Scholarlink

<p>The Cheb Volcanic Field, part of the Central European Volcanic Province (CEVP), is an active long-lived monogenetic volcanic region composed of maar-diatreme structures and scoria cones. Although hidden volcanic edifices continue to be identified along the western flanks of the Cheb Basin, the northern sector—where the earliest activity is expected—remains poorly investigated. Consequently, the early geodynamic evolution at the intersection of the Regensburg–Leipzig Zone and the Eger (Ohře) Graben is still not well constrained. To address this gap, we acquired remote‑sensing and geophysical reconnaissance data to detect previously unrecognized volcanic dikes near Bärendorf in the southern Vogtland region. Erosional incision along the local stream exposed volcanic material from NE–SW‑striking dike, enabling direct examination and confirming its composition as coherent olivine‑melanephelinite with an amygdaloidal texture. The presence of well‑preserved volcanic glass and a mineral assemblage of peridotitic forsterite, Al‑rich clinopyroxene, and nepheline allows thermobarometric modeling, indicating lower crustal magma storage at ca. 25–40&#xa0;km (corresponding to 7–12&#xa0;kbar), consistent with present crustal thickness. A <sup>40</sup>Ar/<sup>39</sup>Ar groundmass age of 30 ± 2&#xa0;Ma identifies the Bärendorf maar as one of the oldest volcanic edifices in the Cheb Basin and Elstergebirge region. These findings suggest that mantle upwelling beneath the Cheb Volcanic Field has remained stable over an exceptionally long period, beginning in the late Paleogene. This indicates that this monogenetic volcanic field is among the most long‑lived worldwide.</p> Graphical abstract <p></p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Oligocene volcanism in the western Bohemian massif: a newly identified volcanic structure reveals the early activity of the long-lived Cheb volcanic field

  • 期刊论文

  • 发表日期：

    2026年5月12日

查看全文
  • Alexander Repstock,
  • Jörg Büchner,
  • Jan Mrlina,
  • Masafumi Sudo,
  • Jacob Brauner,
  • Roman Beránek,
  • Radek Klanica,
  • Franziska Wilke,
  • Hripsime Gevorgyan,
  • Horst Kämpf

摘要

The Cheb Volcanic Field, part of the Central European Volcanic Province (CEVP), is an active long-lived monogenetic volcanic region composed of maar-diatreme structures and scoria cones. Although hidden volcanic edifices continue to be identified along the western flanks of the Cheb Basin, the northern sector—where the earliest activity is expected—remains poorly investigated. Consequently, the early geodynamic evolution at the intersection of the Regensburg–Leipzig Zone and the Eger (Ohře) Graben is still not well constrained. To address this gap, we acquired remote‑sensing and geophysical reconnaissance data to detect previously unrecognized volcanic dikes near Bärendorf in the southern Vogtland region. Erosional incision along the local stream exposed volcanic material from NE–SW‑striking dike, enabling direct examination and confirming its composition as coherent olivine‑melanephelinite with an amygdaloidal texture. The presence of well‑preserved volcanic glass and a mineral assemblage of peridotitic forsterite, Al‑rich clinopyroxene, and nepheline allows thermobarometric modeling, indicating lower crustal magma storage at ca. 25–40 km (corresponding to 7–12 kbar), consistent with present crustal thickness. A 40Ar/39Ar groundmass age of 30 ± 2 Ma identifies the Bärendorf maar as one of the oldest volcanic edifices in the Cheb Basin and Elstergebirge region. These findings suggest that mantle upwelling beneath the Cheb Volcanic Field has remained stable over an exceptionally long period, beginning in the late Paleogene. This indicates that this monogenetic volcanic field is among the most long‑lived worldwide.

Graphical abstract