Field Trip B TRIASSIC CONODONT LOCALITIES OF THE ...

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The Ecxursion DAY 1 Feuerkogel near Bad Aussee, Middle and Upper Triassic Hallstatt Limestone (Stratotype of the Tuvalian Substage; Anisian to Lower Norian conodonts). Access of the locality from Hallstatt is along the river Traun via Bad Aussee to Mitterndorf. Leaving Hallstatt on the roadside mainly Dachstein Lst. is exposed representing a cyclic lagoonal type sediment of the so-called „Loferer type" (A. G. FISCHER 1964). Upon Bad Aussee the valley opens and forms a wide depression filled with fluviatil Quarternary deposits. From Mitterndorf the route runs through the Salza valley to Kochalm and further westward on a forrest road to Teltschenalm. Starting at an altitude of approx. 1350 m we will arrive at Feuerkogel (1625 m) after one hour walk. On the official topographic map (sheet 97, Mitterndorf) Feuerkogel is indicated as an unnamed elevation on the east side of Mount Rötheistein. The mountain Feuerkogel (fig. 9) is one of the numerous tectonic blocks developed in Hallstatt fades which in the surroundings of Mitterndorf tectonically overlay the Dachstein nappe (cf. TOLL- MANN 1960). Feuerkogel consists of some 50 m of moderately north dipping Hallstatt Lst. The complete section is exposed at the southern side beginning in the Middle Anisian with Reifling Lst. (Kockeli-Zone). They are followed by dark marls presumably of Upper Anisian age, forming a small depression. On the ascent to the peak the following members of Hallstatt Lst. will be passed: 1) Lower Ladinian „Grauvioletter Bankkalk" (grey violet bedded 1st.), poor in conodonts; 2) Ladinian „Roter Knollenflaserkalk" (red nodular flaser-lst.), poor in conodonts; 3) Upper Ladinian to lowermost Norian „Roter Bankkalk" (red bedded 1st.) with abundant conodonts but in part condensed faunas; 4) Lower Norian „Massiger Hellkalk" (massive light 1st.) rich in conodonts, forming the peak. Compared with earlier reports (KRYSTYN 1973) the age of the „Roter Knollenflaserkalk" and of „Roter Bankkalk" has been slightly changed depending on new conodont evidence. The classic ammonite localities described at Feuerkogel occur in the „Roter Bankkalk" and in part also in the overlying „Hellkalk". Their maximum age range from the Upper Ladinian to the Lower Norian; faunas from two fissures even indicate Middle and Upper Norian. During the excursion three fossil localities (quarries) will be visited (Fl, F4, F5). Two others, still existing, are due to their sedimentary structures too complicated and therefore not suited for detailed biostratigraphic studies. „The Feuerkogel is probably one of the most famous cephalopod collecting sites in the world. The rocks exposed near its peak have yielded thousands of specimens of ammonoids, nautiloids, pelecypods and other invertebrate fossils. During the last century a rather sizable industry was developed through wich an extraordinary number of cephalopods were quarried out of these rocks and sold to museums, collectors, and tourists. MOJSISOVICS in the last half of the last century described 444 cephalopod species from these strata" (MOSHER 1968, p. 903); DIENER added some 20 more. Conodont research The Feuerkogel represents one of the most important Triassic conodont localities of the world, both for stratigraphic reasons and concerning abundance of conodonts. The locality is closely related to the study of Triassic conodonts. It is the type locality of three diagnostic platform conodonts of the Triassic, namely, Gladigondolella tethydis (HUCKRIEDE 1958, p. 157), Gondolella navicula (HUCKRIE- DE 1958, p. 147), and Gondolella excelsa (MOSHER 1968, p. 158). Furthermore, a certain number of Triassic ramiform elements were first described at Feuerkogel. Following HUCKRIEDE 1958, MOSHER 1968, p. 915 carried out an excellent study of the conodont fauna. He also drew attention to the discrepancies between the ranges of several index species (quarry Fl) and concluded stratigraphic condensation. Some years later KRYSTYN 1972, 1973 presented a detailed stratigraphic synthesis of the Feuerkogel and its main fossil sites including a correlation of ammonoid and conodont biostratigraphy. KRYSTYN's results were questioned and critizised in a quite unusual way by KOZUR 1973 who — unfortunately — never was able to visit parts of the section at Feuerkogel. His samples were collected by another person and sent to him. Though KOZUR had no real stratigraphic control of his samples he tentatively assigned them to certain beds of the section. This, in fact, may explain his misinterpretations. So far, Feuerkogel has been the only place in the Tethys realm where it is possible to correlate precisely the ammonite and conodont chronologies in the Upper Karnian and Lower Norian. Beside this 81
oo to GEOL.KARTE DES FEUERKOGELS NNW SSE L. KRYSTYN , 1 971,ergänzt J_ 45° - 1 - 30° 4- 15° Hangsch utt, Böden Massiger Hellkalk CUNTERNOR) Roter Bankkai k , CO LADIN-U.NORD ..... Styriaca - + Austriaca-Lum. Roter Knollenf laserkalk (LADIN) Grauvioletter Bankkalk CLADIN) Mergel C OBERANI S ? ) Reif linger-Schichten C M.ANIS) •+- flache Lagerung „— Störung /<
Page 1: Field Trip B TRIASSIC CONODONT LOCA
Page 4 and 5: - Overthrusts and southern border o
Page 6 and 7: According to G. SCHÄFFER (1976), E
Page 8 and 9: History of geologic research in the
Page 10 and 11: Stratigraphy of the Hallstatt regio
Page 12 and 13: Lithostratigraphy A comprehensive s
Page 14 and 15: duced and therefore are supposed to
Page 16 and 17: localities (Taubenstein, Leislingwa
Page 18 and 19: similar but have different ranges (
Page 20 and 21: anee of Gladigondolella tethydis. I
Page 24 and 25: the section at Feuerkogel apparentl
Page 26 and 27: lella tethydis and Gondolella polyg
Page 28 and 29: Malayites paulckei Guembetites jand
Page 30 and 31: 1— :< :n DC 5EVAT ALAUN cH CD z L
Page 32 and 33: ^o PROFIL B BEI P IV 5 rote Schtefe
Page 34 and 35: ocks is markedly sharp. The irregul
Page 36 and 37: thology as well as by the main Chor
Page 38 and 39: — Geol. Paläont. Mitt. Innsbruck
Page 40: Plate 11 Magnification 100 x Fig. l
Page 44: Plate 13 Magnification 100 x Feuerk

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