Popigai impact structure
{{Short description|Impact crater in Siberia, Russia}}
{{Other uses|Popigay (disambiguation)}}
{{Infobox terrestrial impact site
| name = Popigai impact structure
| other_name =
| photo = Popigai crater russia.jpg
| photo_size =
| photo_alt =
| photo_caption = Landsat image of Popigai crater
| map = Russia
| map_alt =
| map_caption = Location of the crater in Russia
| map_size =
| location =
| label =
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| coordinates = {{coord|71|39|N|111|11|E|region:RU_type:landmark_scale:1000000|display=inline,title}}
| coordinates_ref =
| confidence = Confirmed
| diameter = {{convert|90|km|mi|abbr=on}}
| depth =
| rise =
| age = 35.7 ± 0.2 Ma
Late Eocene
| exposed = Yes
| drilled = Yes
| imp_size =
| bolide = H chondrite
| translation =
| language =
| pronunciation =
| topo =
| access =
| country = Russia
| state =
| province =
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| municipality =
|region=Krasnoyarsk Krai}}
File:Popigai crater DS1040-1037DA019-024.jpg
The Popigai impact structure is the eroded remnant of an impact crater in northern Siberia, Russia. It is tied with the Acraman impact structure as the fourth largest verified impact structure on Earth.{{cite web|title=Impact Structures listed by Diameter (Increasing) |url=http://www.passc.net/EarthImpactDatabase/New%20website_05-2018/Diametersort.html|publisher=PASSC|access-date=24 April 2025}} A large bolide impact created the {{convert|100|km|mi|-diameter|adj=mid}} crater approximately 35 million years ago during the late Eocene epoch (Priabonian stage).{{Cite journal
|doi = 10.1111/j.1945-5100.2006.tb00985.x
|volume = 41
|pages = 689–703
|last = Deutsch
|first = Alexander
|author2 = Christian Koeberl
|title = Establishing the link between the Chesapeake Bay impact structure and the North American tektite strewn field: The Sr-Nd isotopic evidence
|journal = Meteoritics & Planetary Science
|year = 2006
|issue = 5
|bibcode = 2006M&PS...41..689D
|doi-access= free
| publisher = Springer
| pages = 99–116
| last = Armstrong
| first = Richard |author2=S. Vishnevsky |author3=C. Koeberl
| title = U-Pb Analysis of zircons from the Popigai impact structure, Russia: First Results
| year = 2003
| url = https://books.google.com/books?id=mLfsNALR19oC&q=Popigai+Chesapeake+age&pg=PA109
| isbn = 978-3-540-43517-4
}} It might be linked to the Eocene–Oligocene extinction event.{{cite web|title=Russia's Popigai Meteor Crash Linked to Mass Extinction|website=Live Science |url=http://www.livescience.com/46312-popigai-crater-linked-eocene-mass-extinction.html|date=June 13, 2014}}
The structure is {{convert|300|km|mi|abbr=on}} east from the outpost of Khatanga and {{convert|880|km|mi|abbr=on}} northeast of the city of Norilsk, NNE of the Anabar Plateau. It is designated by UNESCO as a Geopark, a site of special geological heritage.{{Cite journal
|volume = 23
|pages = 3–12
|last = Deutsch
|first = Alexander
|author2 = V.L. Masaitis
|author3 = F. Langenhorst
|author4 = R.A.F. Grieve
|title = Popigai, Siberia—well preserved giant impact structure, national treasury, and world's geological heritage
|journal = Episodes
|year = 2000
|issue = 1
|doi = 10.18814/epiiugs/2000/v23i1/002
|doi-access= free
}} There is a small possibility that the Popigai impact crater may have formed simultaneously with the approximately 35-million-year-old Chesapeake Bay and Toms Canyon impact craters.
For decades, the Popigai impact structure has fascinated paleontologists and geologists, but the entire area was completely off limits because of the diamonds found there. However, a major investigatory expedition was undertaken in 1997, which greatly advanced understanding of the structure. The impactor is suggested to have been a H chondrite asteroid based on ejecta layers from Italy, with the impactor thought to have been several kilometres in diameter.{{Cite journal |last1=Schmitz |first1=Birger |last2=Boschi |first2=Samuele |last3=Cronholm |first3=Anders |last4=Heck |first4=Philipp R. |last5=Monechi |first5=Simonetta |last6=Montanari |first6=Alessandro |last7=Terfelt |first7=Fredrik |date=September 2015 |title=Fragments of Late Eocene Earth-impacting asteroids linked to disturbance of asteroid belt |journal=Earth and Planetary Science Letters |language=en |volume=425 |pages=77–83 |doi=10.1016/j.epsl.2015.05.041 |doi-access=free|bibcode=2015E&PSL.425...77S }}
The shock pressures from the impact instantaneously transformed graphite in the ground into diamonds within a {{convert|13.6|km|mi|abbr=on}} radius of the impact point. These diamonds are usually {{convert|0.5|to|2|mm|in|abbr=on}} in diameter, though a few exceptional specimens are {{convert|10|mm|in|abbr=on}} in size. The diamonds inherited the tabular shape of the original graphite grains and also the original crystals' delicate striations.
Diamond deposits
File:Popigai nanodiamonds.jpg agglomerates.{{cite journal|doi=10.1038/srep14702|pmid=26424384|pmc=4589680|title=Natural occurrence of pure nano-polycrystalline diamond from impact crater|journal=Scientific Reports|volume=5|pages=14702|year=2015|last1=Ohfuji|first1=Hiroaki|last2=Irifune|first2=Tetsuo|last3=Litasov|first3=Konstantin D.|last4=Yamashita|first4=Tomoharu|last5=Isobe|first5=Futoshi|last6=Afanasiev|first6=Valentin P.|last7=Pokhilenko|first7=Nikolai P.|bibcode=2015NatSR...514702O}}]]
Most modern industrial diamonds are produced synthetically. The diamond deposits at Popigai have not been mined because of the remote location and lack of infrastructure, and are unlikely to be competitive with synthetic diamonds.{{cite news|title=Diamonds Beneath the Popigai Crater -- Northern Russia|url=http://geology.com/articles/popigai-crater-diamonds/|access-date=24 September 2012|date=23 September 2012|publisher=geology.com}} Many of the diamonds at Popigai contain crystalline lonsdaleite, an allotrope of carbon that has a hexagonal lattice.{{cite news|title=Russia declassifies deposit of impact diamonds|url=http://pda.itar-tass.com/en/c154/521362.html|publisher=ITAR-TASS|access-date=17 September 2012|date=17 September 2012|archive-url=https://web.archive.org/web/20120920221513/http://pda.itar-tass.com/en/c154/521362.html|archive-date=20 September 2012|url-status=dead}} Pure, laboratory-created lonsdaleite is up to 58% harder than ordinary diamonds.{{cite journal|author1=Pan, Zicheng |author2=Sun, Hong |author3=Zhang, Yi |author4=Chen, Changfeng |name-list-style=amp |title=Harder than Diamond: Superior Indentation Strength of Wurtzite BN and Lonsdaleite |journal=Physical Review Letters|issue= 5|pages=055503|year=2009 |doi= 10.1103/PhysRevLett.102.055503|volume=102|pmid=19257519|bibcode=2009PhRvL.102e5503P}}
- {{cite news |author=Lisa Zyga |date=12 February 2009 |title=Scientists Discover Material Harder Than Diamond |work=Phys.org |url=http://www.physorg.com/news153658987.html}} These types of diamonds are known as "impact diamonds" because they are thought to be produced when a meteorite strikes a graphite deposit at high velocity. They may have industrial uses but are unsuitable as gems.[http://www.rough-polished.com/en/digest/68330.html Pros and cons of extraterrestrial diamonds] {{Webarchive|url=https://web.archive.org/web/20141222224902/http://www.rough-polished.com/en/digest/68330.html |date=2014-12-22 }}, from "Rough&Polished–information and analytics on diamond and jewellery markets."
Additionally, carbon polymorphs, a combination of diamond and lonsdaleite even harder than pure lonsdaleite, have been discovered in the crater.{{cite journal |doi=10.1016/j.crte.2003.07.001|title=A new natural, super-hard, transparent polymorph of carbon from the Popigai impact crater, Russia|journal=Comptes Rendus Geoscience|volume=335|issue=12|pages=889|year=2003|last1=El Goresy|first1=Ahmed|last2=Dubrovinsky|first2=Leonid S|last3=Gillet|first3=Philippe|last4=Mostefaoui|first4=Smail|last5=Graup|first5=Günther|last6=Drakopoulos|first6=Michael|last7=Simionovici|first7=Alexandre S|last8=Swamy|first8=Varghese|last9=Masaitis|first9=Victor L|bibcode=2003CRGeo.335..889E|url=https://comptes-rendus.academie-sciences.fr/geoscience/articles/10.1016/j.crte.2003.07.001/ }}{{Cite journal|last1=Baek|first1=Woohyeon|last2=Gromilov|first2=Sergey A.|last3=Kuklin|first3=Artem V.|last4=Kovaleva|first4=Evgenia A.|last5=Fedorov|first5=Alexandr S.|last6=Sukhikh|first6=Alexander S.|last7=Hanfland|first7=Michael|last8=Pomogaev|first8=Vladimir A.|last9=Melchakova|first9=Iuliia A.|last10=Avramov|first10=Paul V.|last11=Yusenko|first11=Kirill V.|date=2019-03-13|title=Unique Nanomechanical Properties of Diamond–Lonsdaleite Biphases: Combined Experimental and Theoretical Consideration of Popigai Impact Diamonds|journal=Nano Letters|volume=19|issue=3|pages=1570–1576|doi=10.1021/acs.nanolett.8b04421|pmid=30735045|bibcode=2019NanoL..19.1570B|s2cid=73443676 |issn=1530-6984}}
See also
- List of impact craters on Earth
- List of possible impact structures on Earth
- {{annotated link|Logancha crater}}
References
{{Reflist}}
External links
- [https://www.unb.ca/passc/ImpactDatabase/ Earth Impact Database]
- [https://web.archive.org/web/20100627071048/http://geology.mines.edu/faculty/Klee/Popigai.pdf About the Popigai impact structure]
- [http://unesdoc.unesco.org/images/0015/001500/150007e.pdf UNESCO Global Geopark Network]
- [https://maps.google.com/maps?q=71.661935,+110.960998&num=1&t=h&vpsrc=6&ie=UTF8&ll=70.670881,99.316406&spn=31.51452,173.144531&z=3&iwloc=A Google Maps]
{{Impact cratering on Earth}}
{{Authority control}}
Category:Impact craters of Russia
Category:Impact craters of the Arctic
Category:Eocene impact craters
Category:Landforms of Krasnoyarsk Krai