{{Short description|Geologic formation in China}} {{infobox rockunit | age = Ediacaran<br>{{Geological range|635|577|602 ± 7 – 577 Mya|refs = <ref name="age" />}} | period = Ediacaran | location = Anhui | country = {{CHN}} }}
The '''Lantian Formation''' is a 150-meter-thick sequence of rocks deposited in Xiuning County, Anhui Province in southern China during a 90-million-year epoch in the Ediacaran period.<ref name="Narbonne2011">{{Cite journal | last1 = Narbonne | first1 = G. M. | title = Evolutionary biology: when life got big | journal = Nature | volume = 470 | pages = 339–40 | year = 2011 | doi = 10.1038/470339a | pmid = 21331031 |bibcode = 2011Natur.470..339N | issue=7334| s2cid = 205062340 }}</ref> Its algal macrofossils (which have alternatively been interpreted as putative metazoans<ref name="WanYuan2016">{{cite journal|last1=Wan|first1=Bin|last2=Yuan|first2=Xunlai|last3=Chen|first3=Zhe|last4=Guan|first4=Chengguo|last5=Pang|first5=Ke|last6=Tang|first6=Qing|last7=Xiao|first7=Shuhai|last8=McIlroy|first8=Duncan|title=Systematic description of putative animal fossils from the early Ediacaran Lantian Formation of South China|journal=Palaeontology|volume=59|issue=4|year=2016|pages=515–532|issn=0031-0239|doi=10.1111/pala.12242|doi-access=free|bibcode=2016Palgy..59..515W }}</ref>) are the oldest large and complex fossils known.<ref name="Narbonne2011" />
== Sedimentology == The rocks were deposited in shallow seas, in the photic zone yet below storm wave base,{{clarify|date=November 2013}}<ref name="Yuan2011">{{Cite journal | doi = 10.1038/nature09810 | last1 = Yuan | first1 = X. | last2 = Chen | first2 = Z. | last3 = Xiao | first3 = S. | last4 = Zhou | first4 = C. | last5 = Hua | first5 = H. | title = An early Ediacaran assemblage of macroscopic and morphologically differentiated eukaryotes | journal = Nature | volume = 470 | issue = 7334 | pages = 390–3 | year = 2011 | pmid = 21331041|bibcode = 2011Natur.470..390Y | s2cid = 205224028 }}</ref> yet were deposited in predominantly anoxic conditions. The fossils are located on the bedding planes, and are randomly oriented.<ref name=Narbonne2011 />
The lowest part of the formation consists of a cap dolomite, marking the end of the Marinoan glaciation and start of the Ediacaran. Above this is black shale containing the Lantian biota fossils. Above this are layers of dolomite, and shale followed by limestone. The highest part of the formation is black shale again. Above the formation is the Piyuancun formation consisting of silicious rock. The Lantian formation overlies diamictite from the Cryogenian.<ref>[http://www.nature.com/nature/journal/v470/n7334/extref/nature09810-s1.pdf supplementary figure 4 of] {{doi|10.1038/nature09810}}</ref>
== Taphonomy == The fossils are preserved as carbonaceous films in a Burgess Shale type preservational fashion.<ref name=Narbonne2011 /> ''Anhuiphyton lineatum'' is one example of a fossil located in the site. [[File:Flabellophyton lantianense.png|150px|thumb|alt=Flabellophyton lantianense|A reconstruction of ''Flabellophyton'' from the Lantian Formation.]]
== Age == Originally presumed to be Cambrian in age,<ref name=Narbonne2011 /> the formation is now correlated with the Doushantuo Formation, with an overlying formation also falling in the Ediacaran period.<ref name="Yuan2011" />
The Lantian biota has a maximum Re-Os age of {{Ma|602|error=7}}.<ref name="age">{{Cite journal|doi=10.1130/G49734.1|title=Implications for Ediacaran biological evolution from the ca. 602 Ma Lantian biota in China|year=2022|last1=Yang|first1=Chuan|last2=Li|first2=Yang|last3=Selby|first3=David|last4=Wan|first4=Bin|last5=Guan|first5=Chengguo|last6=Zhou|first6=Chuanming|last7=Li|first7=Xian-Hua|journal=Geology|volume=50 |issue=5 |pages=562–566 |s2cid=246788576|doi-access=free|bibcode=2022Geo....50..562Y }}</ref>
== References == {{reflist}}
Category:Ediacaran Asia Category:Ediacaran life Category:Ediacaran geology Category:Proterozoic Eonothem of Asia