The Vaalbara continent, a continent dating from 2.7 to 3.6 billion years ago
Chronology
−3600 —
–
−3550 —
–
−3500 —
–
−3450 —
–
−3400 —
–
−3350 —
–
−3300 —
–
−3250 —
–
−3200 —
–
A r c h e a n
Eoarchean
Paleoarchean
Mesoarchean
←
Earliest definitive Stromatolites and uncontroversial life forms
←
First photosynthetic organisms appeared[1]
Events of the Paleoarchean. Axis scale: millions of years ago.
Proposed redefinition(s)
4031–3490 Ma Gradstein et al., 2012
Proposed subdivisions
Acastan Period, 4031–3810 Ma
Gradstein et al., 2012 Isuan Period, 3810–3490 Ma
Gradstein et al., 2012
Etymology
Name formality
Formal
Alternate spelling(s)
Palaeoarchaean
Synonym(s)
Early Archean
Usage information
Celestial body
Earth
Regional usage
Global (ICS)
Time scale(s) used
ICS Time Scale
Definition
Chronological unit
Era
Stratigraphic unit
Erathem
Time span formality
Formal
Lower boundary definition
Defined Chronometrically
Lower GSSA ratified
1991[citation needed]
Upper boundary definition
Defined Chronometrically
Upper GSSA ratified
1991[citation needed]
The Paleoarchean (/ˌpeɪlioʊ.ɑːrˈkiːən,ˌpæl-/PAY-lee-oh-ar-KEE-ən, PAL-), also spelled Palaeoarchaean (formerly known as the early Archean), is a geologic era within the Archean Eon. The name derives from Greek "Palaios" ancient. It spans the period of time 3,600 to 3,200 million years ago. The era is defined chronometrically and is not referenced to a specific level of a rock section on Earth. The earliest confirmed evidence of life comes from this era, and Vaalbara, one of Earth's earliest supercontinents, may have formed during this era.[2][3]
^Caredona, Tanai (6 March 2018). "Early Archean origin of heterodimeric Photosystem I". Heliyon. 4 (3): e00548. doi:10.1016/j.heliyon.2018.e00548. PMC 5857716. PMID 29560463. Retrieved 25 February 2021.
^Lepot, Kevin (2020). "Signatures of early microbial life from the Archean (4 to 2.5 Ga) eon". Earth-Science Reviews. 209: 103296. Bibcode:2020ESRv..20903296L. doi:10.1016/j.earscirev.2020.103296. hdl:20.500.12210/62415. ISSN 0012-8252. S2CID 225413847.
^Bradley, Kyle; Weiss, Benjamin P.; Buick, Roger (2015). "Records of geomagnetism, climate, and tectonics across a Paleoarchean erosion surface". Earth and Planetary Science Letters. 419: 1–13. Bibcode:2015E&PSL.419....1B. doi:10.1016/j.epsl.2015.03.008. ISSN 0012-821X.
The Paleoarchean (/ˌpeɪlioʊ.ɑːrˈkiːən, ˌpæl-/ PAY-lee-oh-ar-KEE-ən, PAL-), also spelled Palaeoarchaean (formerly known as the early Archean), is a geologic...
million years, from the end of the Hadean Eon 4031 Mya to the start of the Paleoarchean Era 3600 Mya. The beginnings of life on Earth have been dated to this...
ago, and the Eoarchean, starting 4 billion years ago, and part of the Paleoarchean era, starting 3.6 billion years ago, of the Archean eon. This period...
chronostratigraphic erathem. There are ten defined eras: the Eoarchean, Paleoarchean, Mesoarchean, Neoarchean, Paleoproterozoic, Mesoproterozoic, Neoproterozoic...
Kaapval craton begins: old tonaltic gneisses laid down c. 3,600 Ma – Paleoarchean Era starts. Possible assembly of the Vaalbara supercontinent; oldest...
estimates of the LUCA's age ranged from 3.5 to 3.8 billion years ago in the Paleoarchean, a few hundred million years before the earliest fossil evidence of life...
form of photosynthesis that evolved on Earth, going back as far as the Paleoarchean, preceding that of cyanobacteria (see Purple Earth hypothesis). While...
and eonothem are divided similarly into the Neoarchean, Mesoarchean, Paleoarchean and the Eoarchean, for which a lower (oldest) limit is undefined. Body...
Earth, estimated to have lived some 3.5 to 3.8 billion years ago (in the Paleoarchean). The project of a complete description of the phylogenetic relationships...
might be present in the western part of Eastern Block as well. The rare Paleoarchean rocks are located in Anshan and eastern Hebei, composed of granitoids...
D.; Strauss, H.; Schäfer, N.; Reitner, J. (2016). "A Rare Glimpse of Paleoarchean Life: Geobiology of an Exceptionally Preserved Microbial Mat Facies from...
Global Information