Second and last age of the Middle Ordovician epoch
The Darriwilian is the upper stage of the Middle Ordovician . It is preceded by the Dapingian and succeeded by the Upper Ordovician Sandbian Stage. The lower boundary of the Darriwilian is defined as the first appearance of the graptolite species Undulograptus austrodentatus around 467.3 million years ago. It lasted for about 8.9 million years until the beginning of the Sandbian around 458.4 million years ago.[ 7] This stage of the Ordovician was marked by the beginning of the Andean-Saharan glaciation .[ 8]
^ Wellman, C.H.; Gray, J. (2000). "The microfossil record of early land plants" . Phil. Trans. R. Soc. B . 355 (1398): 717–732. doi :10.1098/rstb.2000.0612 . PMC 1692785 . PMID 10905606 .
^ Korochantseva, Ekaterina; Trieloff, Mario; Lorenz, Cyrill; Buykin, Alexey; Ivanova, Marina; Schwarz, Winfried; Hopp, Jens; Jessberger, Elmar (2007). "L-chondrite asteroid breakup tied to Ordovician meteorite shower by multiple isochron 40 Ar- 39 Ar dating". Meteoritics & Planetary Science . 42 (1): 113–130. Bibcode :2007M&PS...42..113K . doi :10.1111/j.1945-5100.2007.tb00221.x .
^ Lindskog, A.; Costa, M. M.; Rasmussen, C.M.Ø.; Connelly, J. N.; Eriksson, M. E. (2017-01-24). "Refined Ordovician timescale reveals no link between asteroid breakup and biodiversification" . Nature Communications . 8 : 14066. doi :10.1038/ncomms14066 . ISSN 2041-1723 . PMC 5286199 . PMID 28117834 . It has been suggested that the Middle Ordovician meteorite bombardment played a crucial role in the Great Ordovician Biodiversification Event, but this study shows that the two phenomena were unrelated
^ "International Chronostratigraphic Chart" (PDF) . International Commission on Stratigraphy . September 2023. Retrieved November 10, 2024 .
^ Mitchell, C.; Xu, Chen; Yuan-dong, Zhang; ZhI-hao, Wang; Webby, B.; Finney, S. (September 1997). "Definition of a global boundary stratotype for the Darriwilian Stage of the Ordovician System" . Episodes . 20 (3): 158–166. doi :10.18814/epiiugs/1997/v20i3/003 . Retrieved 13 December 2020 .
^ Bergström, Stig; Finney, S.; Xu, Chen; Pålsson, Christian; Zhi-hao, Wang; Grahn, Yngve (June 2000). "A proposed global boundary stratotype for the base of the Upper Series of the Ordovician System: The Fågelsång section, Scania, southern Sweden" . Episodes . 23 (2): 102–109. doi :10.18814/epiiugs/2000/v23i2/003 . Retrieved 13 December 2020 .
^ "GSSP Table - Paleozoic Era" . Geologic Timescale Foundation. Retrieved 30 November 2012 .
^ Pohl, Alexandre; Donnadieu, Yannick; Le Hir, Guillaume; Ladant, Jean-Baptiste; Dumas, Christophe; Alvarez-Solas, Jorge; Vandenbroucke, Thijs R. A. (28 May 2016). "Glacial onset predated Late Ordovician climate cooling" . Paleoceanography and Paleoclimatology . 31 (6): 800–821. doi :10.1002/2016PA002928 . hdl :1854/LU-8057556 . S2CID 133243759 .