Artigos de revistas: "Astrochronology"

1

Okada, Makoto. "A commentary on ^|^ldquo;Astrochronology^|^rdquo;". Journal of the Sedimentological Society of Japan 47, n.º 47 (1998): 113–18. http://dx.doi.org/10.4096/jssj1995.47.113.

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FISCHER, ALFRED G., FREDERIK J. HILGEN e ROBERT E. GARRISON. "Mediterranean contributions to cyclostratigraphy and astrochronology". Sedimentology 56, n.º 1 (janeiro de 2009): 63–94. http://dx.doi.org/10.1111/j.1365-3091.2008.01011.x.

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Zeebe, Richard E., e Lucas J. Lourens. "Solar System chaos and the Paleocene–Eocene boundary age constrained by geology and astronomy". Science 365, n.º 6456 (29 de agosto de 2019): 926–29. http://dx.doi.org/10.1126/science.aax0612.

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Astronomical calculations reveal the Solar System’s dynamical evolution, including its chaoticity, and represent the backbone of cyclostratigraphy and astrochronology. An absolute, fully calibrated astronomical time scale has hitherto been hampered beyond ~50 million years before the present (Ma) because orbital calculations disagree before that age. Here, we present geologic data and a new astronomical solution (ZB18a) showing exceptional agreement from ~58 to 53 Ma. We provide a new absolute astrochronology up to 58 Ma and a new Paleocene–Eocene boundary age (56.01 ± 0.05 Ma). We show that the Paleocene–Eocene Thermal Maximum (PETM) onset occurred near a 405-thousand-year (kyr) eccentricity maximum, suggesting an orbital trigger. We also provide an independent PETM duration (170 ± 30 kyr) from onset to recovery inflection. Our astronomical solution requires a chaotic resonance transition at ~50 Ma in the Solar System’s fundamental frequencies.

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4

Huang, Chunju, James G. Ogg e David B. Kemp. "Cyclostratigraphy and astrochronology: Case studies from China". Palaeogeography, Palaeoclimatology, Palaeoecology 560 (dezembro de 2020): 110017. http://dx.doi.org/10.1016/j.palaeo.2020.110017.

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Drury, Anna Joy, Thomas Westerhold, David Hodell e Ursula Röhl. "Reinforcing the North Atlantic backbone: revision and extension of the composite splice at ODP Site 982". Climate of the Past 14, n.º 3 (8 de março de 2018): 321–38. http://dx.doi.org/10.5194/cp-14-321-2018.

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Abstract. Ocean Drilling Program (ODP) Site 982 represents a key location for understanding the evolution of climate in the North Atlantic over the past 12 Ma. However, concerns exist about the validity and robustness of the underlying stratigraphy and astrochronology, which currently limits the adequacy of this site for high-resolution climate studies. To resolve this uncertainty, we verify and extend the early Pliocene to late Miocene shipboard composite splice at Site 982 using high-resolution XRF core scanning data and establish a robust high-resolution benthic foraminiferal stable isotope stratigraphy and astrochronology between 8.0 and 4.5 Ma. Splice revisions and verifications resulted in ∼ 11 m of gaps in the original Site 982 isotope stratigraphy, which were filled with 263 new isotope analyses. This new stratigraphy reveals previously unseen benthic δ18O excursions, particularly prior to 6.65 Ma. The benthic δ18O record displays distinct, asymmetric cycles between 7.7 and 6.65 Ma, confirming that high-latitude climate is a prevalent forcing during this interval. An intensification of the 41 kyr beat in both the benthic δ13C and δ18O is also observed ∼ 6.4 Ma, marking a strengthening in the cryosphere–carbon cycle coupling. A large ∼ 0.7 ‰ double excursion is revealed ∼ 6.4–6.3 Ma, which also marks the onset of an interval of average higher δ18O and large precession and obliquity-dominated δ18O excursions between 6.4 and 5.4 Ma, coincident with the culmination of the late Miocene cooling. The two largest benthic δ18O excursions ∼ 6.4–6.3 Ma and TG20/22 coincide with the coolest alkenone-derived sea surface temperature (SST) estimates from Site 982, suggesting a strong connection between the late Miocene global cooling, and deep-sea cooling and dynamic ice sheet expansion. The splice revisions and revised astrochronology resolve key stratigraphic issues that have hampered correlation between Site 982, the equatorial Atlantic and the Mediterranean. Comparisons of the revised Site 982 stratigraphy to high-resolution astronomically tuned benthic δ18O stratigraphies from ODP Site 926 (equatorial Atlantic) and Ain el Beida (north-western Morocco) show that prior inconsistencies in short-term excursions are now resolved. The identification of key new cycles at Site 982 further highlights the requirement for the current scheme for late Miocene marine isotope stages to be redefined. Our new integrated deep-sea benthic stable isotope stratigraphy and astrochronology from Site 982 will facilitate future high-resolution late Miocene to early Pliocene climate research.

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Gong, Zheng, e Mingsong Li. "Astrochronology of the Ediacaran Shuram carbon isotope excursion, Oman". Earth and Planetary Science Letters 547 (outubro de 2020): 116462. http://dx.doi.org/10.1016/j.epsl.2020.116462.

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7

Hüsing, S. K., A. Cascella, F. J. Hilgen, W. Krijgsman, K. F. Kuiper, E. Turco e D. Wilson. "Astrochronology of the Mediterranean Langhian between 15.29 and 14.17Ma". Earth and Planetary Science Letters 290, n.º 3-4 (fevereiro de 2010): 254–69. http://dx.doi.org/10.1016/j.epsl.2009.12.002.

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8

Meyers, Stephen R. "Seeing red in cyclic stratigraphy: Spectral noise estimation for astrochronology". Paleoceanography 27, n.º 3 (setembro de 2012): n/a. http://dx.doi.org/10.1029/2012pa002307.

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Wu, Huaichun, Shihong Zhang, Ganqing Jiang, Tianshui Yang, Junhua Guo e Haiyan Li. "Astrochronology for the Early Cretaceous Jehol Biota in northeastern China". Palaeogeography, Palaeoclimatology, Palaeoecology 385 (setembro de 2013): 221–28. http://dx.doi.org/10.1016/j.palaeo.2013.05.017.

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10

Baksi, Ajoy K. "Concordant sea-floor spreading rates obtained from geochronology, astrochronology and space geodesy". Geophysical Research Letters 21, n.º 2 (15 de janeiro de 1994): 133–36. http://dx.doi.org/10.1029/93gl03534.

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11

Martinez, Mathieu, Roque Aguado, Miguel Company, Jose Sandoval e Luis O'Dogherty. "Integrated astrochronology of the Barremian Stage (Early Cretaceous) and its biostratigraphic subdivisions". Global and Planetary Change 195 (dezembro de 2020): 103368. http://dx.doi.org/10.1016/j.gloplacha.2020.103368.

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12

Hilgen e Krijgsman. "Cyclostratigraphy and astrochronology of the Tripoli diatomite formation (pre-evaporite Messinian, Sicily, Italy)". Terra Nova 11, n.º 1 (janeiro de 1999): 16–22. http://dx.doi.org/10.1046/j.1365-3121.1999.00221.x.

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13

De Vleeschouwer, David, e Andrew C. Parnell. "Reducing time-scale uncertainty for the Devonian by integrating astrochronology and Bayesian statistics". Geology 42, n.º 6 (junho de 2014): 491–94. http://dx.doi.org/10.1130/g35618.1.

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14

Hilgen, F. "Integrated stratigraphy and astrochronology of the Messinian GSSP at Oued Akrech (Atlantic Morocco)". Earth and Planetary Science Letters 182, n.º 3-4 (15 de novembro de 2000): 237–51. http://dx.doi.org/10.1016/s0012-821x(00)00247-8.

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15

Li, Mingsong, Chunju Huang, Linda Hinnov, Weizhe Chen, James Ogg e Wei Tian. "Astrochronology of the Anisian stage (Middle Triassic) at the Guandao reference section, South China". Earth and Planetary Science Letters 482 (janeiro de 2018): 591–606. http://dx.doi.org/10.1016/j.epsl.2017.11.042.

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16

Krijgsman, W., A. R. Fortuin, F. J. Hilgen e F. J. Sierro. "Astrochronology for the Messinian Sorbas basin (SE Spain) and orbital (precessional) forcing for evaporite cyclicity". Sedimentary Geology 140, n.º 1-2 (abril de 2001): 43–60. http://dx.doi.org/10.1016/s0037-0738(00)00171-8.

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17

van Assen, E., K. F. Kuiper, N. Barhoun, W. Krijgsman e F. J. Sierro. "Messinian astrochronology of the Melilla Basin: Stepwise restriction of the Mediterranean–Atlantic connection through Morocco". Palaeogeography, Palaeoclimatology, Palaeoecology 238, n.º 1-4 (agosto de 2006): 15–31. http://dx.doi.org/10.1016/j.palaeo.2006.03.014.

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18

Huang, Chunju, Stephen P. Hesselbo e Linda Hinnov. "Astrochronology of the late Jurassic Kimmeridge Clay (Dorset, England) and implications for Earth system processes". Earth and Planetary Science Letters 289, n.º 1-2 (janeiro de 2010): 242–55. http://dx.doi.org/10.1016/j.epsl.2009.11.013.

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19

Lucas, Spencer G., Joerg W. Schneider, Svetlana Nikolaeva e Xiangdong Wang. "The Carboniferous timescale: an introduction". Geological Society, London, Special Publications 512, n.º 1 (14 de dezembro de 2021): 1–17. http://dx.doi.org/10.1144/sp512-2021-160.

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AbstractThe Carboniferous chronostratigraphic scale consists of two subsystems, six series and seven stages. Precise numerical age control within the Carboniferous is uneven, and a global magnetic polarity timescale for the Carboniferous is far from established. Isotope stratigraphy based on Sr, C and O isotopes is at an early stage but has already identified a few Sr and C isotope events of use to global correlation. Cyclostratigraphy has created a workable astrochronology for part of Pennsylvanian time that needs better calibration. Chronostratigraphic definitions of most of the seven Carboniferous stages remain unfinished. Future research on the Carboniferous timescale should focus on Global Stratotype Section and Point (GSSP) selection for the remaining, undefined stage bases, definition and characterization of substages, and further development and integration of the Carboniferous chronostratigraphic scale with radioisotopic, magnetostratigraphic, chemostratigraphic and cyclostratigraphic tools for calibration and correlation, and the cross-correlation of non-marine and marine chronologies.

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20

Malinverno, Alberto, Jordan Hildebrandt, Masako Tominaga e James E. T. Channell. "M-sequence geomagnetic polarity time scale (MHTC12) that steadies global spreading rates and incorporates astrochronology constraints". Journal of Geophysical Research: Solid Earth 117, B6 (junho de 2012): n/a. http://dx.doi.org/10.1029/2012jb009260.

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21

Sahy, Diana, Daniel J. Condon, Frederik J. Hilgen e Klaudia F. Kuiper. "Reducing Disparity in Radio-Isotopic and Astrochronology-Based Time Scales of the Late Eocene and Oligocene". Paleoceanography 32, n.º 10 (outubro de 2017): 1018–35. http://dx.doi.org/10.1002/2017pa003197.

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22

Cheng, Leli, Jian Wang, Youli Wan, Xiugen Fu e Liangxuanzi Zhong. "Astrochronology of the Middle Jurassic Buqu Formation (Tibet, China) and its implications for the Bathonian time scale". Palaeogeography, Palaeoclimatology, Palaeoecology 487 (dezembro de 2017): 51–58. http://dx.doi.org/10.1016/j.palaeo.2017.08.018.

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23

Antonarakou, A., H. Drinia e F. Pomoni-Papaioannou. "THE APPLICATION OF CYCLOSTRATIGRAPHY AND ASTROCHRONOLOGY IN THE NEOGENE MARINE DEPOSITS OF EASTERN MEDITERRANEAN: METOCHIA SECTION (GAVDOS ISLAND)". Bulletin of the Geological Society of Greece 39, n.º 1 (10 de setembro de 2006): 17. http://dx.doi.org/10.12681/bgsg.18443.

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Significant lithostratigraphical and micropaleontological signatures, of Milankovitchscale climatic changes are recorded in Miocene deep-sea sediments. As a case study, the Metochia Section, in Gavdos Island, which covers the time interval from 9.7 to 6.6 Ma, is used. This study emphasizes the sedimentological and micropaleontological characteristics of the section, attributed to Milankovitch-scale climatic changes. The short-term variations in climate and faunal composition are related to precession- controlled sedimentary cycles and the long-term trend in climate is related to eccentricity and obliquity cycles. Regional changes in sea surface temperature in combination with variations of solar insolation have caused the cyclical astronomical controlled pattern of Globorotalia species.

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24

Martinez, Mathieu, Jean-François Deconinck, Pierre Pellenard, Stéphane Reboulet e Laurent Riquier. "Astrochronology of the Valanginian Stage from reference sections (Vocontian Basin, France) and palaeoenvironmental implications for the Weissert Event". Palaeogeography, Palaeoclimatology, Palaeoecology 376 (abril de 2013): 91–102. http://dx.doi.org/10.1016/j.palaeo.2013.02.021.

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25

Huang, Renda, Fujie Jiang, Di Chen, Ruoyuan Qiu, Tao Hu, Linhao Fang, Meiling Hu et al. "Astrochronology and carbon-isotope stratigraphy of the Fengcheng Formation, Junggar Basin: Terrestrial evidence for the Carboniferous-Permian Boundary". Gondwana Research 116 (abril de 2023): 1–11. http://dx.doi.org/10.1016/j.gr.2022.12.016.

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26

Sierro, Francisco J., Santiago Ledesma, José-Abel Flores, Susana Torrescusa e Wenceslao Martínez del Olmo. "Sonic and gamma-ray astrochronology: Cycle to cycle calibration of Atlantic climatic records to Mediterranean sapropels and astronomical oscillations". Geology 28, n.º 8 (agosto de 2000): 695–98. http://dx.doi.org/10.1130/0091-7613(2000)028<0695:sagrac>2.3.co;2.

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27

Sierro, Francisco J., Santiago Ledesma, José-Abel Flores, Susana Torrescusa e Wenceslao Martínez del Olmo. "Sonic and gamma-ray astrochronology: Cycle to cycle calibration of Atlantic climatic records to Mediterranean sapropels and astronomical oscillations". Geology 28, n.º 8 (2000): 695. http://dx.doi.org/10.1130/0091-7613(2000)28<695:sagact>2.0.co;2.

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HENNEBERT, Michel. "The Cretaceous-Paleogene boundary and its 405-kyr eccentricity cycle phase: a new constraint on radiometric dating and astrochronology". Carnets de géologie (Notebooks on geology) 14, n.º 9 (2014): 173–89. http://dx.doi.org/10.4267/2042/53981.

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Vahlenkamp, Maximilian, David De Vleeschouwer, Sietske J. Batenburg, Kirsty M. Edgar, Emma Hanson, Mathieu Martinez, Heiko Pälike et al. "A lower to middle Eocene astrochronology for the Mentelle Basin (Australia) and its implications for the geologic time scale". Earth and Planetary Science Letters 529 (janeiro de 2020): 115865. http://dx.doi.org/10.1016/j.epsl.2019.115865.

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Laurin, Jiří, Stanislav Čech, David Uličný, Zdeněk Štaffen e Marcela Svobodová. "Astrochronology of the Late Turonian: implications for the behavior of the carbon cycle at the demise of peak greenhouse". Earth and Planetary Science Letters 394 (maio de 2014): 254–69. http://dx.doi.org/10.1016/j.epsl.2014.03.023.

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Olsen, Paul E., Dennis V. Kent e Jessica H. Whiteside. "Implications of the Newark Supergroup-based astrochronology and geomagnetic polarity time scale (Newark-APTS) for the tempo and mode of the early diversification of the Dinosauria". Earth and Environmental Science Transactions of the Royal Society of Edinburgh 101, n.º 3-4 (setembro de 2010): 201–29. http://dx.doi.org/10.1017/s1755691011020032.

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ABSTRACTThe Newark-APTS established a high-resolution framework for the Late Triassic and Early Jurassic. Palaeomagnetic polarity correlations to marine sections show that stage-level correlations of continental sequences were off by as much as 10 million years. New U–Pb ages show the new correlations and the Newark basin astrochronology to be accurate. Correlation of Newark-APTS to the Chinle Formation/Dockum Group, Glen Canyon Group, Fleming Fjord Formation and Ischigualasto Formation led to the following conclusions: (1) there are no unequivocal Carnian-age dinosaurs; (2) the Norian Age was characterised by a slowly increasing saurischian diversity but no unequivocal ornithischians; (3) there was profound Norian and Rhaetian continental provinciality; (4) the classic Chinle-, Germanic- and Los Colorados-type assemblages may have persisted to the close of the Rhaetian; (5) the distinct genus-level biotic transition traditionally correlated with the marine Carnian–Norian is in fact mid-Norian in age and within published error of the Manicouagan impact; (6) the end-Triassic marine and continental extinctions as seen in eastern North America were contemporaneous; and (7) compared to Triassic communities, Hettangian and Sinemurian age terrestrial communities were nearly globally homogenous and of low diversity. Consequently, the complex emerging picture of dinosaur diversification demands biostratigraphically-independent geochronologies in each of the faunally-important regions.

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Montañez, Isabel Patricia. "Current synthesis of the penultimate icehouse and its imprint on the Upper Devonian through Permian stratigraphic record". Geological Society, London, Special Publications 512, n.º 1 (29 de setembro de 2021): 213–45. http://dx.doi.org/10.1144/sp512-2021-124.

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AbstractIcehouses are the less common climate state on Earth, and thus it is notable that the longest-lived (c.370 to 260 Ma) and possibly most extensive and intense of icehouse periods spanned the Carboniferous Period. Mid- to high-latitude glaciogenic deposits reveal a dynamic glaciation–deglaciation history with ice waxing and waning from multiple ice centres and possible transcontinental ice sheets during the apex of glaciation. New high-precision U–Pb ages confirm a hypothesized west-to-east progression of glaciation through the icehouse, but reveal that its demise occurred as a series of synchronous and widespread deglaciations. The dynamic glaciation history, along with repeated perturbations to Earth System components, are archived in the low-latitude stratigraphic record, revealing similarities to the Cenozoic icehouse. Further assessing the phasing between climate, oceanographic, and biotic changes during the icehouse requires additional chronostratigraphic constraints. Astrochronology permits the deciphering of time, at high resolution, in the late Paleozoic record as has been demonstrated in deep- and quiet-water deposits. Rigorous testing for astronomical forcing in low-latitude cyclothemic successions, which have a direct link to higher-latitude glaciogenic records through inferred glacioeustasy, however, will require a comprehensive approach that integrates new techniques with further optimization and additional independent age constraints given challenges associated with shallow-marine to terrestrial records.

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33

Jin, Siding, Sibing Liu, Zheng Li, Anqing Chen e Chao Ma. "Astrochronology of a middle Eocene lacustrine sequence and sedimentary noise modeling of lake-level changes in Dongying Depression, Bohai Bay Basin". Palaeogeography, Palaeoclimatology, Palaeoecology 585 (janeiro de 2022): 110740. http://dx.doi.org/10.1016/j.palaeo.2021.110740.

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Sabatino, Nadia, Stephen R. Meyers, Silke Voigt, Rodolfo Coccioni e Mario Sprovieri. "A new high-resolution carbon-isotope stratigraphy for the Campanian (Bottaccione section): Its implications for global correlation, ocean circulation, and astrochronology". Palaeogeography, Palaeoclimatology, Palaeoecology 489 (janeiro de 2018): 29–39. http://dx.doi.org/10.1016/j.palaeo.2017.08.026.

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Galeotti, Simone, Diana Sahy, Claudia Agnini, Daniel Condon, Eliana Fornaciari, Federica Francescone, Luca Giusberti, Heiko Pälike, David J. A. Spofforth e Domenico Rio. "Astrochronology and radio-isotopic dating of the Alano di Piave section (NE Italy), candidate GSSP for the Priabonian Stage (late Eocene)". Earth and Planetary Science Letters 525 (novembro de 2019): 115746. http://dx.doi.org/10.1016/j.epsl.2019.115746.

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Machlus, Malka L., Jahandar Ramezani, Samuel A. Bowring, Sidney R. Hemming, Kaori Tsukui e William C. Clyde. "A strategy for cross-calibrating U–Pb chronology and astrochronology of sedimentary sequences: An example from the Green River Formation, Wyoming, USA". Earth and Planetary Science Letters 413 (março de 2015): 70–78. http://dx.doi.org/10.1016/j.epsl.2014.12.009.

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Yao, Xu, Shuang Dai, Mingsong Li e Linda Hinnov. "Orbital eccentricity and inclination metronomes in Middle Miocene lacustrine mudstones of Jiuxi Basin, Tibet: Closing an astrochronology time gap and calibrating global cooling events". Global and Planetary Change 215 (agosto de 2022): 103896. http://dx.doi.org/10.1016/j.gloplacha.2022.103896.

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Martinez, Mathieu, Jean-François Deconinck, Pierre Pellenard, Laurent Riquier, Miguel Company, Stéphane Reboulet e Mathieu Moiroud. "Astrochronology of the Valanginian–Hauterivian stages (Early Cretaceous): Chronological relationships between the Paraná–Etendeka large igneous province and the Weissert and the Faraoni events". Global and Planetary Change 131 (agosto de 2015): 158–73. http://dx.doi.org/10.1016/j.gloplacha.2015.06.001.

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Westerhold, Thomas, Ursula Röhl, Roy H. Wilkens, Philip D. Gingerich, William C. Clyde, Scott L. Wing, Gabriel J. Bowen e Mary J. Kraus. "Synchronizing early Eocene deep-sea and continental records – cyclostratigraphic age models for the Bighorn Basin Coring Project drill cores". Climate of the Past 14, n.º 3 (8 de março de 2018): 303–19. http://dx.doi.org/10.5194/cp-14-303-2018.

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Abstract. A consistent chronostratigraphic framework is required to understand the effect of major paleoclimate perturbations on both marine and terrestrial ecosystems. Transient global warming events in the early Eocene, at 56–54 Ma, show the impact of large-scale carbon input into the ocean–atmosphere system. Here we provide the first timescale synchronization of continental and marine deposits spanning the Paleocene–Eocene Thermal Maximum (PETM) and the interval just prior to the Eocene Thermal Maximum 2 (ETM-2). Cyclic variations in geochemical data come from continental drill cores of the Bighorn Basin Coring Project (BBCP, Wyoming, USA) and from marine deep-sea drilling deposits retrieved by the Ocean Drilling Program (ODP). Both are dominated by eccentricity-modulated precession cycles used to construct a common cyclostratigraphic framework. Integration of age models results in a revised astrochronology for the PETM in deep-sea records that is now generally consistent with independent 3He age models. The duration of the PETM is estimated at ∼ 200 kyr for the carbon isotope excursion and ∼ 120 kyr for the associated pelagic clay layer. A common terrestrial and marine age model shows a concurrent major change in marine and terrestrial biota ∼ 200 kyr before ETM-2. In the Bighorn Basin, the change is referred to as Biohorizon B and represents a period of significant mammalian turnover and immigration, separating the upper Haplomylus–Ectocion Range Zone from the Bunophorus Interval Zone and approximating the Wa-4–Wa-5 land mammal zone boundary. In sediments from ODP Site 1262 (Walvis Ridge), major changes in the biota at this time are documented by the radiation of a “second generation” of apical spine-bearing sphenolith species (e.g., S. radians and S. editus), the emergence of T. orthostylus, and the marked decline of D. multiradiatus.

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Sun, Zhongheng, Tao Jiang, Hongtao Zhu, Xinluo Feng e Pengli Wei. "Reconstruction of Lake-Level Changes by Sedimentary Noise Modeling (Dongying Depression, Late Eocene, East China)". Energies 16, n.º 5 (24 de fevereiro de 2023): 2216. http://dx.doi.org/10.3390/en16052216.

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The late Eocene succession of the Dongying Depression forms a highly productive hydrocarbon source. However, due to lack of an unambiguous fine chronostratigraphic framework for the late Eocene stratigraphy, it is challenging to understand the paleolake’s evolution and the driven mechanism of lake-level variation, a limitation which hinders hydrocarbon exploration. In this work, high-resolution gamma-ray logging data were analyzed to carry out the cyclostratigraphic analysis of the third member (Es3) of the Shahejie Formation in the Dongying Depression. Significant 405-kyr eccentricity cycles were recognized based on time series analysis and statistical modeling of estimated sedimentation rates. We abstracted ~57 m cycles of the GR data in the Es3 member, which were comparable with the long eccentricity cycles (~405-kyr) of the La2004 astronomical solution, yielding a 6.43 Myr long astronomical time scale (ATS) for the whole Es3 member. The calibrated astronomical age of the third/fourth member of the Shahejie Formation boundary (41.21 Ma) was adopted as an anchor point for tuning our astrochronology, which provided an absolute ATS ranging from 34.78 ± 0.42 Ma to 41.21 ± 0.42 Ma in Es3. According to the ATS, sedimentary noise modeling for the reconstruction of lake-level changes was performed through the late Eocene Es3. The lake-level changes obtained based on sedimentary noise modeling and spectrum analysis reveal significant ~1.2 Myr cycles consistent with global sea level variations which were related to astronomical forcing. Potential driven mechanisms of marine incursion and/or groundwater table modulation were linked to explain the co-variation of global sea level changes and regional lake level changes. Our results suggest global sea level fluctuations may have played an important role in driving the hydroclimate and paleolake evolution of the late Eocene Dongying Depression.

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Wu, Huaichun, Shihong Zhang, Ganqing Jiang, Linda Hinnov, Tianshui Yang, Haiyan Li, Xiaoqiao Wan e Chengshan Wang. "Astrochronology of the Early Turonian–Early Campanian terrestrial succession in the Songliao Basin, northeastern China and its implication for long-period behavior of the Solar System". Palaeogeography, Palaeoclimatology, Palaeoecology 385 (setembro de 2013): 55–70. http://dx.doi.org/10.1016/j.palaeo.2012.09.004.

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Pas, Damien, Anne-Christine Da Silva, D. Jeffrey Over, Carlton E. Brett, Lauren Brandt, Jin-Si Over, Frederik J. Hilgen e Mark J. Dekkers. "Cyclostratigraphic calibration of the Eifelian Stage (Middle Devonian, Appalachian Basin, Western New York, USA)". GSA Bulletin 133, n.º 1-2 (9 de junho de 2020): 277–86. http://dx.doi.org/10.1130/b35589.1.

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Abstract Over the past decade the integration of astrochronology and U/Pb thermal ionization mass spectrometry dating has resulted in major improvements in the Devonian time scale, which allowed for accurate determination of ages and rates of change in this critical interval of Earth history. However, widely different durations have been published for the Middle Devonian Eifelian stage. Here we aim to solve this discrepancy by building an astronomically calibrated time scale using a high-resolution geochemical data set collected in the early to late Eifelian outer-ramp and deep-shelf deposits of the Seneca section (Appalachian Basin, Western New York, USA). The Middle Devonian Eifelian Stage (GTS2012; base at 393.3 ± 1.2 m.y. and duration estimate of 5.6 ± 1.9 m.y.), is bracketed by two major bioevents, respectively the Choteč event at its base and the Kačák event just prior to the Eifelian–Givetian boundary. To capture the record of Milankovitch-scale climatic cycles and to develop a model of the climatic and oceanographic variations that affected the Appalachian Basin during the Eifelian, 750 samples were collected at typically 2.5 cm intervals across the Seneca section. Major and trace elements were measured on each sample with an inductively coupled plasma–optical emission spectrometer. To estimate the duration of the Seneca section sampled, we applied multiple spectral techniques such as harmonic analysis, the multi-taper, and evolutionary spectral analysis, and we tuned the Log10Ti series using the short orbital eccentricity ∼100 k.y. cycle. Then, to assess the reliability of our cyclostratigraphic interpretation we ran the Average Spectral Misfit method on selected proxies for detrital input variation. The estimated duration derived using this method falls in the range of durations estimated with the tuning method. Using the approximate position of the Emsian–Eifelian and Eifelian–Givetian boundaries, constrained within <1 m, the proposed estimation of the total duration of the Eifelian age is ∼5 m.y. Interpolated from the high-resolution U-Pb radiometric age available for the Tioga F Bentonite, the numerical ages of the Emsian–Eifelian and the Eifelian–Givetian were respectively recalibrated at 393.39 Ma and 388.24 Ma. The uncertainty from the radiometric date is respectively ± 0.86 Ma and ± 0.86 Ma.

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Westerhold, Thomas, Ursula Röhl, Thomas Frederichs, Claudia Agnini, Isabella Raffi, James C. Zachos e Roy H. Wilkens. "Astronomical calibration of the Ypresian timescale: implications for seafloor spreading rates and the chaotic behavior of the solar system?" Climate of the Past 13, n.º 9 (11 de setembro de 2017): 1129–52. http://dx.doi.org/10.5194/cp-13-1129-2017.

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Abstract. To fully understand the global climate dynamics of the warm early Eocene with its reoccurring hyperthermal events, an accurate high-fidelity age model is required. The Ypresian stage (56–47.8 Ma) covers a key interval within the Eocene as it ranges from the warmest marine temperatures in the early Eocene to the long-term cooling trends in the middle Eocene. Despite the recent development of detailed marine isotope records spanning portions of the Ypresian stage, key records to establish a complete astronomically calibrated age model for the Ypresian are still missing. Here we present new high-resolution X-ray fluorescence (XRF) core scanning iron intensity, bulk stable isotope, calcareous nannofossil, and magnetostratigraphic data generated on core material from ODP Sites 1258 (Leg 207, Demerara Rise), 1262, 1263, 1265, and 1267 (Leg 208, Walvis Ridge) recovered in the equatorial and South Atlantic Ocean. By combining new data with published records, a 405 kyr eccentricity cyclostratigraphic framework was established, revealing a 300–400 kyr long condensed interval for magnetochron C22n in the Leg 208 succession. Because the amplitudes are dominated by eccentricity, the XRF data help to identify the most suitable orbital solution for astronomical tuning of the Ypresian. Our new records fit best with the La2010b numerical solution for eccentricity, which was used as a target curve for compiling the Ypresian astronomical timescale (YATS). The consistent positions of the very long eccentricity minima in the geological data and the La2010b solution suggest that the macroscopic feature displaying the chaotic diffusion of the planetary orbits, the transition from libration to circulation in the combination of angles in the precession motion of the orbits of Earth and Mars, occurred ∼ 52 Ma. This adds to the geological evidence for the chaotic behavior of the solar system. Additionally, the new astrochronology and revised magnetostratigraphy provide robust ages and durations for Chrons C21n to C24n (47–54 Ma), revealing a major change in spreading rates in the interval from 51.0 to 52.5 Ma. This major change in spreading rates is synchronous with a global reorganization of the plate–mantle system and the chaotic diffusion of the planetary orbits. The newly provided YATS also includes new absolute ages for biostratigraphic events, magnetic polarity reversals, and early Eocene hyperthermal events. Our new bio- and magnetostratigraphically calibrated stable isotope compilation may act as a reference for further paleoclimate studies of the Ypresian, which is of special interest because of the outgoing warming and increasingly cooling phase. Finally, our approach of integrating the complex comprehensive data sets unearths some challenges and uncertainties but also validates the high potential of chemostratigraphy, magnetostratigraphy, and biostratigraphy in unprecedented detail being most significant for an accurate chronostratigraphy.

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Meyers, Stephen R. "Cyclostratigraphy and the problem of astrochronologic testing". Earth-Science Reviews 190 (março de 2019): 190–223. http://dx.doi.org/10.1016/j.earscirev.2018.11.015.

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Mitchell, Ross N., Uwe Kirscher, Marcus Kunzmann, Yebo Liu e Grant M. Cox. "Gulf of Nuna: Astrochronologic correlation of a Mesoproterozoic oceanic euxinic event". Geology 49, n.º 1 (25 de agosto de 2020): 25–29. http://dx.doi.org/10.1130/g47587.1.

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Abstract The ca. 1.4 Ga Velkerri and Xiamaling Formations, in Australia and the north China craton, respectively, are both carbonaceous shale deposits that record a prominent euxinic interval and were intruded by ca. 1.3 Ga dolerite sills. These similarities raise the possibility that these two units correlate, which would suggest the occurrence of widespread euxinia, organic carbon burial, and source rock deposition. Paleomagnetic data are consistent with Australia and the north China craton being neighbors in the supercontinent Nuna and thus permit deposition in a single large basin, and the putative stratigraphic correlation. However, lack of geochronological data has precluded definitive testing. The Xiamaling Formation has been shown to exhibit depositional control by orbital cycles. Here, we tested the putative correlation with the Velkerri Formation by cyclostratigraphic analysis. The Velkerri Formation exhibits sedimentological cycles that can be interpreted to represent the entire hierarchy of orbital cycles, according to a sedimentation rate that is consistent with Re-Os ages. Comparison of the inferred durations of the euxinic intervals preserved in both the Xiamaling and Velkerri Formations reveals a nearly identical ∼10-m.y.-long oceanic euxinic event. This permits the interpretation that the two hydrocarbon-rich units were deposited and matured in the same basin of Nuna, similar to the Gulf of Mexico during the breakup of Pangea.

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Dermitzakis, M. D. "THE STATUS OF STRATIGRAPHY IN THE 21ST CENTURY". Bulletin of the Geological Society of Greece 43, n.º 1 (19 de janeiro de 2017): 86. http://dx.doi.org/10.12681/bgsg.11162.

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The 21st century geological time scale (GTS) will comprise an internationally agreed chronologic hierarchy. Correlation of events into the GTS will be undertaken using a wide variety of methods, including numeric dating, fossil occurrence, physical and chemical properties, tephrochronology and astrochronologic retrodictions. Chronostratigraphic subdivision of the sedimentary rock record should proceed in a bottom up hierarchical manner with lower units defining the boundaries of stratigraphically higher units. A moderate amount of work is required to improve the basis of the hierarchical subdivision of some Cenozoic series boundary subdivisions and to bring them in line with recommendations by the Stratigraphic Guide and recommendations by the International Committee of Stratigraphy (ICS).

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Li, Haiyan, Shihong Zhang, Jian Han, Tao Zhong, Jikai Ding, Huaichun Wu, Pengju Liu et al. "Astrochronologic calibration of the Shuram carbon isotope excursion with new data from South China". Global and Planetary Change 209 (fevereiro de 2022): 103749. http://dx.doi.org/10.1016/j.gloplacha.2022.103749.

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Ponomareva, Vera, Natalia Bubenshchikova, Maxim Portnyagin, Egor Zelenin, Alexander Derkachev, Sergey Gorbarenko, Dieter Garbe-Schönberg e Ilya Bindeman. "Large-magnitude Pauzhetka caldera-forming eruption in Kamchatka: Astrochronologic age, composition and tephra dispersal". Journal of Volcanology and Geothermal Research 366 (outubro de 2018): 1–12. http://dx.doi.org/10.1016/j.jvolgeores.2018.10.006.

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Ma, Chao, Stephen R. Meyers e Bradley B. Sageman. "Testing Late Cretaceous astronomical solutions in a 15 million year astrochronologic record from North America". Earth and Planetary Science Letters 513 (maio de 2019): 1–11. http://dx.doi.org/10.1016/j.epsl.2019.01.053.

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Meyers, Stephen R., Sarah E. Siewert, Brad S. Singer, Bradley B. Sageman, Daniel J. Condon, John D. Obradovich, Brian R. Jicha e David A. Sawyer. "Intercalibration of radioisotopic and astrochronologic time scales for the Cenomanian-Turonian boundary interval, Western Interior Basin, USA". Geology 40, n.º 1 (janeiro de 2012): 7–10. http://dx.doi.org/10.1130/g32261.1.

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