This study presents the results of the conodont biostratigraphy and microfacies analysis carried out on the pelagic limestones of the Upper Triassic Dov?ko Section in Slovenia,which represents the eastern part of the ...This study presents the results of the conodont biostratigraphy and microfacies analysis carried out on the pelagic limestones of the Upper Triassic Dov?ko Section in Slovenia,which represents the eastern part of the Slovenian Basin.The age of the section ranges from the Lacian 1 to the Alaunian 1.The Lacian part of the succession is predominantly characterized by the representatives of the genus Ancyrogondolella.Transitional morphologies towards Alaunian faunas first appear in the Lacian 3 and become common during the Lacian-Alaunian transition.This evolutionary development coincides with a shift in microfacies from a dominantly radiolarian-bearing mudstone-wackestone-packstone to a filament-dominated wackestone-packstone,and the formation of small neptunian dykes,which may reflect environmental perturbations and/or a change in basin geometry.The proliferation of the genera Epigondolella and Mockina is observed in the Alaunian part of the section,though the genus Ancyrogondolella is still present in this interval.Systematic description of the conodont taxa is provided,and seven new species and two new subspecies are established.The new advances will be of great value in further biostratigraphic studies,especially in areas without ammonoid faunas,and in the reconstruction of the paleogeography of the Slovenian Basin.展开更多
This paper studies the microfacies, fossil contents, and the depositional environment of Wadi As Sir Limestone Formation exposed in the Al-tayyar area Zarqa Governorate, Northeastern Jordan. A total number of 35 sampl...This paper studies the microfacies, fossil contents, and the depositional environment of Wadi As Sir Limestone Formation exposed in the Al-tayyar area Zarqa Governorate, Northeastern Jordan. A total number of 35 samples were collected from a 30 m thick quarry section and used to prepare 35 thin sections. Some samples were washed over a 63 μm sieve, oven-dried at 50°C, sieved, and picked for benthic foraminifera analysis. Microscope analysis used to describe the microfacies and fossil contents. Four microfacies types and four lithological units are distinguished and described from the bottom to the top;the chalky unit (Unit-1) composed of bioclastic wackestone and biomicrite microfacies, and the dolomitic unit (Unit-2) immediately is existed above unit 1 composed dominantly of bioclastic mudstone and biomicrite microfacies. Marly limestone (Unit-3) is the following upwardly unit composed of bioclastic packestone and biosparite Microfacies, and the uppermost unit is limestone (Unit-4) consisted of bioclastic grainstone and biosparite microfacies. The fossil contents that were recognized in the studied thin sections and samples;bivalves, gastropods, pelecypods, cephalopods echinoderms, radiolarian, stromatoporoids, bone fragments, Saccaminopsis sp., Cibicidoides sp., Cibicides sp., Cyclammina sp., calcareous algae (Koninckopora and gymnocodiaceans), worm tubes, serpulids, and plentiful ostracods. The current study indicates that the Wadi As Sir Limestone Formation has deposited in a restricted circulation shallow shelf with low energy conditions most probably lagoonal environment.展开更多
基金partially supported by the Slovenian Research Agency(No.P1-0011)partially by the NKFIH PD-131536 Project。
文摘This study presents the results of the conodont biostratigraphy and microfacies analysis carried out on the pelagic limestones of the Upper Triassic Dov?ko Section in Slovenia,which represents the eastern part of the Slovenian Basin.The age of the section ranges from the Lacian 1 to the Alaunian 1.The Lacian part of the succession is predominantly characterized by the representatives of the genus Ancyrogondolella.Transitional morphologies towards Alaunian faunas first appear in the Lacian 3 and become common during the Lacian-Alaunian transition.This evolutionary development coincides with a shift in microfacies from a dominantly radiolarian-bearing mudstone-wackestone-packstone to a filament-dominated wackestone-packstone,and the formation of small neptunian dykes,which may reflect environmental perturbations and/or a change in basin geometry.The proliferation of the genera Epigondolella and Mockina is observed in the Alaunian part of the section,though the genus Ancyrogondolella is still present in this interval.Systematic description of the conodont taxa is provided,and seven new species and two new subspecies are established.The new advances will be of great value in further biostratigraphic studies,especially in areas without ammonoid faunas,and in the reconstruction of the paleogeography of the Slovenian Basin.
文摘This paper studies the microfacies, fossil contents, and the depositional environment of Wadi As Sir Limestone Formation exposed in the Al-tayyar area Zarqa Governorate, Northeastern Jordan. A total number of 35 samples were collected from a 30 m thick quarry section and used to prepare 35 thin sections. Some samples were washed over a 63 μm sieve, oven-dried at 50°C, sieved, and picked for benthic foraminifera analysis. Microscope analysis used to describe the microfacies and fossil contents. Four microfacies types and four lithological units are distinguished and described from the bottom to the top;the chalky unit (Unit-1) composed of bioclastic wackestone and biomicrite microfacies, and the dolomitic unit (Unit-2) immediately is existed above unit 1 composed dominantly of bioclastic mudstone and biomicrite microfacies. Marly limestone (Unit-3) is the following upwardly unit composed of bioclastic packestone and biosparite Microfacies, and the uppermost unit is limestone (Unit-4) consisted of bioclastic grainstone and biosparite microfacies. The fossil contents that were recognized in the studied thin sections and samples;bivalves, gastropods, pelecypods, cephalopods echinoderms, radiolarian, stromatoporoids, bone fragments, Saccaminopsis sp., Cibicidoides sp., Cibicides sp., Cyclammina sp., calcareous algae (Koninckopora and gymnocodiaceans), worm tubes, serpulids, and plentiful ostracods. The current study indicates that the Wadi As Sir Limestone Formation has deposited in a restricted circulation shallow shelf with low energy conditions most probably lagoonal environment.
