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The Khatyspyt Formation of the Olenek Uplift is unusual in preserving Ediacara-type organisms by means of both authigenic carbonate cementation within bituminous limestones (Xiao et al. 2005; Grazhdankin et al. 2008), as well as carbonaceous impressions on calcitic mudstones and shales (Rogov et al. 2012). Neither of these two taphonomic windows are commonly seen in Ediacaran deposits elsewhere, and they reveal an abundant biota including possible microbial colonies, multicellular algae, and potential metazoans (Grazhdankin et al. 2008).
Also unusual here is the presence of stromatolites, along with vendotaenids, acritarchs, and some ichnofossils (Sokolov and Iwanovski 1985; Knoll et al. 1995). This site thus offers one of the most ecologically and taphonomically diverse Ediacaran fossil assemblages. There is considerable potential for future discoveries. |
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Khorbusuonka River (Khatyspyt Fm.), Olenek Uplift
The fossil-bearing sedimentary sections lie on the banks of the Khorbusuonka River (the right tributary of the Olenek River), Bulunsky District, Olenek Uplift, Siberian Republic of Sakha, northern Yakutia, Russia. The settlement of Tiksi is ~200 km to the East. Outcrops are found along the 44 km of riverbank between the mouths of the Khayalakh and Uesya-Uettyakh Creeks. This remote part of Russia is challenging to access, and can only be reached as part of an organised research expedition.
Stratigraphy, age and palaeoenvironmental interpretation
Fossils are found within the Khatyspyt Formation of the Khorbusuonka Group, in limestones considered to represent a deep-water carbonate ramp setting (Knoll et al. 1995). Around 440 metres of stratigraphy is currently documented from the site, including the Maastakh, Khatyspyt and Turkut Formations, passing up into the Lower Cambrian fossil-bearing Kessyusa Group (Nagovitsin et al. 2015). The site has, for the most part, been correlated with other Ediacaran regions in Russia on the basis of chemostratigraphy (e.g. Knoll et al. 1995; Pelechaty 1998). A U-Pb radiometric date of 543.9 Ma has been obtained from ~100 m above those horizons bearing Ediacara-type fossils (Bowring et al. 1993).
Key references
Sokolov and Iwanowski 1985; Bowring et al. 1993; Knoll et al. 1995; Pelechaty 1998; Dzik 2003; Xiao et al. 2005; McCall 2006; Grazhdankin et al. 2008; Rogov et al. 2012
The fossil-bearing sedimentary sections lie on the banks of the Khorbusuonka River (the right tributary of the Olenek River), Bulunsky District, Olenek Uplift, Siberian Republic of Sakha, northern Yakutia, Russia. The settlement of Tiksi is ~200 km to the East. Outcrops are found along the 44 km of riverbank between the mouths of the Khayalakh and Uesya-Uettyakh Creeks. This remote part of Russia is challenging to access, and can only be reached as part of an organised research expedition.
Stratigraphy, age and palaeoenvironmental interpretation
Fossils are found within the Khatyspyt Formation of the Khorbusuonka Group, in limestones considered to represent a deep-water carbonate ramp setting (Knoll et al. 1995). Around 440 metres of stratigraphy is currently documented from the site, including the Maastakh, Khatyspyt and Turkut Formations, passing up into the Lower Cambrian fossil-bearing Kessyusa Group (Nagovitsin et al. 2015). The site has, for the most part, been correlated with other Ediacaran regions in Russia on the basis of chemostratigraphy (e.g. Knoll et al. 1995; Pelechaty 1998). A U-Pb radiometric date of 543.9 Ma has been obtained from ~100 m above those horizons bearing Ediacara-type fossils (Bowring et al. 1993).
Key references
Sokolov and Iwanowski 1985; Bowring et al. 1993; Knoll et al. 1995; Pelechaty 1998; Dzik 2003; Xiao et al. 2005; McCall 2006; Grazhdankin et al. 2008; Rogov et al. 2012
