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analogues for Miocene to Pleistocene alkali basaltic phreatomagmatic fields in the Pannonian Basin: "soft-substrate" to "combined" aquifer controlled phreatomagmatism in intraplate volcanic fields. Cent. Eur. J. Geosci. 2, 339-361. Németh K., Risso C., Nullo F. & Kereszturi G. 2011: The role of collapsing and rafting of scoria cones on eruption style changes and final cone morphology: Los Morados scoria cone, Mendoza, Argentina. Cent. Eur. J. Geosci. DOI: 10.2478/s13533-011-0008-4 Ort M. H. & Carrasco-Núñez G. 2009: Lateral vent migration during phreatomagmatic and

Bohemia) and subsequent erosional rates estimation. J. Geosci. 52, 3-4, 169-180. Risso C., Németh K., Combina A. M., Nullo F. & Drosina M. 2008: The role of phreatomagmatism in a Plio-Pleistocene high-density scoria cone field: Llancanelo Volcanic Field (Mendoza), Argentina. J. Volcanol. Geotherm. Res. 169, 61-86. Schmincke H. U. 1977: Phreatomagmatische Phasen in quartären Vulkanen der Osteifel. Geol. Jb. 39, 3-45. Shrbený O. & Vokurka K. 1985: Current state of the geochronologic and isotopic research of Bohemian Massif neovolcanites and their nodules

eastern Europe as observed by teleseismic receiver functions. Geophys. J. Int. 174, 351–376. Geissler W.H., Kämpf H., Seifert W. & Dulski P. 2007: Petrological and seismic studies of the lithosphere in the earthquake swarm region Vogtland/NW Bohemia, central Europe. J. Volcanol. Geotherm. Res. 159, 33–69. Gottsmann J. 1999: Tephra characteristics and eruption mechanism of the Komorní Hůrka Hill scoria cone, Cheb Basin, Czech Republic. Geolines 9, 35–40. Gudfinnsson G.H. & Presnall D.C. 2005: Continuous gradations among primary carbonatitic, kimberlitic

Abstract

This paper presents the results of a paleomagnetic study carried out on Plio-Pleistocene Cenozoic basalts from the NE part of the Bohemian Massif. Paleomagnetic data were supplemented by 27 newly obtained K/Ar age determinations. Lavas and volcaniclastics from 6 volcanoes were sampled. The declination and inclination values of paleomagnetic vectors vary in the ranges of 130 to 174 and -85 to -68° for reversed polarity (Pleistocene); or 345 to 350° and around 62° for normal polarity (Pliocene). Volcanological evaluation and compilation of older geophysical data from field survey served as the basis for the interpretation of these results. The Pleistocene volcanic stage consists of two volcanic phases, fairly closely spaced in time. Four volcanoes constitute the Bruntál Volcanic Field; two others are located 20 km to the E and 65 km to the NW, respectively. The volcanoes are defined as monogenetic ones, producing scoria cones and lavas. Exceptionally, the largest volcano shows a possibility of remobilization during the youngest volcanic phase, suggested by paleomagnetic properties. The oldest one (4.3-3.3 Ma), Břidličná Volcano, was simultaneously active with the Lutynia Volcano (Poland) which produced the Zálesí lava relic (normal polarity). Three other volcanoes of the volcanic field are younger and reversely polarized. The Velký Roudný Volcano was active during the Gelasian (2.6-2.1 Ma) and possibly could have been reactivated during the youngest (Calabrian, 1.8-1.1 Ma) phase which gave birth to the Venušina sopka and Uhlířský vrch volcanoes. The reliability of all available K-Ar data was evaluated using a multidisciplinary approach.

using K-Ar dating and loess stratigraphy (Furuyama et al ., 1993), the age-determination precision can be improved. Fig. 1 Index (a) and locality (b) maps. Sampling locations of Kannabe scoria cone in southwestern Japan for paleomagnetic samples (locs. 1–6) and OSL dating (loc. a). Outcrop of loc. b is shown as AT tephra under Kannabe scoria (see Fig. 2 ). We attempted paleomagnetic dating to estimate the Kannabe volcano eruption age. Furthermore, we applied OSL dating to sediments associated with the Kannabe scoria cone. 2 Geological setting Kannabe volcano in

crater outline of cone-maar mixes sketched on Google satellite images jointed to the digital elevation model overview the cross-section sketch. DEM – Digital Elevation Model; NR21 – national roadway no. 21. a) The cone-maar mixe west of Jbel Hebri; the initial cone cut in its south-western part by a late maar collapsing. b) The elongated Izgarn mixed volcano; the initial maar is covered in the north-western part by a scoria cone, which emitted a large lava flow. c) The Tahabrit volcanic complex; two cones followed the initial maar setting during the first eruptive

the Puy de Grave Noire scoria cone. In this case, the exact elements representing the constituent features of the national geosite, specifically the outcrops within the urban fabric, have not yet been explicitly inventoried. Our first source of information for locating potential geosites was pre-existing databases, historical maps and photographs, and oral discussions with local experts. We also compiled a simplified urban geomorphological map, which allowed us to have an overview of the city’s main geomorphological features and its geodiversity, and helped