Editing Prospecting (section)

=== Electromagnetic prospecting ===
{{see also| Turam method}}
The introduction of modern gravity and magnetic surveying methods has greatly facilitated the prospecting process. Airborne gravimeters and magnetometers can collect data from vast areas and highlight anomalous geologic features.<ref>{{Cite book|last=Dobrin|first=Milton B.|title=Introduction to Geophysical Prospecting|year=1960|publisher=New York, McGraw-Hill |url=https://archive.org/details/introductiontoge00dobr|url-access=registration}}</ref> Three-dimensional inversions of audio-magnetotellurics (AMT) is used to find conductive materials up to a few kilometers into the Earth, which has been helpful to locate kimberlite pipes, as well as tungsten and copper.<ref>{{Cite journal|last1=Farquharson|first1=Colin|last2=Craven|first2=James|date=August 2009|title=Three-dimensional inversion of magnetotelluric data for mineral exploration: An example from the McArthur River uranium deposit, Saskatchewan, Canada|journal=Journal of Applied Geophysics|volume=68|issue=4|pages=450–458|doi=10.1016/j.jappgeo.2008.02.002|bibcode=2009JAG....68..450F}}</ref><ref>{{Cite journal|last=Shi|first=Yuan|date=January 2020|title=Three-dimensional audio-frequency magnetotelluric imaging of Zhuxi copper-tungsten polymetallic deposits, South China|journal=Journal of Applied Geophysics|volume=172|pages=103910|doi=10.1016/j.jappgeo.2019.103910|bibcode=2020JAG...17203910S|doi-access=}}</ref>

Another relatively new prospecting technique is using low frequency electromagnetic (EM) waves for 'sounding' into the Earth's crust. These low frequency waves will respond differently based on the material they pass through, allowing for analysts to create three-dimensional images of potential ore bodies or volcanic intrusions. This technique is used for a variety of prospecting, but can mainly be for finding conductive materials.<ref>{{cite journal|last1=Singh|first1=Anand|last2=Sharma|first2=S.P.|date=2015|title=Fast imaging of subsurface conductors using very low-frequency electromagnetic data|journal=Geophysical Prospecting|volume=63|issue=6|page=1355 |doi=10.1111/1365-2478.12323 |bibcode=2015GeopP..63.1355S |s2cid=131284478 }}</ref> So far these low frequency EM techniques have been proven for geothermal exploration as well as for coal bed methane analysis.<ref>{{cite journal|last1=Wang|first1=Nan|date=2017|title=Passive super-low frequency electromagnetic prospecting technique|journal=Frontiers of Earth Science|volume=11|issue=2 |pages=248–267|doi=10.1007/s11707-017-0597-4 |bibcode=2017FrES...11..248W |s2cid=113545890 }}</ref><ref>{{cite journal|last1=Van Der Kruk|first1=J|date=2002|title=An apparent-resistivity concept for low-frequency electromagnetic sounding techniques|journal=Geophysical Prospecting|volume=48|issue=6}}</ref>