Weeks Formation

{{Short description|Geologic formation in Utah, United States}}

{{Infobox rockunit

| name = Weeks Formation

| image = Beckwithia cephalon collection Paul Hille.jpg

| caption = Fossil from the Weeks Formation

| type = Formation

| age = {{fossilrange|Guzhangian}}

| period = Guzhangian

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| region = Utah

| country = United States

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The Weeks Formation is a geologic formation in Utah. It preserves fossils dating back to the Cambrian period and more specifically the Guzhangian stage. Its upper part has yielded a diverse fauna dominated by trilobites and brachiopods, but also comprising various soft-bodied organisms, such as Falcatamacaris.{{Cite journal|last=Lerosey-Aubril|first=Rudy|last2=Gaines|first2=Robert R.|last3=Hegna|first3=Thomas A.|last4=Ortega-Hernández|first4=Javier|last5=Van Roy|first5=Peter|last6=Kier|first6=Carlo|last7=Bonino|first7=Enrico|date=2018|title=The Weeks Formation Konservat-Lagerstätte and the evolutionary transition of Cambrian marine life|url=https://jgs.lyellcollection.org/content/175/5/705/tab-article-info|journal=Journal of the Geological Society|volume=175|pages=705–715|doi=10.1144/jgs2018-042 |url-access=subscription}} As such, it is regarded as a Konservat-Lagerstätte.