Depoziční prostředí a provenience spodnopaleozoických klastik ve vrtu Měnín-1, jjz. od Brna
Roč.14,(2007)
An unusual, more than 1.7 km thick successions of Paleozoic siliciclastic strata were drilled in an intermittently cored Měnín-1 borehole in 1973. The boundary between the Cambrian and Devonian siliciclastics has recently been localized at the drilling depth of 473 m, i.e. only 70 m below the base of the limestones. Several facies that identify similar depositional environments were found both in the numerous Cambrian sedimentary fills and thin Devonian siliciclastics. There were repeated changes between the terrestrial and shallow marine conditions, but the previling volumes of these siliciclastics were probably deposited in environments of braided deltas. The chemical compositions of detrital garnets and tourmalines sampled from both the Cambrian and Devonian sediments identify a similar material sources. Metasediments, mainly gneisses and schists as the main source rocks, were identified for the oldest parts of the Lower Cambrian stratal succession. Higher in these successions, a gradual decrease of granitoids in the Lower Cambrian source rocks was proved. Above the major, Lower Cambrian–Middle Devonian hiatus, the composition of translucent heavy mineral assemblage is strongly affected by redeposition from older sediments.
siliciclastics; sedimentary environments; heavy minerals; sediment provenance; Cambrian; Devonian; Southern Moravia
Bridge, J. S. (2003): Rivers and Floodplains. – Blackwell Publ., 1–491. Oxford.
Čopjaková, R. (2001): Využití chemismu detritických granátů při zjišťování provenience sedimentů kulmu Drahanské vrchoviny. – MS, PřF MU, Brno.
Fatka, O. – Vavrdová, M. (1998): Early Cambrian Acritarcha from sediments underlying the Devonian in Moravia (Měnín borehole, Czech Republic). – Věst. Ústř. Úst. geol., 1, 73, 55–60. Praha.
Harper, C. W. (1984): Improved method of facies sequence analyses. – In: Walker, R. G. (Ed.): Facies models. – Geosci. Can. Rep. Ser., 11–13.
Krumbein, W. C. – Dacey, M. F. (1969): Markov chains and embedde Markov chains in geology. – Math. Geology, 1, 79–96.
Jachowicz, M. – Přichystal, A. (1997): Nález spodnokambrických sedimentů v hlubokých vrtech na jižní Moravě. – Geol. výzk. Mor. Slez. v r. 1996, 64. Brno.
Leichmann, J. (1996): Geologie und Petrologie des Bruenner Massivs. – MS, Universitaet Salzburg.
Mikuláš, R. – Nehyba, S. (2001): Ichnofosilie v horninách předpokládaného spodnokambrického stáří ve vrtu Měnín-1 na jižní Moravě. – Geol. výzk. Mor. Slez. v r. 2000, 47–50. Brno.
Miall, A. D. (1996): The geology of fluvial deposits: sedimentary facies, basin analysis and petroleum geology. – Springer–Verlag, 1–582. Berlin, Heidelberg, New York.
Morton, A. C. – Hallsworth, C.R. (1994): Identifying provenance–specific features of detrital heavy mineral assemblages in sandstones.– Sediment. Geol. 90, 241–256.
Morton, A. C. – Hallsworth, C.R. (1999): Processes controlling the composition of heavy mineral assemblages in sandstones.– Sediment. Geol. 124, 3–29.
Postma, G.(1990): Depositional architecture and facies of river and fan deltas? A synthesis. In: Collela A., Prior D. B. (Eds.): Coarse– grained deltas. Spec. Publ. Int. Asoc. Sediment., 10, 13–27.
Purkyňová, E. – Gilíková, H. – Jachowicz, M. – Filipiak, P. (2004): Paleobotanical records from basal Devonian clastics in Měnín and Kozlovice boreholes (Moravia, Czech Republic). – Čas. Slez. Muz. Opava (A)3, 53, 193–204. Opava.
Ramos, A. – Sopeña, A. (1983): Gravel bars in low sinuosity streams (Permian and Triassic, central Spain). – IAS, Spec. Publ., 6, 306–312. Oxford.
Vallová, S. (2005): Granáty v granitoidních horninách východního okraje Českého masivu. – MS, PřF MU, diplomová práce. Brno.
Vavrdová, M. – Bek, J. (2001): Further palynomorphs of Early Cambrian age from clastic sediments underlying the Moravian Devonian (borehole Němčičky–3). – Czech Geol. Survey Bull., 2, 76, 113–115. Praha.
Vavrdová, M. – Mikuláš, R. – Nehyba, S. (2003): Lower Cambrian siliciclastic sediments in Southern Moravia (Czech Republic) and their paleogeographical constraints. – Geol. Carpathica, 2, 54, 67–79. Bratislava.
Wright, V. P. – Marriott, S. B. (2007): The dangers of taking mud for granted: Lessons from Lower Old Red Sandstone dryland river systems of South Wales. – Sediment. Geol., 195, 91–100.
Zukalová, V. – Kalvoda, J. – Galle, A. – Hladil, J. (1981): Biostratigrafie paleozoika v hlubokých vrtech jihovýchodně od Brna, 7–30.
In: Kalvoda, J. (Ed.), Biostratigrafie paleozoika na jihovýchodní Moravě, Knihovnička zemního plynu a nafty (Hodonín), 2, 255 str., 1 příloha.