Paleomagnetic Results from Western Anatolia: Evidence of Microblock Rotations after Emplacement of the Lower Miocene Yuntdağ Volcanic Rocks

The eastern Aegean region has undergone north dipping subduction in the Oligocene, continental collision and then Miocene-Pliocene extension, which is associated with widespread Miocene volcanism. The aim of this study is to assess the possibility of block rotations due to stress variations in the Dikili (İzmir) province, Western Anatolia, based on paleomagnetic data obtained from 35 independent sites in addition to results from 19 sites in earlier studies. The lower Miocene Yuntdağ volcanic rocks were emplaced in three different structural blocks, the Dikili, Zeytindağ and Bergama blocks. Clockwise rotation is found in the Dikili and Zeytindağ blocks that varies from R (± DR) = 12.5° (± 7.4°) in the west to R (± DR) = 35.6°± (13.2°) in the east, respectively. In contrast, a counterclockwise rotation of R (± DR) =-38.1° (± 6.4°) resulted in the Bergama block, in the north of the Dikili and Zeytindağ blocks. A scissor-like basin evolution is suggested during the opening of the Bakırçay graben which led to counterclockwise rotation of the Bergama block and clockwise rotation of the Dikili and Zeytindağ blocks after lower Miocene to present. The rotation pattern derived from results of this study demonstrates that localized small scale deformation due to basin evolution besides regional affects must be considered as part of the deformation matrix in this area.

Indications of Deep Marine Fans in the Early Miocene Foredeep of Lower Austria: A Potential New Play

The petroleum province in Lower Austria resulted from the Alpine collision and the subsequent formation of the Vienna Basin. OMV is active in this area since its foundation in 1956. Several plays have been successfully tested and produced in this complex geological region. The main exploration focus is currently on the deep plays. However, this paper proposes a so far unrecognized and therefore undrilled play in a shallower level to broaden OMV's portfolio in Austria. Seismic re-interpretations of reprocessed 3D seismic data and structural reconstructions were used to review some of the existing plays and get novel ideas from improved understanding of processes. In the frontal accretion zone of the Alpine wedge, the Waschberg-Ždánice zone discoveries are limited to the frontal thrust unit and associated structures. The more internal parts of the thrust belt have only sparsely been drilled and are perceived not to have high-quality reservoir rocks. The detailed structural interpretations indicated that the foredeep axis during the Early Miocene was positioned in the thrust sheet located directly in front of the advancing Alpine wedge (comprising the eroding Rhenodanubian Flysch in its frontal part). Seismic amplitude anomalies can be interpreted to represent Lower Miocene basin floor and slope fans. Nearby wells did not penetrate these fans but drilled instead shale-dominated lithologies. Thus, the presence of potential sand-rich fans in front of the advancing alpine wedge is considered a potential new play in Lower Austria. Analogues are found in Upper Austria some 250 km to the West, where several large gas fields in Lower Miocene deposits located in front of the advancing Alpine wedge have been discovered by another operator. In that area the fans are only partly involved in the fold-thrust belt. In Lower Austria, these fans are located within the rear thrust sheet(s), providing a structural component to a mixed structural-stratigraphic trap. Two potential charge mechanism can be considered: a) biogenic gas charge from the organic matter of surrounding shales (like the Upper Austria analogues) or b) oil charge via the thrust fault planes from the Jurassic Mikulov Formation (the proven main source rock in the broader area). Our results add to the understanding of the Miocene structural-stratigraphic evolution of the Alpine collision zone. The definition of a potential new play may add significant value to OMV's upstream efforts in a very mature hydrocarbon province.

Decapod crustaceans from the lower Miocene Qom Formation of the Isfahan area, Central Iran

From the lower Miocene (Burdigalian) of the Qom Formation, exposed in three sections (Kuh-e-Donbeh, Bagher-Abad, and Vartun) in Central Iran, a deca-pod crustacean assemblage is described. The specimens exhibit two modes of preservation: carapaces (either isolated or with attached appendages) and isolated cheliped elements. All studied specimens are fractured and/or eroded. Based on this moderately preserved material, three brachyuran crab taxa are identified, including Mursia cf. lienharti (Bachmayer, 1962), Palaeocarpilius rugifer Stoliczka, 1871, and Necronectes sp. The occurrence of P. rugifer represents the youngest confirmed occurrence of the species, whereas other two taxa represent the first confirmed Iranian occurrences of respec-tive genera. This report enriches our knowledge on Miocene decapod assemblages of Iran, and thus helping to better understand the decapod migratory patterns along the Tethyan Sea-way.

A new deepwater lobster, Metanephrops serendipitus sp. nov. (Crustacea, Decapoda, Nephropidae), from lower Miocene of Meljski hrib (Maribor, Slovenia)

A new species of nephropid lobster, Metanephrops serendipitus sp. nov., is described from the lower Miocene (Ottnangian/Karpatian) in beds of Central Paratethys. Metanephrops serendipitus sp. nov. represents the first fossil representative of the genus from the northern hemisphere and thus extends its known palaeobiogeographical distribution. Additionally, the palaeoecology of the new species is discussed. Similar to extant species of Metanephrops, the fossil nephropid inhabited a fine-grained deep-sea environment, associated with frequent brittle stars.

A new species of fossil Calosoma (Coleoptera: Carabidae) from the Geumgwangdong Formation (Early Miocene), South Korea

In this paper, a new fossil species of Calosoma (Coleoptera: Carabidae) from the lower Miocene Geumgwangdong Formation, Pohang City, South Korea, is described. Compared with other Miocene Calosoma fossils, Calosoma kimi sp. nov. exhibits different characteristics in particular interval connection and scale patterns on the elytra. It is the first fossil Calosoma recorded from the Korean Peninsula. However, the taxonomic position of C. kimi sp. nov. within Calosoma is not clear at present though it is probably related to the complex of the subgenera Australodrepa, Calodrepa, and Calosoma.