Record details

    Geochemistry of the stratified volcanosedimentary complex in the central part of the České středohoří Mts., North Bohemia
Statement of responsibility
    Jaromír Ulrych, Vladimír Cajz, Kadosa Balogh, Vojtěch Erban
Other titles
    Geochemie stratifikovaného vulkanosedimentárního komplexu v centrální části Českého středohoří v severních Čechách
    Balogh, Kadosa
    Cajz, Vladimír, 1959-
    Erban, Vojtěch
    Ulrych, Jaromír, 1943-
Source title - serial
    Vol. 27
    p. 27-49
    1 obr., 5 diagr.
    Bibliografie na s. 48-49
    České resumé
    Zkr. název ser.: Krystalinikum
Classfication no.
Conspectus category
Subject group
    chemismus hornin
    izotopy radioaktivní
    vulkanity Českého středohoří
Geographical name
    České středohoří
Abstract (in english)
   On the basis of a new volcanological model and geochemical investigation in the České středohoří Mts., the following volcanostratigraphic formations ere recognized: (i) the Lower Fm. - lavas and volcaniclastics of basanitic character (36-26 Ma; Mg = 57-76; 87Sr/86Sr = 0.703128 - 0.703526 and 143Nd/144Nd = 0.512738 - 0.512849) corresponding to primitive upper mantle products; (ii) the Upper Fm. - lavas and volcaniclastics of trachybasaltic type (31-25 Ma; Mg = 41-58, 87Sr/86Sr = 0.704428 - 0.704649 and 143Nd/144Nd = 0.512679 - 0.512742) representing differentiated and partly crustal-contaminated evolved products; (iii) the Uppermost Fm. - flow(s) of basanite (24 Ma), similar in geochemical characteristics to those of the Lower Fm. Volcaniclastic products of the Lower Fm. (Mg = 51-69) and the Upper Fm. (Mg = 45-51) also substantially differ in bulk composition. the volcaniclastics underwent alteration to a different degree, hich has significantly changed their geochemical signatures.
   Enrichment and depletion in elements, normalized to the massive rocks of the same formation, are highly variable. However, contents of Ti, Al, Si, Fe and (Mn) are relatively stable and these elements represent typical immobile components,hereas Ca, Na, K and Mg contents are loer; contents of H2O and Co2 are significantly higher. trace elements such as Nb, Ta, Zr, Hf, REE and Y seem to behave as immobile, hereas Sr, Cu, Ni, Co, Cr, (Th, U) as mobile. The alteration products are mostly represented by minerals of the smectite and zeolite groups
    Česká geologická služba
Contributor code
    ČGS (UNM)
Source format
Entered date
    25. 3. 2008
Import date
    8. 8. 2012