Hf isotopic evidence for Paleoarchean (> 3.5 Ga) crustal components in the Korean Peninsula

다국어 초록 (Multilingual Abstract)

We report in-situ Hf isotopic data on five inherited zircon components, dated at >3.0Ga from previous Sensitive High Resolution Ion Microprobe (SHRIMP) U-Pb analyses. These data are useful for constraining the timing and nature of very pristine crustal materials in South Korea. 176Hf/177Hf isotope ratios, measured using a laser ablation Multi-collector Induced Coupled Plasma Mass Spectrometer (MC-ICP MS), range from 0.28044 to 0.28075, corresponding to the present-day Hf(0) of 70 to 81. They yield two-stage Hf model ages of ca. 4.1 to 3.5 Ga at the time of zircon crystallization from a magma, depending on tenable crustal evolution models. Our results provide the first Hf isotopic evidence for existence of Paleoarchean (>3.5 Ga) crustal components in the Korean Peninsula.

참고문헌 (Reference)

1 "^Manuscript accepted" 2007.12.5

2 Rubatto, D, "Zircon trace element geochemistry: partitioning with garnet and link between U-Pb ages and metamorphism" 184 : 123138-, 2002

3 Griffin, W.L, "Zircon chemistry and magma genesis, SE China: in-situ analysis of Hf isotopes, Tonglu and Pingtan Igneous Complexes" 61 : 237269-61, 2002

4 "Zircon Hf-isotope analysis with an excimer laser ablation of complex geometries" 209 : 121135-, 2004

5 Rubatto, D., "Use of cathodoluminescence for U-Pb zircon dating by ion microprobe: Some examples from the Western Alps" Springer-Verlag, Heidelberg 373400-, 2000

6 Griffin, W.L, "The Hf isotope composition of cratonic mantle LAM-MC-ICPMS analysis of zircon megacrysts in kimberlites" 64 : 133147-, 2000

7 Sderlund U, "The 176Lu decay constant determined by Lu-Hf and U-Pb isotope systematics of Precambrian mafic intrusions" 219 : 311324-, 2004

8 Blichert-Toft J, "Sm-147-Nd-143 and Lu-176-Hf-176 in eucrites and the differentiation of the HED parent body" 204 : 167-181, 2002

9 "Separation of Hf and Lu for high-precision isotope analysis of rock samples by magnetic sector-multiple collector ICPMS" 127 : 248260-, 1997

10 Cho, D.-L, "SHRIMP U-Pb zircon geochronology of biotite- and leucocratic gneisses in Pocheon area Constraints on timing of sedimentation and regional metamorphism" Gwangju 76-, 2003

11 Faure, "Principles of Isotope Geology" John Wiley and Sons 589-, 1986

12 Cheong, C.-S, "Pb and Nd isotopic constraints on Paleoproterozoic crustal evolution of the northeastern Yeongnam massif South Korea" 102 : 207220-, 2000

13 Sagong, H., Cheong, C.-S., "Paleoproterozoic orogeny in South Korea evidence from SmNd and Pb stepleaching garnet ages of Precambrian basement rocks" 122 : 275295-, 2003

14 Lan, C.-Y, "Nd isotopic study of Precambrian basement of South Korea evidence for Early Archean crust" 23 : 249252-, 1995

15 Amelin, Y, "Nature of the Earths earliest crust from hafnium isotopes in single detrital zircons" 399 : 252255-, 1999

16 "Metamorphic effect on zircon LuHf and UPb isotope systems in ultrahigh-pressure eclogite-facies metagranite and metabasite" 240 : 378400-, 2005

17 "Manuscript received" 2007.8

18 Patchett P, "Lu-Hf total-rock isochron for the eucrite meteorites" 1980

19 Patchett P. J, "Lu-Hf and Sm-Nd isotopic systematics in chondrites and their constraints on the Lu-Hf properties of the earth" 222 : 2941-, 2004

20 Vervoort, J.D, "Isotopic composition of Yb and the determination of Lu concentrations and Lu/Hf ratios by isotopic dilution using MC-ICPMS" 2004

21 Nebel, O, "Initial Hf isotope compositions in magmatic zircon from early Proterozoic rocks from the Gawler Craton A test for zircon model ages" 241 : 2337-, 2007

22 Iizuka, T, "Improvements of precision and accuracy in in-situ Hf isotope microanalysis of zircon using the laser ablation-MC-ICPMS technique" 220 : 121137-, 2005

23 "Implications based on the first SHRIMP UPb zircon dating on Precambrian granitoid rocks in North Korea" 251 : 365379-, 2006

24 Nowell, G.M, "High precision Hf isotope measurements of MORB and OIB by thermal ionisation mass spectrometry insights into the depleted mantle" 149 : 211233-, 1998

25 "Hf isotopic compositions of the standard zircons for UPb dating" 49 : 16421648-, 2004

26 "Hf isotopic compositions of the standard zircons and baddeleyites used in UPb geochronology" 234 : 105126-, 2006

27 Chu, N.C, "Hf isotope ratio analysis using multi-collector inductively coupled plasma mass spectrometry: an evaluation of isobaric interference corrections" 17 : 15671574-, 2002

28 Lee, "Geology of Korea" 514-, 1987

29 Amelin, Y, "Geochronology of the Jack Hills detrital zircons by precise UPb isotope dilution analysis of crystal fragments" 146 : 2538-, 1998

30 "Geochemical test for branching decay of 176Lu" 69 : 465473-, 2005

31 "Early history of Earths crust-mantle system inferred from hafnium isotopes in chondrites" 421 : 931933-, 2003

32 Jeon, H, "Early Archean to Middle Jurassic evolution of the Korean Peninsula and its correlation with Chinese Cratons : SHRIMP U-Pb zircon age constraints" 115 : 525539-, 2007

33 "Detrital zircon U-Pb and Hf isotopic constrains on the crustal evolution of North Korea" 159 : 155177-, 2007

34 Lee, S.R, "Crustal evolution of the Gyeonggi massif Nd isotopic evidence and implications for continental growths of East Asia" 121 : 2534-, 2003

35 Scherer, E, "Calibration of the lutetiumhafnium clock" 293 : 683687-, 2001

36 Vervoort, J.D, "Behavior of hafnium and neodymium isotopes in the crust constraints from Precambrian crustally derived granites" 60 : 337173733-, 1996