| 2. |
- Bouchal, Johannes M., 1979-, et al.
(författare)
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Palynological and palaeobotanical investigations in the Miocene Yatağan basin, Turkey : High-resoluton taxonomy and biostratigraphy
- 2015
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The subject of this study is the palynology (biostratigraphic and taxonomic) and the plant remains of the lignite strip mines of Eskihisar, Salihpasalar, and Tinaz (Muğla province, western Turkey). In the Yatağan basin two Miocene to Pliocene formations are present, the Eskihisar Formation (early to middle Miocene) and the Yatağan Formation (late Miocene to early Pliocene). Both formations represent river and lake deposits consisting mainly of conglomerate, sandstone, claystone, limestone, tuffite, and intercalated lignite; the thickest, actively mined lignite seams occur in the Sekköy member of the Eskihisar Formation.Previous palynological studies of the palynoflora of the Yatağan basin mainly focussed on its biostratigraphic and palaeoclimatic significance, using conventional morphological nomenclature and light microscopy (LM).In this study the „single grain method“ is applied. Using this method, the same individual pollen grains are investigated by using both LM and scanning electron microscopy (SEM). The resulting high-resolution pictographs enable a much higher taxonomic resolution. The studied palynoflora is very rich and taxonomically diverse. Cryptogams are represented by more than ten spore morphotypes of at least three families (Osmundaceae, Pteridaceae, Polypodiaceae). Gymnosperm pollen is dominated by Cupressaceae, Gnetales (Ephedra), and Pinaceae (Cathaya, Keteleeria, Pinus). Angiosperm pollen can be assigned to 57 different genera belonging to Poaceae, Typhaceae, Altingiaceae, Amaranthaceae (Chenopodieae), Anacardiaceae, Apiaceae (three types), Asteraceae (Asteroideae, Cichoriodeae), Betulaceae (Alnus, Betula, Carpinus, Ostrya) Buxaceae, Campanulaceae, Caprifoliaceae (Lonicera), Caryophyllaceae, Dipsacaceae, Eucommiaceae, Euphorbiaceae, Fabaceae, Fagaceae (Fagus, Quercus, Trigonobalanopsis) Geraniaceae, Juglandaceae, Linnaceae (Linnum), Malvaceae, Myricaceae, Nymphaeaceae, Oleaceae (four different types), Plumbaginaceae (Armeria,), Polygonaceae (Rumex), Rosaceae, Sapindaceae (Acer), Ulmaceae (Cedrelospermum, Ulmus, Zelkova), and Zingiberales (Spirematospermum). In addition, more than two thousand plant macrofossils were collected in the course of repeated field trips, including remains of Pinaceae, Berberidiaceae (Mahonia), Betulaceae (Alnus, Carpinus), Buxaceae (Buxus), Fagaceae (Fagus, Quercus), Lauraceae, Malvaceae (Tilia), Myricaceae (Myrica), Rosaceae, Salicaceae (Populus, Salix), Sapindaceae (Acer), Smilacaceae (Smilax), Typhaceae (Typha), Ulmaceae (Zelkova). A combined analysis integrating these rich and diverse plant macro- and microfossil records will lead to a better understanding and refined reconstruction of the vegetation in the Yatağan basin during the middle to late Miocene.
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| 4. |
- Taymaz, Tuncay, et al.
(författare)
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Co-seismic Crustal Deformation of the 12 November 2017 Mw 7.4Sar-Pol-Zahab (Iran) Earthquake: integration of analysis based on DInSAR and seismological observations
- 2018
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Konferensbidrag (refereegranskat)abstract
- The November 12, 2017 Mw 7.4 earthquake that trembled near the border region between Halabjah (Iraq) andSarpol-e Zahab (Iran) is the largest ever-recorded earthquake in the Zagros Mountains since 1900. The epicenterlocation of the event suggests that the NNW trending Mountain Front Fault (MFF) has been responsible for theearthquake though it was not associated with surface faulting. Analysis of teleseismic P- and SH- body-waveformsdata indicate a well-constrained rupture propagated along the dip direction of the fault plane with an effectiverupture area of 80km long, 70km wide and focal depth of 192 km ENE dipping low-angle thrust faulting with asmall strike-slip component that produced little uplift in the region (Strike: 358o; Dip: 16o, Rake: 149o and SeismicMoment (Mo): 1.828x1020 N.m. with maximum displacement (Dmax) of 6.9m at hypocenter, and rupture velocity(Vr) of 3.2 km/s). The source rupture duration is about 45s, but the main moment release is observed in the first10s. Focal mechanism solution of the event indicates a NNW trending plane dipping 16 degrees ENE. This isin agreement with the dip direction of the MFF and the distribution of aftershocks covering an area some 50-70km wide. We explore its details in astonishment, if it is proved, that the Zagros Mountain Front fault (MFF) wasresponsible then it might have become curved at depth (?)To measure the co-seismic crustal deformation around the epicenter, we processed the ascending and descendingSentinel-1 SAR images, collected before and after the earthquake, by SNAP software and generated the interferogramsof surface deformation. The Differential InSAR (DInSAR) results show an upward and downward displacementsof 90 cm and 30 cm around the epicenter respectively. Furthermore, we investigate the differencebetween strike derived from seismological and that inferred from DInSAR satellite observations, and its possiblecauses.We do not have “best” or “right” rupture model yet, but just models satisfying for specific data sets. The aftermathof earthquakes like the 2017 Halabjah (Irak)-Sarpol-e Zahab (˙Iran) provides excellent opportunity to evaluate ourunderstanding of earthquakes and their hazards in the earthquake prone regions.
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