The Bishop Ash Bed, a Pleistocene Marker Bed in the Western United States

Izett, G. A.; Wilcox, Ray E.; Powers, Howard A.; Desborough, George A.

doi:10.1016/0033-5894(70)90014-1

Cited by 100 publications

(28 citation statements)

References 12 publications

(2 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The Long Valley Caldera was created catastrophically around 760,000 years ago in a paroxysmal volcanic eruption which spread ash over much of the western United States (Fig. 1, inset, after Izelt et al 1970). The cataclysmic eruption left thick deposits of the Bishop Tuff up to *250 m thick in the Long Valley area (Bailey 1976), and the caldera remains the dominant physiographic feature in the area today.…”

Section: Geologic Backgroundmentioning

confidence: 95%

See 1 more Smart Citation

Comparison of risk from pyroclastic density current hazards to critical infrastructure in Mammoth Lakes, California, USA, from a new Inyo craters rhyolite dike eruption versus a dacitic dome eruption on Mammoth Mountain

et al. 2009

View full text Add to dashboard Cite

Renewed volcanic activity near Mammoth Lakes, California, in the form of dome-collapse pyroclastic density currents (PDCs) from either a new eruption at Mammoth Mountain or the Inyo craters would pose a significant hazard to critical infrastructure there. This paper compares the risk from PDC impact hazards upon selected critical infrastructure from: (1) a 100 m tall dacite dome on Mammoth Mountain and (2) three 200 m tall rhyolite domes at the southern end of the Inyo craters. For each scenario, maximum estimated dynamic pressure and velocity from two PDC volumes (10 6 and 10 7 m 3 ) are modeled with the EXPLORIS PDC software (Toyos et al. Nat Hazards 41(1):99-112, 2007). Risk to critical infrastructure from Mammoth Mountain PDCs would be much greater than the Inyo PDCs because of both location and the greater kinetic energy of the Mammoth PDC material, providing comparative insight to planners should a real eruption at one location or the other be forthcoming.

show abstract

Section: Geologic Backgroundmentioning

confidence: 95%

“…The inset gives the distribution of the ash from the 760,000 y.b.p. caldera-forming eruption of the Bishop Tuff, after Izelt et al 1970 (Hildreth 2004;Bailey 1989). After the youngest moat rhyolite, the next eruptive activity in the LVC area was the emplacement of the silicic Mammoth Mountain stratovolcano.…”

Section: Geologic Backgroundmentioning

confidence: 98%

Comparison of risk from pyroclastic density current hazards to critical infrastructure in Mammoth Lakes, California, USA, from a new Inyo craters rhyolite dike eruption versus a dacitic dome eruption on Mammoth Mountain

et al. 2009

View full text Add to dashboard Cite

show abstract

“…760 ka Bishop ash from Long Valley Caldera (Izett et al, 1970) led to the subsequent deposition of 5 m of pure to impure tephra in Owens Lake ( Fig. 1; Table 1), possibly over a geologically instantaneous period of time.…”

Section: Tephramentioning

confidence: 98%

Stratigraphy, lithologies, and sedimentary structures of Owens Lake core OL-92

Smith¹

1997

An 800,000-Year Paleoclimatic Record From Core OL-92, Owens Lake, Southeast California

View full text Add to dashboard Cite

Owens Lake, a now-dry lake in southeastern California immediately east of the southern Sierra Nevada, was the site of a coring project designed to obtain a long paleoclimatic record. During the ensuing study, lacustrine deposits were recovered by the 323 m long core designated "OL-92." The presence of the Bishop ash (ca. 760 ka) and the Matuyama-Brunhes paleomagnetic reversal (ca. 780 ka) near the base of core OL-92 shows that this core represents about 800 k.y. of deposition in Owens Lake.The sediments are dominantly lacustrine clay, silt, and fine sand, although some intervals contain as much as 40 wt % CaCO 3 . The lowest ~57 m of recovered sediments is mostly silt or clay, but several sand beds are present; the overlying ~60 m of sediment is similar, but its sand content is more dispersed. Together, these two units are composed of ~70 wt % silt and clay and ~30 wt % sand, suggesting deposition in lakes that fluctuated between moderately deep and shallow. Overlying them is ~201 m of sediments that were mostly deposited in deep water; they consist predominantly of silt and clay but include two thin, coarse-sand beds. An oolite bed forms the upper ~4 m of natural deposits, and an anthropogenic salt bed, >2 m thick, forms much of the present surface. In addition to the Bishop ash, several much thinner tephra layers are also present.About 70% of the clastic-sediment units are massive, some clearly because of bioturbation; other units display a thin bedding defined by changes in color or grain size. Rhythmic bedding, observed in numerous segments <1 m thick, seems to represent cyclical events ~100 yr long. Thin color bands caused by the chemical alteration of sediments on each side of hairline fractures create irregular subvertical veins. Clastic dikes, as much as ~2 cm wide and ~75 cm long, characterize some zones. Bioturbation structures, sand pods, ice-rafted(?) granules, small faults, minor discontinuities, and possible turbidity-current structures are also present.Lithologic variations, in combination with other evidence, indicate that from ca. 810-645 ka, Owens was most commonly a moderately deep fresh-water lake; from ca. 645-450 ka, it was more commonly a shallow-but still fresh-water-lake; from ca. 450-5 ka, it was almost continuously a deep, mostly fresh-water lake; and after ca. 5 ka, it was a shallow, moderately saline lake. Other variations in the sediments and their contents, however, indicate additional cycles of average lake-overflow volumes that are not reflected by sediment-size changes.

show abstract

“…The Lava Creek tuff (Izett, 1981 ), previously known as the pearlette ash Type 0 (Izett et al, 1970) and dated at 0.616 Ma, provide a widespread stratigraphic marker for the base of this period. The Hebgen Lake and Grayling Arm tills (Richmond, 1986) are older and younger than 0.482Ma respectively and are correlated with this event.…”

Section: The Aftonian Warm Eventmentioning

confidence: 99%

Chronostratigraphy of glaciations and permafrost episodes in the Cordillera of western North America

Harris

1994

Progress in Physical Geography: Earth and Environment

View full text Add to dashboard Cite

Glaciations in the Cordillera of western North America began during the Late Miocene in the St Elias Range and coastal ranges near Anchorage, Alaska. Radiometric dating of the tephra and lava flows intercalated in the succession of older tills, loesses and outwash deposits permits the reconstruction of the probable early glacial sequence along the Cordillera. No one site shows the complete sequence, but the available data suggest synchroneity of the major glacial events throughout the region.The first evidence for cold conditions at low elevations at midlatitudes is from 3.5 Ma BP. By 2.8 Ma, alpine glaciations may have occurred in the Sierra Nevada and ice wedges had formed in bedrock near Fairbanks, Alaska. Three more major glaciations complete with contemporary periglacial and permafrost landforms had occurred by 1.65 Ma, while at least six more major cold events can be recognized during the Quaternary period. Once again, expansion of permafrost conditions occurred during each event and forms an integral part of the evidence for climatic change.

show abstract

The Bishop Ash Bed, a Pleistocene Marker Bed in the Western United States

Cited by 100 publications

References 12 publications

Comparison of risk from pyroclastic density current hazards to critical infrastructure in Mammoth Lakes, California, USA, from a new Inyo craters rhyolite dike eruption versus a dacitic dome eruption on Mammoth Mountain

Comparison of risk from pyroclastic density current hazards to critical infrastructure in Mammoth Lakes, California, USA, from a new Inyo craters rhyolite dike eruption versus a dacitic dome eruption on Mammoth Mountain

Stratigraphy, lithologies, and sedimentary structures of Owens Lake core OL-92

Chronostratigraphy of glaciations and permafrost episodes in the Cordillera of western North America

Contact Info

Product

Resources

About