- Paleozoic
starts shortly after the breakup of a supercontinent called Pannotia and at the end of the global Cryogenian ... more details
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- Proterozoic
Geological eon Image Stromatolites Cochabamba.jpg thumb right Lower Proterozoic Stromatolites from Bolivia, South America The Proterozoic IPAc en icon p r o t r z o . k is a eon geology geological eon representing the time just before the proliferation of complex life on Earth . The name Proterozoic comes from Greek and means earlier life . The Proterozoic Eon extended from val 2500 ul Ma to val 542.0 1.0 u Ma million years ago , and is the most recent part of the informally named Precambrian time. It is subdivided into three geologic era geology era s from oldest to youngest the Paleoproterozoic , Mesoproterozoic , and Neoproterozoic . The well identified events of this eon were the transition to an oxygen ated atmosphere during the Mesoproterozoic several glacier glaciations , including the hypothesized Snowball Earth during the Cryogenian period in the late Neoproterozoic and the Ediacaran Period 635 to 542 Ma which is characterized by the evolution of abundant soft bodied multicellular organisms. The Proterozoic record The geologic record of the Proterozoic is much better than that for the preceding Archean . In contrast to the deep water deposits of the Archean, the Proterozoic features many stratum strata that were laid down in extensive shallow Epeiric Sea epicontinental seas furthermore, many of these rocks are less Metamorphic rock metamorphosed than Archean age ones, and plenty are unaltered. ref cite book last Stanley first Steven M. title Earth System History location New York publisher W.H. Freeman and Company year 1999 isbn 0 7167 2882 6 pages 315 ref Study of these rocks shows that the eon continued the massive continent al accretion that had begun late in the Archean, as well as featured the first definitive supercontinent cycle s and wholly modern orogeny orogenic activity. ref Stanley, 315 18, 329 32 ref The first known glaciations occurred during the Proterozoic one began shortly after the beginning of the eon, while there were at least ... more details
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- Iapetus Ocean
developed in the northern parts of this supercontinent during the Cryogenian period 850 630 ... more details
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- Precambrian (album)
19 small li ol V. Neoproterozoic ol start 8 li Tonian small 7 18 small li li Cryogenian Instrumental ... more details
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- Ice age
850 to 630 million years ago the Cryogenian period and may have produced a Snowball Earth in which ... cite web author Chris Clowes url http www.palaeos.com Proterozoic Neoproterozoic Cryogenian Snowballs.html ... Cryogenian Snowballs.html archivedate 20 Dec 2010 title Snowball Scenarios of the Cryogenian .... A supercontinent covers most of the equator, as Rodinia did during the Cryogenian period. Since ... more details
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- Geology of Wales
old which puts them within the Cryogenian period. ref http www.museumwales.ac.uk en rhagor article ... more details
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- Precambrian
the Ediacaran fauna appeared. Cryogenian The middle period in the Neoproterozoic Era 950 630 ... more details
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- Geology of Jersey
Image Jerseyt geological map.png thumb right 300px Geology of Jersey The geology of Jersey is characterised by the Late Proterozoic Brioverian volcanics, the Cadomian Orogeny , and only small signs of later deposits from the Cambrian and Quaternary periods. The kind of rocks go from conglomerate to shale, volcanic, intrusive and plutonic igneous rocks of many compositions, and metamorphic rocks as well, thus including most major types. Brioverian sediments Graphical timeline title Jersey Geological Timeline align right width 20 from 1000 to 0 period1 Tonian period2 Cryogenian period3 Ediacaran period4 Cambrian period5 Ordovician period6 Silurian period7 Devonian period8 Carboniferous period9 Triassic period10 Permian period11 Jurassic period12 Cretaceous period13 Tertiary period14 Quaternary note1 Jersey Volcanic group note1 at 630 note2 end of ice age note2 at .016 note4 Granite in the north west br and north west note4 at 445 note5 Granite in the south west note5 at 515 note7 Cadomian Orogeny note7 at 600 note7 Brioverian Sedimentation note7 at 800 note14 Sturtian glaciation note14 at 725 note6 Variscan Orogeny note6 at 350 bar1 from 700 bar1 to 500 bar1 left 0.8 bar1 right 1 bar1 colour red bar2 from 900 bar2 to 700 bar2 left 0.8 bar2 right 1 bar2 colour brown bar3 from 550 bar3 to 480 bar3 left 0.8 bar3 right 1 bar3 colour pink bar4 from 400 bar4 to 300 bar4 left 0.8 bar4 right 1 bar4 colour cyan bar5 from 465 bar5 to 426 bar5 left 0.8 bar5 right 1 bar5 colour yellow caption An approximate time scale of events br in the Geological history of Jersey . br Axis scale is in millions of years ago. The Brioverian rocks were formed between 900 and 700 mya. They were named after Briov re, the native name for St. L , in Normandy, which is the first area these rocks were described from. They start with turbidite s in the west, centre and south of Jersey, including at Saint Ouen, Jersey St Ouens Bay , and St Aubins Bay. The Brioverian sedimentary rocks are all well bedded ... more details
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- Tunnel valley
. ref name LeHeron2009A Cryogenian BR or Sturtian Varangian 800 635 Cryogenian Neoproterozoic Tunnel valleys have been reported in the Cryogenian strata of Oman and Mauritania. ref name LeHeron2009A ... more details
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- Burgess Shale type preservation
of Riphean stage Riphean Tonian Cryogenian age lagerst tten. ref name Butterfield1995a ... more details
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- Detailed logarithmic timeline
&ndash 800 Ma unit Ma Neoproterozoic era Sturtian Varangian or Cryogenian glaciation begins ... 630 Ma Neoproterozoic Breakup of Rodinia , Sturtian Varangian or Cryogenian glaciation, possible ... more details
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- Timeline of environmental history
ya 1 Ga Evo multicellular life 1.1 Ga Geo Rodinia Supercontinent Forms 800 Ma Clima Cryogenian Ice Age Begins 750 Ma Geo Rodinia Supercontinent Splits 635 Ma Clima Cryogenian Ice Age Ends 600,000,000 ... more details
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- Gaia hypothesis
during the Huronian , Sturtian and Marinoan Cryogenian Varanger Ice Ages the world to very nearly become a solid snowball contradicts the Gaia hypothesis somewhat, although the ending of these Cryogenian ... more details
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- History of the Earth
Ma, in the Cryogenian period geology period . ref cite news url http www.sciencedaily.com releases ... from the break up of Rodinia at about the same time. The Cryogenian period was followed by the Ediacaran ... more details
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- Ediacara biota
years after the end of the Cryogenian glaciations may represent embryonic resting stages in the life ... more details
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- List of geochronologic names
age Pleistocene Netherlands, Great Britain Cromer England Cryogenian 850 635.5 1.2 ref name Hoffmann ... more details
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- Sponge
record the appearance of Demospongiae during the Cryogenian period journal Nature year 2009 ... more details
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