Podrobnosti záznamu

Název
    Paleogeografie terciérních sedimentů severočeské pánve
Údaj o odpovědnosti
    Antonín Elznic, Zdena Čadková, Pavel Dušek
Další názvy
    Palaeogeography of the Tertiary sediments of the North Bohemian Basin (Czech Republic)
Autor
    Čadková, Zdena
    Dušek, Pavel
    Elznic, Antonín
Jazyk
    česky
    německy
Zdrojový dokument - seriál
    Sborník geologických věd. Geologie
Svazek/č.
    Roč. 48
Strany
    s. 19-46
Rok
    1998
Poznámky
    15 obr., 2 tab.
    15 obr., 2 tab., 33 bibl.
    Anglické resumé
    il.
    Obsahuje bibliografické odkazy
    Zkr. název ser.: Sbor. geol. Věd, Geol.
Předmětová skupina
    mapa paleogeografická
    miocén
    oblast snosová
    oligocén
    pánev sedimentační
    profil vrtný
    prvky stopové
    sedimentace deltová
    sedimentace lakustrinní
    severočeská pánev
    uhelná sloj
Geografické jméno
    Bílina (Teplice)
    Chomutov
    ČR-Čechy
    Havraň (Most)
    Hrdlovka (Teplice)
    Kopisty (Most)
    Most
    Pětipsy (Chomutov)
    Ústí nad Labem
    Žatec (Louny)
Klíčové slovo
    Paleogeografie
    Pánve
    Sedimentů
    Severočeské
    Terciérních
Abstrakt (anglicky)
   Lost lasting open pit mining of brown coal in the North Bohemian Tertiary Basin yielded enormous amount of geological data of all types. That is why geologists, and especially economic geologists, could reconstruct the detailed image of this basin. On the other hand, however, stratigraphical scheme of this basin is comparatively vague and that is why all the attempts of palaeogeographic reconstructions are affected by this inperfect chronostratigraphical column. These limiting factors are caused by the fact that only continental depositional sequence is present, facial changes are extremely fast and synsedimentary erosion caused gaps in sedimentation. Direct correlation with Tertiary marine, properly biostratigraphically characterized, sequences is not possible. Index fossils are not defined in the Tertiary of the North Bohemian. That is why its stratigraphy is based only on the whole assemblages of microflora and pollen.
   Thus these sediments are traditionally subdivided only into three stratigraphical units. Palaeomagnetic research of Tertiary lacustrine sequences is only in the initial stage and isotope data are available only from neovolcanites. Presented study is based on the evaluation of mineral and chemical composition of a sedimentary complex. Regional geochemical research proved to be most successful, mainly analysis of contents of trace elements in clayey sediment. These data were completed by a reevaluation of older data on the content of heavy minerals in coarser clastic sediments. The above mentioned methods led to the subdivision of the whole complex into two subcomplexes which can be called "Lower and Upper complexes of basinal sediments". The Lower Complex can be characterized from the geochemical view as very special one having trace elements derived from neovolcanites.
   The composition of its claystones often corresponds to the composition of neovolcanites with lesser contents of immobile elements. Locally, the volcanogenic compouds are masked by the increase input of clastic material from the adjacent Krušné hory Mts. crystalline rocks, Upper Cretaceous and/or Late Palaeozoic sediments. The Upper Complex can be characterized by increased contents of potassium, rubidium, caesium and magnesium which correspond to source rocks of intermedial character. Its claystones are surprisinngly homogenous and the amount of volcanic elements drops to the level of common argillites. The boundary between these two complexes can be found in all the types of basinal sediments. In the claystones it can be identified even macroscopically, but in the aggregate coal seam only by means of silicate analyses of clastic admixtures, as coal ashes.
   The boundary between the Lower and Upper complexes reflects sudden change in the source areas of clastic material and changes in the river system of the whole Bohemian Massif. Two hundred drilling, regularly distributed through the North Bohemian Masin offered voluminous material for a geochemi

   Long lasting open pit mining of brown coal in the North Bohemian Tertiary Basin yielded enormous amount of geological data of all types. That is why geologists, and specially economic geologists could reconstruct the detailed image of this basin. On the other hand, however, stratigraphical scheme of this basin is comparatively vague and that is why all the attempts of palaeogeographical reconstructions are affected by this inperfect chronostratigraphical column. These limiting factors are caused by the fact that only continetal depositional sequence is present, facial changes are extremely fast and synsedimentary erosion caused gaps in sedimentation. Direct correlation with tertiary marine, properly biostratigraphically characterized, sequences is not possible. Index fossils are not defined in the tertiary of the North Bohemia. That is its stratigraphy is based only on the whole assemblages of microflora and pollen.
   Thus these sediments are traditionally subdivided inly into three stratigraphical units. Palaeomagnetic research of Tertiary lacustrine sequences is only in the initial stage and isotope data are available only from neovolcanites. Presented study is based on the evaluation of mineralogical and chemical composition of a sedimentary complex. regional geochemical research proved to be most succesful, mainly analysis of contents of trace elements in clayey sediment. These data were completed by reevaluation of older data on the content of heavy minerals in coarser clastic sediments. The above mentioned methods led to the subdivision of the whole complex into two subcomplexes which can be called "Lower and Upper complexes of basinal sediments". The Lower Complex can be characterized from the geochemical view as very special one having trace elemnts derived from neovolcanites.
   The composition of its claystones often corresponds to the composition of neovolcanites with lesser contents of immobile elements. Locally, the volcanogenic compounds are masked by the increased input of clastic material from the adjacent Krušné hory Mts. crystalline rocks, Upper Cretaceous and/or Late Palaeozoic sediments. The Upper Complex can be characterized by increased contents of potassium, rubidium, caesium and magnesium which correspond to source rocks of intermedial character. Its claystones are surprisingly homogenous and the amount of volcanic elements drops to the level of common argillites. The boundary between these two complexes can be found in all types of basinal sediments. In the claystones it can be identified even macroscopically, but in the aggregate coal seam only by means of silicate analyses of clastic admixtures, as coal ashes.
   The boundary between the Lower and Upper complexes reflects change in the source areas of clastic material and changes in the river system of the whole Bohemia Massif. Two hundred drillings, regularly distributed through the North Bohemian basin ofered voluminous material for a geochemical research an
Přispěvatel
    Česká geologická služba
Kód přispěvatele
    ČGS (UNM)
Zdrojový formát
    U
Datum vložení
    28. 3. 2008
    6. 3. 2009
Datum importu
    8. 8. 2012