搜索结果: 1-15 共查到“理学 Ordovician”相关记录31条 . 查询时间(0.054 秒)
A 12- to 14-million year faunal diversity cycle in the Ordovician of Western Baltica
12- to 14-million year faunal diversity cycle Ordovician of Western Baltica
2009/12/3
The faunal (all fossil groups) species diversity curve for the Ordovician of Norway shows a strong and statistically significant cycle with a period of 12 to 14 million years. The cycle is supported b...
Dendroid graptolites in the Elnes Formation (Middle Ordovician) Oslo Region,Norway
Dendroid graptolites Elnes Formation Oslo Region
2009/12/3
Well preserved relief specimens of the dendroid graptolites Dendrograptus rigidus Bulman, 1936 and Acanthograptus sp. have been discovered in a siltstone within the basal Engervik Member of the Elnes ...
Two species belonging to the Class Stelleroidea are described from Ordovician rocks of the Oslo Region, Norway. These are the asteroid, Cnemidactis osloensis n.sp, from the Elnes Formation (Llanvirn) ...
Brachiopod bio- and ecostratigraphy in the lower part of the Arnestad Formation (Upper Ordovician),Oslo Region,Norway
Brachiopod bio- and ecostratigraphy lower part Arnestad Formation
2009/12/3
The aim of the present study is to improve knowledge of the brachiopod fauna in the lower part of the Arnestad Formation (Caradoc) in the Oslo-Asker district and to document faunal changes prior to th...
Conodonts of the Kiviõli Member,Viivikonna Formation (Upper Ordovician) in the Kohtla section,Estonia
conodonts taxonomy biostratigraphy Kukruse Stage Ordovician Estonia
2009/10/22
Conodont faunas from the kukersites and kukersitic limestones of the Kiviõli Member are similar to coeval collections from other sedimentary facies and there are no taxa endemic to this unusual...
Lower Ordovician Leetse Formation in the North Estonian Klint area
Leetse Formation conodont biozonation grain-size data glauconite mineralogy
2009/10/21
Sequences of the Leetse Formation were studied in order to find out the conodont biozonation, grain-size distribution, and glauconite mineral properties and their variations along the North Estonian K...
The Early Ordovician trilobite distribution and zonation of the East Baltic
trilobites biozonation Hunneberg Billingen Lower Ordovician Baltoscandia
2009/10/21
Biozones of the East Baltic Early Ordovician trilobites were studied based on the trilobite distribution in northwestern Russia, Estonia, and Sweden. New data on trilobite distribution reveal the diac...
Ordovician timescale in Estonia:recent developments
stratigraphy timescale Ordovician graptolites chitinozoans conodonts Estonia
2009/10/21
Over 150 years of progress in the Ordovician geology and stratigraphy of Estonia has resulted in one of the most precise Ordovician timescales in the world. In this paper, an up-to-date version of the...
Dolomitization and sedimentary cyclicity of the Ordovician,Silurian,and Devonian rocks in South Estonia
dolomitization sedimentary cyclicity diagenesis dolomite XRD porosity
2009/10/21
The distribution and composition of dolomitized rocks and stoichiometry of dolomite in southern Estonia in the Ordovician, Silurian, and Devonian were studied on the background of the facies, sediment...
A new chitinozoan species from the Upper Ordovician of the East Baltic
chitinozoans Upper Ordovician Baltica Avalonia
2009/10/21
A new species Conochitina rugata, earlier treated as nomen nudum, is formally defined. The species has been identified in the upper part of the Pirgu Stage in many East Baltic sections of the Baltica ...
Recent developments in the Upper Ordovician and lower Silurian conodont biostratigraphy in Estonia
conodonts biostratigraphy Upper Ordovician Llandovery Wenlock Estonia
2009/10/21
The current state of and the latest developments in the conodont-based biostratigraphical studies of Upper Ordovician and lower Silurian strata in Estonia are discussed. An updated conodont zonation i...
Platystrophia (Orthida) and new related Ordovician and Early Silurian brachiopod genera
Rhynchonelliformea Platystrophiidae Baltica Avalonia Laurentia new taxa
2009/10/21
More than 150 Ordovician and Early Silurian brachiopod species have been assigned to the genus Platystrophia King,1850 mainly on the basis of their Spirifer-like shell exteriors. King’s concept o...
Cornulitid epibionts on brachiopod shells from the Late Ordovician(middle Ashgill) of East China
cornulitids brachiopods Ordovician South China
2009/10/21
This is the first record of Cornulites sp. as an epibiont on brachiopods from the middle Ashgill, Late Ordovician, of the South China Palaeoplate. Twenty-one cornulitid specimens were found attached t...
Hulterstad brachiopods and associated faunas in the Vormsi Stage (Upper Ordovician,Katian) of the Lelle core,Central Estonia
Hulterstad brachiopods chitinozoans scolecodonts Vormsi Stage Ordovician Estonia
2009/10/21
Integrated palaeontological and sedimentological study of the Upper Ordovician Vormsi Stage in the Lelle drill core section, Central Estonia, revealed an association of shelly fauna containing the end...
Conodont biostratigraphy in the Middle-Upper Ordovician boundary beds of Estonia
conodonts correlation biostratigraphy Ordovician Estonia
2009/10/21
Conodonts of the uppermost Uhaku, the Kukruse, and the lower Haljala stages (uppermost Darriwilian and lower Sandbian) of Estonia are discussed. The distribution of conodonts within the Pygodus serra,...