Mirovia

{{short description|Hypothesized superocean surrounding the supercontinent Rodinia in the Neoproterozoic Era}}

Mirovia or Mirovoi (from Russian мировой, mirovoy, meaning "global") was a hypothesized superocean which may have been a global ocean surrounding the supercontinent Rodinia in the Neoproterozoic Era, about 1 billion to 750 million years ago.{{Cite book |last=McMenamin |first=Mark A. |first2=Dianna L. |last2=McMenamin |year=1990 |chapter=The Rifting of Rodinia |title=The Emergence of Animals |publisher=Columbia University Press |isbn=978-0-231-06647-1 |chapter-url-access=registration |chapter-url=https://archive.org/details/emergenceofanima00mcme }} Mirovia may be essentially identical to, or the precursor of, the hypothesized Pan-African Ocean, which followed the rifting of Rodinia. The Panthalassa (proto-Pacific) Ocean developed in the Neoproterozoic Era by subduction at the expense of the global Mirovia ocean.{{Cite book |last=Powell |first=Christopher McA |last2=Pisarevsky |first2=Sergei A. |chapter=Rodinia to Gondwanaland: Growth of the Pacific Ocean and Destruction of the Mozambique and Brazilide Oceans |title=GSA Conference, Earth System Processes - Global Meeting (June 24-28, 2001), abstract |chapter-url=http://gsa.confex.com/gsa/2001ESP/finalprogram/abstract_8026.htm |access-date=2007-07-10 |archive-date=2011-08-09 |archive-url=https://web.archive.org/web/20110809024236/http://gsa.confex.com/gsa/2001ESP/finalprogram/abstract_8026.htm |url-status=dead }}

Geologic evidence suggests that the middle Neoproterozoic, the Cryogenian period, was an extreme ice age so intense that Mirovia may have been completely frozen to a depth of 2 km. This is part of the Snowball Earth hypothesis.{{Cite journal |last1=Dutkiewicz |first1=A. |last2=Merdith |first2=A. S. |last3=Collins |first3=A. S. |last4=Mather |first4=B. |last5=Ilano |first5=L. |last6=Zahirovic |first6=S. |last7=Dietmar Müller |first7=R. |year=2024 |title=Duration of Sturtian 'Snowball Earth' glaciation linked to exceptionally low mid-ocean ridge outgassing |journal=Geology |doi=10.1130/G51669.1 |doi-access=free |hdl=2440/140615 |hdl-access=free }}