Paleoarchean - Mashpedia All-in-One Encyclopedia

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Stromatolites - Pilbara craton - Western Australia

The Paleoarchean (pron.: /ˌpeɪlɪ.oʊ.ɑrˈkiːən/; also spelled Palaeoarchaean) is a geologic era within the Archaean. It spans the period of time 3,600 to 3,200 million years ago—the period being defined chronometrically and not referenced to a specific level in a rock section on Earth. The name derives from Greek "Palaios" ancient. The oldest ascertained life form (well-preserved bacteria older than 3,460 million years found in Western Australia) is from this period. The 1st supercontinent Vaalbara formed during this period.

Archean Eon
Eoarchean	Paleoarchean	Mesoarchean	Neoarchean

Geologic history of Earth

Precambrian supereon (4.567 Gya – 541 Mya)

In left column are eons; right column: bold are eras; not bold are periods:

Hadean (4.567 – 4 Gya)	Chaotian (4.567 - 4.4 Gya) Zirconian (4.4 - 4 Gya)

Archean (4 – 2.5 Gya)	Eoarchean (4 – 3.6 Gya) Paleoarchean (3.6 – 3.2 Gya) Mesoarchean (3.2 – 2.8 Gya) Neoarchean (2.8 – 2.5 Gya)

Proterozoic (2.5 Gya – 541 Mya)	Paleoproterozoic (2.5 – 1.6 Gya): Siderian (2.5 – 2.3 Gya) · Rhyacian (2.3 – 2.05 Gya) · Orosirian (2.05 – 1.8 Gya) · Statherian (1.8 – 1.6 Gya) Mesoproterozoic (1.6 – 1 Gya): Calymmian (1.6 – 1.4 Gya) · Ectasian (1.4 – 1.2 Gya) · Stenian (1.2 – 1 Gya) Neoproterozoic (1 Gya – 541 Mya): Tonian (1 Gya – 850 Mya) · Cryogenian (850 – 635 Mya) · Ediacaran (635 – 541 Mya)

Mya = millions years ago. Gya = billions years ago.

Phanerozoic eon (541.0 – 0 Mya)

In horizontal bars are eras; in left column are periods; right column: bold are epochs; not bold not italic are ages; italic are chrons:

Paleozoic (541.0 – 252.2 Mya)

Cambrian (541.0 – 485.4 Mya)	Terreneuvian (541.0 – 521 Mya): Fortunian (541.0 – 529 Mya) · Age 2* (529 – 521 Mya) *Epoch 2 (521 – 509 Mya)*: Age 3 (521 – 514 Mya) · Age 4* (514 – 509 Mya) *Epoch 3 (509 – 497 Mya)*: Age 5 (509 – 504.5 Mya) · Drumian (504.5 – 500.5 Mya) · Guzhangian (500.5 – 497 Mya) Furongian (497 – 485.4 Mya): Paibian (497 – 494 Mya) · Jiangshanian (494 – 489.5 Mya) · Age 10* (489.5 – 485.4 Mya)

Ordovician (485.4 – 443.4 Mya)	Lower Ordovician (485.4 – 470.0 Mya): Tremadocian (485.4 – 477.7 Mya) · Floian (477.7 – 470.0 Mya) Middle Ordovician (470.0 – 458.4 Mya): Dapingian (470.0 – 467.3 Mya) · Darriwilian (467.3 – 458.4 Mya) Upper Ordovician (458.4 – 443.4 Mya): Sandbian (458.4 – 453.0 Mya) · Katian (453.0 – 445.2 Mya) · Hirnantian (445.2 – 443.4 Mya)

Silurian (443.4 – 419.2 Mya)	Llandovery (443.4 – 433.4 Mya): Rhuddanian (443.4 – 440.8 Mya) · Aeronian (440.8 – 438.5 Mya) · Telychian (438.5 – 433.4 Mya) Wenlock (433.4 – 427.4 Mya): Sheinwoodian (433.4 – 430.5 Mya) · Homerian (430.5 – 427.4 Mya) Ludlow (427.4 – 423.0 Mya): Gorstian (427.4 – 425.6 Mya) · Ludfordian (425.6 – 423.0 Mya) Pridoli (423.0 – 419.2 Mya)

Devonian (419.2 – 358.9 Mya)	Lower Devonian (419.2 – 393.3 Mya): Lochkovian (419.2 – 410.8 Mya) · Pragian (410.8 – 407.6 Mya) · Emsian (407.6 – 393.3 Mya) Middle Devonian (393.3 – 382.7 Mya): Eifelian (393.3 – 387.7 Mya) · Givetian (387.7 – 382.7 Mya) Upper Devonian (382.7 – 358.9 Mya): Frasnian (382.7 – 372.2 Mya) · Famennian (372.2 – 358.9 Mya)

Carboniferous (358.9 – 298.9 Mya)	Mississippian (358.9 – 323.2 Mya): Tournaisian (358.9 – 346.7 Mya) · Viséan (346.7 – 330.9 Mya) · Serpukhovian (330.9 – 323.2 Mya) Pennsylvanian (323.2 – 298.9 Mya): Bashkirian (323.2 – 315.2 Mya) · Moscovian (315.2 – 307.0 Mya) · Kasimovian (307.0 – 303.7 Mya) · Gzhelian (303.7 – 298.9 Mya)

Permian (298.9 – 252.2 Mya)	Cisuralian (298.9 – 272.3 Mya): Asselian (298.9 – 295.5 Mya) · Sakmarian (295.5 – 290.1 Mya) · Artinskian (290.1 – 279.3 Mya) · Kungurian (279.3 – 272.3 Mya) Guadalupian (272.3 – 259.9 Mya): Roadian (272.3 – 268.8 Mya) · Wordian (268.8 – 265.1 Mya) · Capitanian (265.1 – 259.9 Mya) Lopingian (259.9 – 252.2 Mya): Wuchiapingian (259.9 – 254.2 Mya) · Changhsingian (254.2 – 252.2 Mya)

Mesozoic (252.2 – 66.0 Mya)

Triassic (252.2 – 201.3 Mya)	Lower Triassic (252.2 – 247.2 Mya): Induan (252.2 – 251.2 Mya) · Olenekian (251.2 – 247.2 Mya) Middle Triassic (247.2 – 235 Mya): Anisian (247.2 – 242 Mya) · Ladinian (242 – 235 Mya) Upper Triassic (235 – 201.3 Mya): Carnian (235 – 228 Mya) · Norian (228 – 208.5 Mya) · Rhaetian (208.5 – 201.3 Mya)

Jurassic (201.3 – 145.0 Mya)	Lower Jurassic (201.3 – 174.1 Mya): Hettangian (201.3 – 199.3 Mya) · Sinemurian (199.3 – 190.8 Mya) · Pliensbachian (190.8 – 182.7 Mya) · Toarcian (182.7 – 174.1 Mya) Middle Jurassic (174.1 – 163.5 Mya): Aalenian (174.1 – 170.3 Mya) · Bajocian (170.3 – 168.3 Mya) · Bathonian (168.3 – 166.1 Mya) · Callovian (166.1 – 163.5 Mya) Upper Jurassic (163.5 – 145.0 Mya): Oxfordian (163.5 – 157.3 Mya) · Kimmeridgian (157.3 – 152.1 Mya) · Tithonian (152.1 – 145.0 Mya)

Cretaceous (145.0 – 66.0 Mya)	Lower Cretaceous (145.0 – 100.5 Mya): Berriasian (145.0 – 139.8 Mya) · Valanginian (139.8 – 132.9 Mya) · Hauterivian (132.9 – 129.4 Mya) · Barremian (129.4 – 125.0 Mya) · Aptian (125.0 – 113.0 Mya) · Albian (113.0 – 100.5 Mya) Upper Cretaceous (100.5 – 66.0 Mya): Cenomanian (100.5 – 93.9 Mya) · Turonian (93.9 – 89.8 Mya) · Coniacian (89.8 – 86.3 Mya) · Santonian (86.3 – 83.6 Mya) · Campanian (83.6 – 72.1 Mya) · Maastrichtian (72.1 – 66.0 Mya)

Cenozoic (66.0 – 0 Mya)

Paleogene, Neogene and early Pleistocene comprise former Tertiary* (66.0 – 1.8 Mya) period. Gelasian and Calabrian comprise Early Pleistocene (2.588 Mya – 781 kya) subepoch.

Paleogene (66.0 – 23.03 Mya)	Paleocene (66.0 – 56.0 Mya): Danian (66.0 – 61.6 Mya) · Selandian (61.6 – 59.2 Mya) · Thanetian (59.2 – 56.0 Mya) Eocene (56.0 – 33.9 Mya): Ypresian (56.0 – 47.8 Mya) · Lutetian (47.8 – 41.3 Mya) · Bartonian (41.3 – 38.0 Mya) · Priabonian (38.0 – 33.9 Mya) Oligocene (33.9 – 23.03 Mya): Rupelian (33.9 – 28.1 Mya) · Chattian (28.1 – 23.03 Mya)

Neogene (23.03 – 2.588 Mya)	Miocene (23.03 – 5.333 Mya): Aquitanian (23.03 – 20.44 Mya) · Burdigalian (20.44 – 15.97 Mya) · Langhian (15.97 – 13.82 Mya) · Serravallian (13.82 – 11.62 Mya) · Tortonian (11.62 – 7.246 Mya) · Messinian (7.246 – 5.333 Mya) Pliocene (5.333 – 2.588 Mya): Piacenzian (5.333 – 3.600 Mya) · Zanclean (3.600 – 2.588 Mya)

Quaternary (2.588 – 0 Mya)	Pleistocene (2.588 Mya – 11.7 kya): Gelasian (2.588 – 1.806 Mya) · Calabrian (1.806 Mya – 781 kya) · Middle Pleistocene / Ionian (781 – 126 kya) · Late Pleistocene / Tarantian (126 – 11.7 kya): Oldest Dryas (18 – 14.67 kya) · Bølling* (14.67 – 14 kya) · Older Dryas* (14 – 13.7 kya) · Allerød* (13.7 – 12.8 kya) · Younger Dryas* (12.8 – 11.7 kya)* Holocene (11.7 – 0 kya): Preboreal (11.7 – 9 kya) · Boreal* (9 – 8 kya) · Atlantic* (8 – 5 kya) · Subboreal* (5 – 2.5 kya) · Subatlantic* (2.5 – 0 kya)*