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Research about Lassen Volcanic National Park

Source-linked reports with geographic coverage including Lassen Volcanic National Park.

13 recordsLinked to original sources
USGS2024

Cosmogenic 21Ne exposure ages on late Pleistocene moraines in Lassen Volcanic National Park, California, USA

We report new cosmogenic 21 Ne in quartz exposure ages from 18 samples on three distinct moraines deposited in the Lost Creek drainage, approximately 3–7 km down-valley from Lassen Peak in Lassen Volcanic National Park. Although measuring 21 Ne in quartz is generally straightforward, accurate 21 Ne exposure dating of deposits of late Pleistocene is rarely possible due to the significant quantities of non-cosmogenic 21 Ne present in most lithologies. Young quartz-bearing volcanic rocks have been observed to be an exception. We take advantage of moraine boulders sourced from the ∼ 28 ka dacite of Lassen Peak to generate a chronology of alpine deglaciation in Lassen Volcanic National Park. Ages from three distinct moraines are in stratigraphic order at 22.1 ± 3.8, 20.2 ± 2.4, and 15.3 ± 3.8 ka and generally agree with other terminal and some recessional moraine ages across the Cascade Range and Sierra Nevada of the western United States. To date, these are among the youngest surfaces ever dated using cosmogenic 21 Ne and provide a cost-effective proof-of-concept approach to dating moraines where applicable.

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USGS2023

Forest structure and residual tree growth at the Northwest Gateway project area, Lassen Volcanic National Park, California

Mechanical thinning and prescribed fire are common mitigation treatments to reduce fire hazards. However, these treatments are infrequently applied together within national parks. The Northwest Gateway project at Lassen Volcanic National Park is an exception to this pattern. Various thinning prescriptions were applied to the project area in 2014, with a subset of the area prescribed burned in 2018 and 2019. To determine responses to these treatments, we analyzed forest structure and fuels data across a network of long-term monitoring plots measured before treatments and in multiple years following treatments. Additionally, we assessed patterns in individual tree growth from cores taken from 101 individual yellow pines (ponderosa pine, Pinus ponderosa Douglas ex Lawson & C. Lawson, and Jeffery pine, P. jeffreyi Grev. & Balf.) within the project unit. Basal area and stem density were reduced following thinning treatments for pole-sized (≤15-centimeter diameter at base height) and overstory trees (>15-centimeter diameter at base height), with sharper reductions in pole-sized trees. Proportional change in live basal area after thinning was highest for pole-size Abies , with more than 80-percent basal area and stem density removed on average. There were large reductions in pole-sized Pinus and Populus . However, Populus trees were not targeted for removal, suggesting that these trees died via other mechanisms. Thinning treatments also resulted in reductions in stand density index values and in surface fuel loading when followed by prescribed fire, particularly for small fuels size classes (such as litter/duff, 1-hour, and 10-hour fuels). Growth of individual residual yellow pine, measured in terms of annual basal area increment, indicated a strong growth release in the years following thinning treatments. Taken together, these results indicate that forest restoration treatments at the Northwest Gateway project area were effective at reducing stand density and encouraging growth of residual Pinus . Interestingly, our results also indicated that although thinning followed by prescribed fire was most effective at reducing surface fuel loads, harvest techniques such as whole tree yarding may effectively reduce the accumulation of post-treatment residual fuels, especially when combined with hand piling and other targeted treatments.

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USGS2022

Long-term effects of prescribed fire on large tree growth in mixed conifer forests at Lassen Volcanic National Park, California

Prescribed fire in dry coniferous forests of the western U.S. is used to reduce fire hazards. How large, old trees respond to these treatments is an important management consideration. Growth is a key indicator of residual tree condition, which can be predictive of mortality and response to future disturbance. Using a combination of long-term plot records and dendrochronological samples, we analyzed the effects of prescribed fire treatments from the early 1990 s on forest structure and individual tree growth in mixed-conifer forests of Lassen Volcanic National Park in northern California. Prescribed fire reduced stand live tree basal area and stem density at our sites up to 10 years following fire. Within two prescribed fire burn units and two adjacent unburned stands, we analyzed tree cores from 136 large (mean stem diameter > 70 cm) yellow pine ( Pinus jeffreyi and P. ponderosa ) and 136 large (mean stem diameter > 50 cm) white fir ( Abies concolor ). After accounting for annual precipitation, basal area increment for individual trees initially declined up to < 3 years post-fire for white fir and > 10 years post-fire for yellow pine, presumably in response to tree injuries. Growth improved for both species at a site that was burned twice, particularly for white fir. Recent average basal area increment was positively related to crown ratio and negatively associated with an index of local competition. Our findings suggest that forest management, such as prescribed fire and mechanical thinning, may be beneficial in terms of maintaining or improving tree growth among large residual trees. However, managers may want to balance the benefits of these treatments against inadvertent injury and mortality of large trees.

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USGS2016

The Lassen hydrothermal system

The active Lassen hydrothermal system includes a central vapor-dominated zone or zones beneath the Lassen highlands underlain by ~240 &deg;C high-chloride waters that discharge at lower elevations. It is the best-exposed and largest hydrothermal system in the Cascade Range, discharging 41 &plusmn; 10 kg/s of steam (~115 MW) and 23 &plusmn; 2 kg/s of high-chloride waters (~27 MW). The Lassen system accounts for a full 1/3 of the total high-temperature hydrothermal heat discharge in the U.S. Cascades (140/400 MW). Hydrothermal heat discharge of ~140 MW can be supported by crystallization and cooling of silicic magma at a rate of ~2400 km 3 /Ma, and the ongoing rates of heat and magmatic CO 2 discharge are broadly consistent with a petrologic model for basalt-driven magmatic evolution. The clustering of observed seismicity at ~4&ndash;5 km depth may define zones of thermal cracking where the hydrothermal system mines heat from near-plastic rock. If so, the combined areal extent of the primary heat-transfer zones is ~5 km 2 , the average conductive heat flux over that area is >25 W/m 2 , and the conductive-boundary length <50 m. Observational records of hydrothermal discharge are likely too short to document long-term transients, whether they are intrinsic to the system or owe to various geologic events such as the eruption of Lassen Peak at 27 ka, deglaciation beginning ~18 ka, the eruptions of Chaos Crags at 1.1 ka, or the minor 1914&ndash;1917 eruption at the summit of Lassen Peak. However, there is a rich record of intermittent hydrothermal measurement over the past several decades and more-frequent measurement 2009&ndash;present. These data reveal sensitivity to climate and weather conditions, seasonal variability that owes to interaction with the shallow hydrologic system, and a transient 1.5- to twofold increase in high-chloride discharge in response to an earthquake swarm in mid-November 2014.

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USGS2015

Geologic field-trip guide to Lassen Volcanic National Park and vicinity, California

This geologic field-trip guide provides an overview of Quaternary volcanism in and around Lassen Volcanic National Park in northern California. The guide begins with a comprehensive overview of the geologic framework and the stratigraphic terminology of the Lassen region, based primarily on the &ldquo;Geologic map of Lassen Volcanic National Park and vicinity&rdquo; (Clynne and Muffler, 2010). The geologic overview is then followed by detailed road logs describing the volcanic features that can readily be seen in the park and its periphery. Twenty-one designated stops provide detailed explanations of important volcanic features. The guide also includes mileage logs along the highways leading into the park from the major nearby communities. The field-trip guide is intended to be a flexible document that can be adapted to the needs of a visitor approaching the park from any direction.

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USGS2010

Analyses of gas, steam and water samples collected in and around Lassen Volcanic National Park, California, 1975–2002

This report contains physical and chemical data from gas, steam, and water samples collected between July 1975 and September 2002 from locations in and around Lassen Volcanic National Park, California. Data are compiled as tables in Excel spreadsheets and are organized by locale. Most data are keyed to 1 of 107 site codes that are shown on local- and regional-scale maps. Brief descriptions of terminology, sampling, and analytical methods are provided.

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USGS2010

Geologic map of Lassen Volcanic National Park and vicinity, California

The geologic map of Lassen Volcanic National Park (LVNP) and vicinity encompasses 1,905 km 2 at the south end of the Cascade Range in Shasta, Lassen, Tehama, and Plumas Counties, northeastern California (fig. 1, sheet 3). The park includes 430 km 2 of scenic volcanic features, glacially sculpted terrain, and the most spectacular array of thermal features in the Cascade Range. Interest in preserving the scenic wonders of the Lassen area as a national park arose in the early 1900s to protect it from commercial development and led to the establishment in 1907 of two small national monuments centered on Lassen Peak and Cinder Cone. The eruptions of Lassen Peak in 1914-15 were the first in the Cascade Range since widespread settling of the West in the late 1800s. Through the printed media, the eruptions aroused considerable public interest and inspired renewed efforts, which had languished since 1907, to establish a national park. In 1916, Lassen Volcanic National Park was established by combining the areas of the previously established national monuments and adjacent lands. The southernmost Cascade Range is bounded on the west by the Sacramento Valley and the Klamath Mountains, on the south by the Sierra Nevada, and on the east by the Basin and Range geologic provinces. Most of the map area is underlain by middle to late Pleistocene volcanic rocks; Holocene, early Pleistocene, and late Pliocene volcanic rocks (<3.5 m.y.) are less common. Paleozoic and Mesozoic rocks are inferred to underlie the volcanic deposits (Jachens and Saltus, 1983), but the nearest exposures of pre-Tertiary rocks are 15 km to the south, 9 km to the southwest, and 12 km to the west. Diller (1895) recognized the young volcanic geology and produced the first geologic map of the Lassen area. The map (sheet 1) builds on and extends geologic mapping by Williams (1932), Macdonald (1963, 1964, 1965), and Wilson (1961). The Lassen Peak area mapped by Christiansen and others (2002) and published in greater detail (1:24,000) was modified for inclusion here. Figure 2 (sheet 3) shows the mapping credit for previous work; figure 3 (sheet 3) shows locations discussed throughout the text. A CD-ROM entitled Database for the Geologic Map of Lassen Volcanic National Park and Vicinity, California accompanies the printed map (Muffler and others, 2010). The CD-ROM contains ESRI compatible geographic information system data files used to create the 1:50,000-scale geologic map, both geologic and topographic data and their associated metadata files, and printable versions of the geologic map and pamphlet as PDF formatted files. The 1:50,000-scale geologic map was compiled from 1:24,000-scale geologic maps of individual quadrangles that are also included in the CD-ROM. It also contains ancillary data that support the map including locations of rock samples selected for chemical analysis (Clynne and others, 2008) and radiometric dating, photographs of geologic features, and links to related data or web sites. Data contained in the CD-ROM are also available on this Web site. The southernmost Cascade Range consists of a regional platform of basalt and basaltic andesite, with subordinate andesite and sparse dacite. Nested within these regional rocks are 'volcanic centers', defined as large, long-lived, composite, calc-alkaline edifices erupting the full range of compositions from basalt to rhyolite, but dominated by andesite and dacite. Volcanic centers are produced by the focusing of basaltic flux from the mantle and resultant enhanced interaction of mafic magma with the crust. Collectively, volcanic centers mark the axis of the southernmost Cascade Range. The map area includes the entire Lassen Volcanic Center, parts of three older volcanic centers (Maidu, Dittmar, and Latour), and the products of regional volcanism (fig. 4, sheet 3). Terminology used for subdivision of the Lassen Volcanic Center has been modified from Clynne (1984, 1990).

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USGS2009

Multiple dendrochronological responses to the eruption of Cinder Cone, Lassen Volcanic National Park, California

Two dendrochronological properties – ring width and ring chemistry – were investigated in trees near Cinder Cone in Lassen Volcanic National Park, northeastern California, for the purpose of re-evaluating the date of its eruption. Cinder Cone is thought to have erupted in AD 1666 based on ring-width evidence, but interpreting ring-width changes alone is not straightforward because many forest disturbances can cause changes in ring width. Old Jeffrey pines growing in Cinder Cone tephra and elsewhere for control comparison were sampled. Trees growing in tephra show synchronous ring-width changes at AD 1666, but this ring-width signal could be considered ambiguous for dating the eruption because changes in ring width can be caused by other events. Trees growing in tephra also show changes in ring phosphorus, sulfur, and sodium during the late 1660s, but inter-tree variability in dendrochemical signals makes dating the eruption from ring chemistry alone difficult. The combination of dendrochemistry and ring-width signals improves confidence in dating the eruption of Cinder Cone over the analysis of just one ring-growth property. These results are similar to another case study using dendrochronology of ring width and ring chemistry at Parícutin, Michoacán, Mexico, a cinder cone that erupted beginning in 1943. In both cases, combining analysis with ring width and ring chemistry improved confidence in the dendro-dating of the eruptions.

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USGS2008

Radiocarbon dates from volcanic deposits of the Chaos Craigs and Cinder Cone eruptive sequences and other deposits, Lassen Volcanic National Park and vicinity, California

This contribution reports radiocarbon ages obtained from charcoal, wood and other samples collected between 1979 and 2001 in Lassen Volcanic National Park and vicinity and a few samples from other nearby localities. Most of the samples are from the Chaos Crags and Cinder Cone eruptive sequences. Brief summaries are given of the Chaos Crags and Cinder Cone eruptive sequences.

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USGS1994

Measurements of heat and mass flow from thermal areas in Lassen Volcanic National Park, California, 1984-93

Rates of heat loss from eight steam-heated thermal areas and one conductively heated thermal area in Lassen Volcanic National Park have been determined from measurements made during the period 1984-93. Total heat discharge at the steam-heated areas is assumed proportional to the rate of steam upflow from underlying reservoirs. The dominant mode of heat loss differs among the areas studied; at Bumpass Hell and Boiling Springs Lake evaporation from water surfaces dominates, whereas at Devils Kitchen and Little Hot Springs Valley most of the heat is lost by advection in streams. Heat loss from furnaroles, which discharge at temperatures of 93 157°C depending on the area, accounts for less than 30 percent of the total heat loss for all but the smallest thermal areas. Estimates of total heat loss from the eight steam-heated areas range from about 30 megawatts at Bumpass Hell and Boiling Springs Lake to less than 2 megawatts at Terminal Geyser, Pilot Pinnacle and Lassen Peak, and total about 120 megawatts. The corresponding rate of steam upflow required to supply this total heat loss is approximately 40 kilograms per second, with about half providing heat input to the five thermal areas situated on the flanks of Lassen Peak and the remainder supplying heat to thermal areas situated to the southeast of Lassen Peak along or near Hot Springs Creek. For the most part, heat-loss measurements were made during late summer and fall when streamflows were relatively low. At each thermal area, rates of streamflow and advective heat loss are greatest in the spring and early summer, reflecting depletion of stored heat by infiltrating cold water. Such seasonal variations, along with variations due to errors in our heat-loss determinations, result in uncertainties of approximately ± 20 percent in our estimates of total heat loss and steam upflow at all the Park's thermal areas.

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