Seismological and Geophysical Signatures of the Deep Crustal Magma Systems of the Cenozoic Volcanic Fields Beneath the Eifel, Germany
Abstract The Quaternary volcanic fields of the Eifel (Rhineland‐Palatinate, Germany) had their last eruptions less than 13,000 years ago. Recently, deep low‐frequency (DLF) earthquakes were detected beneath one of the volcanic fields showing evidence of ongoing magmatic activity in the lower crust a...
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| Format: | Article |
| Language: | English |
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Wiley
2020-09-01
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| Series: | Geochemistry, Geophysics, Geosystems |
| Subjects: | |
| Online Access: | https://doi.org/10.1029/2020GC009062 |
| _version_ | 1827771517267607552 |
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| author | Torsten Dahm Manfred Stiller James Mechie Sebastian Heimann Martin Hensch Heiko Woith Bernd Schmidt Gerald Gabriel Michael Weber |
| author_facet | Torsten Dahm Manfred Stiller James Mechie Sebastian Heimann Martin Hensch Heiko Woith Bernd Schmidt Gerald Gabriel Michael Weber |
| author_sort | Torsten Dahm |
| collection | DOAJ |
| description | Abstract The Quaternary volcanic fields of the Eifel (Rhineland‐Palatinate, Germany) had their last eruptions less than 13,000 years ago. Recently, deep low‐frequency (DLF) earthquakes were detected beneath one of the volcanic fields showing evidence of ongoing magmatic activity in the lower crust and upper mantle. In this work, seismic wide‐ and steep‐angle experiments from 1978/1979 and 1987/1988 are compiled, partially reprocessed and interpreted, together with other data to better determine the location, size, shape, and state of magmatic reservoirs in the Eifel region near the crust‐mantle boundary. We discuss seismic evidence for a low‐velocity gradient layer from 30–36 km depth, which has developed over a large region under all Quaternary volcanic fields of the Rhenish Massif and can be explained by the presence of partial melts. We show that the DLF earthquakes connect the postulated upper mantle reservoir with the upper crust at a depth of about 8 km, directly below one of the youngest phonolitic volcanic centers in the Eifel, where CO2 originating from the mantle is massively outgassing. A bright spot in the West Eifel between 6 and 10 km depth represents a Tertiary magma reservoir and is seen as a model for a differentiated reservoir beneath the young phonolitic center today. We find that the distribution of volcanic fields is controlled by the Variscan lithospheric structures and terrane boundaries as a whole, which is reflected by an offset of the Moho depth, a wedge‐shaped transparent zone in the lower crust and the system of thrusts over about 120 km length. |
| first_indexed | 2024-03-11T12:55:23Z |
| format | Article |
| id | doaj.art-3c91357279504ad09874867dc12d6d36 |
| institution | Directory Open Access Journal |
| issn | 1525-2027 |
| language | English |
| last_indexed | 2024-03-11T12:55:23Z |
| publishDate | 2020-09-01 |
| publisher | Wiley |
| record_format | Article |
| series | Geochemistry, Geophysics, Geosystems |
| spelling | doaj.art-3c91357279504ad09874867dc12d6d362023-11-03T17:01:07ZengWileyGeochemistry, Geophysics, Geosystems1525-20272020-09-01219n/an/a10.1029/2020GC009062Seismological and Geophysical Signatures of the Deep Crustal Magma Systems of the Cenozoic Volcanic Fields Beneath the Eifel, GermanyTorsten Dahm0Manfred Stiller1James Mechie2Sebastian Heimann3Martin Hensch4Heiko Woith5Bernd Schmidt6Gerald Gabriel7Michael Weber8GFZ German Research Centre for Geosciences Potsdam GermanyGFZ German Research Centre for Geosciences Potsdam GermanyGFZ German Research Centre for Geosciences Potsdam GermanyGFZ German Research Centre for Geosciences Potsdam GermanyGeological Survey of Baden‐Württemberg, State Seismological Service Freiburg GermanyGFZ German Research Centre for Geosciences Potsdam GermanyGeological Survey of Rhineland‐Palatinate, State Seismological Service Mainz GermanyLeibniz Institute for Applied Geophysics Hannover GermanyGFZ German Research Centre for Geosciences Potsdam GermanyAbstract The Quaternary volcanic fields of the Eifel (Rhineland‐Palatinate, Germany) had their last eruptions less than 13,000 years ago. Recently, deep low‐frequency (DLF) earthquakes were detected beneath one of the volcanic fields showing evidence of ongoing magmatic activity in the lower crust and upper mantle. In this work, seismic wide‐ and steep‐angle experiments from 1978/1979 and 1987/1988 are compiled, partially reprocessed and interpreted, together with other data to better determine the location, size, shape, and state of magmatic reservoirs in the Eifel region near the crust‐mantle boundary. We discuss seismic evidence for a low‐velocity gradient layer from 30–36 km depth, which has developed over a large region under all Quaternary volcanic fields of the Rhenish Massif and can be explained by the presence of partial melts. We show that the DLF earthquakes connect the postulated upper mantle reservoir with the upper crust at a depth of about 8 km, directly below one of the youngest phonolitic volcanic centers in the Eifel, where CO2 originating from the mantle is massively outgassing. A bright spot in the West Eifel between 6 and 10 km depth represents a Tertiary magma reservoir and is seen as a model for a differentiated reservoir beneath the young phonolitic center today. We find that the distribution of volcanic fields is controlled by the Variscan lithospheric structures and terrane boundaries as a whole, which is reflected by an offset of the Moho depth, a wedge‐shaped transparent zone in the lower crust and the system of thrusts over about 120 km length.https://doi.org/10.1029/2020GC009062magma reservoirsdistributed volcanic fieldsreflection seismiccrustal magma chamberdeep low‐frequency earthquakeslow velocity zone |
| spellingShingle | Torsten Dahm Manfred Stiller James Mechie Sebastian Heimann Martin Hensch Heiko Woith Bernd Schmidt Gerald Gabriel Michael Weber Seismological and Geophysical Signatures of the Deep Crustal Magma Systems of the Cenozoic Volcanic Fields Beneath the Eifel, Germany Geochemistry, Geophysics, Geosystems magma reservoirs distributed volcanic fields reflection seismic crustal magma chamber deep low‐frequency earthquakes low velocity zone |
| title | Seismological and Geophysical Signatures of the Deep Crustal Magma Systems of the Cenozoic Volcanic Fields Beneath the Eifel, Germany |
| title_full | Seismological and Geophysical Signatures of the Deep Crustal Magma Systems of the Cenozoic Volcanic Fields Beneath the Eifel, Germany |
| title_fullStr | Seismological and Geophysical Signatures of the Deep Crustal Magma Systems of the Cenozoic Volcanic Fields Beneath the Eifel, Germany |
| title_full_unstemmed | Seismological and Geophysical Signatures of the Deep Crustal Magma Systems of the Cenozoic Volcanic Fields Beneath the Eifel, Germany |
| title_short | Seismological and Geophysical Signatures of the Deep Crustal Magma Systems of the Cenozoic Volcanic Fields Beneath the Eifel, Germany |
| title_sort | seismological and geophysical signatures of the deep crustal magma systems of the cenozoic volcanic fields beneath the eifel germany |
| topic | magma reservoirs distributed volcanic fields reflection seismic crustal magma chamber deep low‐frequency earthquakes low velocity zone |
| url | https://doi.org/10.1029/2020GC009062 |
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