K-Ar age determinations on tertiary volcanic rocks: 5. Siebengebirge, Siebengebirge-Graben
Item
Title (Dublin Core)
en-US
K-Ar age determinations on tertiary volcanic rocks: 5. Siebengebirge, Siebengebirge-Graben
Description (Dublin Core)
en-US
Sanidines from 16 tuffs of the first volcanic phase in the Siebengebirge and the Siebengebirge-Graben were dated by the K/Ar-method. Ages range from 24.1 (Nachtigallental) to 22.9 M.y. (core Rott). Three mineral ages from surface outcrops in the Central Siebengebirge (23.9 ± 0.5 M.y.) are statistically indistinguishable from those of the sub-surface samples Stieldorf-1, Stieldorf-2, and Rott (23.0 ± 0.5 M.y.). These ages confirm the Uppermost Oligocene biostratigraphic age of the 'Blatterkohle Rott' which is interlayered with the trachyte tuff. Sanidine and biotite mineral ages from five trachyte samples give similar apparent ages from 26.4 to 24.6 M.y. These results show the trachytes to be older than the tuffs, in disagreement with the geologically established sequence. The sequence of eruptions in the Siebengebirge area however (trachyte-tuff, trachyte, latite and alkaline-basalt) was confirmed wherever outcrops allow observations. This discrepancy is discussed. The apparent ages of three dated latites are in the same range (26.2 to 25.1 M.y.), in agreement with the geological sequence. The latite ages show that the time span between the eruptions of the trachytes and the latites must have been very small. Isolated basalts belonging to a fourth phase yield K/Ar ages from 25 to 19 M.y. Pliocene volcanism could not be verified in the Siebengebirge. In addition, stratigraphically well-dated glauconites from the Tertiary of the Niederrhein area were used to correlate our isotopic age date with the Cenozoic time scale.
ARK: https://n2t.net/ark:/88439/y070559
Permalink: https://geophysicsjournal.com/article/259
ARK: https://n2t.net/ark:/88439/y070559
Permalink: https://geophysicsjournal.com/article/259
Creator (Dublin Core)
Todt, W.
Lippolt, H.J.
Subject (Dublin Core)
en-US
Potassium-Argon dating
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Tertiary
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Miocene Oligocene
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Sanidine
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volcanic rocks
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paleomagnetism Siebengebirge
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Germany
en-US
Data
Publisher (Dublin Core)
en-US
Journal of Geophysics
Date (Dublin Core)
1980-03-27
Type (Dublin Core)
info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
en-US
Peer-reviewed Article
Format (Dublin Core)
application/pdf
Identifier (Dublin Core)
https://journal.geophysicsjournal.com/JofG/article/view/259
Source (Dublin Core)
en-US
Journal of Geophysics; Vol 48 No 1 (1980): Journal of Geophysics; 18-27
2643-2986
2643-9271
Language (Dublin Core)
eng
Relation (Dublin Core)
https://journal.geophysicsjournal.com/JofG/article/view/259/217