TY - CHAP A1 - Schüssler, Ulrich A1 - Okrusch, M. A1 - Seidel, E. A1 - Richter, P. T1 - Geochemical characteristics of metabasites in different tectonic units of the North-East-Bavarian crystalline basement N2 - Comprehensive geochemical investigations of rnetabasites yielded constraints for a correlation of, or discrimination between the different tectonic units within the northeast Bavarian crystalline basement. The Münchberg nappe pile consists of at least five large tectonic units which exhibit differences in lithology, in part also in metamorphie grade and in metamorphie history. The metabasites in each of these nappes show their own, significant geochemical characteristics. The lowermost tectonic unit, the Bavarian lithofacies, includes the anchimetamorphie Ordovician Randschieferserie which contains alkaline basalts. In their geochemistry, they are sirnilar to the metabasites of the Fichtelgebirge crystalline complex in the autochthonous Saxo-thuringian. The next higher tectonic unit of the Münchberg nappe pile, the Prasinit-Phyllit-Serie contains metabasites which can be derived from subalkaline basalts with a clear calc-alkaline tendency. There is a striking geochemical resemblance to the metabasites of the Erbendorf Greenschist Zone (EGZ) underscorinq the similar lithology of both allochthonous units which appear to be in a similar tectonic position. The Randamphibolit-Serie higher up in the Münchberg nappe pile consists of metabasites with tholeiitic characteristics and a pronounced differentiation trend. The next higher tectonic unit, the Liegendserie of the Münchberg gneiss cornplex s. str., contains metagabbros to metagabbronorites with a high-Al basaltic composition. The amphibolites and banded hornblende gneisses of the overlying Hangendserie are of subalkaline basaltic character with calc-alkaline affinity. The Zone Erbendorf-Vohenstrauss (ZEV) is currently regarded as an allochthonous unit equivalent to the higher crystalline nappes of the Münchberg pile. However, the geochemical character of the metabasites do not encourage such a correlation. Neither the schistose and striped amphibolites nor the flaseramphibolites of the ZEV with their N-KORB and E-MORB character respectively, find convincing counterparts in the crystalline nappes of the Münchberg pile. However, an interestingly close resemblance exists between the schistose and striped amphibolites in the ZEV, on the one hand, and in the autochthonous Zone Tirschenreuth- Mähring (ZTM) and the adjacent Moldanubian sensu strictu, on the other. Owing to the absence of age criteria, our results cannot be used, so far, to reconstruct the paleogeographical position of the individual tectonic units, based on the geochemical characteristics of their respective metabasites. Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39221 ER - TY - CHAP A1 - Hammann, W. A1 - Heunisch, C. A1 - Schüssler, Ulrich T1 - Organische Mikrofossilien (Chlorophyta, Acritarcha, Sporae diversae, Scolecodonten) aus den Schichten des Streichengrundes, Unterdevon, im Raum Guttenberg-Kupferberg des Frankenwaldes. N2 - Aus einer SE von Guttenberg im Frankenwald auftretenden Abfolge von bisher zur ordovizischen Randschieferserie gezählten grauen Schiefern und Tuffiten, den "Streichengrund-Schichten", wird eine reiche Assoziation organischer Mikrofossilien mit einem unterdevonisehen (Unter-Ems) Ablagerungsalter und mit aufgearbeitetem Unterordovizium (Ober-Arenig) beschrieben. Diese umfaßt 11 Arten der Chlorophyten, 44 Arten der Acritarchen - davon neu Uncillisphaera spinifurcillata 11. sp., sowie 42 Taxa der Sporae dispersae und Scolecodonten. Die somit als tektonische Schuppe innerhalb der ordovizischen Randschieferserie liegenden Streichengrund-Schichten stellen eine im Frankenwald bisher unbekannte Fazieseinheit des Unterdevon dar, die mit ihren vulkanischen Anteilen bayerische, mit ihren klastischen Anteilen thüringische Züge besitzt. Lithologische Vergleiche mit den in streichender Verlängerung nach S hin auftretenden dunklen Schiefern der stratiformen Lagerstätte von Kupferberg legen ein Unterdevon-Alter auch für diese Einheit nahe. N2 - From aseries of grey shales and tuffites, the "Streichengrund beds" whieh erop out SE of Guttenberg in the Frankenwald, a rieh assodation of organic microfossils is described. It comprises 11 species of chlorophytes, 44 species of acritarchs, including the new species Uncinisphaera spinifurcillata n. sp., 41 taxa of the Sporae dispersae, and scolecodonts. The mieroflora of the Streichengrund beds, which were considered so far to represent apart of the Ordovician Randschiefer, indicates a Lower Devonian (early Emsian) age of deposition and also contains reworked Lower Ordovician (Upper Arenigian) components. Therefore the Streichengrund beds occur within the Randschiefer as a tectonically isolated wedge. They represent a lithologie unit unknown so far in the Lower Devonian of the Frankenwald and can be considered to be a transitional fades between the vo\canically influenced Bavarian and the siliciclastic Thuringian Lower Devonian facies of the Frankenwald. Because the dark shales containing the stratiform ore deposit of Kupferberg are situated in the prolongation of a strike of and are lithologically very comparable to the Streichengrund beds, a Lower Devonian age is inferred for these deposits, too. KW - Frankenwald KW - Unterdevon KW - Ordovizium KW - Acritarchen KW - Sporen KW - Lower Devonian KW - Ordovician KW - acritarchs KW - spores Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39152 ER -