Editing Hadean (section)

==Etymology==
The eon's name "Hadean" comes from [[Hades]], the [[Greek god]] of the [[Greek underworld|underworld]] (whose name is also used to describe the underworld itself), referring to the [[hell]]ish conditions then prevailing on [[early Earth]]: the planet had just been formed from recent [[accretion (astrophysics)|accretion]], and its surface was still molten with superheated [[lava]] due to that, the abundance of short-lived radioactive elements, and frequent [[impact event]]s with other Solar System bodies.

The term was coined by American geologist [[Preston Cloud]], originally to label the period before the earliest known [[rock (geology)|rock]]s on Earth.<ref>{{cite journal |last=Cloud |first=Preston |year=1972 |title=A working model of the primitive Earth |journal=American Journal of Science |volume=272 |issue=6 |pages=537–548 |bibcode=1972AmJS..272..537C |doi=10.2475/ajs.272.6.537}}</ref><ref>{{cite book |last=Bleeker |first=W. |year=2004 |chapter=Chapter&nbsp;10. Toward a 'natural' Precambrian time scale |editor1-last=Gradstein |editor1-first=Felix M. |editor2-last=Ogg |editor2-first=James G. |editor3-last=Smith |editor3-first=Alan G. |title=A Geologic Time Scale |publisher=Cambridge University Press |location=Cambridge, UK |isbn=9780521786737 |page=145 |chapter-url=https://books.google.com/books?id=rse4v1P-f9kC&pg=PA145}}</ref> [[W. Brian Harland|W.B. Harland]] later coined an almost synonymous term, the '''Priscoan period''', from ''priscus'', a Latin word for 'ancient'.<ref>{{cite encyclopedia |title=Priscoan |dictionary=Oxford Living dictionaries |url=https://en.oxforddictionaries.com/definition/priscoan |url-status=dead |archive-url=https://web.archive.org/web/20181129225130/https://en.oxforddictionaries.com/definition/priscoan |archive-date=2018-11-29}}</ref> Other, older texts refer to the eon as the '''Pre-Archean'''.<ref>{{cite conference |last=Shaw |first=D.M. |year=1975 |title=Early history of the Earth |conference=Proceedings of the NATO Advanced Study Institute |publisher=John Wiley |location=Leicester |isbn=0-471-01488-5 |pages=33–53}}</ref><ref>{{cite journal |last1=Jarvis |first1=Gary T. |last2=Campbell |first2=Ian H. |date=December 1983 |title=Archean komatiites and geotherms: Solution to an apparent contradiction |journal=Geophysical Research Letters |doi=10.1029/GL010i012p01133 |bibcode=1983GeoRL..10.1133J |volume=10 |issue=12 |pages=1133–1136}}</ref>