Szabó János szerk.: Fragmenta Mineralogica Et Palaentologica 21. 2003. (Budapest, 2003)

"Plattenkalk", and red crinoidal-brachiopodal limestones (with BÖSE's fauna, Middle Lias). The recent geological maps (PLÖCHINGER 1973, 1989), show that the red, crinoidal limestones form separate, narrow belts on the northern side of Schafberg, apparendy without direct sedimentary contact to the Lower Liassic Hierlatz limestones. According to our observations, around the Mitterscc, the very gentiy dipping, thick banks of the "Plattenkalk" are cut by two or three, great, parallel, vertical neptunian dykes, exceeding 10 m in width. The strike of the dykes is roughly parallel with the northern wall of the Schafberg (WNW to ESE). The previous palaeontological descriptions have suggested that the Lower Jurassic faunas of Schafberg are very similar to those of the Bakony Mts (Hungary). This similarity was aimed to study by in situ coUecting work, carried out by the authors during joint field-trips in June 2000, June 2001 and July 2002. We visited some outcrops at Schwarzensee (near Aschergraben, Grafenalm and Meislalm); the peak region of Schafberg; the cliffs and "kars" around Mönichsee and Mittersee (at the northern feet of Schafberg, between Spinnerin and Törlspitz); and the northern slope of Eibenberg (above the lake Mondsee) (see Figure 1). The collected fossils and samples were divided amongst the participants to study: microfacies and microfauna — O. EBLI, bivalves — I. SZENTE; gastropods —J. SZABÓ; Sinemurian (Hierlatz Limestone s.s.) brachiopods — A. DU LAI; Pliensbachian brachiopods — A. VÖRÖS. In the foUowing, we give short description and evaluation of the microfacies types and present lists of the identified fossils, with some taxonomical remarks. Figure 1 — Localities of the new collections. — Numbers indicate groups of collecting points close to each other Explanation to Plate I 1 Microfacies la — Crinoidal-biomicrite to sparite (wacke- to packstone). The often abraded crinoidal remains are mosdy surrounded by svntaxial rim-cements. — Sample SBB 2, x6. 2—3 Microfacies 2 — Filament-crinoid-biomicrite (wacke- to packstone). Besides the characteristic "filaments" (debris of thin-shelled bivalves, possibly Posidonia alpind), there occurs in Plate I: 2 a bryozoan fragment, that is impregnated on its top with a thick phosphatic crust, whereas sample MS 1 (Plate I: 3) is rich in small phosphatic and Fc/Mn-nodules. — 2: Sample SBM 7, x8; 3: Sample MS 1, XlO. 4—5 Microfacies 3 — Ostracod-echinoderm-biomicrite (wacke- to packstone). Besides the characteristic thick-shelled ostracods (e. g. 4. top) and miliolid foraminifera, sometimes also stromatactis-like features can be recognized (5). — 4: Sample SBM 2, Xl7; 5: Sample SBB 150-1, x8. 6—7 Microfacies 4 — Echinoderm-spicula-biomicrite with forams and ostracodes. Besides spicula (6), there often occur up to several cm large sponges (7), with the osculum filled by peloidal sediment and circular cements. — 6-7: Sample MA 1; 6 = x8, 7 = X 23. 8 Microfacies 2 and 5. — The lower part of the picture exhibits filamentous sediment, containing juvenile ammonites and a burrow (B) in contact to MF-5. This irregular contact is modified by pressure solution as indicated by leached crinoidal fragments (straight above "B") and a small residual layer, not visible at this magnification. — Sample MS 2, XlO.