Editing Noble gas (section)

==== Sampling of noble gases ====
Noble gas measurements can be obtained from sources like [[volcanic vents]], [[Hot spring|springs]], and [[geothermal wells]] following specific sampling protocols.<ref>{{Cite journal |last1=Hilton |first1=D. R. |last2=Fischer |first2=T. P. |last3=Marty |first3=B. |date=2002-01-01 |title=Noble Gases and Volatile Recycling at Subduction Zones |url=https://pubs.geoscienceworld.org/rimg/article/47/1/319-370/235395 |journal=Reviews in Mineralogy and Geochemistry |language=en |volume=47 |issue=1 |pages=319–370 |doi=10.2138/rmg.2002.47.9 |bibcode=2002RvMG...47..319H |issn=1529-6466}}</ref> The classic specific sampling protocol include the following.
* Copper tubes - These are standard refrigeration copper tubes, cut to ~10&nbsp;cm³ with a 3/8” outer diameter, and are used for sampling volatile discharges by connecting an inverted funnel to the tube via TygonⓇ tubing, ensuring one-way inflow and preventing air contamination. Their malleability allows for cold welding or pinching off to seal the ends after sufficient flushing with the sample.
** [[File:Giggenbach_Bottle.jpg|thumb|Sampling of noble gases using a Giggenbach bottle, a funnel is placed on top of the hot spring to focus the stream of sample towards the bottle via the Tygon tube. A geochemist is controlling the flow of the sample inlet using a Teflon valve. Note the condensation process inside the evacuated Giggenbach bottle.]]Giggenbach bottles - Giggenbach bottles are evacuated glass flasks with a Teflon stopcock, used for sampling and storing gases. They require pre-evacuation before sampling, as noble gases accumulate in the headspace.<ref>{{Cite web |title=Methods for the collection and analysis of geothermal and volcanic water and gas samples |url=https://search.worldcat.org/title/316795976 |access-date=2024-10-19 |website=search.worldcat.org |language=en}}</ref> These bottles were first invented and distributed by a Werner F. Giggenbach, a German chemist.<ref>{{Cite journal |last=Giggenbach |first=W. F. |date=1975-03-01 |title=A simple method for the collection and analysis of volcanic gas samples |url=https://link.springer.com/article/10.1007/BF02596953 |journal=Bulletin Volcanologique |language=en |volume=39 |issue=1 |pages=132–145 |doi=10.1007/BF02596953 |bibcode=1975BVol...39..132G |issn=1432-0819}}</ref>

===== Analysis of noble gases =====
Noble gases have numerous isotopes and subtle mass variation that requires high-precision detection systems.  Originally, scientists used [[magnetic sector mass spectrometry]], which is time-consuming and has low sensitivity due to "peak jumping mode".<ref>{{Cite journal |url=https://pubs.aip.org/rsi/article/27/11/928/299004/High-Sensitivity-Mass-Spectrometer-for-Noble-Gas |access-date=2024-10-16 |journal=Review of Scientific Instruments |doi=10.1063/1.1715415 |title=High Sensitivity Mass Spectrometer for Noble Gas Analysis |date=1956 |last1=Reynolds |first1=John H. |volume=27 |issue=11 |pages=928–934 |bibcode=1956RScI...27..928R }}</ref><ref name="Mark-2009">{{Cite journal |last1=Mark |first1=D. F. |last2=Barfod |first2=D. |last3=Stuart |first3=F. M. |last4=Imlach |first4=J. |date=October 2009 |title=The ARGUS multicollector noble gas mass spectrometer: Performance for 40 Ar/ 39 Ar geochronology |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2009GC002643 |journal=Geochemistry, Geophysics, Geosystems |language=en |volume=10 |issue=10 |doi=10.1029/2009GC002643 |issn=1525-2027}}</ref> Multiple-collector mass spectrometers, like [[Quadrupole mass analyzer|Quadrupole mass spectrometers]] (QMS), enable simultaneous detection of isotopes, improving sensitivity and throughput.<ref name="Mark-2009" /> Before analysis, sample preparation is essential due to the low abundance of noble gases, involving extraction, purification system.<ref name="Burnard-2013"/> Extraction allows liberation of noble gases from their carrier (major phase; fluid or solid) while purification remove impurities and improve concentration per unit sample volume.<ref name="Mtili-2021">{{Cite journal |last1=Mtili |first1=K. M. |last2=Byrne |first2=D. J. |last3=Tyne |first3=R. L. |last4=Kazimoto |first4=E. O. |last5=Kimani |first5=C. N. |last6=Kasanzu |first6=C. H. |last7=Hillegonds |first7=D. J. |last8=Ballentine |first8=C. J. |last9=Barry |first9=P. H. |date=2021-12-20 |title=The origin of high helium concentrations in the gas fields of southwestern Tanzania |url=https://linkinghub.elsevier.com/retrieve/pii/S000925412100485X |journal=Chemical Geology |volume=585 |pages=120542 |doi=10.1016/j.chemgeo.2021.120542 |bibcode=2021ChGeo.58520542M |issn=0009-2541}}</ref> Cryogenic traps are used for sequential analysis without peak interference by stepwise temperature raise.<ref name="Li-2021">{{Cite journal |last1=Li |first1=Yan |last2=Tootell |first2=Damian |last3=Holland |first3=Greg |last4=Zhou |first4=Zheng |date=November 2021 |title=Performance of the NGX High-Resolution Multiple Collector Noble Gas Mass Spectrometer |journal=Geochemistry, Geophysics, Geosystems |language=en |volume=22 |issue=11 |doi=10.1029/2021GC009997 |bibcode=2021GGG....2209997L |issn=1525-2027|doi-access=free }}</ref>

Research labs have successfully developed miniaturized field-based mass spectrometers, such as the portable mass spectrometer ([https://gasometrix.com/products/ miniRuedi]), which can analyze noble gases with an analytical uncertainty of 1-3% using low-cost vacuum systems and quadrupole mass analyzers.<ref>{{Cite journal |last1=Brennwald |first1=Matthias S. |last2=Schmidt |first2=Mark |last3=Oser |first3=Julian |last4=Kipfer |first4=Rolf |date=2016-12-20 |title=A Portable and Autonomous Mass Spectrometric System for On-Site Environmental Gas Analysis |url=https://pubs.acs.org/doi/10.1021/acs.est.6b03669 |journal=Environmental Science & Technology |language=en |volume=50 |issue=24 |pages=13455–13463 |doi=10.1021/acs.est.6b03669 |pmid=27993051 |bibcode=2016EnST...5013455B |issn=0013-936X}}</ref> [[File:Gchron.copernicus.org.jpg|thumb|Extraction and purification (clean up) mass spectrometer line.]]