Eocene to Recent Volcanism Within the Rhenish Massif and the Northern Hessian Depression - Summary
The volcanism of the Rhenish Massif is associated with tectonic events related to the formation of the Rhine rift system. During the Tertiary, the beginning of volcanic activity shifts from west (Hocheifel, 46 Ma) to east (Northern Hessian Depression, 20 Ma). The Quaternary volcanism is restricted to two fields west of the Rhine. Except for the Siebengebirge, SiO2-undersaturated basaltoids predominate throughout the Tertiary. Their uniform major and trace element chemistry as well as their Sr (87Sr/86Sr = 0.7037 ± 0.0003) and Nd (143Nd/144Nd = 0.512858 ± 0.000055) isotope similarities are indicative of homogeneous mantle sources enriched in LIL elements prior to partial melting. Magma generation is believed to be a result of asthenosphere updoming for which evidence exists from geophysical observations and xenolith studies. Quaternary magmas presumably are related to a region of P-wave attenuation whose maximum elevation at 50 km depth is located beneath the West Eifel. From geochemical and isotopic evidence it can be concluded that these magmas in their majority come from mantle sources whose Sr (87Sr/86Sr = 0.7042 ± 0.0003) and Nd (143Nd/144Nd = 0.512695 ± 0.000045) isotopies and LIL element geochemistry are distinctly different from the Tertiary sources.
KeywordsEurope Geochemistry Explosive Olivine Miocene
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- Ahorner, L., 1983. Historical seismicity and present-day micro-earthquake activity of the Rhenish Massif, Central Europe. This Vol.Google Scholar
- Baumann, H. and lilies, J.H., 1983. Stress field and strain release in the Rhenish Massif. This Vol.Google Scholar
- Kramers, J.D. Betton, J.P., Cliff, R.A., Seek, H.A., and Sachtleben, Th., 1981. Sr and Nd isotopic variations in volcanic rocks from the West Eifel and their significance. Fortschr. Miner. Beih. 1, 59: 246–247.Google Scholar
- Meyer, W., Albers, H.J., Berners, H.P., v. Gehlen, K., Glatthaar, D., Löhnertz, W., Pfeffer, K.-H., Schnüttgen, A., Wienecke, K., and Zakosek, R., 1983. Pre-Quaternary uplift in the central part of the Rhenish Massif. This Vol.Google Scholar
- Raikes, S., 1980. Teleseismic evidence for velocity heterogeneity beneath the Rhenish Massif. J. Geophys., 48: 80–83.Google Scholar
- Seek, H.A. and Wedepohl, K.H., 1983. Mantle xenoliths from the Tertiary and Quaternary volcanics of the Rhenish Massif and the Tertiary basalts of the Northern Hessian Depression. This Vol.Google Scholar
- Semmel, A., 1983. Plateau uplift during Pleistocene time-Preface. This Vol.Google Scholar
- Spera, F.J., 1980. Aspects of magma transport. In: Hargraves, R.B. (ed.) Physics of magmatic processes. Princeton Univ. Press.Google Scholar
- Staudigel, H. and Zindler, A., 1978. Nd and Sr isotope composition of the potassic volcanics from the East Eifel, Germany: Implications for mantle source regions. Geol. Soc. Am. Annu. Meet., Toronto, pp. 497.Google Scholar
- Wedepohl, K.H., 1982. K-Ar Altersbe-stimmungen an basaltischen Vulkaniten der nördlichen Hessischen Senke und ihr Beitrag zur Diskussion der Magmengenese. Neues Jahrb. Miner. Abh., 144: 172–196.Google Scholar