Cherty limestones, marls and radiolarites are widespread in the Hallstatt Mélange of the Northern Calcareous Alps. The mélange was formed during the Neotethyan orogeny in a series of deep-water basins that progressively developed in front of the advancing nappe front. The low thermal overprint of these rocks favors the good preservation of radiolarians (polycystines) that have been used for dating and reconstructing the Jurassic tectonostratigraphy of the area. This paper describes rich Middle–Late Jurassic radiolarian faunas from four localities in the Hallstatt Mélange near Bad Mitterndorf in Austria. Two different successions, both spanning from the Bathonian to the Oxfordian, are dated. In the first succession, the radiolarites are intercalated between or occur as matrix in mass-flow deposits originating from the accretionary wedge. The second succession is nearly 100 m thick but is devoid of mass-flow deposits and documents a continuous radiolarite deposition in greater distance from the nappe stack. Both successions are ascribed to the Sandlingalm Basin, which evolved on a relatively distal continental margin during early stages of the orogeny.The highly diverse and well-preserved radiolarian assemblages have been used for a detailed taxonomic study. Two new families are described: Minocapsidaen. fam. andXitomitridaen. fam.; six new genera are describedDoliocapsan. gen.,Crococapsan. gen.,Parvimitrellan. gen.,Xitomitran. gen.,Campanomitran. gen., andMizukidellan. gen. In addition, one new replacement name,Takemuraella(proTriversus), is introduced, the diagnoses of 6 genera are emended, and two new species are described:Hemicryptocapsa nonagintan. sp. andMizukidella mokaensisn. sp.
1 February 2006 in International Journal of Earth Sciences
The late Middle to early Late Jurassic mélange of the eastern Zlatibor Mountain (Gostilje–Ljubiš–Visoka–Radoševo areas) in the Dinaridic Ophiolite Belt contains a mixture of (A) blocks of Triassic oceanic crust and radiolarites, and (B) open marine limestone and radiolarite blocks of the overthrusted distal Adria margin. We describe the microfacies and present biostratigraphic data from radiolarite and carbonate clasts and blocks and the radiolaritic-argillaceous matrix. The radiolarians and conodonts yield Middle to Late Triassic (Ladinian to Norian) ages for the provenance areas from which the ophiolite, radiolarite and carbonate blocks and clasts derived. The provenance areas of the components in the Gostilje–Ljubiš–Visoka–Radoševo mélange are determined as (1) the ocean floor of the Neo-Tethys, and (2) the continental slope/distal parts of the shelf. In the course of ophiolite obduction, the continental slope and the ocean floor components were transported by mass movements into newly-formed, trench-like basins in front of the westward propagating obduction of the Dinaridic ophiolite nappe stack. These basins were later incorporated in the nappe stack forming the typical features of a syntectonic mélange. The new radiolarian biostratigraphic data confirm Middle Triassic formation of the Neo-Tethys Ocean, parts of which were closed during obduction commencing in the late Early or early Middle Jurassic. The data clearly speak in favour of one Neo-Tethys Ocean to the east, from which the ophiolites of the Dinaridic Ophiolite Belt derived as far-travelled ophiolitic sheets.
For the first time in English, we present a summary of the international programme of excavation work carried out between 1990 and 2001 in and around the Iron Age salt-mining complex of the Diirrnberg region, south of Salzburg. First we describe the results of excavation in the prehistoric adits, and of work to locate and survey associated settlements. This is followed by a series of specialist reports embracing floral and faunal remains, palaeodiet and parasitology, leather and woodworking and other crafts. The evidence suggests that a complex inter-relationship existed between the Diirrnberg and other communities in the Alpine foreland. It is assumed that the Diirrnberg was under the control of an elite – perhaps a local dynasty whose wealth is reflected in the graves.