Discovery of Mazama ash in Saskatchewan, Canada

1970 ◽  
Vol 7 (6) ◽  
pp. 1579-1583 ◽  
Author(s):  
Peter P. David
Keyword(s):  
Refractive Index ◽  
Chemical Composition ◽  
Volcanic Glass ◽  
River Valley ◽  
The South ◽  
Sedimentary Environments ◽  
Ash Layer ◽  
South Saskatchewan River ◽  
Eolian Sediments ◽  
Eolian Deposits

The first known Mazama ash occurrence in Saskatchewan was discovered in eolian sediments at the top of the bluffs on the South Saskatchewan River valley 20 miles (~32 km) west of Leader, Saskatchewan. The chemical composition and the refractive index of the volcanic glass serve for the definite identification of the Mazama ash. The ash layer is a useful horizon marker in the eolian sediments, for it represents a time-break at 6 600 years ago. It is suggested that eolian deposits in similar sedimentary environments be examined for other occurrences of the Mazama ash.

First evidence of a distal early Holocene ash layer in Eastern Mediterranean deep-sea sediments derived from the anatolian volcanic province

2010 ◽  
Vol 73 (3) ◽  
pp. 497-506 ◽  
Author(s):  
Y. Hamann ◽  
S. Wulf ◽  
O. Ersoy ◽  
W. Ehrmann ◽  
E. Aydar ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Eastern Mediterranean ◽  
Eastern Mediterranean Region ◽  
Volcanic Glass ◽  
Volcanic Field ◽  
Early Holocene ◽  
The South ◽  
Volcanic Province ◽  
Levantine Sea ◽  
Ash Layer

A hitherto unknown distal volcanic ash layer has been detected in a sediment core recovered from the southeastern Levantine Sea (Eastern Mediterranean Sea). Radiometric, stratigraphic and sedimentological data show that the tephra, here termed as S1 tephra, was deposited between 8970 and 8690 cal yr BP. The high-silica rhyolitic composition excludes an origin from any known eruptions of the Italian, Aegean or Arabian volcanic provinces but suggests a prevailing Central Anatolian provenance. We compare the S1 tephra with proximal to medial-distal tephra deposits from well-known Mediterranean ash layers and ash fall deposits from the Central Anatolian volcanic field using electron probe microanalyses on volcanic glass shards and morphological analyses on ash particles. We postulate a correlation with the Early Holocene "Dikkartın" dome eruption of Erciyes Dağ volcano (Cappadocia, Turkey). So far, no tephra of the Central Anatolian volcanic province has been detected in marine sediment archives in the Eastern Mediterranean region. The occurrence of the S1 tephra in the south-eastern part of the Levantine Sea indicates a wide dispersal of pyroclastic material from Erciyes Da? more than 600 km to the south and is therefore an important tephrostratigraphical marker in sediments of the easternmost Mediterranean Sea and the adjacent hinterland.

The Stampede tephra: a middle Pleistocene marker bed in glacial and eolian deposits of central Alaska

1991 ◽  
Vol 28 (7) ◽  
pp. 991-1002 ◽  
Author(s):  
James E. Begét ◽  
Mary Keskinen
Keyword(s):  
River Valley ◽  
Middle Pleistocene ◽  
Alaska Range ◽  
Multiple Fault ◽  
Eolian Sediments ◽  
Eolian Deposits ◽  
Quaternary Glaciations

A deformed block of silt incorporated in a push moraine of the Lignite Creek drift of the Nenana River valley in central Alaska contains the 10 cm thick Stampede tephra. The silt block and tephra are folded, sheared, and cut by multiple fault planes and appear to have been entrained by a glacier and deformed by glaciotectonic processes while frozen. The Stampede tephra is also found in a paleosol preserved within a sequence of eolian sediments near the Tanana River some 175 km to the northeast, allowing direct tephrochronologic correlations between the depositional record of Quaternary glaciations in the Alaska Range and eolian sediments in unglaciated central Alaska. The Lignite Creek drift predates deposits of the late Wisconsin Riley Creek and penultimate Healy glaciations but postdates the Stampede tephra, indicating that it dates to the middle Quaternary, and is not part of the Tertiary Nenana Gravel Formation.

A Note on the Most Recent Ichthyosaur Known: an Isolated Coracoid from the Upper Campanian of Saskatchewan (Reptilia, Ichthyosauria)

1973 ◽  
Vol 10 (8) ◽  
pp. 1346-1349
Author(s):  
C. McGowan
Keyword(s):  
River Valley ◽  
The South ◽  
South Saskatchewan River ◽  
Upper Campanian

The geologically youngest ichthyosaur specimen is described: an isolated, partial coracoid from the Bearpaw Formation of the South Saskatchewan river valley (Upper Campanian) near Stewart Valley, Saskatchewan. The final extinction of the Ichthyosauria is briefly discussed, and the possibility that it may not have been brought about by competition from the mosasaurs is examined.

Composition and properties of horseradish (Armoracia rusticana), as one of the representatives of the essential oil culture in Siberia

2020 ◽  
Author(s):  
G.A. Demidenko G.A. ◽  
Keyword(s):  
Chemical Composition ◽  
Essential Oil ◽  
The South ◽  
Armoracia Rusticana

The article presents an analysis of the chemical composition and properties of horseradish (Armoracia rusticana), as one of the representatives of the essential oil culture in the Siberian conditions in the South of the Krasnoyarsk territory.

Sign in / Sign up

Export Citation Format

Share Document