Search the Community
Showing results for tags 'palaeozoic of graz'.
Found 3 results
FranzBernhard posted a topic in Fossil Hunting TripsChonetid impressions in slate (“Chonetenschiefer”) from the Plabutsch-formation, Palaeozoic of Graz, Styria, Austria (Devonian – Eifelian) The classic occurrence at Gaisbergsattel, west of Graz The Eifelian Plabutsch-formation – mostly fossiliferous limestones – of the Palaeozoic of Graz, Styria, Austria, contains locally beds of slates of various colors. Some of these beds contain abundant limonitic imprints of brachiopods and bivalves (“Chonetenschiefer”). The locality first mentioned in the literature (1871) is that at Gaisbergsattel west of Graz: Austrian map with "classic" occurrence of “Chonetenschiefer” at Gaisbergsattel (red x). Part of geological map of Kuntschnig (1937) with “Chonetenschiefer” between the two red x east of Gaisbergsattel. Here, the slate layer is up to 2 m thick, grey like mice and splits easily in flat pieces (Hanselmayer, 1957). The fauna was first listed in Heritsch (1935): Chonetes subquadrata Chonetes sarcinulata Chonetes oblonga Chonetes nova species (most abundant!) Spirifer aculeatus Pterinea fasciculata Pterinea cf. bifida Pterinea cf. costata More than 10 years ago, my first attempt looking for these rocks was not successful. A few days ago (03/29/2019), however, I stumbled over this rock by pure serendipity. A small piece of it was lying on a rather busy hiking trail (“Mariazeller Weg 06”) east of Gaisbergsattel. Relief map with my first find of “Chonetenschiefer” at the hiking trail (red x) and supposed outcrop area of this rock after the geologic map of Kuntschnig (1937). Hiking trail “Mariazeller Weg 06”, where I found my first specimen. Pic from 04/01/2019. I was able to split the rock with my fingernail – and there they were, the limonitic brachiopod imprints! A faint radial ripping is visible. No other specimen was found on the trail. Now I looked closely at the geologic map, the text of Hanselmayer (1957), and the relief map and decided to explore the area around the red line (see above), where the outcrop of this rock is supposed to be. It’s a forested area with dense undergrowth, among the undergrowth many spiky blackberry bushes… No outcrop was found, but fallen trees have exposed some rock fragments: Abundant limestones, light brownish slates and, yes, some grey slate, mostly small pieces. I split only the largest of them – and again some brachiopod imprints were found...
FranzBernhard posted a topic in Fossil Hunting TripsVery small outcrops northwest of Graz are perhaps the richest site of Silurian fossils in Styria. There may be other sites with somewhat older macrofossils in Styria, but not as rich. The outcrops are part of the Palaeozoic of Graz, a thrust sheet within the Eastern Alps, composed or Silurian to Pennsylvanian sediments. It consists of three separate nappes, the outcrop and fossils presented here belong to the Eggenfeld-member of the Kötschberg-formation within the Rannach nappe. Geological map of Styria with the Palaeozoic of Graz situated north of Graz. The red X is the location of the fossil site. Geological and structural map of the Palaeozoic of Graz. Note that the colors of the Rannach facies and Hochlantsch facies have been accidentally interchanged, the red X is the location of the fossil site. From Gasser et al. (2009). Stratigraphy and facies distribution of the Palaeozoic of Graz. Kötschberg-formation is Nr. 10 (red X), thicknesses of formations are not to scale. From Gasser et al. (2009). The age of the Eggenfeld-member is, based on conodont data, upper Silurian (Ludlow, Pridoli) to lowermost Devonian (Lochkovian). What´s special about this site is the abundance of orthocerids in some only a few dm thick layers of grey to brown dolomite and dolomitic limestone that are intercalated with tuffitic rocks. And also somewhat special is the number of papers dealing with these very small and poor outcrops. The occurrence of orthocerids is known since the 1950ies, a good up-to-date (2010) summary is this paper, it mentions 16(!) nautiloid taxa, most of them orthocerids. Its in English and includes pics of fossils and a stratigraphic section: GPZ_Eggenfeld_Histon_2010.pdf These are the seven nautiloid genera figured in this paper, no species assignment was made.
Some Fossils from the Plabutsch-Formation of the Palaeozoic of Graz, Styria, Austria (Devonian – Eifelian)
FranzBernhard posted a topic in Member CollectionsSupplementing the post in “Fossil Hunting Trips” about the Devonian Plabutsch-formation in Styria, Austria (with some background info): http://www.thefossilforum.com/index.php?/topic/90431-some-fossil-hunting-in-the-plabutsch-formation-of-the-palaeozoic-of-graz-styria-austria-devonian-–-eifelian/ I would like to post some more fossil specimens in this thread. More specimens will follow from time to time (hopefully). The first two specimens contain abundant branches of the tabulate coral Striatopora? suessi. Field pics of these specimens are already posted in the hunting trip, but here you can see also their side views, showing the alingment of the individual coral branches. (I don´t know why pics don´t look good here, but if you are zooming in, they are ok).