Geochronology

@techreport{allen1942the13,
    author = "Allen, B. F",
    title = "The geologic age of the Mississippi River",
    year = "1942",
    howpublished = "Bulletin of the",
    note = "talkorigins\_source = {true}; raw\_reference = {Allen, B. F., 1942, The geologic age of the Mississippi River: Bulletin of the}"
}

@misc{hurley1959how76,
    author = "Hurley, P. M",
    title = "How Old Is the Earth?",
    year = "1959",
    howpublished = "New York, Anchor\Doubleday",
    note = "talkorigins\_source = {true}; raw\_reference = {Hurley, P. M., 1959, How Old Is the Earth?: New York, Anchor\Doubleday.}"
}

@misc{a1964the69,
    author = "A, M.",
    title = "The Geochronological Scale of the Upper Proterozoic (Riphean",
    year = "1964",
    note = "talkorigins\_source = {true}; raw\_reference = {M. A., 1964, The Geochronological Scale of the Upper Proterozoic (Riphean}"
}

@misc{garris1964the6,
    author = "Garris, M. A. and Gerling, E. K. and et al",
    title = "The absolute geochronological",
    year = "1964",
    note = "talkorigins\_source = {true}; raw\_reference = {Garris, M. A., Gerling, E. K., et al., 1964, The absolute geochronological}"
}

@misc{whitcomb1964origin122,
    author = "Whitcomb, J. C",
    title = "Origin of the Solar System",
    year = "1964",
    howpublished = "Presbyterian and Reformed",
    note = "talkorigins\_source = {true}; raw\_reference = {Whitcomb, J. C., 1964, Origin of the Solar System: Presbyterian and Reformed}"
}

@misc{damon1965correlation56,
    author = "Damon, P. E",
    title = "Correlation and chronology of ore deposits and volcanic",
    year = "1965",
    note = "talkorigins\_source = {true}; raw\_reference = {Damon, P. E., 1965, Correlation and chronology of ore deposits and volcanic}"
}

@misc{broecker1966absolute27,
    author = "Broecker, W. S",
    title = "Absolute dating and the astronomical theory of",
    year = "1966",
    note = "talkorigins\_source = {true}; raw\_reference = {Broecker, W. S., 1966, Absolute dating and the astronomical theory of}"
}

@misc{faul1966ages65,
    author = "Faul, H",
    title = "Ages of Rocks, Planets, and Stars",
    year = "1966",
    howpublished = "New York, McGraw-Hill",
    note = "talkorigins\_source = {true}; raw\_reference = {Faul, H., 1966, Ages of Rocks, Planets, and Stars: New York, McGraw-Hill.}"
}

@misc{runcorn1966corals95,
    author = "Runcorn, S. K",
    title = "Corals as paleontological clocks",
    year = "1966",
    howpublished = "Scientific American, v",
    note = "talkorigins\_source = {true}; raw\_reference = {Runcorn, S. K., 1966, Corals as paleontological clocks: Scientific American, v.}"
}

@misc{cook1968do44,
    author = "Cook, M. A",
    title = "Do radiological clocks need repair?",
    year = "1968",
    howpublished = "Creation Research",
    note = "talkorigins\_source = {true}; raw\_reference = {Cook, M. A., 1968, Do radiological clocks need repair?: Creation Research}"
}

@misc{eicher1968geologic62,
    author = "Eicher, D. L",
    title = "Geologic Time",
    year = "1968",
    howpublished = "Englewood Cliffs, Prentice-Hall",
    note = "talkorigins\_source = {true}; raw\_reference = {Eicher, D. L., 1968, Geologic Time: Englewood Cliffs, Prentice-Hall.}"
}

@phdthesis{mesolella1968milankovich30,
    author = "Mesolella, K. J",
    title = "Milankovich hypothesis supported by precise dating",
    year = "1968",
    note = "talkorigins\_source = {true}; raw\_reference = {Mesolella, K. J., 1968, Milankovich hypothesis supported by precise dating}"
}

@misc{noble1968deepocean88,
    author = "Noble, C. S. and Naughton, J. J",
    title = "Deep-ocean basalts",
    year = "1968",
    howpublished = "Inert gas and",
    note = "talkorigins\_source = {true}; raw\_reference = {Noble, C. S., and Naughton, J. J., 1968, Deep-ocean basalts: Inert gas and}"
}

@misc{pannella1968paleontological90,
    author = "Pannella, G. and MacClintock, C. and Thompson, M. N",
    title = "Paleontological",
    year = "1968",
    note = "talkorigins\_source = {true}; raw\_reference = {Pannella, G., MacClintock, C., and Thompson, M. N., 1968, Paleontological}"
}

@misc{tedford1970principles114,
    author = "Tedford, R. H",
    title = "Principles and practices of mammalian geochronology in",
    year = "1970",
    note = "talkorigins\_source = {true}; raw\_reference = {Tedford, R. H., 1970, Principles and practices of mammalian geochronology in}"
}

@misc{bucha1971in40,
    author = "Bucha, V",
    title = "in Michael, H",
    year = "1971",
    howpublished = "N., and Ralph, E. K., eds., Dating",
    note = "talkorigins\_source = {true}; raw\_reference = {Bucha, V., 1971,, in Michael, H. N., and Ralph, E. K., eds., Dating}"
}

@misc{allen1972the15,
    author = "Allen, B. F",
    title = "The geologic age of the Mississippi River",
    year = "1972",
    howpublished = "Creation Research Society",
    note = "talkorigins\_source = {true}; raw\_reference = {Allen, B. F., 1972, The geologic age of the Mississippi River: Creation Research Society}"
}

@misc{york1972the126,
    author = "York, D. and Farquar, R. M",
    title = "The Earth's Age and Geochronology",
    year = "1972",
    howpublished = "Oxford",
    note = "talkorigins\_source = {true}; raw\_reference = {York, D., and Farquar, R. M., 1972, The Earth's Age and Geochronology: Oxford,}"
}

@misc{slusher1973critique107,
    author = "Slusher, H",
    title = "Critique of Radiometric Dating",
    year = "1973",
    howpublished = "San Diego, California",
    note = "talkorigins\_source = {true}; raw\_reference = {Slusher, H., 1973, Critique of Radiometric Dating: San Diego, California,}"
}

@misc{schramm1974the101,
    author = "Schramm, D. N",
    title = "The Age of the Elements",
    year = "1974",
    howpublished = "Scientific American, v. 230, no",
    note = "talkorigins\_source = {true}; raw\_reference = {Schramm, D. N., 1974, The Age of the Elements: Scientific American, v. 230, no.}"
}

@article{weber1974geochronology,
    author = "Weber, Jon N.",
    title = "Geochronology: Radiometric dating of rocks and minerals",
    year = "1974",
    journal = "Earth-Science Reviews",
    url = "https://doi.org/10.1016/0012-8252(74)90117-2",
    doi = "10.1016/0012-8252(74)90117-2",
    number = "4",
    openalex = "W1967515298",
    pages = "349",
    volume = "10"
}

@misc{richards1975lead93,
    author = "Richards, J. R",
    title = "Lead isotope data on three north Austrailian galena",
    year = "1975",
    note = "talkorigins\_source = {true}; raw\_reference = {Richards, J. R., 1975, Lead isotope data on three north Austrailian galena}"
}

@misc{eicher1976geologic63,
    author = "Eicher, D. L",
    title = "Geologic Time [2nd ed.]",
    year = "1976",
    howpublished = "Englewood Cliffs, New Jersey, Prentice-Hall",
    note = "talkorigins\_source = {true}; raw\_reference = {Eicher, D. L., 1976, Geologic Time [2nd ed.]: Englewood Cliffs, New Jersey, Prentice-Hall,}"
}

@book{slusher1976age109,
    author = "Slusher, H",
    title = "Age of the Cosmos",
    year = "1976",
    publisher = "San Diego, California, Creation-Life Publishers",
    note = "talkorigins\_source = {true}; raw\_reference = {Slusher, H., 1976, Age of the Cosmos: San Diego, California, Creation-Life Publishers.}"
}

@misc{grootes1978carbon1472,
    author = "Grootes, P. M",
    title = "Carbon-14 time scale extended",
    year = "1978",
    howpublished = "comparison of chronologies",
    note = "talkorigins\_source = {true}; raw\_reference = {Grootes, P. M., 1978, Carbon-14 time scale extended: comparison of chronologies:}"
}

@misc{vg1978precambrian11,
    author = "V. G., Mirkhodzhayev and I. M., et al",
    title = "Precambrian in Central Asia [in",
    year = "1978",
    note = "talkorigins\_source = {true}; raw\_reference = {V. G., Mirkhodzhayev, I. M., et al., 1978, Precambrian in Central Asia [in}"
}

@misc{woodmorappe1979radiometric124,
    author = "Woodmorappe, J",
    title = "Radiometric geochronology reappraised",
    year = "1979",
    howpublished = "Creation Research",
    note = "talkorigins\_source = {true}; raw\_reference = {Woodmorappe, J., 1979, Radiometric geochronology reappraised: Creation Research}"
}

@misc{slusher1981critique110,
    author = "Slusher, H. S",
    title = "Critique of Radiometric Dating [2nd ed.]",
    year = "1981",
    howpublished = "San Diego",
    note = "talkorigins\_source = {true}; raw\_reference = {Slusher, H. S., 1981, Critique of Radiometric Dating [2nd ed.]: San Diego,}"
}

@misc{stanley1981the112,
    author = "Stanley, S. M",
    title = "The New Evolutionary Time Table",
    year = "1981",
    howpublished = "Fossils, Genes, and the",
    note = "talkorigins\_source = {true}; raw\_reference = {Stanley, S. M., 1981, The New Evolutionary Time Table: Fossils, Genes, and the}"
}

@misc{barnes1982young25,
    author = "Barnes, T. G",
    title = "Young age for the moon and earth",
    year = "1982",
    howpublished = "ICR Impact Series, v",
    note = "talkorigins\_source = {true}; raw\_reference = {Barnes, T. G., 1982, Young age for the moon and earth: ICR Impact Series, v.}"
}

@misc{brush1982finding35,
    author = "Brush, S. G",
    title = "Finding the Age of the Earth",
    year = "1982",
    howpublished = "By Physics or by Faith?",
    note = "talkorigins\_source = {true}; raw\_reference = {Brush, S. G., 1982, Finding the Age of the Earth: By Physics or by Faith?:}"
}

@misc{hitch1982dendrochronology74,
    author = "Hitch, C. J",
    title = "Dendrochronology and serendipity",
    year = "1982",
    howpublished = "American Scientist, v. 70",
    note = "talkorigins\_source = {true}; raw\_reference = {Hitch, C. J., 1982, Dendrochronology and serendipity: American Scientist, v. 70,}"
}

@misc{matthews1982radiometric82,
    author = "Matthews, R. W",
    title = "Radiometric dating and the age of the earth",
    year = "1982",
    howpublished = "Ex Nihilo",
    note = "talkorigins\_source = {true}; raw\_reference = {Matthews, R. W., 1982, Radiometric dating and the age of the earth: Ex Nihilo,}"
}

@misc{rybka1982consequences97,
    author = "Rybka, T. W",
    title = "Consequences of time dependent nuclear decay indices on half",
    year = "1982",
    note = "talkorigins\_source = {true}; raw\_reference = {Rybka, T. W., 1982, Consequences of time dependent nuclear decay indices on half}"
}

@misc{weber1982answers119,
    author = "Weber, C. G",
    title = "Answers to creationist attacks on Carbon-14 dating",
    year = "1982",
    note = "talkorigins\_source = {true}; raw\_reference = {Weber, C. G., 1982, Answers to creationist attacks on Carbon-14 dating:}"
}

@misc{young1982christianity128,
    author = "Young, D. A",
    title = "Christianity and the Age of the Earth",
    year = "1982",
    howpublished = "Grand Rapids",
    note = "talkorigins\_source = {true}; raw\_reference = {Young, D. A., 1982, Christianity and the Age of the Earth: Grand Rapids,}"
}

@misc{abell1983the1,
    author = "Abell, G. O",
    title = "The Ages of the Earth and the Universe, in Godfrey, L",
    year = "1983",
    note = "talkorigins\_source = {true}; raw\_reference = {Abell, G. O., 1983, The Ages of the Earth and the Universe, in Godfrey, L.}"
}

@misc{awbery1983space19,
    author = "Awbery, F. T",
    title = "Space dust, the moon's surface, and the age of the cosmos",
    year = "1983",
    note = "talkorigins\_source = {true}; raw\_reference = {Awbery, F. T., 1983, Space dust, the moon's surface, and the age of the cosmos:}"
}

@misc{awbrey1983space21,
    author = "Awbrey, F. T",
    title = "Space Dust, the Moon's Surface, and the Age of the Cosmos",
    year = "1983",
    note = "talkorigins\_source = {true}; raw\_reference = {Awbrey, F. T., 1983, Space Dust, the Moon's Surface, and the Age of the Cosmos:}"
}

@misc{brush1983ghosts37,
    author = "Brush, S. G",
    title = "Ghosts from the Nineteenth Century",
    year = "1983",
    howpublished = "Creationist Arguments for a Young",
    note = "talkorigins\_source = {true}; raw\_reference = {Brush, S. G., 1983, Ghosts from the Nineteenth Century: Creationist Arguments for a Young}"
}

@misc{dalrymple1983can46,
    author = "Dalrymple, G. B",
    title = "Can the earth be dated from the decay of its magnetic",
    year = "1983",
    note = "talkorigins\_source = {true}; raw\_reference = {Dalrymple, G. B., 1983, Can the earth be dated from the decay of its magnetic}"
}

@misc{dorn1983cationratio60,
    author = "Dorn, R. I",
    title = "Cation-ratio dating",
    year = "1983",
    howpublished = "a new rock varnish age-determination",
    note = "talkorigins\_source = {true}; raw\_reference = {Dorn, R. I., 1983, Cation-ratio dating: a new rock varnish age-determination}"
}

@misc{jacobs1983reversals77,
    author = "Jacobs, J. A",
    title = "Reversals of the Earth's Magnetic Field",
    year = "1983",
    howpublished = "Bristol, Adam",
    note = "talkorigins\_source = {true}; raw\_reference = {Jacobs, J. A., 1983, Reversals of the Earth's Magnetic Field: Bristol, Adam}"
}

@misc{morris1983science86,
    author = "Morris, H. M",
    title = "Science, Scripture and the Young Earth",
    year = "1983",
    howpublished = "San Diego",
    note = "talkorigins\_source = {true}; raw\_reference = {Morris, H. M., 1983, Science, Scripture and the Young Earth: San Diego,}"
}

@misc{dalrymple1984how48,
    author = "Dalrymple, G. B",
    title = "How Old is the Earth? A Reply to 'Scientific' Creationism, in",
    year = "1984",
    note = "talkorigins\_source = {true}; raw\_reference = {Dalrymple, G. B., 1984, How Old is the Earth? A Reply to 'Scientific' Creationism, in}"
}

The total number of radiometric age determinations that have been made on geologically significant samples now exceeds about 300,000. This total, which includes many duplicate determinations by different investigators using different techniques, is being augmented at the rate of about 15,000 per year. Nevertheless, estimates of the ages of geological eras have not changed significantly since the first few dozen determinations were made more than 50 years ago. Consequently, the level of confidence that can be assigned to the specific ages on the radiometric time scale is much greater than is generally realized.

@article{doi101017s2475262200004421,
    author = "Osmond, J.K.",
    title = "The Consistency of Radiometric Dating in the Geologic Record",
    year = "1984",
    journal = "The Paleontological Society Special Publications",
    abstract = "The total number of radiometric age determinations that have been made on geologically significant samples now exceeds about 300,000. This total, which includes many duplicate determinations by different investigators using different techniques, is being augmented at the rate of about 15,000 per year. Nevertheless, estimates of the ages of geological eras have not changed significantly since the first few dozen determinations were made more than 50 years ago. Consequently, the level of confidence that can be assigned to the specific ages on the radiometric time scale is much greater than is generally realized.",
    url = "https://doi.org/10.1017/s2475262200004421",
    doi = "10.1017/s2475262200004421",
    openalex = "W2809904035",
    references = "weber1974geochronology"
}

@misc{francisco1984american50,
    author = "Francisco, San",
    title = "American Association for the Advancement of Science",
    year = "1984",
    note = "talkorigins\_source = {true}; raw\_reference = {San Francisco, 1984, American Association for the Advancement of Science,}"
}

@misc{vanandel1985new117,
    author = "Van Andel, T. H",
    title = "New Views on an Old Planet",
    year = "1985",
    howpublished = "Continental Drift and the",
    note = "talkorigins\_source = {true}; raw\_reference = {Van Andel, T. H., 1985, New Views on an Old Planet: Continental Drift and the}"
}

@misc{ackerman1986its3,
    author = "Ackerman, P. D",
    title = "It's a Young World After All",
    year = "1986",
    howpublished = "Grand Rapids, Michigan",
    note = "talkorigins\_source = {true}; raw\_reference = {Ackerman, P. D., 1986, It's a Young World After All: Grand Rapids, Michigan,}"
}

@misc{skehan1986the103,
    author = "Skehan, J. W",
    title = "The Age of the Earth, of Life, and of Mankind",
    year = "1986",
    howpublished = "Geology and",
    note = "talkorigins\_source = {true}; raw\_reference = {Skehan, J. W., 1986, The Age of the Earth, of Life, and of Mankind: Geology and}"
}

@misc{amato1987tics17,
    author = "Amato, I",
    title = "Tics in the tocs of molecular clocks",
    year = "1987",
    howpublished = "Science News, v. 131, p",
    note = "talkorigins\_source = {true}; raw\_reference = {Amato, I., 1987, Tics in the tocs of molecular clocks: Science News, v. 131, p.}"
}

@misc{fisher1987the66,
    author = "Fisher, D. E",
    title = "The Birth of the Earth",
    year = "1987",
    howpublished = "A Wanderlied Through Space, Time",
    note = "talkorigins\_source = {true}; raw\_reference = {Fisher, D. E., 1987, The Birth of the Earth: A Wanderlied Through Space, Time}"
}

@misc{weisburd1987sea121,
    author = "Weisburd, S",
    title = "Sea cycle clock",
    year = "1987",
    howpublished = "Science News, v. 131, p. 154-155",
    note = "talkorigins\_source = {true}; raw\_reference = {Weisburd, S., 1987, Sea cycle clock: Science News, v. 131, p. 154-155.}"
}

@misc{cloud1988oasis42,
    author = "Cloud, P",
    title = "Oasis in Space",
    year = "1988",
    howpublished = "Earth History from the Beginning: New York",
    note = "talkorigins\_source = {true}; raw\_reference = {Cloud, P., 1988, Oasis in Space: Earth History from the Beginning: New York,}"
}

@misc{schidlowski1988a99,
    author = "Schidlowski, M",
    title = "A 3,800-million-year isotopic record of life from carbon",
    year = "1988",
    note = "talkorigins\_source = {true}; raw\_reference = {Schidlowski, M., 1988, A 3,800-million-year isotopic record of life from carbon}"
}

@misc{badash1989theageoftheearth23,
    author = "Badash, L",
    title = "The-age-of-the-earth debate",
    year = "1989",
    howpublished = "Scientific American, v. 261, no",
    note = "talkorigins\_source = {true}; raw\_reference = {Badash, L., 1989, The-age-of-the-earth debate: Scientific American, v. 261, no.}"
}

@misc{monastersky1989new84,
    author = "Monastersky, R",
    title = "New Record for World's Oldest Rocks",
    year = "1989",
    howpublished = "Science News, v",
    note = "talkorigins\_source = {true}; raw\_reference = {Monastersky, R., 1989, New Record for World's Oldest Rocks: Science News, v.}"
}

@misc{kerr1990marking79,
    author = "Kerr, R. A",
    title = "Marking the Ice Ages in coral instead of mud",
    year = "1990",
    howpublished = "Science, v",
    note = "talkorigins\_source = {true}; raw\_reference = {Kerr, R. A., 1990, Marking the Ice Ages in coral instead of mud: Science, v.}"
}

@misc{kerr1990the81,
    author = "Kerr, R. A",
    title = "The Ice Age bones of contention",
    year = "1990",
    howpublished = "Science, v. 248, p. 32",
    note = "talkorigins\_source = {true}; raw\_reference = {Kerr, R. A., 1990, The Ice Age bones of contention: Science, v. 248, p. 32.}"
}

@misc{wendorf1990dating33,
    author = "Wendorf, J",
    title = "Dating Pleistocene archeological sites by protein",
    year = "1990",
    note = "talkorigins\_source = {true}; raw\_reference = {Wendorf, J., 1990, Dating Pleistocene archeological sites by protein}"
}

Single zircons from two Early Cambrian volcanic horizons have been analysed using the SHRIMP ion microprobe. Full details of the analytical procedures and data reduction are given. Zircons from tuff within the Lie de Vin Formation, near Tiout, Morocco, show little spread in U-Pb age and have a mean value of 521 ± 7 Ma (2σ). Those from a bentonite within unit 5 of the Meishucun section near Kunming, southern China, show relatively dispersed U-Pb ages, revealing the presence of both detrital or xenocrystic grains as well as areas within grains that have lost radiogenic Pb. The main population has a mean age of 525 ± 7 Ma, but a mean 207 Pb/ 206 Pb age of 539 ± 34 Ma which is a maximum estimate for the bentonite age. These results conflict with previous Rb-Sr whole rock ages of c. 580 Ma for overlying Cambrian shales at Meishucun, and c. 570 Ma for Atdabanian shales from the E. Yangtse Gorges area.

@article{doi101144gsjgs14920171,
    author = "Compston, W. and Williams, Ian S. and Kirschvink, Joseph L. and Zhang, Zichao and Guogan, Ma",
    title = "Zircon U-Pb ages for the Early Cambrian time-scale",
    year = "1992",
    journal = "Journal of the Geological Society",
    abstract = "Single zircons from two Early Cambrian volcanic horizons have been analysed using the SHRIMP ion microprobe. Full details of the analytical procedures and data reduction are given. Zircons from tuff within the Lie de Vin Formation, near Tiout, Morocco, show little spread in U-Pb age and have a mean value of 521 ± 7 Ma (2σ). Those from a bentonite within unit 5 of the Meishucun section near Kunming, southern China, show relatively dispersed U-Pb ages, revealing the presence of both detrital or xenocrystic grains as well as areas within grains that have lost radiogenic Pb. The main population has a mean age of 525 ± 7 Ma, but a mean 207 Pb/ 206 Pb age of 539 ± 34 Ma which is a maximum estimate for the bentonite age. These results conflict with previous Rb-Sr whole rock ages of c. 580 Ma for overlying Cambrian shales at Meishucun, and c. 570 Ma for Atdabanian shales from the E. Yangtse Gorges area.",
    url = "https://doi.org/10.1144/gsjgs.149.2.0171",
    doi = "10.1144/gsjgs.149.2.0171",
    openalex = "W2080522683",
    references = "doi1010160012821x84900177, doi101017s0094837300006539, doi101038320258a0, doi101139e83050, doi1018814epiiugs1985v8i2003, doi105860choice304422"
}

Abstract Geochronology, Time Scales, and Global Stratigraphic Correlation - The last decade has witnessed significant advances in analytic techniques and methodologic approaches to understanding earth history. This publication is a well-constructed geochronologic framework that allows estimation of rates of geologic processes, correlation of stratigraphies, and placement of discrete events in temporal order. Resulting from a research symposium at the 67th Annual SEPM meeting in New Orleans, Louisiana, April 1993, the 16 papers of this volume represent a broad spectrum of approaches to understanding earth history and the passage of geologic time.

@book{doi102110pec9504,
    author = "Berggren, William A. and Kent, Dennis V. and Aubry, Marie‐Pierre and Hardenbol, Jan",
    title = "Geochronology, Time Scales and Global Stratigraphic Correlation",
    year = "1995",
    booktitle = "SEPM (Society for Sedimentary Geology) eBooks",
    abstract = "Abstract Geochronology, Time Scales, and Global Stratigraphic Correlation - The last decade has witnessed significant advances in analytic techniques and methodologic approaches to understanding earth history. This publication is a well-constructed geochronologic framework that allows estimation of rates of geologic processes, correlation of stratigraphies, and placement of discrete events in temporal order. Resulting from a research symposium at the 67th Annual SEPM meeting in New Orleans, Louisiana, April 1993, the 16 papers of this volume represent a broad spectrum of approaches to understanding earth history and the passage of geologic time.",
    url = "https://doi.org/10.2110/pec.95.04",
    doi = "10.2110/pec.95.04",
    openalex = "W1799003920"
}

Using replicate measurements of a homogeneous reference zircon, the discrimination of Pb+ and UO+ ions relative to U+ observed in zircon analysis with the SHRIMP ion microprobe has been established as a power law relationship. This relationship minimizes uncertainty in comparative measurement of 206Pb/238U ages in zircons. Ages thus obtained have been compared with isotope dilution thermal ionisation mass spectrometric (1DTIMS) analysis of zircons in the Paterson Volcanics (Carboniferous, Australia) and 40Ar/39Ar dating of sanidines in the Z1 tonstein (Carboniferous, Germany). No bias can be detected between the three dating...

@incollection{doi102110pec95040003,
    author = "Claoué-Long, Jonathan C. and Compston, W. and Roberts, J. C. and Fanning, C. Mark",
    title = "Two Carboniferous Ages A Comparison of Shrimp Zircon Dating with Conventional Zircon Ages and 40 Ar/ 39 Ar Analysis",
    year = "1995",
    booktitle = "SEPM (Society for Sedimentary Geology) eBooks",
    abstract = "Using replicate measurements of a homogeneous reference zircon, the discrimination of Pb+ and UO+ ions relative to U+ observed in zircon analysis with the SHRIMP ion microprobe has been established as a power law relationship. This relationship minimizes uncertainty in comparative measurement of 206Pb/238U ages in zircons. Ages thus obtained have been compared with isotope dilution thermal ionisation mass spectrometric (1DTIMS) analysis of zircons in the Paterson Volcanics (Carboniferous, Australia) and 40Ar/39Ar dating of sanidines in the Z1 tonstein (Carboniferous, Germany). No bias can be detected between the three dating...",
    url = "https://doi.org/10.2110/pec.95.04.0003",
    doi = "10.2110/pec.95.04.0003",
    openalex = "W2196999081"
}

@article{crossref2000the,
    title = "The ecology of invasions by animals and plants",
    year = "2000",
    journal = "Choice Reviews Online",
    url = "https://doi.org/10.5860/choice.38-1547",
    doi = "10.5860/choice.38-1547",
    number = "03",
    openalex = "W4301885210",
    pages = "38-1547-38-1547",
    volume = "38"
}

Rhenium-osmium (Re-Os) data from migrated hydrocarbons establish the timing of petroleum emplacement for the giant oil sand deposits of Alberta, Canada, at 112 +/- 5.3 million years ago. This date does not support models that invoke oil generation and migration for these deposits in the Late Cretaceous. Most Re-Os data from a variety of deposits within the giant hydrocarbon system show similar characteristics, supporting the notion of a single source for these hydrocarbons. The Re-Os data disqualify Cretaceous rocks as the primary hydrocarbon source but suggest an origin from older source rocks. This approach should be applicable to dating oil deposits worldwide.

@article{doi101126science1111081,
    author = "Selby, David and Creaser, Robert A.",
    title = "Direct Radiometric Dating of Hydrocarbon Deposits Using Rhenium-Osmium Isotopes",
    year = "2005",
    journal = "Science",
    abstract = "Rhenium-osmium (Re-Os) data from migrated hydrocarbons establish the timing of petroleum emplacement for the giant oil sand deposits of Alberta, Canada, at 112 +/- 5.3 million years ago. This date does not support models that invoke oil generation and migration for these deposits in the Late Cretaceous. Most Re-Os data from a variety of deposits within the giant hydrocarbon system show similar characteristics, supporting the notion of a single source for these hydrocarbons. The Re-Os data disqualify Cretaceous rocks as the primary hydrocarbon source but suggest an origin from older source rocks. This approach should be applicable to dating oil deposits worldwide.",
    url = "https://doi.org/10.1126/science.1111081",
    doi = "10.1126/science.1111081",
    openalex = "W2136348758",
    references = "doi101016s0009254103001992"
}

@article{rasmussen2005radiometric,
    author = "Rasmussen, Birger",
    title = "Radiometric dating of sedimentary rocks: the application of diagenetic xenotime geochronology",
    year = "2005",
    journal = "Earth-Science Reviews",
    url = "https://doi.org/10.1016/j.earscirev.2004.05.004",
    doi = "10.1016/j.earscirev.2004.05.004",
    number = "3-4",
    openalex = "W2000089948",
    pages = "197-243",
    volume = "68",
    references = "doi1010160016703774901495, doi1010160016703787903619, doi1010160031920186900932, doi101016b9780444408266500078, doi10103835051550, doi101107s0567739476001551, doi101126science22847071529, doi1015159780691220239, doi1021130530469, doi102475ajs2588583, openalexw1487925322, openalexw1624806571"
}

@incollection{crossref2009radiometric,
    title = "Radiometric Dating",
    year = "2009",
    booktitle = "Environmental Sciences: A Student's Companion",
    url = "https://doi.org/10.4135/9781446216187.n169",
    doi = "10.4135/9781446216187.n169",
    openalex = "W4256566598",
    pages = "332-332"
}

@misc{crossref2012radiometric,
    title = "Radiometric Dating",
    year = "2012",
    url = "https://doi.org/10.5772/1948",
    doi = "10.5772/1948",
    openalex = "W4240340781"
}

Xenotime occurs as epitaxial overgrowths on detrital zircons in the Mesoproterozoic Revett Formation (Belt Supergroup) at the Spar Lake red bed-associated Cu-Ag deposit, western Montana. The deposit formed during diagenesis of Revett strata, where oxidizing metal-bearing hydrothermal fluids encountered a reducing zone. Samples for geochronology were collected from several mineral zones. Xenotime overgrowths (1-30 μm wide) were found in polished thin sections from five ore and near-ore zones (chalcocite-chlorite, bornitecalcite, galena-calcite, chalcopyrite-ankerite, and pyrite-calcite), but not in more distant zones across the region. Thirty-two in situ SHRIMP U-Pb analyses on xenotime overgrowths yield a weighted average of 207Pb/ 206Pb ages of 1409 ± 8 Ma, interpreted as the time of mineralization. This age is about 40 to 60 m.y. after deposition of the Revett Formation. Six other xenotime overgrowths formed during a younger event at 1304 ± 19 Ma. Several isolated grains of xenotime have 207Pb/ 206Pb ages in the range of 1.67 to 1.51 Ga, and thus are considered detrital in origin. Trace element data can distinguish Spar Lake xenotimes of different origins. Based on in situ SHRIMP analysis, detrital xenotime has heavy rare earth elements-enriched patterns similar to those of igneous xenotime, whereas xenotime overgrowths of inferred hydrothermal origin have hump-shaped (i.e., middle rare earth elements-enriched) patterns. The two ages of hydrothermal xenotime can be distinguished by slightly different rare earth elements patterns. In addition, 1409 Ma xenotime overgrowths have higher Eu and Gd contents than the 1304 Ma overgrowths. Most xenotime overgrowths from the Spar Lake deposit have elevated As concentrations, further suggesting a genetic relationship between the xenotime formation and Cu-Ag mineralization.

@article{doi102113econgeo10761251,
    author = "Aleinikoff, J. N. and Hayes, Timothy S. and Evans, Karl V. and Mazdab, F. K. and Pillers, R. M. and Fanning, C. Mark",
    title = "SHRIMP U-Pb Ages of Xenotime and Monazite from the Spar Lake Red Bed-Associated Cu-Ag Deposit, Western Montana: Implications for Ore Genesis",
    year = "2012",
    journal = "Economic Geology",
    abstract = "Xenotime occurs as epitaxial overgrowths on detrital zircons in the Mesoproterozoic Revett Formation (Belt Supergroup) at the Spar Lake red bed-associated Cu-Ag deposit, western Montana. The deposit formed during diagenesis of Revett strata, where oxidizing metal-bearing hydrothermal fluids encountered a reducing zone. Samples for geochronology were collected from several mineral zones. Xenotime overgrowths (1-30 μm wide) were found in polished thin sections from five ore and near-ore zones (chalcocite-chlorite, bornitecalcite, galena-calcite, chalcopyrite-ankerite, and pyrite-calcite), but not in more distant zones across the region. Thirty-two in situ SHRIMP U-Pb analyses on xenotime overgrowths yield a weighted average of 207Pb/ 206Pb ages of 1409 ± 8 Ma, interpreted as the time of mineralization. This age is about 40 to 60 m.y. after deposition of the Revett Formation. Six other xenotime overgrowths formed during a younger event at 1304 ± 19 Ma. Several isolated grains of xenotime have 207Pb/ 206Pb ages in the range of 1.67 to 1.51 Ga, and thus are considered detrital in origin. Trace element data can distinguish Spar Lake xenotimes of different origins. Based on in situ SHRIMP analysis, detrital xenotime has heavy rare earth elements-enriched patterns similar to those of igneous xenotime, whereas xenotime overgrowths of inferred hydrothermal origin have hump-shaped (i.e., middle rare earth elements-enriched) patterns. The two ages of hydrothermal xenotime can be distinguished by slightly different rare earth elements patterns. In addition, 1409 Ma xenotime overgrowths have higher Eu and Gd contents than the 1304 Ma overgrowths. Most xenotime overgrowths from the Spar Lake deposit have elevated As concentrations, further suggesting a genetic relationship between the xenotime formation and Cu-Ag mineralization.",
    url = "https://doi.org/10.2113/econgeo.107.6.1251",
    doi = "10.2113/econgeo.107.6.1251",
    openalex = "W2122859732",
    references = "doi102113econgeo10761143"
}

Significance The causal mechanisms of global glaciations are poorly understood. The transition to a Neoproterozoic Snowball Earth after more than 1 Gy without glaciation represents the most dramatic episode of climate change in the geological record. Here we present new Re-Os geochronology, which, together with existing U-Pb ages, reveal that the glacial period in northwest Canada lasted ∼55 My. Additionally, we present an original method to track tectonic influences on these climatic perturbations with a high-resolution coupled Os-Sr isotope curve across the transition from an ice-free world to a Neoproterozoic Snowball Earth. The data indicate that increases in mantle-derived, juvenile material emplaced onto continents and subsequently weathered into the oceans led to enhanced consumption and sequestration of CO 2 into sediments.

@article{doi101073pnas1317266110,
    author = "Rooney, Alan D. and Macdonald, Francis A. and Strauss, Justin V. and Dudás, Francis Ö. and Hallmann, Christian and Selby, David",
    title = "Re-Os geochronology and coupled Os-Sr isotope constraints on the Sturtian snowball Earth",
    year = "2013",
    journal = "Proceedings of the National Academy of Sciences",
    abstract = "Significance The causal mechanisms of global glaciations are poorly understood. The transition to a Neoproterozoic Snowball Earth after more than 1 Gy without glaciation represents the most dramatic episode of climate change in the geological record. Here we present new Re-Os geochronology, which, together with existing U-Pb ages, reveal that the glacial period in northwest Canada lasted ∼55 My. Additionally, we present an original method to track tectonic influences on these climatic perturbations with a high-resolution coupled Os-Sr isotope curve across the transition from an ice-free world to a Neoproterozoic Snowball Earth. The data indicate that increases in mantle-derived, juvenile material emplaced onto continents and subsequently weathered into the oceans led to enhanced consumption and sequestration of CO 2 into sediments.",
    url = "https://doi.org/10.1073/pnas.1317266110",
    doi = "10.1073/pnas.1317266110",
    openalex = "W2059510927",
    references = "doi101016s0009254103001992"
}

The Belt–Purcell Supergroup, northern Idaho, western Montana, and southern British Columbia, is a thick succession of Mesoproterozoic sedimentary rocks with an age range of about 1470–1400 Ma. Stratigraphic layers within several sedimentary units were sampled to apply the new technique of U–Pb dating of xenotime that sometimes forms as rims on detrital zircon during burial diagenesis; xenotime also can form epitaxial overgrowths on zircon during hydrothermal and metamorphic events. Belt Supergroup units sampled are the Prichard and Revett Formations in the lower Belt, and the McNamara and Garnet Range Formations and Pilcher Quartzite in the upper Belt. Additionally, all samples that yielded xenotime were also processed for detrital zircon to provide maximum age constraints for the time of deposition and information about provenances; the sample of Prichard Formation yielded monazite that was also analyzed. Ten xenotime overgrowths from the Prichard Formation yielded a U–Pb age of 1458 ± 4 Ma. However, because scanning electron microscope – backscattered electrons (SEM–BSE) imagery suggests complications due to possible analysis of multiple age zones, we prefer a slightly older age of 1462 ± 6 Ma derived from the three oldest samples, within error of a previous U–Pb zircon age on the syn-sedimentary Plains sill. We interpret the Prichard xenotime as diagenetic in origin. Monazite from the Prichard Formation, originally thought to be detrital, yielded Cretaceous metamorphic ages. Xenotime from the McNamara and Garnet Range Formations and Pilcher Quartzite formed at about 1160–1050 Ma, several hundred million years after deposition, and probably also experienced Early Cretaceous growth. These xenotime overgrowths are interpreted as metamorphic–diagenetic in origin (i.e., derived during greenschist facies metamorphism elsewhere in the basin, but deposited in sub-greenschist facies rocks). Several xenotime grains are older detrital grains of igneous derivation. A previous study on the Revett Formation at the Spar Lake Ag–Cu deposit provides data for xenotime overgrowths in several ore zones formed by hydrothermal processes; herein, those results are compared with data from newly analyzed diagenetic, metamorphic, and magmatic xenotime overgrowths. The origin of a xenotime overgrowth is reflected in its rare-earth element (REE) pattern. Detrital (i.e., igneous) xenotime has a large negative Eu anomaly and is heavy rare-earth element (HREE)-enriched (similar to REE in igneous zircon). Diagenetic xenotime has a small negative Eu anomaly and flat HREE (Tb to Lu). Hydrothermal xenotime is depleted in light rare-earth element (LREE), has a small negative Eu anomaly, and decreasing HREE. Metamorphic xenotime is very LREE-depleted, has a very small negative Eu anomaly, and is strongly depleted in HREE (from Gd to Lu). Because these characteristics seem to be process related, they may be useful for interpretation of xenotime of unknown origin. The occurrence of 1.16–1.05 Ga metamorphic xenotime, in the apparent absence of pervasive deformation structures, suggests that the heating may be related to poorly understood regional heating due to broad regional underplating of mafic magma. These results may be additional evidence (together with published ages from metamorphic titanite, zircon, monazite, and garnet) for an enigmatic, Grenville-age metamorphic event that is more widely recognized in the southwestern and eastern United States.

@article{doi101139cjes20140239,
    author = "Aleinikoff, John N. and Lund, Karen and Fanning, C. Mark",
    title = "SHRIMP U–Pb and REE data pertaining to the origins of xenotime in Belt Supergroup rocks: evidence for ages of deposition, hydrothermal alteration, and metamorphism",
    year = "2015",
    journal = "Canadian Journal of Earth Sciences",
    abstract = "The Belt–Purcell Supergroup, northern Idaho, western Montana, and southern British Columbia, is a thick succession of Mesoproterozoic sedimentary rocks with an age range of about 1470–1400 Ma. Stratigraphic layers within several sedimentary units were sampled to apply the new technique of U–Pb dating of xenotime that sometimes forms as rims on detrital zircon during burial diagenesis; xenotime also can form epitaxial overgrowths on zircon during hydrothermal and metamorphic events. Belt Supergroup units sampled are the Prichard and Revett Formations in the lower Belt, and the McNamara and Garnet Range Formations and Pilcher Quartzite in the upper Belt. Additionally, all samples that yielded xenotime were also processed for detrital zircon to provide maximum age constraints for the time of deposition and information about provenances; the sample of Prichard Formation yielded monazite that was also analyzed. Ten xenotime overgrowths from the Prichard Formation yielded a U–Pb age of 1458 ± 4 Ma. However, because scanning electron microscope – backscattered electrons (SEM–BSE) imagery suggests complications due to possible analysis of multiple age zones, we prefer a slightly older age of 1462 ± 6 Ma derived from the three oldest samples, within error of a previous U–Pb zircon age on the syn-sedimentary Plains sill. We interpret the Prichard xenotime as diagenetic in origin. Monazite from the Prichard Formation, originally thought to be detrital, yielded Cretaceous metamorphic ages. Xenotime from the McNamara and Garnet Range Formations and Pilcher Quartzite formed at about 1160–1050 Ma, several hundred million years after deposition, and probably also experienced Early Cretaceous growth. These xenotime overgrowths are interpreted as metamorphic–diagenetic in origin (i.e., derived during greenschist facies metamorphism elsewhere in the basin, but deposited in sub-greenschist facies rocks). Several xenotime grains are older detrital grains of igneous derivation. A previous study on the Revett Formation at the Spar Lake Ag–Cu deposit provides data for xenotime overgrowths in several ore zones formed by hydrothermal processes; herein, those results are compared with data from newly analyzed diagenetic, metamorphic, and magmatic xenotime overgrowths. The origin of a xenotime overgrowth is reflected in its rare-earth element (REE) pattern. Detrital (i.e., igneous) xenotime has a large negative Eu anomaly and is heavy rare-earth element (HREE)-enriched (similar to REE in igneous zircon). Diagenetic xenotime has a small negative Eu anomaly and flat HREE (Tb to Lu). Hydrothermal xenotime is depleted in light rare-earth element (LREE), has a small negative Eu anomaly, and decreasing HREE. Metamorphic xenotime is very LREE-depleted, has a very small negative Eu anomaly, and is strongly depleted in HREE (from Gd to Lu). Because these characteristics seem to be process related, they may be useful for interpretation of xenotime of unknown origin. The occurrence of 1.16–1.05 Ga metamorphic xenotime, in the apparent absence of pervasive deformation structures, suggests that the heating may be related to poorly understood regional heating due to broad regional underplating of mafic magma. These results may be additional evidence (together with published ages from metamorphic titanite, zircon, monazite, and garnet) for an enigmatic, Grenville-age metamorphic event that is more widely recognized in the southwestern and eastern United States.",
    url = "https://doi.org/10.1139/cjes-2014-0239",
    doi = "10.1139/cjes-2014-0239",
    openalex = "W2154878812",
    references = "doi102113econgeo10761143"
}

@article{tripathy2015radiometric,
    author = "Tripathy, Gyana Ranjan and Hannah, Judith L. and Stein, Holly J. and Geboy, Nicholas J. and Ruppert, Leslie F.",
    title = "Radiometric dating of marine-influenced coal using Re–Os geochronology",
    year = "2015",
    journal = "Earth and Planetary Science Letters",
    url = "https://doi.org/10.1016/j.epsl.2015.09.030",
    doi = "10.1016/j.epsl.2015.09.030",
    openalex = "W1839098611",
    pages = "13-23",
    volume = "432",
    references = "doi101016jearscirev200708008, doi101016s0009254103001992, doi1010292001gc000172, doi1010292008pa001607, doi101046j13653121200000295x, doi101098rstb19980195, doi1011300091761319900180533pcosro23co2, doi101144gslmem19900120101, doi1013060c9b238f171011d78645000102c1865d, doi10130694885688170411d78645000102c1865d"
}

Question: Why “Petrochronology”? Why add another term to an already cluttered scientific lexicon? Answer: Because petrologists and geochronologists need a term that describes the unique, distinctive way in which they apply geochronology to the study of igneous and metamorphic processes. Other terms just won’t do. Such evolution of language is natural and well-established. For instance, “Geochronology” was originally coined during the waning stages of the great Age-of-the-Earth debate as a means of distinguishing timescales relevant to Earth processes from timescales relevant to humans (Williams 1893). Eighty-eight years later, Berger and York (1981) coined the term “Thermochronology,” which has evolved as a branch of geochronology aimed at constraining thermal histories of rocks, where (typically) the thermally activated diffusive loss of a radiogenic daughter governs the ages we measure. Thermochronology may now be distinguished from “plain vanilla” geochronology, whose limited purpose, in the words of Reiners et al. (2005), is “…exclusively to determine a singular absolute stratigraphic or magmatic [or metamorphic] formation age, with little concern for durations or rates of processes” that give rise to these rocks. Neither of these terms describes what petrologists do with chronologic data. A single date is virtually useless in understanding the protracted history of magma crystallization or metamorphic pressure–temperature evolution. And we are not simply interested in thermal histories, but in chemical and baric evolution as well. Rather, we petrologists and geochronologists strive to understand rock-forming processes, and the rates at which they occur, by integrating numerous ages into the petrologic evolution of a rock. It is within this context that a new discipline, termed “Petrochronology”, has emerged1. In some sense petrochronology may be considered the sister of thermochronology: petrochronology typically focuses on the processes leading up to the formation of igneous and metamorphic rocks—the minerals and textures we observe and the processes that formed them—whereas thermochronology emphasizes cooling processes in the wake of igneous, metamorphic, and tectonic events. Typically petrochronology is “hot”, thermochronology is “cold”. While each field has its unique features, and while their disciplinary boundaries overlap, each complements the other. Any rock sample we study, whether igneous, sedimentary, or metamorphic, results from the transformation of one or more previous rocks. Petrologists and geochemists have found that such transformation rarely erases a rock’s memory completely, instead most samples contain relics from more than one stage of their evolution. Whether and how these affect an age determination is essentially a question of resolution—both spatial and chronometric—i.e., of isotopic and chemical analysis. Analytical efforts in petrochronology typically find that several stages or generations of mineral formation are evident in any single rock sample, in which case we conclude that such a rock does not have, sensu stricto, one age. In fact, one is led to wonder what the term “age” may signify in everyday geologic usage. It might seem clear what is meant, for example, by the age of a basaltic lava flow: the time of deposition or solidification. But what is the age of a meta-basalt? Does it refer to the point on the prograde path when its mineralogy and texture would define it as “metamorphic”, and no longer igneous? The pressure peak? The maximum temperature? The point on the retrograde path where mineralogy and chemistry no longer change measurably? And by what methods can that singular metamorphic age be measured? Actually, defining “an” age of a volcanic rock presents its own problems. How do we choose among the ages of initial melting, magma movement or rejuvenation, crystallization of antecrysts and duration of residence in a magma chamber, eruption, or solidification? And what does an age mean for a clastic rock, where each grain may have a slightly different parent, and materials may be reworked. The concept of “an age” really makes sense only within a defined petrogenetic context. This recognition leads us to a practical definition: Petrochronology is the branch of Earth science that is based on the study of rock samples and that links time (i.e., ages or duration) with specific rock-forming processes and their physical conditions. Petrochronology is founded in petrology and geochemistry, which define a petrogenetic context or delimit a specific process, to which chronometric data are then linked. 1 Several parts of this introduction are taken from a discussion that took place in the forum GEO-METAMORPHISM in June, 2013.

@article{doi102138rmg2017831,
    author = "Engi, Martin and Lanari, Pierre and Kohn, Matthew J.",
    title = "Significant Ages—An Introduction to Petrochronology",
    year = "2017",
    journal = "Reviews in Mineralogy and Geochemistry",
    abstract = "Question: Why “Petrochronology”? Why add another term to an already cluttered scientific lexicon? Answer: Because petrologists and geochronologists need a term that describes the unique, distinctive way in which they apply geochronology to the study of igneous and metamorphic processes. Other terms just won’t do. Such evolution of language is natural and well-established. For instance, “Geochronology” was originally coined during the waning stages of the great Age-of-the-Earth debate as a means of distinguishing timescales relevant to Earth processes from timescales relevant to humans (Williams 1893). Eighty-eight years later, Berger and York (1981) coined the term “Thermochronology,” which has evolved as a branch of geochronology aimed at constraining thermal histories of rocks, where (typically) the thermally activated diffusive loss of a radiogenic daughter governs the ages we measure. Thermochronology may now be distinguished from “plain vanilla” geochronology, whose limited purpose, in the words of Reiners et al. (2005), is “…exclusively to determine a singular absolute stratigraphic or magmatic [or metamorphic] formation age, with little concern for durations or rates of processes” that give rise to these rocks. Neither of these terms describes what petrologists do with chronologic data. A single date is virtually useless in understanding the protracted history of magma crystallization or metamorphic pressure–temperature evolution. And we are not simply interested in thermal histories, but in chemical and baric evolution as well. Rather, we petrologists and geochronologists strive to understand rock-forming processes, and the rates at which they occur, by integrating numerous ages into the petrologic evolution of a rock. It is within this context that a new discipline, termed “Petrochronology”, has emerged1. In some sense petrochronology may be considered the sister of thermochronology: petrochronology typically focuses on the processes leading up to the formation of igneous and metamorphic rocks—the minerals and textures we observe and the processes that formed them—whereas thermochronology emphasizes cooling processes in the wake of igneous, metamorphic, and tectonic events. Typically petrochronology is “hot”, thermochronology is “cold”. While each field has its unique features, and while their disciplinary boundaries overlap, each complements the other. Any rock sample we study, whether igneous, sedimentary, or metamorphic, results from the transformation of one or more previous rocks. Petrologists and geochemists have found that such transformation rarely erases a rock’s memory completely, instead most samples contain relics from more than one stage of their evolution. Whether and how these affect an age determination is essentially a question of resolution—both spatial and chronometric—i.e., of isotopic and chemical analysis. Analytical efforts in petrochronology typically find that several stages or generations of mineral formation are evident in any single rock sample, in which case we conclude that such a rock does not have, sensu stricto, one age. In fact, one is led to wonder what the term “age” may signify in everyday geologic usage. It might seem clear what is meant, for example, by the age of a basaltic lava flow: the time of deposition or solidification. But what is the age of a meta-basalt? Does it refer to the point on the prograde path when its mineralogy and texture would define it as “metamorphic”, and no longer igneous? The pressure peak? The maximum temperature? The point on the retrograde path where mineralogy and chemistry no longer change measurably? And by what methods can that singular metamorphic age be measured? Actually, defining “an” age of a volcanic rock presents its own problems. How do we choose among the ages of initial melting, magma movement or rejuvenation, crystallization of antecrysts and duration of residence in a magma chamber, eruption, or solidification? And what does an age mean for a clastic rock, where each grain may have a slightly different parent, and materials may be reworked. The concept of “an age” really makes sense only within a defined petrogenetic context. This recognition leads us to a practical definition: Petrochronology is the branch of Earth science that is based on the study of rock samples and that links time (i.e., ages or duration) with specific rock-forming processes and their physical conditions. Petrochronology is founded in petrology and geochemistry, which define a petrogenetic context or delimit a specific process, to which chronometric data are then linked. 1 Several parts of this introduction are taken from a discussion that took place in the forum GEO-METAMORPHISM in June, 2013.",
    url = "https://doi.org/10.2138/rmg.2017.83.1",
    doi = "10.2138/rmg.2017.83.1",
    openalex = "W2617228887",
    references = "doi102138rmg20178312, doi102138rmg2017832"
}

This paper reviews the basic principles of radiometric geochronology as implemented in a new software package called IsoplotR, which was designed to be free, flexible and future-proof. IsoplotR is free because it is written in non-proprietary languages (R, Javascript and HTML) and is released under the GPL license. The program is flexible because its graphical user interface (GUI) is separated from the command line functionality, and because its code is completely open for inspection and modification. To increase future-proofness, the software is built on free and platform-independent foundations that adhere to international standards, have existed for several decades, and continue to grow in popularity. IsoplotR currently includes functions for U-Pb, Pb-Pb, 40Ar/39Ar, Rb-Sr, Sm-Nd, Lu-Hf, Re-Os, U-Th-He, fission track and U-series disequilibrium dating. It implements isochron regression in two and three dimensions, visualises multi-aliquot datasets as cumulative age distributions, kernel density estimates and radial plots, and calculates weighted mean ages using a modified Chauvenet outlier detection criterion that accounts for the analytical uncertainties in heteroscedastic datasets. Overdispersion of geochronological data with respect to these analytical uncertainties can be attributed to either a proportional underestimation of the analytical uncertainties, or to an additive geological scatter term. IsoplotR keeps track of error correlations of the isotopic ratio measurements within aliquots of the same samples. It uses a statistical framework that will allow it to handle error correlations between aliquots in the future. Other ongoing developments include the implementation of alternative user interfaces and the integration of IsoplotR with other data reduction software.

@article{doi101016jgsf201804001,
    author = "Vermeesch, Pieter",
    title = "IsoplotR: A free and open toolbox for geochronology",
    year = "2018",
    journal = "Geoscience Frontiers",
    abstract = "This paper reviews the basic principles of radiometric geochronology as implemented in a new software package called IsoplotR, which was designed to be free, flexible and future-proof. IsoplotR is free because it is written in non-proprietary languages (R, Javascript and HTML) and is released under the GPL license. The program is flexible because its graphical user interface (GUI) is separated from the command line functionality, and because its code is completely open for inspection and modification. To increase future-proofness, the software is built on free and platform-independent foundations that adhere to international standards, have existed for several decades, and continue to grow in popularity. IsoplotR currently includes functions for U-Pb, Pb-Pb, 40Ar/39Ar, Rb-Sr, Sm-Nd, Lu-Hf, Re-Os, U-Th-He, fission track and U-series disequilibrium dating. It implements isochron regression in two and three dimensions, visualises multi-aliquot datasets as cumulative age distributions, kernel density estimates and radial plots, and calculates weighted mean ages using a modified Chauvenet outlier detection criterion that accounts for the analytical uncertainties in heteroscedastic datasets. Overdispersion of geochronological data with respect to these analytical uncertainties can be attributed to either a proportional underestimation of the analytical uncertainties, or to an additive geological scatter term. IsoplotR keeps track of error correlations of the isotopic ratio measurements within aliquots of the same samples. It uses a statistical framework that will allow it to handle error correlations between aliquots in the future. Other ongoing developments include the implementation of alternative user interfaces and the integration of IsoplotR with other data reduction software.",
    url = "https://doi.org/10.1016/j.gsf.2018.04.001",
    doi = "10.1016/j.gsf.2018.04.001",
    openalex = "W2796600848",
    references = "doi1010079789400941090, doi101007bf02288916, doi1010160012821x75900886, doi101016jchemgeo201204021, doi101016jepsl201304006, doi101016jgca200901015, doi101016s0012821x68800597, doi101038ngeo1475, doi101103physrevc41889, doi101111j147547541999tb00987x, doi101111j1751908x201600379x, doi101111j251761611982tb01195x, doi10111911632486, doi101126science1215507, doi1023071270335, openalexw2025327988, openalexw2797914455, openalexw2912219260"
}

It has been hypothesized that the overall size of-or efficiency of carbon export from-the biosphere decreased at the end of the Great Oxidation Event (GOE) (ca. 2,400 to 2,050 Ma). However, the timing, tempo, and trigger for this decrease remain poorly constrained. Here we test this hypothesis by studying the isotope geochemistry of sulfate minerals from the Belcher Group, in subarctic Canada. Using insights from sulfur and barium isotope measurements, combined with radiometric ages from bracketing strata, we infer that the sulfate minerals studied here record ambient sulfate in the immediate aftermath of the GOE (ca. 2,018 Ma). These sulfate minerals captured negative triple-oxygen isotope anomalies as low as ∼ -0.8‰. Such negative values occurring shortly after the GOE require a rapid reduction in primary productivity of >80%, although even larger reductions are plausible. Given that these data imply a collapse in primary productivity rather than export efficiency, the trigger for this shift in the Earth system must reflect a change in the availability of nutrients, such as phosphorus. Cumulatively, these data highlight that Earth's GOE is a tale of feast and famine: A geologically unprecedented reduction in the size of the biosphere occurred across the end-GOE transition.

@article{doi101073pnas1900325116,
    author = "Hodgskiss, Malcolm S.W. and Crockford, Peter W. and Peng, Yongbo and Wing, Boswell A. and Horner, Tristan J.",
    title = "A productivity collapse to end Earth’s Great Oxidation",
    year = "2019",
    journal = "Proceedings of the National Academy of Sciences",
    abstract = "It has been hypothesized that the overall size of-or efficiency of carbon export from-the biosphere decreased at the end of the Great Oxidation Event (GOE) (ca. 2,400 to 2,050 Ma). However, the timing, tempo, and trigger for this decrease remain poorly constrained. Here we test this hypothesis by studying the isotope geochemistry of sulfate minerals from the Belcher Group, in subarctic Canada. Using insights from sulfur and barium isotope measurements, combined with radiometric ages from bracketing strata, we infer that the sulfate minerals studied here record ambient sulfate in the immediate aftermath of the GOE (ca. 2,018 Ma). These sulfate minerals captured negative triple-oxygen isotope anomalies as low as ∼ -0.8‰. Such negative values occurring shortly after the GOE require a rapid reduction in primary productivity of >80\%, although even larger reductions are plausible. Given that these data imply a collapse in primary productivity rather than export efficiency, the trigger for this shift in the Earth system must reflect a change in the availability of nutrients, such as phosphorus. Cumulatively, these data highlight that Earth's GOE is a tale of feast and famine: A geologically unprecedented reduction in the size of the biosphere occurred across the end-GOE transition.",
    url = "https://doi.org/10.1073/pnas.1900325116",
    doi = "10.1073/pnas.1900325116",
    openalex = "W2967894559",
    references = "doi101016jearscirev201310006"
}

Abstract The Paleoproterozoic Bushveld Complex, including the world’s largest layered intrusion and host to world-class stratiform chromium, platinum group element, and vanadium deposits, is a remarkable natural laboratory for investigating the timescales of magmatic processes in the Earth’s crust. A framework for the emplacement, crystallization, and cooling of the Bushveld Complex based on integrated U–Pb zircon–baddeleyite–titanite–rutile geochronology is presented for samples of different rock types from the Bushveld Complex, including ultramafic and mafic cumulates, mineralized horizons, granitic rocks from the roof, and a carbonatite from the nearby alkaline Phalaborwa Complex. The results indicate that (1) the Bushveld Complex was built incrementally over an ∼5 Myr interval from 2060 to 2055 Ma with a peak in magma flux at c. 2055–2056 Ma, (2) U–Pb zircon crystallization ages do not decrease in an uninterrupted systematic manner from the base to the top of the intrusion, indicating that the Bushveld Complex does not represent the crystallized products of a single progressively filled and cooled magma chamber, and (3) U–Pb rutile dates constrain cooling of the intrusion at the level of the Critical Zone through ∼500 °C by 2053 Ma. The c. 2060 Ma Phalaborwa Complex (pyroxenite, syenite, carbonatite + Cu–Fe-phosphate–vermiculite deposits) represents one of the earliest manifestations of widespread Bushveld-related magmatism in the northern Kaapvaal craton. The extended range and out-of-sequence U–Pb zircon dates determined for a harzburgite from the Lower Zone (c. 2056 Ma), an orthopyroxenite from the Lower Critical Zone (c. 2057 Ma), and orthopyroxenites from the Upper Critical Zone (c. 2057–2060 Ma) are interpreted to indicate that the lower part of the Bushveld Complex developed through successive intrusions and accretion of sheet-like intrusions (sills), some intruded at different stratigraphic levels. Crystallization of the main volume of the Bushveld Complex, as represented by the thick gabbroic sequences of the Main Zone and Upper Zone, is constrained to a relatively narrow interval of time (∼1 Myr) at c. 2055–2056 Ma. Granites and granophyres in the roof, and a diorite in the uppermost Upper Zone, constitute the youngest igneous activity in the Bushveld Complex at c. 2055 Ma. Collectively, these results contribute to an emerging paradigm shift for the assembly of some ultramafic–mafic magmatic systems from the conventional ‘big tank’ model to an ‘amalgamated sill’ model. The volume–duration relationship determined for magmatism in the Bushveld Complex, when compared with timescales established for the assembly of other layered intrusions and more silica-rich plutonic–volcanic systems worldwide, is distinct and equivalent to those determined for Phanerozoic continental and oceanic flood basalts that constitute large igneous provinces. Emplacement of the 2055–2060 Ma Bushveld Complex corresponds to the end of the Lomagundi–Jatuli Event, the largest magnitude positive carbon isotope excursion in Earth history, and this temporal correlation suggests that there may have been a contribution from voluminous Bushveld ultramafic–mafic–silicic magmatism to disruptions in the global paleoenvironment.

@article{doi101093petrologyegaa107,
    author = "Scoates, James S. and Wall, Corey J. and Friedman, Richard M. and Weis, Dominique and Mathez, Edmond and VanTongeren, J. A.",
    title = "Dating the Bushveld Complex: Timing of Crystallization, Duration of Magmatism, and Cooling of the World’s Largest Layered Intrusion and Related Rocks",
    year = "2020",
    journal = "Journal of Petrology",
    abstract = "Abstract The Paleoproterozoic Bushveld Complex, including the world’s largest layered intrusion and host to world-class stratiform chromium, platinum group element, and vanadium deposits, is a remarkable natural laboratory for investigating the timescales of magmatic processes in the Earth’s crust. A framework for the emplacement, crystallization, and cooling of the Bushveld Complex based on integrated U–Pb zircon–baddeleyite–titanite–rutile geochronology is presented for samples of different rock types from the Bushveld Complex, including ultramafic and mafic cumulates, mineralized horizons, granitic rocks from the roof, and a carbonatite from the nearby alkaline Phalaborwa Complex. The results indicate that (1) the Bushveld Complex was built incrementally over an ∼5 Myr interval from 2060 to 2055 Ma with a peak in magma flux at c. 2055–2056 Ma, (2) U–Pb zircon crystallization ages do not decrease in an uninterrupted systematic manner from the base to the top of the intrusion, indicating that the Bushveld Complex does not represent the crystallized products of a single progressively filled and cooled magma chamber, and (3) U–Pb rutile dates constrain cooling of the intrusion at the level of the Critical Zone through ∼500 °C by 2053 Ma. The c. 2060 Ma Phalaborwa Complex (pyroxenite, syenite, carbonatite + Cu–Fe-phosphate–vermiculite deposits) represents one of the earliest manifestations of widespread Bushveld-related magmatism in the northern Kaapvaal craton. The extended range and out-of-sequence U–Pb zircon dates determined for a harzburgite from the Lower Zone (c. 2056 Ma), an orthopyroxenite from the Lower Critical Zone (c. 2057 Ma), and orthopyroxenites from the Upper Critical Zone (c. 2057–2060 Ma) are interpreted to indicate that the lower part of the Bushveld Complex developed through successive intrusions and accretion of sheet-like intrusions (sills), some intruded at different stratigraphic levels. Crystallization of the main volume of the Bushveld Complex, as represented by the thick gabbroic sequences of the Main Zone and Upper Zone, is constrained to a relatively narrow interval of time (∼1 Myr) at c. 2055–2056 Ma. Granites and granophyres in the roof, and a diorite in the uppermost Upper Zone, constitute the youngest igneous activity in the Bushveld Complex at c. 2055 Ma. Collectively, these results contribute to an emerging paradigm shift for the assembly of some ultramafic–mafic magmatic systems from the conventional ‘big tank’ model to an ‘amalgamated sill’ model. The volume–duration relationship determined for magmatism in the Bushveld Complex, when compared with timescales established for the assembly of other layered intrusions and more silica-rich plutonic–volcanic systems worldwide, is distinct and equivalent to those determined for Phanerozoic continental and oceanic flood basalts that constitute large igneous provinces. Emplacement of the 2055–2060 Ma Bushveld Complex corresponds to the end of the Lomagundi–Jatuli Event, the largest magnitude positive carbon isotope excursion in Earth history, and this temporal correlation suggests that there may have been a contribution from voluminous Bushveld ultramafic–mafic–silicic magmatism to disruptions in the global paleoenvironment.",
    url = "https://doi.org/10.1093/petrology/egaa107",
    doi = "10.1093/petrology/egaa107",
    openalex = "W3119818339",
    references = "doi101016jearscirev201310006, doi101093petrologyegy024"
}

Abstract To date, few isotope age constraints on primary oil migration have been reported. Here we present U-Pb dating and characterization of two fracture-filling, oil inclusion-bearing calcite veins hosted in the Paleocene siliciclastic mudstone source rocks in Subei Basin, China. Deposition age of the mudstone formation was estimated to be ca. 60.2–58.0 Ma. The first vein consists of two major phases: a microcrystalline-granular (MG) calcite phase, and a blocky calcite phase, each showing distinctive petrographic features, rare earth element patterns, and carbon and oxygen isotope compositions. The early MG phase resulted from local mobilization of host carbonates, likely associated with disequilibrium compaction over-pressuring or tectonic extension, whereas the late-filling blocky calcite phase was derived from overpressured oil-bearing fluids with enhanced fluid-rock interactions. Vein texture and fluorescence characteristics reveal at least two oil expulsion events, the former represented by multiple bitumen veinlets postdating the MG calcite generation, and the latter marked by blue-fluorescing primary oil inclusions synchronous with the blocky calcite cementation. The MG calcite yields a laser ablation–inductively coupled plasma–mass spectrometry U-Pb age of 55.6 ± 1.4 Ma, constraining the earliest timing of the early oil migration event. The blocky calcite gives a younger U-Pb age of 47.8 ± 2.3 Ma, analytically indistinguishable from the U-Pb age of 46.5 ± 1.7 Ma yielded by the second calcite vein. These two ages define the time of the late oil migration event, agreeing well with the age estimate of 49.7–45.2 Ma inferred from fluid-inclusion homogenization temperature and published burial models. Thermodynamic modeling shows that the oil inclusions were trapped at ~27.0–40.9 MPa, exceeding corresponding hydrostatic pressures (23.1–26.7 MPa), confirming mild-moderate overpressure created by oil generation-expulsion. This integrated study combining carbonate U-Pb dating and fluid-inclusion characterization provides a new approach for reconstructing pressure-temperature-composition-time points in petroleum systems.

@article{doi101130b358041,
    author = "Su, Ao and Chen, Honghan and Feng, Yuexing and Zhao, Jian‐xin",
    title = "LA-ICP-MS U-Pb dating and geochemical characterization of oil inclusion-bearing calcite cements: Constraints on primary oil migration in lacustrine mudstone source rocks",
    year = "2021",
    journal = "Geological Society of America Bulletin",
    abstract = "Abstract To date, few isotope age constraints on primary oil migration have been reported. Here we present U-Pb dating and characterization of two fracture-filling, oil inclusion-bearing calcite veins hosted in the Paleocene siliciclastic mudstone source rocks in Subei Basin, China. Deposition age of the mudstone formation was estimated to be ca. 60.2–58.0 Ma. The first vein consists of two major phases: a microcrystalline-granular (MG) calcite phase, and a blocky calcite phase, each showing distinctive petrographic features, rare earth element patterns, and carbon and oxygen isotope compositions. The early MG phase resulted from local mobilization of host carbonates, likely associated with disequilibrium compaction over-pressuring or tectonic extension, whereas the late-filling blocky calcite phase was derived from overpressured oil-bearing fluids with enhanced fluid-rock interactions. Vein texture and fluorescence characteristics reveal at least two oil expulsion events, the former represented by multiple bitumen veinlets postdating the MG calcite generation, and the latter marked by blue-fluorescing primary oil inclusions synchronous with the blocky calcite cementation. The MG calcite yields a laser ablation–inductively coupled plasma–mass spectrometry U-Pb age of 55.6 ± 1.4 Ma, constraining the earliest timing of the early oil migration event. The blocky calcite gives a younger U-Pb age of 47.8 ± 2.3 Ma, analytically indistinguishable from the U-Pb age of 46.5 ± 1.7 Ma yielded by the second calcite vein. These two ages define the time of the late oil migration event, agreeing well with the age estimate of 49.7–45.2 Ma inferred from fluid-inclusion homogenization temperature and published burial models. Thermodynamic modeling shows that the oil inclusions were trapped at \textasciitilde 27.0–40.9 MPa, exceeding corresponding hydrostatic pressures (23.1–26.7 MPa), confirming mild-moderate overpressure created by oil generation-expulsion. This integrated study combining carbonate U-Pb dating and fluid-inclusion characterization provides a new approach for reconstructing pressure-temperature-composition-time points in petroleum systems.",
    url = "https://doi.org/10.1130/b35804.1",
    doi = "10.1130/b35804.1",
    openalex = "W4200357946",
    references = "doi101016jchemgeo201905025"
}

Reliable estimation of ages and temporal correlations through the Quaternary Period (<2.58 Myr) have led to a better understanding of paleoclimatic changes. Various dating techniques applicable through the Quaternary have received significant impetus from paleoclimate community for high-resolution climatic reconstructions that are supported by robust chronological controls. Radiometric dating of Quaternary samples/archives have extensively progressed due to significant instrumentation developments. The Quaternary studies involve several radiometric dating techniques which include cosmogenic and anthropogenically produced radioisotopes. Radiocarbon (14C) is a cosmogenically produced radionuclide that has been frequently used to date recent archives. Previously, conventional β counting method for radiocarbon dating required ∼ 1 g of carbon extracted from the samples. However, with the introduction and development of Accelerator Mass spectrometry (AMS), it became possible to date these natural archives with a much smaller sample quantity. In addition to its application in 14C dating, AMS also led to a breakthrough in application of other cosmogenic isotopic systems (10Be, 26Al) to understand various earth surface processes (e.g., glacial retreats, denudation rates). The 210Pb dating technique is mainly used to study anthropogenic forcing on annual to decadal climatic changes. The measurement technique for 210Pb commenced with α detectors and involved tedious chemical separation and longer measurement times in attaining secular equilibrium. However, the gradual adoption of β and γ detectors led to rapid analysis with relatively shorter analysis times. This contribution aims to provide an overview of frequently used radiometric (14C, 10Be, 26Al, 210Pb and 137Cs) dating techniques in Quaternary studies and discusses the significant instrumental developments.

@article{doi101016jjaesx2022100091,
    author = "Banerji, Upasana S. and Goswami, Vineet and Joshi, Kumar Batuk",
    title = "Quaternary dating and instrumental development: An overview",
    year = "2022",
    journal = "Journal of Asian Earth Sciences X",
    abstract = "Reliable estimation of ages and temporal correlations through the Quaternary Period (<2.58 Myr) have led to a better understanding of paleoclimatic changes. Various dating techniques applicable through the Quaternary have received significant impetus from paleoclimate community for high-resolution climatic reconstructions that are supported by robust chronological controls. Radiometric dating of Quaternary samples/archives have extensively progressed due to significant instrumentation developments. The Quaternary studies involve several radiometric dating techniques which include cosmogenic and anthropogenically produced radioisotopes. Radiocarbon (14C) is a cosmogenically produced radionuclide that has been frequently used to date recent archives. Previously, conventional β counting method for radiocarbon dating required ∼ 1 g of carbon extracted from the samples. However, with the introduction and development of Accelerator Mass spectrometry (AMS), it became possible to date these natural archives with a much smaller sample quantity. In addition to its application in 14C dating, AMS also led to a breakthrough in application of other cosmogenic isotopic systems (10Be, 26Al) to understand various earth surface processes (e.g., glacial retreats, denudation rates). The 210Pb dating technique is mainly used to study anthropogenic forcing on annual to decadal climatic changes. The measurement technique for 210Pb commenced with α detectors and involved tedious chemical separation and longer measurement times in attaining secular equilibrium. However, the gradual adoption of β and γ detectors led to rapid analysis with relatively shorter analysis times. This contribution aims to provide an overview of frequently used radiometric (14C, 10Be, 26Al, 210Pb and 137Cs) dating techniques in Quaternary studies and discusses the significant instrumental developments.",
    url = "https://doi.org/10.1016/j.jaesx.2022.100091",
    doi = "10.1016/j.jaesx.2022.100091",
    openalex = "W4220667332",
    references = "doi101016jpalaeo201805005"
}

The scarcity of well-preserved and directly dateable sedimentary sequences is a major impediment to inferring the Earth’s paleo-environmental evolution. The authigenic mineral glauconite can potentially provide absolute stratigraphic ages for sedimentary sequences and constraints on paleo-depositional conditions. This requires improved approaches for measuring and interpreting glauconite formation ages. Here, glauconite from a Cretaceous shelfal sequence (Langenstein, northern Germany) was characterized using petrographical, geochemical (EMP), andmineralogical (XRD) screening methods before in situ Rb-Sr dating via LA-ICP-MS/MS. The obtained glauconite ages (~101 to 97 Ma) partly overlap with the depositional age of the Langenstein sequence (±3 Ma), but without the expected stratigraphic age progression, which we attribute to detrital and diagenetic illitic phase impurities inside the glauconites. Using a novel age deconvolution approach, which combines the new Rb-Sr dataset with published K-Ar ages, we recalculate the glauconite bulk ages to obtain stratigraphically significant ‘pure’ glauconite ages (~100 to 96 Ma). Thus, our results show that pristine ages can be preserved in mineralogically complex glauconite grains even under burial diagenetic conditions (T < 65 °C; <1500 m depth), confirming that glauconite could be a suitable archive for paleo-environmental reconstructions and direct sediment dating.

@article{doi103390min12070818,
    author = "Scheiblhofer, Esther and Moser, Ulrike and Löhr, Stefan and Wilmsen, Markus and Farkaš, Juraj and Gallhofer, Daniela and Bäckström, Alice Matsdotter and Zack, Thomas and Baldermann, Andre",
    title = "Revisiting Glauconite Geochronology: Lessons Learned from In Situ Radiometric Dating of a Glauconite-Rich Cretaceous Shelfal Sequence",
    year = "2022",
    journal = "Minerals",
    abstract = "The scarcity of well-preserved and directly dateable sedimentary sequences is a major impediment to inferring the Earth’s paleo-environmental evolution. The authigenic mineral glauconite can potentially provide absolute stratigraphic ages for sedimentary sequences and constraints on paleo-depositional conditions. This requires improved approaches for measuring and interpreting glauconite formation ages. Here, glauconite from a Cretaceous shelfal sequence (Langenstein, northern Germany) was characterized using petrographical, geochemical (EMP), andmineralogical (XRD) screening methods before in situ Rb-Sr dating via LA-ICP-MS/MS. The obtained glauconite ages (\textasciitilde 101 to 97 Ma) partly overlap with the depositional age of the Langenstein sequence (±3 Ma), but without the expected stratigraphic age progression, which we attribute to detrital and diagenetic illitic phase impurities inside the glauconites. Using a novel age deconvolution approach, which combines the new Rb-Sr dataset with published K-Ar ages, we recalculate the glauconite bulk ages to obtain stratigraphically significant ‘pure’ glauconite ages (\textasciitilde 100 to 96 Ma). Thus, our results show that pristine ages can be preserved in mineralogically complex glauconite grains even under burial diagenetic conditions (T < 65 °C; <1500 m depth), confirming that glauconite could be a suitable archive for paleo-environmental reconstructions and direct sediment dating.",
    url = "https://doi.org/10.3390/min12070818",
    doi = "10.3390/min12070818",
    openalex = "W4283644308",
    references = "doi101016jjsames2020102699"
}