Mark H. Thiemens

Last updated
Mark H. Thiemens
Born
St Louis, Mo, United States
EducationB.S. Univ. Miami,

M.S. Old Dominion University,

PhD. Florida State University Miami
Known forDiscovery of mass independent isotope chemistry and applications across nature in space and time, origin of life, climate change and physical chemistry of isotope effects
SpouseNasrin Marzban
ChildrenMaxwell Marzban Thiemens, Lillian Marzban Thiemens
Awards Royal Society Foreign Member

Goldschmidt Medal
E.O. Lawrence Medal
Leonard Medal
Members of National Academy Science and American Academy Arts and Science

Asteroid named in honor:

Contents

(7004) Markthiemens
Scientific career
FieldsPhysical chemistry of isotope effects,

Solar system origin and evolution,
Lunar and planetary science,
Climate change,

Origin and evolution of life
InstitutionsUniversity of California San Diego

Mark Howard Thiemens is a distinguished professor and the John Doves Isaacs Endowed Chair in Natural Philosophy of Physical Sciences in the department of chemistry and biochemistry at the University of California San Diego. [1] He is best known for the discovery of a new physical chemical phenomenon termed the mass independent isotope effect. [2]

His studies have crossed a broad range of topics including basic physical and quantum chemistry, Solar System origin, tracking the origin and evolution of life on early Earth; stratospheric chemistry, climate change and greenhouse gas identification, Mars atmospheric chemistry, past and future and isotope geochemistry. His work combines photochemical isotope studies, both laboratory and synchrotron based, field work in the South Pole, [3] Greenland Summit and the Tibetan Himalayas [4] for climate and geological sampling across China for early Earth rock records.

His non-isotope work has included discovery of an unknown source of the greenhouse gas nitrous oxide that lead the global industrial elimination of all emissions, a major contribution to changing global climate change. [5] Thiemens has worked on developing new imaging techniques for space mission return samples [6] [7] [8] [9] [10] [11] [12] and detection of superconductivity in nature. [13]

Education

Thiemens earned his bachelor of Science degree from the University of Miami. His studies with isotope geochemist Cesare Emiliani, PhD student of Harold Urey and a co-discoverer of paleoclimate temperature determination stimulated his interests in isotopes. Thiemens received a MS from Old Dominion University and PhD from Florida State University for his research using stable isotopes and particle identification using the FSU Van de Graff accelerator. He moved to the University of Chicago at the Enrico Fermi Institute for Nuclear Studies (1977-1980) where he worked with Robert N. Clayton using lunar samples to track solar wind origin and evolution, meteorite cosmochemistry, and early atmospheric chemistry.

Career

Thiemens moved to the department of chemistry at the University of California San Diego in 1980, where he was hired as an assistant professor as a replacement for Hans Seuss and took over the laboratory of Nobel Laureate Harold Urey. He was promoted to full professor in 1989, and served as the chair of the department of chemistry and biochemistry from 1996-1999. He was the founding dean of the division of physical sciences and served from 1999-2016.

Research

Thiemens research at UCSD initiated after a rebuild of the Urey isotope ratio mass spectrometer to allow measurement of both oxygen isotope ratios (18O/16O, 17O/16O). His first publication as an assistant professor reported in Science the first mass independent isotope effect which occurred during ozone formation. This was the first demonstration of a chemical process that could alter isotope ratios in a manner independently of mass difference. [14] Most strikingly was that the pattern of mass independent and the 17O/16O,18O/16O variation varied equally and reproduced the same pattern observed in primitive inclusions of the Allende carbonaceous chondritic meteorite. [15] The underlying assumption for the inclusions anomaly deriving from a nucleosynthetic component was incorrect and new models for early Solar System formation were needed and have evolved since. Much of Thiemens research has been dedicated to experimentally exploring the relevant fractionation processes that may account for the observations; including synchrotron photodissociation effects in CO. [16] [17] [18] The gas to particle formation process of the first solids in the nebula have also experimentally been shown to produce the mass independent anomaly. [19] Meteoritic material studies of Thiemens in sulfur isotopes have shown that sulfonic acids from chondritic meteorites have shown that photochemical processes have been important contributor to their molecular synthesis [20] as well other sulfur species. [21] To interpret mass independent isotope effects during photodissociation, Thiemens has worked in collaboration with Raphy Levine of Hebrew University [22] [23] to interpret mass independent isotope effects during photodissociation and better explore the fundamental chemical physics of the processes. The understanding of the basis of the ozone effect has been extensively studied by Nobel Laureate Rudy Marcus and catalyzed deeper insight into the chemical physics. [24] [25]

Thiemens has worked broadly on understanding the Earth system. Thiemens and Trogler [26] identified a source of 10% of the increasing emissions of nitrous oxide, a greenhouse gas with a radiative forcing 200 times CO2 on a per molecules basis and a 100 year plus lifetime with unidentified sources. It was shown that the manufacture of adipic acid, used in nylon production is a globally important source. In the year post publication, a global inter industry consortium banded together to eliminate all N2O emissions, with far reaching climate impact. [5]

Thiemens at South Pole marker on expedition to dig snow pit for isotope record Mark south pole.jpg
Thiemens at South Pole marker on expedition to dig snow pit for isotope record

Thiemens work in atmospheric chemistry has had extensive impact. The atmospheric chemistry of oxygen isotopes has been used to define atmospheric ozone surface reactions on Mars across billion-year time scales [27] and the oxygen isotopic carbonate record on Mars has been measured to deepen insight into reservoir mixing. [28] [29] Terrestrial atmospheric carbonate aerosol oxygen isotopic measurements allow heterogenous reaction chemistry in both atmospheres to be resolved. [30] Mass independent sulfur isotopes in Mars meteorites were used to show ultra violet SO2 photochemical reactions in the past Martian atmosphere. [31]

The Mars sulfur observations lead to one of the most important applications of the isotope effects. In the present Earth's atmosphere, the need for UV light to carry out SO2 photodissociation does not allow occurrence in today's lower atmosphere because of stratospheric ozone screening of UV light, but in a reduced oxygen atmosphere UV should pass through. Measurement of sulfur isotopes in the Earths earliest rock record revealed that large and variable mass independent sulfur isotope effects occur in 33S/32S, 36S/32S ratios, [32] as observed in Mars meteorites and laboratory experiments. [33] The short atmospheric lifetime of SO2 photochemistry is produced only with lowered O2-O3 level. For first time, oxygen levels in the earliest Earth could be determined. [34] [ circular reference ] The sulfur work is widely used to track the origin and evolution of life.

Present day sulfur isotopic anomalies in sulfate from Antarctic and Greenland ice have been used to determine the influence of massive volcanoes on the stratosphere. [35] Samples from a snow pit dug by Thiemens and colleagues have shown that there exist sources of sulfur chemistry that need to be included in studies of the atmosphere today and in the early Earth. [36]

The inclusion of radiogenic 35S with the 4 stable sulfur isotopes have further enhanced mechanistic details of the contributors to the fractionation processes in the pre Cambrium era and today. [37] An atmospheric sulfur anomaly is observed in diamonds and uniquely tracks atmosphere-mantle mixing dynamics on billion-year time scales. [38]

Thiemens has used oxygen isotopes to study oxygen chemistry of the stratosphere and mesosphere using a rocket borne cryogenic whole air sampler. [39] [40] The intersection of O(1D) from ozone photolysis exchange with CO2 and passes the isotopic anomaly to be used as a tracer. The small effect in the O2 is removed by the process of photosynthesis and respiration [41] and allows a new, highly sensitive way to quantify global primary productivity (GPP) in the world's oceans and, from oxygen trapped in ice cores across long time periods.

Using mass independent oxygen isotopes Thiemens and colleagues have applied them to further identify N2O sources. Thiemens developed the ability to measure naturally produced 35S (87-day half-life) to provide the first trans Pacific atmospheric Fukushima emissions and calculate the reactor neutronicity. [42] [43] Recently the method determined melting rates of the Tibetan Himalayan glaciers, the source of drinking water of 40% of the Earth's population. [44] Thiemens has recently shown with his colleagues the first detection of superconductivity in nature, in this case in meteorites. [13]

Service

Besides his service as Chair and Dean, Thiemens has been active in external service:

Honors

Related Research Articles

<span class="mw-page-title-main">Miller–Urey experiment</span> Experiment testing the origin of life

The Miller–Urey experiment (or Miller experiment) was an experiment in chemical synthesis carried out in 1952 that simulated the conditions thought at the time to be present in the atmosphere of the early, prebiotic Earth. It is seen as one of the first successful experiments demonstrating the synthesis of organic compounds from inorganic constituents in an origin of life scenario. The experiment used methane (CH4), ammonia (NH3), hydrogen (H2), in ratio 2:2:1, and water (H2O). Applying an electric arc (the latter simulating lightning) resulted in the production of amino acids.

<span class="mw-page-title-main">Archean</span> Geologic eon, 4031–2500 million years ago

The Archean Eon, in older sources sometimes called the Archaeozoic, is the second of the four geologic eons of Earth's history, preceded by the Hadean Eon and followed by the Proterozoic. The Archean represents the time period from 4,031 to 2,500 Mya. The Late Heavy Bombardment is hypothesized to overlap with the beginning of the Archean. The Huronian glaciation occurred at the end of the eon.

A biosignature is any substance – such as an element, isotope, molecule, or phenomenon – that provides scientific evidence of past or present life on a planet. Measurable attributes of life include its complex physical or chemical structures, its use of free energy, and the production of biomass and wastes.

Mass-independent isotope fractionation or Non-mass-dependent fractionation (NMD), refers to any chemical or physical process that acts to separate isotopes, where the amount of separation does not scale in proportion with the difference in the masses of the isotopes. Most isotopic fractionations are caused by the effects of the mass of an isotope on atomic or molecular velocities, diffusivities or bond strengths. Mass-independent fractionation processes are less common, occurring mainly in photochemical and spin-forbidden reactions. Observation of mass-independently fractionated materials can therefore be used to trace these types of reactions in nature and in laboratory experiments.

<span class="mw-page-title-main">Sulfur cycle</span> Biogeochemical cycle of sulfur

The important sulfur cycle is a biogeochemical cycle in which the sulfur moves between rocks, waterways and living systems. It is important in geology as it affects many minerals and in life because sulfur is an essential element (CHNOPS), being a constituent of many proteins and cofactors, and sulfur compounds can be used as oxidants or reductants in microbial respiration. The global sulfur cycle involves the transformations of sulfur species through different oxidation states, which play an important role in both geological and biological processes. Steps of the sulfur cycle are:

An isotopic signature is a ratio of non-radiogenic 'stable isotopes', stable radiogenic isotopes, or unstable radioactive isotopes of particular elements in an investigated material. The ratios of isotopes in a sample material are measured by isotope-ratio mass spectrometry against an isotopic reference material. This process is called isotope analysis.

<span class="mw-page-title-main">Great Oxidation Event</span> Paleoproterozoic surge in atmospheric oxygen

The Great Oxidation Event (GOE) or Great Oxygenation Event, also called the Oxygen Catastrophe, Oxygen Revolution, Oxygen Crisis or Oxygen Holocaust, was a time interval during the Earth's Paleoproterozoic era when the Earth's atmosphere and shallow seas first experienced a rise in the concentration of free oxygen. This began approximately 2.460–2.426 Ga (billion years) ago during the Siderian period and ended approximately 2.060 Ga ago during the Rhyacian. Geological, isotopic and chemical evidence suggests that biologically produced molecular oxygen (dioxygen or O2) started to accumulate in the Archean prebiotic atmosphere due to microbial photosynthesis, and eventually changed it from a weakly reducing atmosphere practically devoid of oxygen into an oxidizing one containing abundant free oxygen, with oxygen levels being as high as 10% of modern atmospheric level by the end of the GOE.

<span class="mw-page-title-main">Origin of water on Earth</span> Hypotheses for the possible sources of the water on Earth

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<span class="mw-page-title-main">Atmosphere of Mars</span> Layer of gases surrounding the planet Mars

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<span class="mw-page-title-main">Mars ocean theory</span> Astronomical theory

The Mars ocean theory states that nearly a third of the surface of Mars was covered by an ocean of liquid water early in the planet's geologic history. This primordial ocean, dubbed Paleo-Ocean or Oceanus Borealis, would have filled the basin Vastitas Borealis in the northern hemisphere, a region that lies 4–5 km below the mean planetary elevation, at a time period of approximately 4.1–3.8 billion years ago. Evidence for this ocean includes geographic features resembling ancient shorelines, and the chemical properties of the Martian soil and atmosphere. Early Mars would have required a denser atmosphere and warmer climate to allow liquid water to remain at the surface.

<span class="mw-page-title-main">Composition of Mars</span> Branch of the geology of Mars

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<span class="mw-page-title-main">Stable isotope ratio</span> Ratio of two stable isotopes

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Sulfur isotope biogeochemistry is the study of the distribution of sulfur isotopes in biological and geological materials. In addition to its common isotope, 32S, sulfur has three rare stable isotopes: 34S, 36S, and 33S. The distribution of these isotopes in the environment is controlled by many biochemical and physical processes, including biological metabolisms, mineral formation processes, and atmospheric chemistry. Measuring the abundance of sulfur stable isotopes in natural materials, like bacterial cultures, minerals, or seawater, can reveal information about these processes both in the modern environment and over Earth history.

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References

  1. ↑ "Thiemens, Mark". Chemistry and Biochemistry. 1980-01-01. Retrieved 2023-07-03.
  2. ↑ "Mark Thiemens".
  3. ↑ "In The Pits: Scientists Dig Through South Pole Snow For Climate Clues" (Press release). UC San Diego. March 1, 2013. Retrieved May 22, 2020.
  4. ↑ "Scientists Go to Great Heights to Understand Changes in Earth's Atmosphere" (Press release). UC San Diego. June 18, 2018. Retrieved May 22, 2020.
  5. 1 2 "SCIENCE WATCH; The Nylon Effect". The New York Times. 26 February 1991.
  6. ↑ "Nanoscale infrared spectroscopy as a non-destructive probe of extraterrestrial samples".
  7. ↑ Dai, S.; Fei, Z.; Ma, Q.; Rodin, A. S.; Wagner, M.; McLeod, A. S.; Liu, M. K.; Gannett, W.; Regan, W.; Watanabe, K.; Taniguchi, T.; Thiemens, M.; Dominguez, G.; Neto, A. H. Castro; Zettl, A.; Keilmann, F.; Jarillo-Herrero, P.; Fogler, M. M.; Basov, D. N. (7 March 2014). "Tunable Phonon Polaritons in Atomically Thin van der Waals Crystals of Boron Nitride". Science. 343 (6175): 1125–1129. Bibcode:2014Sci...343.1125D. doi:10.1126/science.1246833. hdl: 1721.1/90317 . PMID   24604197. S2CID   4253950.
  8. ↑ Fei, Z.; Rodin, A. S.; Andreev, G. O.; Bao, W.; McLeod, A. S.; Wagner, M.; Zhang, L. M.; Zhao, Z.; Thiemens, M.; Dominguez, G.; Fogler, M. M.; Neto, A. H. Castro; Lau, C. N.; Keilmann, F.; Basov, D. N. (July 2012). "Gate-tuning of graphene plasmons revealed by infrared nano-imaging". Nature. 487 (7405): 82–85. arXiv: 1202.4993 . Bibcode:2012Natur.487...82F. doi:10.1038/nature11253. PMID   22722866. S2CID   4348703.
  9. ↑ Dominguez, Gerardo; Mcleod, A. S.; Gainsforth, Zack; Kelly, P.; Bechtel, Hans A.; Keilmann, Fritz; Westphal, Andrew; Thiemens, Mark; Basov, D. N. (9 December 2014). "Nanoscale infrared spectroscopy as a non-destructive probe of extraterrestrial samples". Nature Communications. 5 (1): 5445. Bibcode:2014NatCo...5.5445D. doi: 10.1038/ncomms6445 . PMID   25487365.
  10. ↑ Dai, S.; Ma, Q.; Andersen, T.; Mcleod, A. S.; Fei, Z.; Liu, M. K.; Wagner, M.; Watanabe, K.; Taniguchi, T.; Thiemens, M.; Keilmann, F.; Jarillo-Herrero, P.; Fogler, M. M.; Basov, D. N. (22 April 2015). "Subdiffractional focusing and guiding of polaritonic rays in a natural hyperbolic material". Nature Communications. 6 (1): 6963. arXiv: 1502.04094 . Bibcode:2015NatCo...6.6963D. doi:10.1038/ncomms7963. PMC   4421822 . PMID   25902364.
  11. ↑ Fei, Z.; Rodin, A. S.; Gannett, W.; Dai, S.; Regan, W.; Wagner, M.; Liu, M. K.; McLeod, A. S.; Dominguez, G.; Thiemens, M.; Castro Neto, Antonio H.; Keilmann, F.; Zettl, A.; Hillenbrand, R.; Fogler, M. M.; Basov, D. N. (November 2013). "Electronic and plasmonic phenomena at graphene grain boundaries". Nature Nanotechnology. 8 (11): 821–825. arXiv: 1311.6827 . Bibcode:2013NatNa...8..821F. doi:10.1038/nnano.2013.197. PMID   24122082. S2CID   494891.
  12. ↑ Dai, S.; Ma, Q.; Liu, M. K.; Andersen, T.; Fei, Z.; Goldflam, M. D.; Wagner, M.; Watanabe, K.; Taniguchi, T.; Thiemens, M.; Keilmann, F.; Janssen, G. C. a. M.; Zhu, S.-E.; Jarillo-Herrero, P.; Fogler, M. M.; Basov, D. N. (August 2015). "Graphene on hexagonal boron nitride as a tunable hyperbolic metamaterial". Nature Nanotechnology. 10 (8): 682–686. arXiv: 1501.06956 . Bibcode:2015NatNa..10..682D. doi:10.1038/nnano.2015.131. PMID   26098228. S2CID   205452562.
  13. 1 2 Wampler, James; Thiemens, Mark; Cheng, Shaobo; Zhu, Yimei; Schuller, Ivan K. (7 April 2020). "Superconductivity found in meteorites". Proceedings of the National Academy of Sciences. 117 (14): 7645–7649. Bibcode:2020PNAS..117.7645W. doi: 10.1073/pnas.1918056117 . PMC   7148572 . PMID   32205433.
  14. ↑ Thiemens, M. H.; Heidenreich, J. E. (4 March 1983). "The Mass-Independent Fractionation of Oxygen: A Novel Isotope Effect and Its Possible Cosmochemical Implications". Science. 219 (4588): 1073–1075. Bibcode:1983Sci...219.1073T. doi:10.1126/science.219.4588.1073. PMID   17811750. S2CID   26466899.
  15. ↑ Clayton, R. N.; Grossman, L.; Mayeda, T. K. (2 November 1973). "A Component of Primitive Nuclear Composition in Carbonaceous Meteorites". Science. 182 (4111): 485–488. Bibcode:1973Sci...182..485C. doi:10.1126/science.182.4111.485. PMID   17832468. S2CID   22386977.
  16. ↑ "New Clues to Oxygen at the Origin of the Solar System".
  17. ↑ Chakraborty, S.; Ahmed, M.; Jackson, T. L.; Thiemens, M. H. (5 September 2008). "Experimental Test of Self-Shielding in Vacuum Ultraviolet Photodissociation of CO". Science. 321 (5894): 1328–1331. Bibcode:2008Sci...321.1328C. doi:10.1126/science.1159178. PMID   18772432. S2CID   713105.
  18. ↑ Chakraborty, Subrata; Davis, Ryan D.; Ahmed, Musahid; Jackson, Teresa L.; Thiemens, Mark H. (14 July 2012). "Oxygen isotope fractionation in the vacuum ultraviolet photodissociation of carbon monoxide: Wavelength, pressure, and temperature dependency". The Journal of Chemical Physics. 137 (2): 024309. Bibcode:2012JChPh.137b4309C. doi:10.1063/1.4730911. PMID   22803538. S2CID   7312120.
  19. ↑ "Scientists solve mystery of odd patterns of oxygen in solar system's earliest rocks".
  20. ↑ Cooper, George W.; Thiemens, Mark H.; Jackson, Teresa L.; Chang, Sherwood (22 August 1997). "Sulfur and Hydrogen Isotope Anomalies in Meteorite Sulfonic Acids". Science. 277 (5329): 1072–1074. Bibcode:1997Sci...277.1072C. doi:10.1126/science.277.5329.1072. hdl: 2060/19980038124 . PMID   9262469.
  21. ↑ Rai, V. K. (12 August 2005). "Photochemical Mass-Independent Sulfur Isotopes in Achondritic Meteorites". Science. 309 (5737): 1062–1065. Bibcode:2005Sci...309.1062R. doi:10.1126/science.1112954. PMID   16099982. S2CID   26306652.
  22. ↑ Muskatel, B. H.; Remacle, F.; Thiemens, M. H.; Levine, R. D. (24 March 2011). "On the strong and selective isotope effect in the UV excitation of N2 with implications toward the nebula and Martian atmosphere". Proceedings of the National Academy of Sciences. 108 (15): 6020–6025. Bibcode:2011PNAS..108.6020M. doi: 10.1073/pnas.1102767108 . PMC   3076819 . PMID   21441106.
  23. ↑ Chakraborty, S.; Muskatel, B. H.; Jackson, T. L.; Ahmed, M.; Levine, R. D.; Thiemens, M. H. (29 September 2014). "Massive isotopic effect in vacuum UV photodissociation of N2 and implications for meteorite data". Proceedings of the National Academy of Sciences. 111 (41): 14704–14709. Bibcode:2014PNAS..11114704C. doi: 10.1073/pnas.1410440111 . PMC   4205658 . PMID   25267643.
  24. ↑ Gao, Y. Q. (31 May 2001). "Strange and Unconventional Isotope Effects in Ozone Formation". Science. 293 (5528): 259–263. Bibcode:2001Sci...293..259G. doi:10.1126/science.1058528. PMID   11387441. S2CID   867229.
  25. ↑ "Rudolph A. (Rudy) Marcus | Division of Chemistry and Chemical Engineering".
  26. ↑ Thiemens, M. H.; Trogler, W. C. (22 February 1991). "Nylon Production: An Unknown Source of Atmospheric Nitrous Oxide". Science. 251 (4996): 932–934. Bibcode:1991Sci...251..932T. doi:10.1126/science.251.4996.932. PMID   17847387. S2CID   22090514.
  27. ↑ Farquhar, J. (5 June 1998). "Atmosphere-Surface Interactions on Mars: 17O Measurements of Carbonate from ALH 84001". Science. 280 (5369): 1580–1582. doi:10.1126/science.280.5369.1580. PMID   9616116.
  28. ↑ "New chemical analysis of ancient Martian meteorite provides clues to planet's history of habitability".
  29. ↑ Shaheen, Robina; Niles, Paul B.; Chong, Kenneth; Corrigan, Catherine M.; Thiemens, Mark H. (13 January 2015). "Carbonate formation events in ALH 84001 trace the evolution of the Martian atmosphere". Proceedings of the National Academy of Sciences. 112 (2): 336–341. Bibcode:2015PNAS..112..336S. doi: 10.1073/pnas.1315615112 . PMC   4299197 . PMID   25535348.
  30. ↑ Shaheen, R.; Abramian, A.; Horn, J.; Dominguez, G.; Sullivan, R.; Thiemens, M. H. (8 November 2010). "Detection of oxygen isotopic anomaly in terrestrial atmospheric carbonates and its implications to Mars". Proceedings of the National Academy of Sciences. 107 (47): 20213–20218. Bibcode:2010PNAS..10720213S. doi: 10.1073/pnas.1014399107 . PMC   2996665 . PMID   21059939.
  31. ↑ Farquhar, James; Savarino, Joel; Jackson, Terri L.; Thiemens, Mark H. (March 2000). "Evidence of atmospheric sulphur in the martian regolith from sulphur isotopes in meteorites". Nature. 404 (6773): 50–52. Bibcode:2000Natur.404...50F. doi:10.1038/35003517. PMID   10716436. S2CID   731902.
  32. ↑ Farquhar, J. (4 August 2000). "Atmospheric Influence of Earth's Earliest Sulfur Cycle". Science. 289 (5480): 756–758. Bibcode:2000Sci...289..756F. doi:10.1126/science.289.5480.756. PMID   10926533.
  33. ↑ Farquhar, James; Savarino, Joel; Airieau, Sabine; Thiemens, Mark H. (25 December 2001). "Observation of wavelength-sensitive mass-independent sulfur isotope effects during SO photolysis: Implications for the early atmosphere". Journal of Geophysical Research: Planets. 106 (E12): 32829–32839. Bibcode:2001JGR...10632829F. doi: 10.1029/2000JE001437 .
  34. ↑ Great Oxidation Event
  35. ↑ Baroni, M.; Thiemens, M. H.; Delmas, R. J.; Savarino, J. (5 January 2007). "Mass-Independent Sulfur Isotopic Compositions in Stratospheric Volcanic Eruptions". Science. 315 (5808): 84–87. Bibcode:2007Sci...315...84B. doi:10.1126/science.1131754. PMID   17204647. S2CID   40342760.
  36. ↑ Shaheen, R.; Abaunza, M. M.; Jackson, T. L.; McCabe, J.; Savarino, J.; Thiemens, M. H. (4 August 2014). "Large sulfur-isotope anomaly in nonvolcanic sulfate aerosol and its implications for the Archean atmosphere". Proceedings of the National Academy of Sciences. 111 (33): 11979–11983. Bibcode:2014PNAS..11111979S. doi: 10.1073/pnas.1406315111 . PMC   4143030 . PMID   25092338.
  37. ↑ Lin, Mang; Zhang, Xiaolin; Li, Menghan; Xu, Yilun; Zhang, Zhisheng; Tao, Jun; Su, Binbin; Liu, Lanzhong; Shen, Yanan; Thiemens, Mark H. (21 August 2018). "Five-S-isotope evidence of two distinct mass-independent sulfur isotope effects and implications for the modern and Archean atmospheres". Proceedings of the National Academy of Sciences. 115 (34): 8541–8546. Bibcode:2018PNAS..115.8541L. doi: 10.1073/pnas.1803420115 . PMC   6112696 . PMID   30082380.
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