Age, distribution, and stratigraphy of Glacier Peak tephra in eastern Washington and western Montana, United States

1993 ◽  
Vol 30 (3) ◽  
pp. 535-552 ◽  
Author(s):  
Franklin F. Foit Jr. ◽  
Peter J. Mehringer Jr. ◽  
John C. Sheppard
Keyword(s):  
Radiocarbon Dating ◽  
Age Distribution ◽  
Analytical Techniques ◽  
Western Montana ◽  
East Central ◽  
Tephra Layers ◽  
Tephra Stratigraphy ◽  
Mineral Compositions ◽  
Eastern Washington ◽  
Lake Deposits

Tephra layers from Williams Lake Fen, Wildcat Lake, and East Wenatchee, Washington, and Kearns Basin, Lost Trail Pass, Sheep Mountain Bog, and Marys Frog Pond, Montana, were analyzed by electron microprobe (EMP), and associated lake deposits were radiocarbon dated. Though the tephra layers can be grouped by source (Glacier Peak, Mount Mazama, Mount Saint Helens, and unknown source), statistical analyses of both glass and mineral compositions show that finer distinctions within a group (for example, Glacier Peak B, M, and G) cannot be made on the basis of chemical data obtained using conventional EMP techniques. It appears that more-sensitive analytical techniques may be needed to discriminate among the Glacier Peak tephras. Tephra stratigraphy at the various sites reveals a potentially greater complexity in Glacier Peak tephra distributions and ages than was anticipated. All sites, except Sheep Mountain Bog and East Wenatchee, contained two Glacier Peak tephras. Taken as a whole the Glacier Peak tephra layers may record closely timed, multiple eruptions with restricted ash falls as well as widespread tephra from large eruptions. Radiocarbon dating generally confirms a 14C age of 11 200 years BP for a distal Glacier Peak couplet(s) that occurs, stratigraphically, both above and below Mount Saint Helens J tephra in east-central Washington.

Compositional variability of Glacier Peak tephra and its stratigraphic significance

1978 ◽  
Vol 15 (10) ◽  
pp. 1554-1567 ◽  
Author(s):  
J. A. Westgate ◽  
M. E. Evans
Keyword(s):  
National Park ◽  
Western Montana ◽  
Violent Event ◽  
Age Composition ◽  
Relative Age ◽  
Palaeomagnetic Data ◽  
Tephra Layers ◽  
Compositional Variability ◽  
Northern Idaho ◽  
Eastern Washington

Glacier Peak Volcano erupted many times during the period from ~11 000 to ~13 000 years ago and produced at least Three widespread tephra layers that serve as valuable stratigraphic markers in northwestern United States and the adjacent plains of southwestern Canada. Each of these units can be recognized by their stratigraphic, petrographic, and chemical attributes.Tephra was shed over eastern Washington, northern Idaho, western Montana, and southernmost Alberta during each of the eruptions responsible for the older two units; the other layer was deposited during the youngest and most violent event that directed tephra to the southeast as far as Yellowstone National Park, ~950 km from the volcano.Chemical data on glass, hornblende, hypersthene, feldspar, magnetite, and ilmenite show a systematic and unidirectional trend in tephra composition with age; earlier eruptions produced slightly more acidic tephra. This age–composition relationship is confirmed by palaeomagnetic data obtained from 116 specimens collected from two 5 m thick sections. It should therefore be possible to determine the relative age of Glacier Peak tephra samples by their composition alone.The chronology of the Glacier Peak eruptive sequence is still poorly understood. This is especially true of the oldest unit which has so far only been found in southeastern Alberta. Proximal occurrences should be sought in the bogs of eastern Washington where prospects of preservation and age definition are optimised.

scholarly journals AMS Radiocarbon Dating of Holocene Tephra Layers on Ulleung Island, South Korea

Radiocarbon ◽  
2010 ◽  
Vol 52 (3) ◽  
pp. 1465-1470 ◽  
Author(s):  
Mitsuru Okuno ◽  
Miki Shiihara ◽  
Masayuki Torii ◽  
Toshio Nakamura ◽  
Kyu Han Kim ◽  
...  
Keyword(s):  
Radiocarbon Dating ◽  
Japan Sea ◽  
Eastern Coast ◽  
Time Interval ◽  
Data Set ◽  
Ams Radiocarbon Dating ◽  
Ulleung Island ◽  
The Japan Sea ◽  
Tephra Layers ◽  
Tephra Stratigraphy

Ulleung Island, a large stratovolcano, is located in the western part of the Japan Sea (East Sea), 130 km off the eastern coast of the Korean Peninsula. The Ulleung-Oki (U-Oki) is a widely distributed tephra in and around the Japan Sea, and has an age of 10.7 cal ka BP obtained from the Lake Suigetsu data set (central Japan). Of the 7 tephra layers (U-7 to -1) on the island, the pumiceous U-4, U-3, and U-2 tephra layers are petrochemically and petrographically similar to the U-Oki tephra. To determine the eruption ages of 3 tephra layers on Ulleung Island, we conducted radiocarbon dating for 5 soil and 2 charcoal samples. Although the soil samples have the C/N ratios from 5 to 10, the obtained 14C dates are still consistent with the tephra stratigraphy of the island. The calibrated 14C dates for the U-4, U-3, and U-2 tephras are 11 cal ka BP, 8.3 or 9 cal ka BP, and 5.6 cal ka BP, respectively, indicating that the explosive eruptions occurred in the island with a time interval of 2000 to 3000 yr during the period of the early to middle Holocene. Based on our chronology, the U-4 tephra is most likely correlated with the U-Oki tephra.

Preliminary interpretation of thrust-fault patterns in western Montana and east-central Idaho

1982 ◽  
Author(s):  
C.A. Wallace ◽  
E.T. Ruppel ◽  
J.E. Harrison ◽  
M.W. Reynolds
Keyword(s):  
Thrust Fault ◽  
Western Montana ◽  
East Central ◽  
Central Idaho

Patterns of Weed Migration in Northwestern U.S.A.

Weed Science ◽  
1988 ◽  
Vol 36 (2) ◽  
pp. 194-201 ◽  
Author(s):  
Frank Forcella ◽  
Stephen J. Harvey
Keyword(s):  
Principal Coordinate Analysis ◽  
Weed Species ◽  
Migration Patterns ◽  
East Central ◽  
The Past ◽  
The Future ◽  
Central Montana ◽  
Eastern Washington ◽  
Derived Data ◽  
Primary Pattern

Patterns of spread of 85 weed species alien to the northwestern U.S. were simulated using principal coordinate analysis on primarily herbaria-derived data. The primary pattern detected was a west-to-east migration of weeds. The point of introduction for most weeds following this pattern appeared to be near Portland, OR, an important shipping port in the past. An east-to-west migration represented a secondary pattern. The major cattle and wheat-cropping areas of east-central Montana were the apparent introduction points for weeds following this pattern. The grain and pulse region of eastern Washington represented the point of introduction of species following a third pattern of migration. These weeds subsequently spread southward to Utah and then laterally to the east and west. Historical weed migration patterns provide insight to probable points of origin and routes of currently spreading weeds as well as those that will spread in the future. Such insight may aid in the containment of future spreading weeds.

scholarly journals Olive oil from the 79 A.D. Vesuvius eruption stored at the Naples National Archaeological Museum (Italy)

2020 ◽  
Vol 4 (1) ◽  
Author(s):  
Raffaele Sacchi ◽  
Adele Cutignano ◽  
Gianluca Picariello ◽  
Antonello Paduano ◽  
Alessandro Genovese ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Olive Oil ◽  
Volatile Compounds ◽  
Radiocarbon Dating ◽  
Analytical Techniques ◽  
Mass Spectrometric ◽  
Hydroxy Fatty Acids ◽  
Glass Bottle ◽  
The World

Abstract Using a range of chromatographic, spectroscopic, and mass spectrometric analytical techniques, we characterized one of the “edible items” found at the Vesuvius archeological sites and guarded at the National Archaeological Museum of Naples (MANN) in Naples, Italy. We authenticated the specimen contained in a glass bottle (Mann-S1 sample) as originally olive oil and mapped the deep evolution throughout its 2000 years of storage. Triacylglycerols were completely hydrolyzed, while the resulting (hydroxy) fatty acids had partly condensed into rarely found estolides. A complex pattern of volatile compounds arose mainly from breakdown of oleic acid. With excellent approximation, radiocarbon dating placed the find at the time of the Plinian Mount Vesuvius eruption in 79 A.D., indicating that Mann-S1 is probably the oldest residue of olive oil in the world found in bulk amount (nearly 0.7 L).

scholarly journals Timescale for Climatic Events of Subboreal/Subatlantic Transition Recorded at the Valakupiai Site, Lithuania

Radiocarbon ◽  
2007 ◽  
Vol 49 (2) ◽  
pp. 889-897 ◽  
Author(s):  
Jacek Pawlyta ◽  
Algirdas Gaigalas ◽  
Adam Michczyński ◽  
Anna Pazdur ◽  
Aleksander Sanko
Keyword(s):  
Human Activity ◽  
Black Sea ◽  
Radiocarbon Dating ◽  
Basal Part ◽  
Oxbow Lake ◽  
The Black Sea ◽  
Mollusk Fauna ◽  
The Baltic ◽  
Lake Deposits

Oxbow lake deposits of the Neris River at the Valakupiai site in Vilnius (Lithuania) have been studied by different methods including radiocarbon dating. A timescale was attained for the development of the oxbow lake and climatic events recorded in the sediments. 14C dates obtained for 24 samples cover the range 990–6500 BP (AD 580 to 5600 BC). Medieval human activity was found in the upper part of the sediments. Mollusk fauna found in the basal part of the terrace indicate contact between people living in the Baltic and the Black Sea basins. Mean rates were calculated for erosion of the river and for accumulation during the formation of the first terrace.

Radiocarbon dating of tephra layers: recent progress in Japan

2003 ◽  
Vol 105 (1) ◽  
pp. 49-56 ◽  
Author(s):  
Mitsuru Okuno ◽  
Toshio Nakamura
Keyword(s):  
Radiocarbon Dating ◽  
Recent Progress ◽  
Tephra Layers

Clonal diversity within and among introduced populations of the apomictic vine Bryonia alba (Cucurbitaceae)

2000 ◽  
Vol 78 (11) ◽  
pp. 1469-1481 ◽  
Author(s):  
Stephen J Novak ◽  
Richard N Mack
Keyword(s):  
United States ◽  
Clonal Diversity ◽  
Western Montana ◽  
Western United States ◽  
Single Population ◽  
Multiple Introductions ◽  
Introduced Populations ◽  
Northern Utah ◽  
Northern Idaho ◽  
Eastern Washington

Bryonia alba L. (Cucurbitaceae) is a herbaceous Eurasian vine that predominantly reproduces clonally (asexually) through apomixis. We assessed the magnitude and distribution of clonal diversity within and among 23 recently established populations of B. alba in its new range in the western United States, based on the distribution of multilocus isozyme genotypes. Fifty-two unique clones were detected: 30 in the nine populations from eastern Washington and northern Idaho, and the remaining 22 in 14 populations from western Montana, northern Utah, and southern Idaho. On average, each population of B. alba was composed of 6.4 clones, and the proportion of distinguishable clones was 0.275. Multilocus diversity (D) was 0.632 and multilocus evenness (E) was 0.556. Twenty-six of 52 clones (50%) were restricted to a single population, and, on average, each clone occurred in 2.83 populations. Compared with other clonally reproducing plant species, this vine possesses moderate to high levels of clonal diversity in its new range in the western United States. This diversity appears to be a consequence of the events associated with its introduction (including multiple introductions), founder effects, and the proportion of sexual to apomictic reproduction within populations.Key words: invasive vine, apomixis, multilocus genotypes, clonal diversity and evenness, Bryonia alba, Cucurbitaceae.

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