The shale-dominated hemipelagic succession exposed in the southwestern part of the Prague Synform preserves the most complete Ludfordian graptolite record so far encountered from peri-Gondwanan Europe. Four graptolite biozones -the Neocucullograptus inexpectatus, Nc. kozlowskii, Pseudomonoclimacis latilobus-Slovinograptus balticus and Pristiograptus fragmentalis biozones -are recognized in the middle and late Ludfordian, between the Bohemograptus tenuis Biozone and the base of the Pridoli Series. Conodont occurrences are restricted to scattered limestone beds, but enable tentative integration of the graptolite and conodont biozonal schemes. Particular attention was paid to faunal and sedimentary changes and the carbon isotope record across the middle Ludfordian Kozlowskii extinction Event. The Kozlowskii Event caused the almost simultaneous extinction of graptolites with ventrally curved rhabdosomes. The genera Bohemograptus, Polonograptus and Neocucullograptus, along with Pseudomonoclimacis dalejensis, disappeared from the fossil record. The offshore conodont fauna recorded in the section was not strongly affected and similarly the pelagic orthocerids and nektonic Ceratiocaris passed unaffected through the extinction interval. The abundant and widespread pelagic myodocopid ostracod Entomis, however, became extinct. The late Ludfordian graptolite recovery gave origin to a novel fauna of Pridoli type from taxa that emerged or just reappeared above the Kozlowskii crisis. In Všeradice and elsewhere in the Prague Synform, the recovery, manifested by the appearance of Pseudomonoclimacis latilobus and Slovinograptus balticus, closely postdates the end of the isotope excursion but pre-dates the first appearance of the conodont index 'Ozarkodina' snajdri. Here the graptolite recovery was delayed relative to the recovery of the benthic fauna. A canalized intraformational limestone conglomerate corresponds with a gap in the sedimentary record above the Kozlowskii extinction and just below the graptolite recovery. The benthic faunas from the conglomerate matrix and pebbles permit correlation with the shallower part of the basin indicating a distinct fall in sea-level. The present data demonstrate the coincidence of the graptolite crisis with benthic faunal change and eustatic fall in sea-level manifested by facies change and the carbon isotope excursion. Polonograptus chlupaci sp. nov., from the Nc. kozlowskii Biozone, is described and several other graptolite taxa are redescribed.

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Magnetic images have been produced at the distance of 0.1 mm from the polished basaltic thin sections of rocks from Prague Synform in Barrandian area. Three different magnetic textures were seen and when combined with optical imaging could be related to petrological features. The first magnetic texture revealed that most of the magnetic signature is localized within the amygdales formed later after the basalts became part of the sedimentary sequence. The second texture showed that the basaltic body contains large grain size distribution of magnetic carriers possibly with variable viscous magnetizations. The third texture suggested a presence of magnetic anisotropy of igneous origin. Such textural magnetic information along with the paleomagnetic characteristics of the basaltic rocks of Silurian age constrained the overall geological interpretation.

It has been in creas ingly real ised that geo log i cal stor age of CO 2 is a pro spec tive op tion for re duc tion of CO 2 emis sions. The CO 2 geo log i cal stor age po ten tial of sed i men tary bas ins with the ter ri tory of Slovakia, the Czech Re pub lic, Po land and the Bal tic States is here as sessed, and dif fer ent stor age op tions have been con sid ered. The most pro spec tive tech nol ogy is hydro dy namic trap ping in the deep sa line aqui fers. The uti li sa tion of hy dro car bon (HC) fields is con sid ered as a ma ture tech nology; how ever, stor age ca pac i ties are lim ited in the re gion and are mainly re lated to en hanced oil (gas) re cov ery. Pro spec tive res er voirs and traps have been iden ti fied in the Dan ube, Vi enna and East Slovakian Neo gene bas ins, the Neo gene Carpathian Foredeep, the Bo he mian and Fore-Sudetic Up per Pa leo zoic bas ins, the Me so zoic Mid-Pol ish Ba sin and the pericratonic Pa leo zoic Bal tic Ba sin. The to tal stor age ca pac ity of the sed i men tary bas ins is es ti mated to be as much as 10,170 Mt of CO 2 in deep sa line aqui fer struc tures, and 938 Mt CO 2 in the de pleted HC fields. The uti li sa tion of coal seams for CO 2 stor age is re lated to the Up per Silesian Ba sin where CO 2 stor age could be com bined with en hanced re cov ery of coal-bed meth ane.

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