Detrital Zircon Age Structure Within Ca. 3Ga
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Eoarchean Crustal Evolution of the Jack Hills Zircon Source and Loss of Hadean Crust
Available online at www.sciencedirect.com ScienceDirect Geochimica et Cosmochimica Acta 146 (2014) 27–42 www.elsevier.com/locate/gca Eoarchean crustal evolution of the Jack Hills zircon source and loss of Hadean crust Elizabeth A. Bell ⇑, T. Mark Harrison, Issaku E. Kohl, Edward D. Young Dept. of Earth, Planetary, and Space Sciences, UCLA, United States Received 10 March 2014; accepted in revised form 18 September 2014; available online 30 September 2014 Abstract Given the global dearth of Hadean (>4 Ga) rocks, 4.4–4.0 Ga detrital zircons from Jack Hills, Narryer Gneiss Complex (Yilgarn Craton, Western Australia) constitute our best archive of early terrestrial materials. Previous Lu–Hf investigations of these zircons suggested that felsic (low Lu/Hf) crust formation began by 4.4 to 4.5 Ga and continued for several hundred million years with evidence of the least radiogenic Hf component persisting until at least 4 Ga. However, evidence for the involvement of Hadean materials in later crustal evolution is sparse, and even in the detrital Jack Hills zircon population, the most unradiogenic, ancient isotopic signals have not been definitively identified in the younger (<3.9 Ga) rock and zircon record. Here we show Lu–Hf data from <4 Ga Jack Hills detrital zircons that document a significant and previously unknown transition in Yilgarn Craton crustal evolution between 3.9 and 3.7 Ga. The zircon source region evolved largely by internal reworking through the period 4.0–3.8 Ga, and the most ancient and unradiogenic components of the crust are mostly missing from the record after 4 Ga. -
Earth's Oldest Rocks
Chapter 12 The Oldest Terrestrial Mineral Record: Thirty Years of Research on Hadean Zircon From Jack Hills, Western Australia Aaron J. Cavosie1, John W. Valley2 and Simon A. Wilde3 1Curtin University, Perth, WA, Australia; 2University of WisconsineMadison, Madison, WI, United States; 3Curtin University of Technology, Perth, WA, Australia Chapter Outline 1. Introduction 255 3.4.1 Lithium 266 2. Jack Hills Metasedimentary Rocks 256 3.4.2 Ti Thermometry 266 2.1 Age of Deposition 257 3.4.3 Rare Earth Elements, Yttrium and Phosphorous 266 2.2 Metamorphism 258 3.4.4 Other Trace Elements (Al, Sc, Sm/Nd, Xe) 267 2.3 Geology of Adjacent Rocks 258 3.5 Hafnium Isotopic Compositions 267 3. Studies of Jack Hills Zircon 259 3.6 Mineral Inclusion Studies 268 3.1 Images of Jack Hills Zircon 259 4. Early Earth Processes Recorded by Jack Hills Zircon 270 3.2 Age of the Hadean Zircon Population 259 4.1 Derivation of Jack Hills Zircon From Early Mafic 3.2.1 The UePb Story 259 Crust (εHf) 270 3.2.2 U Abundance, Radiation Damage, and Pb Loss 261 4.2 Existence of >4300 Ma Granitoid 270 3.2.3 The Oldest Grains in the Jack Hills 262 4.3 Significance of Surface Alteration on the Early Earth 271 3.2.4 Distribution of Hadean Grains 264 4.4 Impact Events Recorded in Jack Hills Zircon? 271 3.3 Oxygen Isotopes 264 Acknowledgments 273 3.4 Trace Elements 266 References 273 1. INTRODUCTION Little is known of the early Earth because of the absence of a rock record for the first 500 million years after accretion. -
Paleomagnetism Indicates That Primary Magnetite in Zircon Records
Paleomagnetism indicates that primary magnetite in zircon records a strong Hadean geodynamo John A. Tardunoa,b,1 , Rory D. Cottrella , Richard K. Bonoa,2 , Hirokuni Odac , William J. Davisd , Mostafa Fayeke , Olaf van ’t Ervef , Francis Nimmog , Wentao Huanga , Eric R. Thernh,i , Sebastian Fearnj , Gautam Mitraa, Aleksey V. Smirnovk , and Eric G. Blackmanb aDepartment of Earth and Environmental Sciences, University of Rochester, Rochester, NY 14627; bDepartment of Physics and Astronomy, University of Rochester, Rochester, NY 14627; cResearch Institute of Geology and Geoinformation, Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8567, Japan; dGeological Survey of Canada, GSC-Central Canada, Geochronology, Ottawa, ON K1A 0E8, Canada; eDepartment of Geological Sciences, University of Manitoba, Winnipeg, MB R3T 2N2, Canada; fMaterials Science and Technology Division, Naval Research Laboratory, Washington, DC 20375; gDepartment of Earth and Planetary Sciences, University of California, Santa Cruz, CA 95064; hGeochron Research Group, Bentley, WA 6982, Australia; iDepartment of Applied Physics, Curtin University of Technology, Perth, WA 6001, Australia; jDepartment of Geoscience, University of Wisconsin–Milwaukee, Milwaukee, WI 53201-0413; and kDepartment of Geological and Mining Engineering and Sciences, Michigan Technological University, Houghton, MI 49931 Edited by Lisa Tauxe, University of California San Diego, La Jolla, CA, and approved December 12, 2019 (received for review September 24, 2019) Determining the age of the geomagnetic field is of paramount tion on the billion-year timescales needed to explore the most importance for understanding the evolution of the planet because ancient geodynamo. Here we use “single-domain–like” in a the field shields the atmosphere from erosion by the solar wind. -
Pervasive Remagnetization of Detrital Zircon Host Rocks in the Jack Hills, Western Australia and Implications for Records of the Early Geodynamo ∗ Benjamin P
Earth and Planetary Science Letters 430 (2015) 115–128 Contents lists available at ScienceDirect Earth and Planetary Science Letters www.elsevier.com/locate/epsl Pervasive remagnetization of detrital zircon host rocks in the Jack Hills, Western Australia and implications for records of the early geodynamo ∗ Benjamin P. Weiss a,b, , Adam C. Maloof c, Nicholas Tailby d,e, Jahandar Ramezani a, Roger R. Fu a, Veronica Hanus a, Dustin Trail f, E. Bruce Watson d,e, T. Mark Harrison g, Samuel A. Bowring a, Joseph L. Kirschvink h,i, Nicholas L. Swanson-Hysell b, Robert S. Coe j a Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA b Department of Earth and Planetary Science, University of California (UC), Berkeley, Berkeley, CA 94720, USA c Department of Geosciences, Princeton University, Guyot Hall, Washington Road, Princeton, NJ 08544, USA d Department of Earth and Environmental Sciences, Rensselaer Polytechnic Institute, Troy, NY 12180, USA e New York Center for Astrobiology, Rensselaer Polytechnic Institute, Troy, NY 12180, USA f Department of Earth and Environmental Sciences, Box 270221, University of Rochester, Rochester, NY 14627, USA g Institute of Geophysics and Planetary Physics, UC, Los Angeles, Los Angeles, CA 90095, USA h Division of Geological and Planetary Sciences, California Institute of Technology, USA i Earth-Life Science Institute, Tokyo Institute of Technology, Meguro, Tokyo, Japan j Department of Earth and Planetary Sciences, UC, Santa Cruz, CA 95064, USA a r t i c l e i n f o a b s t r a c t Article history: It currently is unknown when Earth’s dynamo magnetic field originated.