John W. Valley

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John Williams Valley (born February 28, 1948 in Winchester, Massachusetts) is an American geochemist and petrologist. He is an expert on stable isotope geochemistry, [1] especially as applied to understanding the evolution of the Earth's crust. [2] [3] [4] [5]

Contents

Biography

Valley grew up in Lexington, Massachusetts [2] and started collecting rocks when he was four years old. [6] He studied geology at Dartmouth College (AB 1970) and at the University of Michigan (MS 1977, PhD 1980) [7] [8] He was an assistant professor at Rice University (1980-1983) before moving to the University of Wisconsin, Madison, where he was an assistant professor (1983-1985), associate professor (1985-1989), and full professor from 1989 [5] until his retirement in 2019 as professor emeritus. [6] In 2005 he was appointed Charles R. Van Hise Distinguished Professor. He was a Fulbright Scholar at the University of Edinburgh (1989-1990). His doctoral students include Claudia Mora, Jean Morrison, and John Eiler. [9] [5]

Valley is an expert on stable isotope geochemistry applied to metamorphic, igneous and sedimentary rocks. He has worked extensively on high-grade metamorphic Precambrian rocks, especially in the Grenville Province of New York and Canada. [1] He and his colleagues investigated the Sierra Nevada batholith, [10] [11] lavas from Pacific islands, [12] [13] [14] and rhyolites from the Yellowstone Plateau Volcanic Field. [15]

Valley has studied numerous proxies for paleoclimate including speleothems, [16] mollusks, [17] foraminifera, [18] otoliths, [19] pearls, [20] and fossil teeth. [21] He organized three conferences on applications of new SIMS technology to paleoclimatology (HiRes2013, 2015 and 2017). [22]

The Apex Chert is a flint-like rock from Western Australia, which contains some of the oldest known fossils. The microscopic fossils are single-celled bacteria, 3,500 million years old, and contain no nucleus (prokaryotes). They are either spherical or in filament-like chains. Chert typically consists of the petrified remains of siliceous ooze. Apex Chert.jpg
The Apex Chert is a flint-like rock from Western Australia, which contains some of the oldest known fossils. The microscopic fossils are single-celled bacteria, 3,500 million years old, and contain no nucleus (prokaryotes). They are either spherical or in filament-like chains. Chert typically consists of the petrified remains of siliceous ooze.

Valley and others demonstrated that carbonates in the Martian meteorite ALH84001 formed at low temperatures, [23] and that material from the comet 81P/Wild is chondrule-like indicating transport from the asteroid belt to the cold outer reaches of the solar system. [24]

In 2001, Valley, with 3 co-workers, discovered the oldest known samples of Earth, detrital zircons from the Jack Hills in Western Australia, which document the existence of differentiated crust on Earth by 4.4 Ga (billion years ago) about 150 Myr (million years) after the Earth's formation at 4.55 Ga. [25] The oxygen isotope ratios of these zircons indicate that the Earth cooled sooner, by over 600 Myr, than previous evidence indicated and that oceans were habitable to life by 4.3 Ga, 800 Myr earlier than the oldest well-documented micro-fossils. He has also shown, by a unique correlation of carbon isotope ratios (measured at micron-scale) to morphology, that these ancient fossils are indeed biogenic and lived in complex communities of microbial life 3,465 million years ago, indicating that the first life came earlier. [26]

Valley has been active in professional service. In 2005, he founded the Wisconsin Secondary Ion Mass Spectrometry Laboratory (WiscSIMS) [27] to develop new methods for measuring stable isotopes in the nano to micrometer range. [2] Over 400 scientists have now worked at WiscSIMS. He served on many committees for mineralogy, geochemistry, and geology, including the NRC Committee on the Scientific Context for the Exploration of the Moon (2007). [5] [28] From 2014 to 2023 he served on the board of governors for the Gemological Institute of America. He has been associate editor for the Geological Society of America Bulletin (1985-1991), the American Journal of Science (1996-) and the Proceedings of the National Academy of Sciences (2021-). From 2011 to 2015 he was an editor in chief for the journal Elements. [5] He was the president of Mineralogical Society of America in 2005–2006.


Valley was elected a Fellow of the Geological Society of America (GSA, 1992), the Mineralogical Society of America (MSA, 1993), [5] the American Geophysical Union (AGU, 1996), the European Association of Geochemistry (2011), and the Geochemical Society (2011). AGU gave him the Norman L. Bowen Award in 2003 [29] In 2019 GSA awarded him the Arthur L. Day Medal. In 2022 he received the Roebling Medal from MSA. [30] He was elected a Member of the National Academy of Sciences in 2019. [5]

In 2017, the International Mineralogical Association (IMA) approved the name "valleyite" for the mineral Ca4Fe6O13, discovered by Huifang Xu and named in honor of John W. Valley. [5] [31] [32]

In 1972 Valley married Andrée Simone Taylor. [33] They have two sons, Matthew and David. [1] Valley is also a skilled woodworker. Before graduate school, he made furniture in Helena, Montana while there with Andrée, who was Resident Artist at the Archie Bray Foundation for the Ceramic Arts. [30] Andrée works extensively in metal and ceramic sculpture. [34] Her work is displayed internationally.

Selected publications

as editor

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References

  1. 1 2 3 Gates, Alexander E. (2009). "Valley, John W.". A to Z of Earth Scientists. Infobase. pp. 272–274. ISBN   9781438109190.
  2. 1 2 3 "John W. Valley". Member Directory, National Academy of Sciences.
  3. ↑ Wilde, Simon A.; Valley, John W.; Peck, William H.; Graham, Colin M. (2001). "Evidence from detrital zircons for the existence of continental crust and oceans on the Earth 4.4 Gyr ago". Nature. 409 (6817): 175–178. doi:10.1038/35051550. PMID   11196637. S2CID   4319774.
  4. ↑ "John W. Valley, Charles R. Van Hise Professor, Emeritus". Department of Geoscience, University of Wisconsin-Madison. 19 January 2022.
  5. 1 2 3 4 5 6 7 8 "John W. Valley, Curriculum Vitae" (PDF). University of Wisconsin-Madison.
  6. 1 2 Conklin, Aaron R. (October 24, 2019). "Geoscience's John Valley honored for distinction in the field". University of Wisconsin-Madison.
  7. ↑ Valley, John W. (1977). Calc-silicate reactions in Grenville marble, Adirondack MTS., New York / (M.S. Thesis). hdl:2027.42/115588.
  8. ↑ Valley, John Williams (1980). The Role of Fluids During Metamorphism of Marbles and Associated Rocks in the Adirondack Mountains, New York (Ph.D. Thesis). hdl:2027.42/158015.
  9. ↑ https://www.nasonline.org/member-directory/members/20038936.html
  10. ↑ Lackey, J.; Valley, J.; Saleeby, J. (2005). "Supracrustal input to magmas in the deep crust of Sierra Nevada batholith: Evidence from high-O zircon". Earth and Planetary Science Letters. 235 (1–2): 315–330. doi:10.1016/j.epsl.2005.04.003.
  11. ↑ Lackey, Jade Star; Valley, John W.; Chen, James H.; Stockli, Daniel F. (2008). "Dynamic Magma Systems, Crustal Recycling, and Alteration in the Central Sierra Nevada Batholith: The Oxygen Isotope Record". Journal of Petrology. 49 (7): 1397–1426. doi: 10.1093/petrology/egn030 .
  12. ↑ Eiler, John M.; Valley, John W.; Stolper, Edward M. (1996). "Oxygen isotope ratios in olivine from the Hawaii Scientific Drilling Project". Journal of Geophysical Research: Solid Earth. 101 (B5): 11807–11813. Bibcode:1996JGR...10111807E. doi:10.1029/95JB03194. S2CID   46215107.
  13. ↑ Eiler, John M.; Farley, Kenneth A.; Valley, John W.; Stolper, Edward M.; Hauri, Eric H.; Craig, Harmon (1995). "Oxygen isotope evidence against bulk recycled sediment in the mantle sources of Pitcairn Island lavas". Nature. 377 (6545): 138–141. Bibcode:1995Natur.377..138E. doi:10.1038/377138a0. S2CID   4360176.
  14. ↑ Eiler, J. M. (2000). "Oxygen Isotope Geochemistry of Oceanic-Arc Lavas". Journal of Petrology. 41 (2): 229–256. doi: 10.1093/petrology/41.2.229 .
  15. ↑ Bindeman, Ilya N.; Valley, John W. (2001). "Low-δ18O Rhyolites from Yellowstone: Magmatic Evolution Based on Analyses of Zircons and Individual Phenocrysts". Journal of Petrology. 42 (8): 1491–1517. doi: 10.1093/petrology/42.8.1491 .
  16. ↑ Orland IJ, Bar-Matthews M, Kita NT, Ayalon A, Matthews A, Valley JW (2009) Climate deterioration in the eastern Mediterranean from 200 BC to 1100 AD as revealed by ion microprobe analysis of speleothems from Soreq Cave, Israel. Quat. Res., 71: 27-35.
  17. ↑ Linzmeier BJ, Kozdon R, Peters SE, Valley JW (2016) Oxygen isotope variability within growth bands suggests daily depth migration behavior is recorded in Nautilus shell aragonite, PLOS One, p 1-31. DOI:10.1371/journal.pone.0153890
  18. ↑ Kozdon R; Ushikubo T; Kita NT; Spicuzza M; Valley JW (2009) Intratest oxygen isotope variability in planktonic foraminifera: New insights from in situ measurements by ion microprobe. doi:10.1016/j.chemgeo.2008.10.032, Chem. Geol., 258, 327-337.
  19. ↑ Helser T, Kastelle C, McKay J, Orland IJ, Kozdon R, Valley JW (2018) Evaluation of micromilling/conventional isotope ratio mass spectrometry and secondary ion mass spectrometry of δ18O in fish otoliths for sclerochronology. Rapid Comm. in Mass Spectrometry. 32: 1781-1790. DOI: 10.1002/rcm.8231
  20. ↑ Farfan GA, Zhou C, Valley JW, Orland IJ (2021) Coupling Mineralogy and Oxygen Isotopes to Seasonal Environmental Shifts Recorded in Modern Freshwater Pearl Nacre from Kentucky Lake. Geochem Geophys Geosyst, 22, 12, 17p, doi.org/10.1029/2021GC009995.
  21. ↑ Kohn, M. J., Schoeninger, M. J., and Valley, J. W., (1996) Herbivore tooth oxygen isotope compositions: Effects of diet and physiology. Geochim. Cosmochim. Acta, 60, 3889-3896.
  22. ↑ http://www.geology.wisc.edu/~wiscsims/HiRes2017/pdfs/talks/HiRes2017_D1_0900_Valley.pdf
  23. ↑ Valley, John W.; Eiler, John M.; Graham, Colin M.; Gibson, Everett K.; Romanek, Christopher S.; Stolper, Edward M. (1997). "Low-Temperature Carbonate Concretions in the Martian Meteorite ALH84001: Evidence from Stable Isotopes and Mineralogy". Science. 275 (5306): 1633–1638. Bibcode:1997Sci...275.1633V. doi:10.1126/science.275.5306.1633. PMID   9054355. S2CID   29483663.
  24. ↑ Nakamura, Tomoki; Noguchi, Takaaki; Tsuchiyama, Akira; Ushikubo, Takayuki; Kita, Noriko T.; Valley, John W.; Zolensky, Michael E.; Kakazu, Yuki; Sakamoto, Kanako; Mashio, Etsuko; Uesugi, Kentaro; Nakano, Tsukasa (2008). "Chondrulelike Objects in Short-Period Comet 81P/Wild 2". Science. 321 (5896): 1664–1667. Bibcode:2008Sci...321.1664N. doi:10.1126/science.1160995. PMID   18801994. S2CID   206514269.
  25. ↑ Wilde, Simon A.; Valley, John W.; Peck, William H.; Graham, Colin M. (2001). "Evidence from detrital zircons for the existence of continental crust and oceans on the Earth 4.4 Gyr ago". Nature. 409 (6817): 175–178. doi:10.1038/35051550. PMID   11196637. S2CID   4319774.
  26. ↑ Schopf JW, Kitajima K, Spicuzza M, Kudryavtsev A, Valley JW (2018) SIMS Analyses of the Oldest Known Assemblage of Microfossils Document Their Taxon-Correlated Carbon Isotope Compositions. Proc. Natl. Acad. Sci. 115: 53-58. doi: 10.1073/pnas.1718063115
  27. ↑ "Wisconsin Secondary Ion Mass Spectrometry Laboratory". University of Wisconsin-Madison.
  28. ↑ "The Scientific Context for the Exploration of the Moon". National Academies Press. 2007.
  29. ↑ "Norman L. Bowen Award". American Geophysical Union (AGU).
  30. 1 2 Star Lackey, Jade; Peck, William H. (2023). "Presentation of the 2022 Roebling Medal from MSA". American Mineralogist. p. 781.
  31. ↑ "Valleyite". mindat.org.
  32. ↑ "Huifang Xu". University of Wisconsin-Madison.
  33. ↑ https://www.andreevalley.com/
  34. ↑ https://www.andreevalley.com/
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