Editing Free-air gravity anomaly (section)

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[[File:Chicxulub Free-Air Gravity anomaly.png|Circular free-air gravity anomaly over the [[Chicxulub Crater]]|thumb]]
In [[geophysics]], the '''free-air gravity anomaly''', often simply called the '''free-air anomaly''', is the measured [[gravity anomaly]] after a '''free-air correction''' is applied to account for the [[elevation]] at which a measurement is made. It does so by adjusting these measurements of gravity to what would have been measured at a reference level, which is commonly taken as [[mean sea level]] or the [[geoid]].<ref name=Fowler>{{cite book|first=C.M.R.|last=Fowler|author-link=Mary Fowler (geologist)|title=The Solid Earth: An Introduction to Global Geophysics|year=2005|edition=2|publisher=[[Cambridge University Press]]|location=[[Cambridge, UK]]|isbn=978-0-521-89307-7|pages=205–206}}</ref><ref>{{cite journal |title=Introduction to Potential Fields: Gravity |journal=U.S. Geological Survey Fact Sheets |date=1997 |volume=FS–239–95 |bibcode=1997usgs.rept...19W |url=https://pubs.usgs.gov/fs/fs-0239-95/fs-0239-95.pdf |access-date=30 May 2019 |last1=Water Resources Division |first1=U. S. Geological Survey |series=Fact Sheet |page=19 |doi=10.3133/fs23995 }}</ref>