Trace Fossils and Their Sedimentary Environment of Ordovician Majiagou Formation in the North-west of Henan Province
doi: 10.14027/j.cnki.cjxb.2015.02.001
- Received Date: 2014-02-15
- Rev Recd Date: 2014-04-25
- Publish Date: 2015-04-10
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Key words:
- trace fossils /
- ichnoassemblage /
- sedimentary environment /
- Ordovician /
- Majiagou Formation
Abstract: Trace fossils from Ordovician Majiagou Formation consist of at least 10 ichnogenera and 17 ichnospecies, namely, (1)Domichnia: Psilonichnus upsilon, Thalassinoides callianassa, Thalassinoides horizontalis, Rhizocorallium jenense.(2)Foidichnia: Chondrites type-1, Chondrites type-2, Chondrites intricatus, Palaeophycus tubularis, Palaeophycus heberti, Planolites montanus, Planolites annularius, Phycodes palmatus.(3)Pascichnia: Helminthopsis ichnosp., Helminthopsis abeli, Helminthopsis hieroglyphica, Gordia molassica, Scolicia ichnosp. According to their palaeoecological and sedimentological features, these trace fossils can be divided into 3 ichnoassemblags, ie,①Psilonichnus-Thalassinoides ichnoassemblage, forming in tidal sedimentary environment of Restricted carbonate platform, mainly composed of Psilonichnus ,Thalassinoides, Helminthopsis. ②Helminthopsis-Gordia ichnoassemblage, which is associated with lagoon sedimentary environment of restricted carbonate platform, interbank sea or depression of open carbonate rock platform, mainly composed of Helminthopsis, Gordia, planolites, Palaeophycus, Thalassinoides. ③Chondrites-Scolica ichnoassemblage, which indicates the depression of open carbonate rock platform near the REDOX interface. Finally, depositional model of the Ordovician Majiagou Group and the vertical sedimentary evolution sequence was established based on integrated rock types, rock sequence, sedimentary structure, fossils with trace fossils or ichnoassemblage.
Citation: | NIU YongBin, SHAN TingTing, DONG XiaoBo, ZHOU Shuo, GAO WenXiu. Trace Fossils and Their Sedimentary Environment of Ordovician Majiagou Formation in the North-west of Henan Province[J]. Acta Sedimentologica Sinica, 2015, 33(2): 211-225. doi: 10.14027/j.cnki.cjxb.2015.02.001 |