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Journal articles on the topic 'K-Ar and 40Ar/39Ar geochronology'

Author: Grafiati

Published: 7 July 2024

Last updated: 31 July 2025

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1

Renne, Paul R. "Progress and Challenges in K-Ar and40Ar/39Ar Geochronology." Paleontological Society Papers 12 (October 2006): 47–66. http://dx.doi.org/10.1017/s1089332600001340.

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K-Ar and more recently the40Ar/39Ar variant are well established dating methods. The40Ar/39Ar method requires irradiation with neutrons, posing some complications that are greatly outweighed by the benefits. The40Ar/39Ar method is particularly powerful due to the availability of internal reliability criteria, the ability to analyze single crystals, and the amenability of the analyses to automation.40Ar/39Ar dating has the capability for unsurpassed precision and is applicable to the broadest range of geologic environments and time scales of any radioisotope dating technique. For chronostratigr

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2

Carter, Jack, Ryan B. Ickert, Darren F. Mark, Marissa M. Tremblay, Alan J. Cresswell, and David C. W. Sanderson. "Production of <sup>40</sup>Ar by an overlooked mode of <sup>40</sup>K decay with implications for K-Ar geochronology." Geochronology 2, no. 2 (2020): 355–65. http://dx.doi.org/10.5194/gchron-2-355-2020.

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Abstract. The decay of 40K to the stable isotopes 40Ca and 40Ar is used as a measure of time for both the K-Ca and K-Ar geochronometers, the latter of which is most generally utilized by the variant 40Ar∕39Ar system. The increasing precision of geochronology has forced practitioners to deal with the systematic uncertainties rooted in all radioisotope dating methods. A major component of these systematic uncertainties for the K-Ar and 40Ar∕39Ar techniques is imprecisely determined decay constants and an incomplete knowledge of the decay scheme of 40K. Recent geochronology studies question wheth

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Lentz, Carlin, Kathleen Thorne, Christopher R. M. McFarlane, and Douglas A. Archibald. "U-Pb, Ar-Ar, and Re-Os Geochronological Constraints on Multiple Magmatic–Hydrothermal Episodes at the Lake George Mine, Central New Brunswick." Minerals 10, no. 6 (2020): 566. http://dx.doi.org/10.3390/min10060566.

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The Lake George antimony mine was at one time North America’s largest producer of antimony. Despite being widely known for the antimony mineralization, the deposit also hosts a range of styles of mineralization such as multiple generations of W-Mo bearing quartz veins as well as a system of As-Au bearing quartz–carbonate veins. In situ U-Pb zircon geochronology, using LA ICP-MS, of the Lake George granodiorite yielded a weighted mean 206Pb/238U age of 419.6 ± 3.0 Ma. Step heating of phlogopite separated from the lamprophyre dykes produced a 40Ar/39Ar plateau segment date of 419.4 ± 1.4 Ma. Sin

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Okwueze, Odinaka, Kevin Konrad, and Tomas Capaldi. "New developments in incremental heating detrital ⁴⁰Ar∕³⁹Ar lithic (DARL) geochronology using Icelandic river sand." Geochronology 6, no. 4 (2024): 683–96. https://doi.org/10.5194/gchron-6-683-2024.

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Abstract. Iceland records over 15 million years of complex volcanism resulting from the intersection of a mid-ocean ridge and mantle plume upwelling. The Iceland mantle plume has been active for at least 70 Myr, with surface expressions in Greenland, the North Atlantic, and Iceland. The Iceland hotspot may exhibit periods of increased volcanic output linked to pulses of upwelling within the plume. Understanding Iceland's magmatic history and potential pulsation could provide key insights into dynamic topography driving changes in deep-water oceanic circulation, late Cenozoic climate change, an

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MacIntyre, D. G., and M. E. Villeneuve. "Geochronology of mid-Cretaceous to Eocene magmatism, Babine porphyry copper district, central British Columbia." Canadian Journal of Earth Sciences 38, no. 4 (2001): 639–55. http://dx.doi.org/10.1139/e00-107.

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New U/Pb and 40Ar/39Ar isotopic dating in the Babine porphyry copper district of central British Columbia documents three distinct magmatic events at 107104, 8578, and 5450 Ma. The earliest event involved emplacement of rhyolite domes into submarine volcanic rocks of the Rocky Ridge Formation. The rhyolite domes and related dacitic to basaltic volcanic rocks gave a UPb age of 107.9 ± 0.2 Ma and an 40Ar/39Ar age of 104.8 ± 1.2 Ma. The rhyolites, which were previously mapped as Eocene, are reinterpreted to be part of a previously unrecognized mid-Cretaceous cauldron subsidence complex. The r

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6

Reid, Anthony, Marnie Forster, Wolfgang Preiss, et al. "Complex ⁴⁰Ar ∕ ³⁹Ar age spectra from low-grade metamorphic rocks: resolving the input of detrital and metamorphic components in a case study from the Delamerian Orogen." Geochronology 4, no. 2 (2022): 471–500. http://dx.doi.org/10.5194/gchron-4-471-2022.

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Abstract. In this study, we provide 40Ar / 39Ar geochronology data from a suite of variably deformed rocks from a region of low-grade metamorphism within the Cambro–Ordovician Delamerian Orogen, South Australia. Low-grade metamorphic rocks such as these can contain both detrital minerals and minerals newly grown or partly recrystallised during diagenesis and metamorphism. Hence, they typically yield complex 40Ar / 39Ar age spectra that can be difficult to interpret. Therefore, we have undertaken furnace step heating 40Ar / 39Ar geochronology to obtain age spectra with many steps to allow for a

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Hart, Craig JR, and Mike Villeneuve. "Geochronology of Neogene alkaline volcanic rocks (Miles Canyon basalt), southern Yukon Territory, Canada: the relative effectiveness of laser 40Ar/39Ar and K-Ar geochronology." Canadian Journal of Earth Sciences 36, no. 9 (1999): 1495–507. http://dx.doi.org/10.1139/e99-049.

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Miles Canyon basalt is an informal term used to describe numerous exposures of young alkaline olivine basalt flows in southern Yukon. The volcanic rocks are part of the Northern Cordilleran volcanic province. K-Ar and Ar-Ar whole-rock dates indicate that the Miles Canyon succession of flows at the Whitehorse Rapids are clearly Late Miocene in age (ca. 8.4 Ma). The largest exposure of the Miles Canyon basalt occurs at the Alligator Lake volcanic complex where two nearly concordant Pliocene Ar-Ar dates indicate eruption at ca. 3.2 Ma. K-Ar analyses from other sites yield dates of 2.4 and 7.1 Ma

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8

VASCONCELOS, PAULO M., ARTUR T. ONOE, KOJI KAWASHITA, ADALBERTO J. SOARES, and WILSON TEIXEIRA. "40Ar/39Ar geochronology at the Instituto de Geociências, USP: instrumentation, analytical procedures, and calibration." Anais da Academia Brasileira de Ciências 74, no. 2 (2002): 297–342. http://dx.doi.org/10.1590/s0001-37652002000200008.

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Laser heating 40Ar/39Ar geochronology provides high analytical precision and accuracy, mum-scale spatial resolution, and statistically significant data sets for the study of geological and planetary processes. A newly commissioned 40Ar/39Ar laboratory at CPGeo/USP, São Paulo, Brazil, equips the Brazilian scientific community with a new powerful tool applicable to the study of geological and cosmochemical processes. Detailed information about laboratory layout, environmental conditions, and instrumentation provides the necessary parameters for the evaluation of the CPGeo/USP 40Ar/39Ar suitabili

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Wu, Meng, Liang Li, Jing-gui Sun, and Rui Yang. "Geology, geochemistry, and geochronology of the Laozuoshan gold deposit, Heilongjiang Province, Northeast China: implications for multiple gold mineralization events and geodynamic setting." Canadian Journal of Earth Sciences 55, no. 6 (2018): 604–19. http://dx.doi.org/10.1139/cjes-2018-0038.

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The Laozuoshan gold deposit, located in the central part of the Jiamusi Massif, is hosted by the contact zone between granitic complex and Proterzoic strata. In this study, we present the results of geochronology and geochemistry of ore-related granodiorite and diorite porphyry, and hydrothermal sericite 40Ar/39Ar dating. The granodiorite and diorite porphyry in the Laozuoshan gold deposit are calc-alkaline and high-K (calc-alkaline) series, which are enriched in LREE and LILE and depleted in HFSE, with no depletion of Eu. The geochronology data show that zircon U–Pb ages of the granodiorite a

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10

Radhakrishna, T., H. Maluski, J. G. Mitchell, and M. Joseph. "40Ar/39Ar and K/Ar geochronology of the dykes from the south Indian granulite terrain." Tectonophysics 304, no. 1-2 (1999): 109–29. http://dx.doi.org/10.1016/s0040-1951(98)00288-1.

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11

Dunlop, David J. "Grenvillia and Laurentia — a Precambrian Wilson cycle?" Canadian Journal of Earth Sciences 51, no. 3 (2014): 187–96. http://dx.doi.org/10.1139/cjes-2013-0101.

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John Tuzo Wilson coined the term “plate” in plate tectonics. He is famous for inventing transform boundaries, hot spot tracks, and the Wilson cycle of ocean birth, growth, and decline. Less well remembered is his work in the 1950s on tectonic and radiometric age provinces of the Canadian Shield, as part of which he fathered U/Pb geochronology in Canada. This work gave strong support to the notion of continental growth through accretion of successively younger terranes onto an ancient cratonic core. The present paper reviews how paleomagnetism can trace the motions of continents to test Wilson’

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12

Webster, Ewan R., Douglas A. Archibald, David R. M. Pattison, Jessica A. Pickett, and Joel C. Jansen. "Tectonic domains and exhumation history of the Omineca Belt in southeastern British Columbia from 40Ar/39Ar thermochronology." Canadian Journal of Earth Sciences 57, no. 8 (2020): 918–46. http://dx.doi.org/10.1139/cjes-2019-0131.

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A large geochronological data set comprising 40Ar/39Ar and K–Ar (hornblende, muscovite, biotite, and K-feldspar), Rb–Sr (muscovite), fission track (zircon and apatite) and U–Pb (zircon and monazite) dates has been compiled for the southern Kootenay Arc and western Purcell anticlinorium in the Omineca Belt of the Canadian Cordillera in southeastern British Columbia. New 40Ar/39Ar data for hornblende, muscovite, biotite, and alkali feldspar are presented and combined with data from other studies. We integrate these data with recent advances in the geology of the region to define three partially

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13

Riley, Teal R., and Kim B. Knight. "Age of Pre-Break-Up Gondwana Magmatism." Antarctic Science 13, no. 2 (2001): 99–110. http://dx.doi.org/10.1017/s0954102001000177.

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Extensive outpourings of basalt, and to a lesser extent rhyolite, are closely associated with continental break-up and plume–lithosphere interactions. The Gondwana supercontinent began to fragment during Early–Middle Jurassic times and was associated with the eruption of over three million km3 of dominantly basaltic magma. This intense magmatic episode is recorded in volcanic rocks of the Karoo (Africa), Ferrar (Antarctica) and Chon Aike (South America). K–Ar and Rb–Sr whole rock geochronology has consistently failed to produce reliable ages for these volcanic rocks, but in the last four years

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14

Marchev, Peter, Peter Kibarov, Richard Spikings, Maria Ovtcharova, István Márton, and Robert Moritz. "40Ar/39Ar and U-Pb geochronology of the Iran Tepe volcanic complex, Eastern Rhodopes." Geologica Balcanica 39, no. 3 (2010): 3–12. http://dx.doi.org/10.52321/geolbalc.39.3.3.

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The Iran Tepe volcanic complex occurs in the south-eastern part of the Eastern Rhodope massif. The rocks are represented by calc-alkaline and high-K calc-alkaline basaltic andesite to dacite epiclastics, lava flows and dikes, which are crosscut by andesitic and latitic dikes and rhyolitic dykes from the Planinets dyke swarm. Stratigraphic data and existing K/Ar ages suggest that the Iran Tepe volcanic complex is Upper Eocene (35-39 Ma), and is one of the oldest volcanic structures in the Eastern Rhodopes. However, new 40Ar/39Ar laser fusion and incremental step-heating experiments on biotites

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15

TAKAGI, Tetsuichi, and Atsushi KAMEI. "40Ar-39Ar and K-Ar geochronology for plutonic rocks in the central Abukuma Plateau, northeastern Japan." Journal of Mineralogical and Petrological Sciences 103, no. 5 (2008): 307–17. http://dx.doi.org/10.2465/jmps.071120.

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16

Fitch, F. J., P. J. Hooker, J. A. Miller, J. G. Mitchell, and R. T. Watkins. "Reconnaissance potassium–argon geochronology of the Suregei–Asille district, northern Kenya." Geological Magazine 122, no. 6 (1985): 609–22. http://dx.doi.org/10.1017/s0016756800032027.

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AbstractPotassium–argon dating of 44 samples of basalt lavas and pantelleritic ignimbrites provides a provisional chronology for the 1900-metre thick Cenozoic succession of the Suregei–Asille district, northeast of Lake Turkana. Volcanic rocks of the Asille Group range in age from late Oligocene (Chattian) to late Miocene (Tortonian). Data obtained from conventional K–Ar total-rock analysis of basalt samples are appraised statistically to indicate the presence of three periods of enhanced volcanism centred around 27, 17 and 11.5 Ma. Equivalent ages obtained from the pyroclastic pantellerites b

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17

Montemagni, Chiara, Chiara Montomoli, Salvatore Iaccarino, et al. "Dating protracted fault activities: microstructures, microchemistry and geochronology of the Vaikrita Thrust, Main Central Thrust zone, Garhwal Himalaya, NW India." Geological Society, London, Special Publications 481, no. 1 (2018): 127–46. http://dx.doi.org/10.1144/sp481.3.

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AbstractThe timing of shearing along the Vaikrita Thrust, the upper structural boundary of the Main Central Thrust Zone in the Garhwal Himalaya, was constrained by combined microstructural, microchemical and geochronological investigations. Three different biotite–muscovite growth and recrystallization episodes were observed: a relict mica-1; mica-2 along the main mylonitic foliation; and mica-3 in coronitic structures around garnet during its breakdown. Electron microprobe analyses of biotite showed chloritization and a bimodal composition of biotite-2 in one sample. Muscovite-2 and muscovite

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18

Delgado-Argote, L. A., M. López-Martínez, D. York, and C. M. Hall. "Geologic framework and geochronology of ultramafic complexes of southern Mexico." Canadian Journal of Earth Sciences 29, no. 7 (1992): 1590–604. http://dx.doi.org/10.1139/e92-125.

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In southern Mexico, discrete ultramafic intrusive bodies larger than 4 km2 are genetically related to their enclosing volcano-sedimentary terranes. These terranes are the Cuicateco and Guerrero, which include the Cuicateco and Tierra Caliente metamorphic complexes, respectively. Their basement is largely unknown, and the ultramafic masses previously have been interpreted as allochthonous dismembered ophiolites. To constrain the age of these accreted terranes, the geologic setting and 40Ar/39Ar ages are presented from the localities of Loma Baya – El Tamarindo, Guerrero, and San Pedro Limón, St

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19

Talukdar, Debojit, N. V. Chalapathi Rao, J. Amal Dev, J. K. Tomson, Alok Kumar, and Ashutosh Pandey. "Palaeoproterozoic Lamproite Pulses from the Eastern Dharwar Craton, Southern India: Some Geodynamic Implications." Journal Of The Geological Society Of India 101, no. 6 (2025): 919–24. https://doi.org/10.17491/jgsi/2025/174184.

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ABSTRACT The cratonic regions of the Indian Shield host numerous Precambrian lamproites. A majority of these lamproites are dated at Mesoproterozoic (1070-1434 Ma) using whole-rock 40Ar-39Ar, zircon U-Pb, and mica K-Ar and Rb-Sr geochronology methods. This paper reports the results of Sm-Nd (apatite) and U-Pb (rutile) geochronology on the lamproites from the Somavarigudem and Gundrapalle from the Ramadugu Lamproite Field, Eastern Dharwar Craton. The polychronous nature of the lamproite emplacement in the Eastern Dharwar Craton is illustrated by their new Palaeoproterozoic (2040±31 Ma and 2002±

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20

Sun, Yonggang, Zhongjie Yang, Mingliang Wang, Chengcheng Xie, Xusheng Chen, and Fanbo Meng. "Overprinting Mineralization in the Huoluotai Porphyry Cu (Mo) Deposit, NE China: Evidence from K-Feldspar Ar-Ar Geochronology and S-Pb Isotopes." Minerals 14, no. 9 (2024): 859. http://dx.doi.org/10.3390/min14090859.

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The Great Xing’an Range (GXR) is a significant belt of polymetallic deposits located in the eastern segment of the Central Asian Orogenic Belt. The recently found Huoluotai porphyry Cu (Mo) deposit is situated in the northern GXR region in northeastern (NE) China. The deposit has been studied extensively using field geology and geochronological methods, which have identified two distinct mineralization events. These events include an early occurrence of porphyry-type Cu (Mo) mineralization and a later occurrence of vein-type Cu mineralization. Prior geochronology investigations have determined

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Arancibia, G., S. J. Matthews, and C. Pérez de Arce. "K–Ar and 40Ar/39Ar geochronology of supergene processes in the Atacama Desert, Northern Chile: tectonic and climatic relations." Journal of the Geological Society 163, no. 1 (2006): 107–18. http://dx.doi.org/10.1144/0016-764904-161.

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22

Chetel, Lauren M., J. A. (Toni) Simo, and Brad S. Singer. "40Ar/39Ar geochronology and provenance of detrital K-feldspars, Ordovician, Upper Mississippi Valley." Sedimentary Geology 182, no. 1-4 (2005): 163–81. http://dx.doi.org/10.1016/j.sedgeo.2005.07.010.

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23

Harlaux, Matthieu, Daniel J. Kontak, Alan H. Clark, et al. "Depositing >1.5 Mt of Tin Within <1 m.y. of Initial Granitic Intrusion in the San Rafael Tin (-Copper) Deposit, Southeastern Peru." Economic Geology 118, no. 6 (2023): 1371–96. http://dx.doi.org/10.5382/econgeo.5021.

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Abstract The San Rafael Sn (-Cu) deposit, located in the Eastern Cordillera of southeast Peru, is one of the world’s largest cassiterite-bearing vein systems (&gt;1 Mt Sn produced since 1969). The deposit consists of a quartz-cassiterite-chlorite-sulfide lode system spatially associated with an upper Oligocene (ca. 24 Ma) S-type granitic pluton. Based on a revised paragenetic sequence for the deposit, we interpret the temporal setting of both magmatic (biotite, K-feldspar) and hydrothermal (muscovite, adularia, cassiterite) minerals analyzed by 40Ar/39Ar step-heating and U-Pb laser ablatio

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Segev, Amit. "40Ar/39Ar and K–Ar geochronology of Berriasian–Hauterivian and Cenomanian tectonomagmatic events in northern Israel: implications for regional stratigraphy." Cretaceous Research 30, no. 3 (2009): 810–28. http://dx.doi.org/10.1016/j.cretres.2009.01.003.

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Vetrov, Evgeny, Johan De Grave, Natalia Vetrova, et al. "Tectonic History of the South Tannuol Fault Zone (Tuva Region of the Northern Central Asian Orogenic Belt, Russia): Constraints from Multi-Method Geochronology." Minerals 10, no. 1 (2020): 56. http://dx.doi.org/10.3390/min10010056.

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In this study, we present zircon U/Pb, plagioclase and K-feldspar 40Ar/39Ar and apatite fission track (AFT) data along the South Tannuol Fault Zone (STFZ). Integrating geochronology and multi-method thermochronology places constraints on the formation and subsequent reactivation of the STFZ. Cambrian (~510 Ma) zircon U/Pb ages obtained for felsic volcanic rocks date the final stage of STFZ basement formation. Ordovician (~460–450 Ma) zircon U/Pb ages were obtained for felsic rocks along the structure, dating their emplacement and marking post-formational local magmatic activity along the STFZ.

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26

Hao, Tingchen. "The Role of Isotopic Geochronology in Earth Sciences." Academic Journal of Science and Technology 13, no. 2 (2024): 233–36. http://dx.doi.org/10.54097/ysmsrt05.

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Isotopic geochronology, a specialized field within isotopic geochemistry, has evolved through the interdisciplinary integration of geology, nuclear physics, and radiochemistry. By applying the principles of radioactive isotope decay, isotopic geochronology provides precise geological dating, forming scientific timelines for Earth's major evolutionary stages. This study offers a concise summary and discussion of isotopic dating principles, age representation methods, and the theories, applications, and formulas of widely used high-precision isotopic dating techniques. The primary isotopic datin

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BARROS, MÁRCIA APARECIDA DE SANT’ANA, ANA MARIA MIZUSAKI, RICARDO WESKA, ANDRÉ DE BORBA, FARID CHEMALE JR, and ELISON CARMO DA COSTA. "Petrografia, Geoquímica, Análises Isotópicas (Sr, Nd) e Geocronologia Ar-Ar dos Basaltos de Tapirapuã (Tangará da Serra, Mato Grosso, Brasil)." Pesquisas em Geociências 33, no. 2 (2006): 71. http://dx.doi.org/10.22456/1807-9806.19515.

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The basaltic flows from Tapirapuã Formation are exposed at Tangará da Serra region, 250 km from Cuiabá (MT) and the thickness can reach 310 meters. The basalts range from massive dark gray, with colunar disjunctions at the base to purple amygdaloidal at the top. They are generally fine-grained, however gabroics portions have been identified. In thin section the Tapirapuã basalts show subophitic texture. Chemical analyses in these rocks suggest tholeiitic compositions, within continental tectonic environment. There is an enrichment of light rare earth elements when compared to heavy rare earth

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McDOUGALL, IAN, and RONALD T. WATKINS. "Geochronology of the Nabwal Hills: a record of earliest magmatism in the northern Kenyan Rift Valley." Geological Magazine 143, no. 1 (2005): 25–39. http://dx.doi.org/10.1017/s0016756805001184.

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The Nabwal Hills, northeast of Lake Turkana, contain a record of magmatism associated with the initiation and early development of the East African Rift System in northernmost Kenya. The predominantly volcanic Asille Group, 1400 m thick, directly overlies metamorphic basement and comprises a sequence of basaltic lava flows with significant intervals of rhyolitic pyroclastic units, and minor intercalations of fluviatile sediments. The basement gneisses yield K–Ar cooling ages on biotite of 510 and 522 Ma, typically Pan-African. The 40Ar–39Ar ages on alkali feldspar crystals from the rhyolitic u

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Zhang, Shaohua, Chiyang Liu, Jianqiang Wang, et al. "Zircon U-Pb-Hf Isotopes, Biotite 40Ar/39Ar Geochronology, and Whole-Rock Geochemistry of the Baogeqi Gabbro in the Northern Alxa, Southernmost Central Asian Orogenic Belt." Minerals 12, no. 5 (2022): 656. http://dx.doi.org/10.3390/min12050656.

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The final closure time of the Paleo-Asian Ocean and the Permo-Carboniferous tectonic settings in the northern Alxa are very important but controversial tectonic issues. The geochronology and petrogenesis of mafic igneous rocks are superior in clarifying regional tectonic settings. Here, we report on zircon U-Pb-Hf isotopes, biotite 40Ar/39Ar geochronology and whole-rock geochemical data of the hornblende gabbro from the Baogeqi gabbro pluton in the northern Alxa. The LA-ICP MS U-Pb analysis of zircon grains from the hornblende gabbro yield a weighted mean age of 262.7 ± 2.3 Ma (2σ, MSWD = 0.74

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Liu, Zhenjiang, Shaobo Cheng, Changrong Liu, Benjie Gu, and Yushan Xue. "Geochronology and Genesis of the Shuigou Gold Deposit, Qixia-Penglai-Fushan Metallogenic Area, Jiaodong Peninsula, Eastern China: Constraints from SHRIMP U-Pb, 40Ar/39Ar Age, and He-Ar Isotopes." Minerals 15, no. 1 (2024): 14. https://doi.org/10.3390/min15010014.

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The Jiaodong Peninsula is renowned for its significant gold reserves, which exceed 4500 tons. In this study, we conducted zircon SHRIMP U-Pb dating, 40Ar/39Ar geochronology, electron probe microanalysis (EPMA) analysis, and He-Ar isotope analysis on samples from the Shuigou gold deposit located in the Qixia-Penglai-Fushan metallogenic area of central Jiaodong. This quartz vein-type gold deposit is characterized by three mineralization stages: (I) the quartz-pyrite stage, (II) the quartz-polymetallic sulfide stage, and (III) the calcite stage. In stages I and II, gold primarily exists as native

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Guo, Jian, Youyue Lu, Jianming Fu, Zhengwei Qin, Yongyun Ning, and Zunzun Zhang. "Geology and Geochronology of the Maozaishan Sn Deposit, Hunan Province: Constraints from Zircon U–Pb and Muscovite Ar–Ar Dating." Minerals 9, no. 12 (2019): 773. http://dx.doi.org/10.3390/min9120773.

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The Maozaishan Sn deposit, located south of the Dayishan ore field in the Nanling Range, is a newly explored greisen-type Sn deposit. Two muscovite samples from tin-bearing ores yielded 40Ar/39Ar plateau ages of 154.7 ± 1.1 Ma (Mean standard weighted deviation (MSWD) = 0.48) and 152.6 ± 0.7 Ma (MSWD = 0.25), respectively. Zircon U–Pb dating result of fine-grained biotite monzogranite in the Maozaishan mining area shows that these zircon grains can be subdivided into two populations, with ages of 154.2 ± 2.0 Ma (MSWD = 0.51) and 159.6 ± 1.9 Ma (MSWD = 0.09), respectively, indicating that the mo

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Picazo, Suzanne M., Tanya A. Ewing, and Othmar Müntener. "Paleocene metamorphism along the Pennine–Austroalpine suture constrained by U–Pb dating of titanite and rutile (Malenco, Alps)." Swiss Journal of Geosciences 112, no. 2-3 (2019): 517–42. http://dx.doi.org/10.1007/s00015-019-00346-1.

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Abstract We present in situ rutile and titanite U–Pb geochronology for three samples from the Ur breccia, which forms the boundary between the Malenco unit and the Margna nappe (Eastern Central Alps) near Pass d’Ur in southeast Switzerland. These sampled both oceanic brecciated material and a blackwall reaction zone in contact with a micaschist and serpentinized peridotite. Peak temperatures during Alpine metamorphism in these units were ~ 460 ± 30 °C. Textural observations combined with new geochronological data indicate that rutile and titanite both grew below their closure temperatures duri

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Li, Yang, and Pieter Vermeesch. "Short communication: Inverse isochron regression for Re–Os, K–Ca and other chronometers." Geochronology 3, no. 2 (2021): 415–20. http://dx.doi.org/10.5194/gchron-3-415-2021.

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Abstract. Conventional Re–Os isochrons are based on mass spectrometric estimates of 187Re/188Os and 187Os/188Os, which often exhibit strong error correlations that may obscure potentially important geological complexity. Using an approach that is widely accepted in 40Ar/39Ar and U–Pb geochronology, we here show that these error correlations are greatly reduced by applying a simple change of variables, using 187Os as a common denominator. Plotting 188Os/187Os vs. 187Re/187Os produces an “inverse isochron”, defining a binary mixing line between an inherited Os component whose 188Os/187Os ratio i

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Terhune, Patrick J., Jeffrey A. Benowitz, Jeffrey M. Trop, Paul B. O’Sullivan, Robert J. Gillis, and Jeffrey T. Freymueller. "Cenozoic tectono-thermal history of the southern Talkeetna Mountains, Alaska: Insights into a potentially alternating convergent and transform plate margin." Geosphere 15, no. 5 (2019): 1539–76. http://dx.doi.org/10.1130/ges02008.1.

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Abstract The Mesozoic–Cenozoic convergent margin history of southern Alaska has been dominated by arc magmatism, terrane accretion, strike-slip fault systems, and possible spreading-ridge subduction. We apply 40Ar/39Ar, apatite fission-track (AFT), and apatite (U-Th)/He (AHe) geochronology and thermochronology to plutonic and volcanic rocks in the southern Talkeetna Mountains of Alaska to document regional magmatism, rock cooling, and inferred exhumation patterns as proxies for the region’s deformation history and to better delineate the overall tectonic history of southern Alaska. High-temper

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Zhou, Xiaolong, Klaudia Kuiper, Jan Wijbrans, Katharina Boehm, and Pieter Vroon. "Eruptive history and <sup>40</sup>Ar∕<sup>39</sup>Ar geochronology of the Milos volcanic field, Greece." Geochronology 3, no. 1 (2021): 273–97. http://dx.doi.org/10.5194/gchron-3-273-2021.

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Abstract. High-resolution geochronology is essential for determining the growth rate of volcanoes, which is one of the key factors for establishing the periodicity of volcanic eruptions. However, there are less high-resolution eruptive histories (> 106 years) determined for long-lived submarine arc volcanic complexes than for subaerial complexes, since submarine volcanoes are far more difficult to observe than subaerial ones. In this study, high-resolution geochronology and major-element data are presented for the Milos volcanic field (VF) in the South Aegean Volcanic Arc, Greece. The Milos

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Arancibia, Gloria, Stephen J. Matthews, Paula Cornejo, Carlos Pérez de Arce, José I. Zuluaga, and Stabro Kasaneva. "40Ar/39Ar and K–Ar geochronology of magmatic and hydrothermal events in a classic low-suphidation epithermal bonanza deposit: El Peñon, northern Chile." Mineralium Deposita 41, no. 5 (2006): 505–16. http://dx.doi.org/10.1007/s00126-006-0078-2.

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Jicha, B. R., M. L. Coombs, A. T. Calvert, and B. S. Singer. "Geology and 40Ar/39Ar geochronology of the medium- to high-K Tanaga volcanic cluster, western Aleutians." Geological Society of America Bulletin 124, no. 5-6 (2012): 842–56. http://dx.doi.org/10.1130/b30472.1.

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Walker, Jordan T., Andres Aslan, Rex D. Cole, and Michael T. Heizler. "New age constraints on the Late Cretaceous lower Williams Fork Formation, Coal Canyon, Colorado." Mountain Geologist 58, no. 1 (2021): 5–26. http://dx.doi.org/10.31582/rmag.mg.58.1.5.

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The precise age of terrestrial sediments in the Late Cretaceous Williams Fork Formation of western Colorado is poorly constrained due to a paucity of radiometric data. Sanidine and zircon dating of a volcanic ash encased in coal (i.e., the Coal Canyon ash) within the Cameo-Wheeler coal zone of the lower Williams Fork Formation in Coal Canyon, Colorado provides an important new age constraint for the southwestern Piceance Basin. A 10-30 cm thick, light gray, clayey mudstone encased in coal was sampled for both zircon U-Pb and sanidine 40Ar/39Ar geochronology. The presence of numerous euhedral z

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OLIVEROS, VERóNICA, LUIS AGUIRRE, DIEGO MORATA, et al. "Geochronology of very low-grade Mesozoic Andean metabasites; an approach through the K–Ar, 40Ar/39Ar and U–Pb LA-MC-ICP-MS methods." Journal of the Geological Society 165, no. 2 (2008): 579–84. http://dx.doi.org/10.1144/0016-76492007-113.

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Holm, Daniel, and David Schneider. "40Ar/39Ar evidence for ca. 1800 Ma tectonothermal activity along the Great Falls tectonic zone, central Montana." Canadian Journal of Earth Sciences 39, no. 12 (2002): 1719–28. http://dx.doi.org/10.1139/e02-069.

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Late Paleoproterozoic (19001600 Ma) tectonothermal activity on all borders of the Archean Wyoming Province has long been established by low-precision KAr and RbSr studies. However, recent tectonic models advanced for supercontinent aggregation require improved constraints on the timing of tectonothermal activity along major boundaries. On its northwestern boundary, the Great Falls tectonic zone separates the Archean Wyoming and Hearne provinces. Recently published U/Pb ages and geochemical data reveal the presence of a Paleoproterozoic (ca. 1860 Ma) marginal-arc magmatic complex along a por

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Nikolenko, Evgeny I., Konstantin V. Lobov, Alexey M. Agashev, et al. "40Ar/39Ar Geochronology and New Mineralogical and Geochemical Data from Lamprophyres of Chompolo Field (South Yakutia, Russia)." Minerals 10, no. 10 (2020): 886. http://dx.doi.org/10.3390/min10100886.

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The alkaline igneous rocks of the Chompolo field (Aldan shield, Siberian craton), previously defined as kimberlites or lamproites, are more correctly classified as low-Ti lamprophyres. The emplacement age of the Ogonek pipe (137.8 ± 1.2 Ma) and the Aldanskaya dike (157.0 ± 1.6 Ma) was obtained using 40Ar/39Ar K-richterite dating. The Chompolo rocks contain abundant xenocrysts of mantle minerals (chromium-rich pyropic garnets, Cr-diopsides, spinels, etc.). The composition of the mantle xenocrysts indicates the predominance of spinel and garnet–spinel lherzolites, while the presence of garnet lh

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Levent, Gülşah, and Durmuş Boztuğ. "Investigation of Intrusive Rocks in the Çambaşı Plateau and Bektaşyayla Region Located South of Ordu Using 40Ar/39Ar Petrology and Geothermochronology Methods." American Journal of Art and Design 10, no. 2 (2025): 47–60. https://doi.org/10.11648/j.ajad.20251002.14.

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This research focuses on elucidating the tectonic processes in the Eastern Pontides by investigating the Çambaşı Quartz Syenite and Bektaş Yaylası Quartz Monzonite, situated south of Ordu province in northeastern Turkey. To achieve this, mineralogical and petrographic characteristics of the acidic granitoids were analyzed alongside 40Ar/39Ar biotite age dating and comprehensive whole-rock and mineral geochemical analyses. Samples collected from Bektaş Yaylası Quartz Monzodiorite and Çambaşı Quartz Syenite underwent crushing, grinding, sieving, and washing to prepare for age determination. The

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Feng, R., R. Kerrich, S. McBride, and E. Farrar. "40Ar/39Ar age constraints on the thermal history of the Archean Abitibi greenstone belt and the Pontiac Subprovince: implications for terrane collision, differential uplift, and overprinting of gold deposits." Canadian Journal of Earth Sciences 29, no. 7 (1992): 1389–411. http://dx.doi.org/10.1139/e92-112.

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40Ar/39Ar mineral age spectra of granitic and metamorphic rocks, in conjunction with existing conventional zircon geochronology, indicate that at least two major late Archean thermal events affected tectonic blocks of the Abitibi Southern Volcanic Zone (SVZ) and the juxtaposed Pontiac Subprovince. The earlier thermal activity (2690–2670 Ma) was accompanied by the intrusion of voluminous syntectonic plutons and caused low-pressure, greenschist-facies metamorphism in the SVZ and intermediate-pressure metamorphism in the Pontiac Subprovince. The second thermal event (2660–2630 Ma) was coeval with

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Boehm, Katharina M., Klaudia F. Kuiper, Bora Uzel, Pieter Z. Vroon, and Jan R. Wijbrans. "Volcanism straddling the Miocene–Pliocene boundary on Patmos and Chiliomodi islands (southeastern Aegean Sea): insights from new ⁴⁰Ar ∕ ³⁹Ar ages." Geochronology 5, no. 2 (2023): 391–403. http://dx.doi.org/10.5194/gchron-5-391-2023.

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Abstract. The island of Patmos, in the eastern Aegean Sea, consists almost entirely of late Miocene to Pliocene volcanic rocks. The magmatism in the Aegean is governed by subduction of the African plate below the Eurasian plate, back-arc extension, slab rollback, slab edge processes and westward extrusion of central Anatolia to the west along the Northern Anatolian Fault into the Aegean domain. The evolution of the Aegean basin is that of a back-arc setting, with a southerly trend in the locus of both convergent tectonics and back-arc stretching, allowing intermittent upwelling of arc, lithosp

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Dokuz, Abdurrahman, Faruk Aydin, and Orhan Karslı. "Postcollisional transition from subduction- to intraplate-type magmatism in the eastern Sakarya zone, Turkey: Indicators of northern Neotethyan slab breakoff." GSA Bulletin 131, no. 9-10 (2019): 1623–42. http://dx.doi.org/10.1130/b31993.1.

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Abstract Postcollisional magmatism in the eastern Sakarya zone was recorded by voluminous basic volcanism and repeated plutonism during the early Cenozoic. The temporal and geochemical evolution of these magmatic rocks is important for understanding the possible geodynamic history of the Sakarya zone. Here, we investigated three representative plutons lying between the towns of Çamlıhemşin (Rize) and İspir (Erzurum), Turkey. These are largely composed of medium-K gabbroic diorites (Marselavat Pluton), shoshonitic monzonites (Güllübağ Pluton), and high-K granites (Ayder Pluton). We present whol

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Leitch, C. H. B., P. van der Heyden, C. I. Godwin, R. L. Armstrong, and J. E. Harakal. "Geochronometry of the Bridge River Camp, southwestern British Columbia." Canadian Journal of Earth Sciences 28, no. 2 (1991): 195–208. http://dx.doi.org/10.1139/e91-019.

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Mineralization at the Bralorne mesothermal gold vein deposit is closely related to a suite of early Late Cretaceous to early Tertiary dykes. Premineral albitite dykes (91.4 ± 1.4 Ma by U–Pb on zircons) and postmineral lamprophyre dykes (43.5 ± 1.5 Ma by K–Ar on biotite) set definite age limits on the mineralizing event. A late intra- to post-mineral green hornblende dyke set (85.7 ± 3.0 Ma by K–Ar on hornblende) that forms a transitional series to the albitites may further restrict the age. Thus, mineralization occurred long after emplacement of the host Bralorne intrusions, dated as Early Per

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Petronis, Michael S., John W. Geissman, John S. Oldow, and William C. McIntosh. "Paleomagnetic and 40Ar/39Ar geochronologic data bearing on the structural evolution of the Silver Peak extensional complex, west-central Nevada." GSA Bulletin 114, no. 9 (2002): 1108–30. http://dx.doi.org/10.1130/0016-7606(2002)114<1108:paaagd>2.0.co;2.

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Abstract The Silver Peak extensional complex, located in the Silver Peak Range of west- central Nevada, is a displacement-transfer system linking the Furnace Creek–Fish Lake Valley fault system and transcurrent faults of the central Walker Lane. Late Neogene, northwest-directed motion of an upper plate, composed of lower Paleozoic sedimentary rocks and late Tertiary volcanic and volcaniclastic strata, exhumed a lower-plate assemblage of metamorphic tectonites with Proterozoic and Mesozoic protoliths. Paleomagnetic investigation of Miocene–Pliocene pyroclastic and sedimentary rocks of the upper

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Wilson, N. S. F., M. Zentilli, P. H. Reynolds, and R. Boric. "Age of mineralization by basinal fluids at the El Soldado manto-type copper deposit, Chile: 40Ar/39Ar geochronology of K-feldspar." Chemical Geology 197, no. 1-4 (2003): 161–76. http://dx.doi.org/10.1016/s0009-2541(02)00350-9.

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Zhang, Yong, Jing-Gui Sun, Shu-Wen Xing, and Zeng-Jie Zhang. "Geochronology and geochemistry of the Cuihongshan Fe-polymetallic deposit, northeastern China: implications for ore genesis and tectonic setting." Canadian Journal of Earth Sciences 55, no. 5 (2018): 475–89. http://dx.doi.org/10.1139/cjes-2017-0178.

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The Lesser Xing’an Range is located in the eastern segment of the Central Asian Orogenic Belt. It hosts an important polymetallic metallogenic belt that contains more than 20 large- to small-scale porphyry Mo, epithermal Au, and skarn Fe-polymetallic deposits. The Cuihongshan Fe-polymetallic deposit is one of the largest polymetallic deposits in northeastern China. To better understand the formation of the Cuihongshan Fe-polymetallic deposit, we investigated the geological characteristics of the Cuihongshan deposit and applied geochemistry and geochronology to constrain the timing of the miner

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Li, Huan, Kotaro Yonezu, Koichiro Watanabe, and Thomas Tindell. "Fluid origin and migration of the Huangshaping W–Mo polymetallic deposit, South China: Geochemistry and 40Ar/39Ar geochronology of hydrothermal K-feldspars." Ore Geology Reviews 86 (June 2017): 117–29. http://dx.doi.org/10.1016/j.oregeorev.2017.02.005.

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