This generated a lahar that travelled more than 18 kilometers down Lost Creek. On May 22, an explosive eruption produced a pyroclastic flow that devastated an area as far as 6 kilometers northeast of the summit.
How many eruptions have occurred in California in the past 1,000 years?
At least 10 eruptions have taken place in California in the past 1,000 years—most recently at Lassen Peak in Lassen Volcanic National Park (1914 to 1917) in the northern part of the State—and future... Stovall, Wendy K.; Marcaida, Mae; Mangan, Margaret T.
What year was Lassen Peak lava exploded?
Lassen Volcanic National Park, California. Northeast side of Lassen Peak, showing the area devastated by mudflows and a lateral blast in 1915. 1977.
Where is the fumarole gas sample?
USGS geologist Deborah Bergfeld collects a gas sample from a superheated (hotter than the boiling point) fumarole in Little Hot Springs Valley at Lassen Volcanic National Park.
Where are Lahar hazard zones?
Year Published: 2012. Lahar hazard zones for eruption-generated lahars in the Lassen Volcanic Center, California. Lahar deposits are found in drainages that head on or near Lassen Peak in northern California, demonstrating that these valleys are susceptible to future lahars.
How did Lassen Peak form?
These lava domes formed as a result of rising lava that was pushed up but was too viscous to escape its source, creating steep edifices. Lassen Peak's lava dome formed 27,000 years ago from a series of eruptions over a few years, undergoing significant glacial erosion between 25,000 and 18,000 years ago.
What type of volcanoes formed in the Lassen area?
Shortly after, the Lassen volcanic center, a cluster of closely spaced volcanoes, formed in the area, covering the nearby caldera. During the late Pleistocene it produced andesite lava flows that built the Brokeoff composite volcano (stratovolcano).
How high is the cinder cone?
Cinder Cone, which reaches an elevation of 700 ft (210 m) above its surrounding area in the northeastern region of the Lassen Volcanic National Park, forms a symmetrical pyroclastic cone. The youngest mafic volcano in the Lassen volcanic center, it is surrounded by unvegetated block lava and has concentric craters at its summit. Cinder Cone is comprised by five basaltic andesite and andesite lava flows, and it also has two cinder cone volcanoes, with two scoria cones, the first of which was mostly destroyed by lava flows from its base. In 1850 and 1851, a number of observers reported an eruption at Cinder Cone visible from more than 40 mi (64 km) away, with one observer near the mountain claiming to have observed a lava flow "running down the sides of the volcano." However, despite these testimonies and accounts in newspaper articles and several scientific journals, the veracity of these eruptions has been questioned by scientists from the United States Geological Survey. In addition to the fact that cinder cones usually erupt lava from base vents, there is a lack of physical evidence suggesting activity at the volcano since its formation in 1650. In addition, an old willow bush growing near the summit crater that was documented during the 1850s was still present in the 1880s after the alleged eruptions, suggesting that no eruptions took place during the 1850s.
What type of rock is found in the southern Cascades?
In the southern segment of the Cascades, volcanoes exhibit widespread and long-lived activity produced by magma that ranges from low- silica basalt to siliceous (silica-rich) rhyolite. The Lassen volcanic center is fed by two magma chambers, one calc-alkaline reservoir common to the rest of the Cascade Volcanoes, and the other a smaller volume of low-potassium olivine tholeiitic basalt associated with the Basin and Range province. Within the region, most if not all of the volcanic rock has erupted in the past 3 million years. During this period, at least five large andesitic stratovolcanoes (such as Mount Maidu) formed in the vicinity of Lassen Volcanic National Park, building volcanic cones before going extinct and undergoing erosion. For most volcanic centers in the Southern Cascades, one volcano becomes active and normally becomes extinct as another begins to erupt, but at the Lassen locus, the Maidu and Dittmar volcanic centers overlapped during the late Pliocene to the early Pleistocene. Volcanism within the Lassen vicinity follows a trend of intermittent, episodic eruptions punctuating long periods of dormancy, a pattern which persisted through the late Pleistocene and Holocene. During the past 825,000 years, the area has produced hundreds of explosive eruptions over an area of 200 sq mi (520 km 2 ), and the past 50,000 years have seen seven major silicic eruptive episodes that produced dacitic lava domes, tephra, and pyroclastic flows, along with five periods of basaltic and andesitic lava flows.
How did the Chaos Crags form?
They were produced by vigorous explosive eruptions of pumice and ash followed by effusive activity, which created unstable edifices that partially collapsed and formed pyroclastic flows made of incandescent lava blocks and lithic ash. Six domes were originally formed, though one was destroyed by a pyroclastic flow. Roughly 350 years ago, one of the domes collapsed to produce the Chaos Jumbles, an area where three enormous rockfalls transformed the local area and traveled as far as 4 mi (6.4 km) down the dome's slopes.
What is the largest lava dome in the world?
A lava dome, Lassen Peak has a volume of 0.6 cu mi (2.5 km 3) making it the largest lava dome on Earth. The volcano arose from the former northern flank of now-eroded Mount Tehama about 27,000 years ago, from a series of eruptions over the course of a few years. The mountain has been significantly eroded by glaciers over the last 25,000 years, and is now covered in talus deposits.
How tall is Lassen Peak?
It represents one of the largest lava domes on Earth, with a height of 2,000 ft (610 m) above its surroundings , and an approximate volume of 0.60 cu mi (2.5 km 3 ).
What type of volcano is Lassen domefield?
Between about 385 and 315 ka the character and locus of volcanism in the Lassen Volcanic Center changed dramatically from the andesitic stratocone to the Lassen domefield, which consists of a core of dacite domessurrounded by an arc of hybrid andesite flows. The dacite domes erupted along the northern flank of Brokeoff Volcano and are divided on the basis of age into the Bumpass (~300–190 ka) and Eagle Peak (~70–0 ka) sequences. The hybrid andesite units erupted in two groups called the older (~315–~240 ka) and younger (~90–0 ka) Twin Lakes sequence and are contemporaneous with the Bumpass and Eagle Peak sequences, respectively. No volcanism is known in the LVC during the period 190–90 ka.
What is the name of the volcano that erupted in the Rockland Tephra eruption?
Brokeoff Volcano, also designated “Mount Tehama” by the National Park Service, consists of a large, 80-km 3 (19.2 mi 3) composite volcano. Almost immediately after eruption of the Rockland tephra, its caldera began to fill as renewed activity formed Brokeoff Volcano. The stratigraphy of Brokeoff Volcano is described by Clynne and Muffler (USGS Scientific Investigations Map 2899) as two sequences of deposits: the Mill Canyon sequence and the Diller sequence. The Mill Canyon sequence consists of dozens of small-volume basaltic andesite to dacite lavaflows and interlaid layers of explosive deposits erupted from a central vent between about 590 and 470 ka. The Diller sequence consists primarily of 6 thick, large-volume, lithologically similar, lava flows that erupted from flank vents between 470 and 385 ka.
What are the names of the mountains in the Eagle Peak sequence?
Reading Peak, Bumpass Mountain, Mount, Crescent Crater, and hill 8283 are part of the Bumpass sequence. The flow of Kings Creek, Lassen Peak, and Chaos Crags are part of the Eagle Peak sequence. Hill 6975, Raker Peak, Fairfield Peak, Hat Mountain and Cinder Cone are vents the Twin Lakes sequence. Painted Dunes and Fantastic Lava Beds originate from Cinder Cone. Prospect Peak is a regional calc-alkaline andesite and basaltic andesite volcano. Mount Conard forms the southeast rim of the eroded amphitheater of Brokeoff Volcano.
What are the oldest volcanic rocks in Lassen?
The oldest volcanic rocks in the Lassen vicinity comprise the Latour and Yana volcanic centers. Rocks of the Latour Volcanic Center (>3 Ma) are present northwest of Lassen Volcanic National Park, whereas rocks of the Yana Volcanic Center (~3.4–2.4 Ma) dominate the area southwest of Lake Almanor. These two volcanic centers are important as the primary sources of the Tuscan Formation (~3.5 to 2.5 My old), a broad volcanic and volcaniclastic wedge of fragmental material emplaced on west slope of the southernmost Cascade Range. The Tuscan Formation consists primarily of volcanic debris flows (lahars), conglomerate, sandstone, and siltstone, with minor silicic ash -flow and airfall tuffs and several basaltic to andesitic lava flows.
What are the two sequences of the Brokeoff Volcano?
The stratigraphy of Brokeoff Volcano is described by Clynne and Muffler (USGS Scientific Investigations Map 2899) as two sequences of deposits: the Mill Canyon sequence and the Diller sequence.
What is the Tuscan Formation?
The Tuscan Formation consists primarily of volcanic debris flows (lahars), conglomerate, sandstone, and siltstone, with minor silicic ash -flow and airfall tuffs and several basaltic to andesitic lava flows .
How many ka are there in Lassen Volcanic National Park?
These include the most prominent young volcanic features in in Lassen Volcanic National Park: Lassen Peak (27 ka) and Chaos Crags (1.1 ka), as well as the products of 5 older eruptions.
What is the Lassen Peak Trail?
Lassen Peak Trail features continuous, panoramic views. Lassen Peak Trail climbs to the summit of one of the largest plug dome volcanoes in the world. Beginning at the Lassen Peak parking area, the trail climbs through twisted mountain hemlock and whitebark pine trees on sand-like cinders.
Why is it important to stay on the trail?
You can enjoy and help preserve one of the park’s oldest and most popular trails by simply staying on it. Traveling off-trail causes damage . Your footsteps can push rocks onto the trail, create pathways for water erosion, and undermine the supporting slope. See hikers straying from the trail? Speak up! A courteous reminder about why it’s important to stay on the trail is usually enough. If not, please report destructive behavior to a park ranger.
Can you climb Lassen Peak?
You can climb Lassen Peak at any age as long as you are able to do so. Not recomended for small children of persons with health concerns.
Can hiking at high elevation cause medical problems?
Hiking at High Elevation can aggravate pre-existing medical conditions. Know the effects of altitude. Carry plenty of water, take breaks often, and do not exceed your abilities.
Is Lassen Peak in snow?
Lassen Peak is covered with many feet of snow in the winter. There is also avalanche danger. It takes special equipment and training to ascend the mountain in winter.
Is there shade on Lassen Peak?
Sun Exposure is considerable on Lassen Peak Trail. Tree shade may be found in the first mile after which limited shade is available.
Overview
Eruptive history
Between 385,000 and 315,000 years ago, volcanism at the Lassen center shifted from andesitic stratovolcano construction to production of dacite domes. Over the past 300,000 years, the Lassen Peak area has produced more than 30 lava domes, Lassen Peak being the largest. These lava domes formed as a result of rising lava that was pushed up but was too viscous to escape its sourc…
Geography
Located in Lassen Volcanic National Park, Lassen Peak lies in Shasta County, 55 mi (89 km) east of the city of Redding, in the U.S. state of California. Lassen Peak and the rest of the National Park area are surrounded by the Lassen National Forest, which has an area of 1,200,000 acres (4,900 km ). Nearby towns include Mineral in Tehama County and Viola in Shasta County.
Ecology
Lassen Peak supports a variety of flora that include mountain hemlock, whitebark pine, and alpine wildflowers. Mountain hemlocks generally only reach an elevation of 9,200 ft (2,800 m), while whitebark pines reach up to 10,000 ft (3,000 m). Throughout the national park, forests can be found featuring red fir, mountain alder, western white pine, white fir, lodgepole pine, Jeffrey pine, ponderosa pine, incense cedar, juniper, and live oak. Other plants found in the Lassen Peak are…
Geology
Lassen Peak lies near the southern end of the Cascade Volcanic Arc, at the western edge of the Basin and Range Province. Like other Cascade volcanoes, it was fed by magma chambers produced by the subduction of the oceanic Juan de Fuca tectonic plate under the western edge of the continental North American tectonic plate. The region is also affected geologically by the Cascadia subduct…
Human history
The areas surrounding Lassen Peak, especially to its east, south, and southeast, represented a meeting ground for Maidu, Yana, Yahi, and Atsugewi Native Americans. The volcano is known among some native populations as Amblu Kai, which means "Mountain Ripped Apart" or "Fire Mountain," and as Kom Yamani, which means "Snow Mountain," among the Mountain Maidu. Bec…
Recreation
The Lassen Volcanic National Park is visited by more than 350,000 people every year. Incorporating more than 150 mi (240 km) of hiking trails, it is visited by people looking to hike or backpack during the summers. Popular winter activities include snowshoeing and backcountry skiing. As the second-tallest volcano in Northern California, trailing only Mount Shasta, Lassen Peak is freq…
See also
• List of highest points in California by county
• List of Ultras of the United States
• List of volcanoes in the United States
Yana and Latour Volcanic Centers and The Tuscan Formation
- The oldest volcanic rocks in the Lassen vicinity comprise the Latour and Yana volcanic centers. Rocks of the Latour Volcanic Center (>3 Ma) are present northwest of Lassen Volcanic National Park, whereas rocks of the Yana Volcanic Center (~3.4–2.4 Ma) dominate the area southwest of Lake Almanor. These two volcanic centers are important as the prima...
Dittmar Volcanic Center
- The Dittmar Volcanic Center (2.4–1.4 Ma) lies at the NW end of the Lake Almanor Graben. Deposits of the Dittmar Volcanic Center are grouped into 3 stratigraphic stages: Stage 1, early growth of the composite cone (1.6 to 2.3 Ma) with thin lava flows and intermixed layers (interbedded) of air-fall and volcanoclastic deposits; Stage 2, later growth of the composite cone …
Maidu Volcanic Center
- The Maidu Volcanic Center (2.4–1.2 Ma) formed at a similar time as the Dittmar Volcanic Center and is located southwest of Lassen Volcanic National Park where it overlies the Tuscan Formation and rocks of the Yana Volcanic Center. Like the Dittmar, it consists of three stratigraphic stages: Stage 1, early composite cone growth with thin lava flows and fragmental deposits erupted from …
Lassen Volcanic Center
- The major stratigraphic divisions of the Lassen Volcanic Center are designated as the Rockland caldera complex, Brokeoff Volcano, and the Lassen domefield. These eruptive stages are connected periods volcanism distinctly different from one another but linked by a common magmatic system. Rockland caldera complex The Rockland caldera complex consists of the Ro…