Hadean–Archean Detrital Zircons from Jatulian Quartzites ... - Springer

ISSN 1028-334X, Doklady Earth Sciences, 2010, Vol. 431, Part 1, pp. 318–323. © Pleiades Publishing, Ltd., 2010.Original Russian Text © V.N. Kozhevnikov, S.G. Skublov, Yu.B. Marin, P.V. Medvedev, Yu. Systra, V. Valencia, 2010, published in Doklady Akademii Nauk, 2010, Vol. 431, No. 1,pp. 85–90.GEOCHEMISTRYHadean–Archean Detrital Zircons from Jatulian Quartzitesand Conglomerates of the Karelian CratonV. N. Kozhevnikov a , S. G. Skublov b , Corresponding Member of the RAS Yu. B. Marin c ,P. V. Medvedev a , Yu. Systra d , and V. Valencia eReceived October 1, 2009Abstract—Using local procedures, the new results on the isotope ages and composition of mineral inclusionswere obtained for detrital zircons from Paleoproterozoic Jatulian terrigenous quartzites and polymictic conglomeratesin Central and Western Karelia. For Eastern Laurasia, signs of the existence of Hadean andancient Eoarchean matter were found for the first time (zircon grains of 3871 ± 38.6 and 3837 ± 42.1 Ma concordantages). The multimodal distribution of ages within 3.45–2.61 Ga was revealed. The discovery of theoldest zircon grains provides the conditions for valid global correlations of geological events that determinedthe deposition and formation of the continental crust of the North Atlantic supercraton.DOI: 10.1134/S1028334X10030128Zircon is one of the most universal geochronometerminerals. Its high strength and chemical resistancewithin a wide range of P–T conditions determine itsoccurrence as detritals grains in terrigenous atmoclasticrocks (conglomerates, arcozes, etc.). The specificrole of zircons as such was revealed in the course of thereconstruction of the earliest (>3.85 Ga) Hadean processesof the continental crust formation and transformation.The Earth’s oldest detrital zircons (to 4.4 Ga)also constituting the most ancient substance of terrestrialorigin were first found in the Jack Hills area of theYilgara craton in Western Australia [1].Up to now, Hadean detrital zircons have been discoveredin conglomerates and quartzites from severalEarly Precambrian cratons: the North Atlantic supercratonin West Greenland (the Isua belt [2] and theAquilia formation [3]), at the Yellowknife supergroupbasis in Slave [4], in Wyoming [5], and on the LabradorPeninsula [6], in the Sino-Korean craton in HebeiProvince [7], and in the central zone of the Limpopobelt in South Africa [8]. Thus, the number of the terrestrialsites where detrital zircons of Hadean age havebeen found is estimated in the single digits, and thisage group constitutes below 1% all the zircon populationsin rock samples, amounting up to 6% in specialaInstitute of Geology, Karelian Scientific Center,Russian Academy of Sciences, Petrozavodsk, RussiabInstitute of Geology and Geochronology,Russian Academy of Sciences, St. Petersburg, RussiacPlekhanov St. Petersburg Mining Institute,St. Petersburg, RussiadTallinn Technological University, Tallinn, EstoniaeUniversity of Arizona, Tucson, USAemail: kvn04@sampo.rucases [9]. The exclusive role of Hadean-age detritalzircons as carriers of information on the first hundredMa of the Earth’s history makes each discovery ofthem in new regions a subject of great interest forresearchers.This report presents the results of isotope studies ofdetrital zircons from Paleoproterozoic quartzites andconglomerates of the Karelian craton (Fig. 1).Numerous populations of these zircons include singlegrains of Hadean and Eoarchean age (by now, the oldestones for both the Fennoscandian shield and theterritory of Eurasia). Until now, for the Fenoscandianshield, the oldest ages of detrital zircons were obtainedfor the gneisses of the Kola series of the Central Kolablock (about 3.6 Ga) [10], Proterozoic sediments inthe belts of Tampere in Finland and Vestervik in CentralSweden (3.33–3.44 Ga) [11], and quartzites fromthe Late Archean Matkalahti belt in South Karelia(3.34 Ga) [12]. The oldest dates were determined inthe grain of xenogenic zircon from Siurua trondemitegneisses in Eastern Finland (3.73 Ga [13]), and forsingle atmoclastic zircons from Early Precambrianmetasediments of the Lapland–Kolvitsa belt (3.67 Ga[14]). The authors dealt with detrital zircons from terrigenousclastic rocks in Jatulian sections of theVoloma syncline in Western Karelia and in the westernpart of the Onega syncline (Fig. 1).The sample S-3976 of Jatulian quartzitic sandstonesof about 3 kg mass from which zircons were isolatedwas obtained at the eastern limb of the Volomasyncline. The terrigenous deposits of the Jatuliansuperlayer of the age range estimated as 2.3–2.1 Ga,with angular discordance, underlying rock erosion,and weathering crusts at the basis, occur at Archeangranitoids, granitic gneisses and greenstone Lopianrocks, at Paleoproterozoic volcanites (Sumian318

HADEAN–ARCHEAN DETRITAL ZIRCONS 319LakeLakeLake12345678910111213141516WHITE SEALakeS-3976Lake5883LakeOnegaLakeLakeLadoga0 25 kmFig. 1. Geological scheme of Karelia and the location of testing sites: (1) Paleozoic cover; (2–7) Vendian (2), Riphean (3, includingrapakivi granites), Vepsian (4), Kalevian (5), Jatulian (6), and Sumian–Sariolian (7) Paleoproterozoic deposits; (8–10)Archean greenstone vulcanites and sediments (8), granite gneisses (9), highly metamorphosed and TTG complexes (10); (11, 12)Sumian laminated intrusions (11) and charnockites (12); (13) White Sea mobile belt (WSMB); (14, 15) WSMB borders: shear(14) and thrust (15); (16) sites of sampling for microprobe testing of zircons.andesibasalts, 2.5–2.4 Ga), and at Sariolian polymicticconglomerates (2.4–2.3 Ga).The monofraction of zircons includes several graintypes different in size, occurrence and composition ofmineral inclusions, character of variations, and thepresence and type of zonality, which was found whenthey were studied with a VEGA II LSH set (analystA.N. Safronov), with the following local U–Pb datingusing a SHRIMP II ion microprobe (analyst I.P. Paderin).All of the 46 zircon grains implanted into theplate were rounded. The grain size and elongationcoefficient varied within 150–350 µm and 1.1–3.3,DOKLADY EARTH SCIENCES Vol. 431 Part 1 2010

320KOZHEVNIKOV et al.Goyazite–florencite2871 ± 212681 ± 1550 µmQuartz5883-32698 ± 14 100 µm100 µm2867 ± 15S-3976ThoriteGematiteQuartz–OrthoclaseApatite80 µm5883-2QuZr15883-25Zr220 µmApFig. 2. CL and BSE images of zircons treated.206 Pb/ 238 U0.90.70.50.30.10.950.850.750.650.550.45Sample S-3976n = 9118002200Sample 5883n = 43220026002600300030003400340038003800400040000.350 10 20 30 40 50207 Pb/ 235 UFig. 3. Diagrams with the concordance for zircons fromJatulian terrigenous rocks.relatively. About a quarter of the grains were roundedfragments of large zircon crystals. Most of the grainsshowed oscillation zonality; three grains were characterizedby sectorial zonality, and one grain of 2681 ±15 Ma concordant age (U 128 ppm and U/Th = 2.5)was homogenous in CL (Fig. 2). Sixteen grains containedno mineral inclusions; the remaining 30 grainscontain inclusions of quartz, biotite, apatite, feldspar,thorite, and iron hydroxide. The inclusions and thoseof hydroxyl-containing minerals as well are oftenlocalized in the centers of zircon grains. The age determinedat five points of the grains as such was from2691 ± 22 to 2704 ± 43 Ma (U 36–358 ppm, U/Th =0.74–1.62). In eight grains, we found syngeneticinclusions of microcrystalline intergrowths of phosphatesfrom the group of florencite–goyazite–gorceixite(Fig. 2). The ages of zircons containing theseinclusions were 2867 ± 15 to 2871 ± 21 Ma (U 68–102 ppm, U/Th = 1.03–1.20), 2698 ± 14 Ma(U 130 ppm, U/Th = 1.2), and 2642 ± 21 Ma(U 532 ppm, U/Th = 2.18). The large fraction of zircongrains with phosphate inclusions (to 20%) showsthat low-depth granitic pegmatites characterized bythese minerals were probably present in a destroyedsource.In studying the isotope systems at 91 points of zircongrains by means of the LA–ICP–MS technique atthe Arizona Laserchron Center (Tucson, UnitedStates) by the procedure of [15] (Fig. 3, table), widerangevariations were found for the U, Th, and Pb content,U/Th ratio, and concordance value (C), as wellas the multimodal distribution of ages (Fig. 4). Thewhole set of grains included 2 Eoarchean (3.6–3.85Ga), 3 Paleoarchean (3.2–3.6 Ga), 57 Mesoarchean(2.8–3.2 Ga), and 29 Neoarchean (2.5–2.8 Ga)zircon grains. Two Eoarchean grains of 3837.2 ± 42.1and 3650.5 ± 21.7 Ma showed close characteristics (U116 and 123 ppm, U/Th = 2.1 and 1.5, C = 100.6 and100.2%). Somewhat less uranium was contained inDOKLADY EARTH SCIENCES Vol. 431 Part 1 2010

HADEAN–ARCHEAN DETRITAL ZIRCONS 321Isotope U–Th–Pb data for several representative grains of detrital zircons from Jatulian rocksIsotope ratioAge, MaPoint no. U, ppmU/Th206Pb*-----------207Pb*207Pb*206Pb*% ----------- % ----------- %235238U*U206Pb*-----------238Sample S 3976, Jatulian quartzite, Woloma structure90 38 0.7 5.6775 ±2.3 11.9084 ±2.4 0.4904 ±0.6 2572.2 ± 13.4 2616.8 ± 38.0 98.356 48 0.6 5.5673 ±2.6 12.8283 ±2.9 0.5180 ±1.3 2690.6 ± 28.6 2649.4 ± 42.5 101.619 207 1.4 5.3759 ±2.2 13.2621 ±3.2 0.5171 ±2.3 2686.8 ± 50.5 2707.2 ± 35.8 99.221 30 0.5 5.2359 ±0.9 14.0563 ±1.0 0.5338 ±0.5 2757.4 ± 11.2 2750.7 ± 14.8 100.223 181 1.9 5.1575 ±1.5 14.3475 ±3.3 0.5367 ±2.9 2769.5 ± 65.3 2775.5 ± 24.4 99.864 256 1.3 5.0394 ±2.6 15.1104 ±3.2 0.5523 ±1.9 2834.6 ± 42.4 2813.4 ± 43.0 100.870 28 1.2 5.0278 ±2.9 15.2377 ±3.2 0.5556 ±1.3 2848.6 ± 30.9 2817.1 ± 48.0 101.188 110 0.9 4.5708 ±2.0 17.7313 ±2.9 0.5878 ±2.1 2980.5 ± 49.6 2971.7 ± 31.9 100.32 40 0.7 4.5608 ±1.4 17.8442 ±1.5 0.5903 ±0.6 2990.4 ± 13.4 2975.2 ± 23.2 100.563 93 1.4 4.2743 ±1.7 19.8042 ±2.0 0.6139 ±1.1 3085.8 ± 27.2 3079.3 ± 27.1 100.277 69 2.1 4.1478 ±1.6 20.7384 ±1.7 0.6239 ±0.5 3125.3 ± 12.6 3127.2 ± 25.5 99.927 84 1.6 3.7634 ±2.3 24.6163 ±3.1 0.6719 ±2.1 3313.2 ± 55.2 3280.9 ± 36.3 101.068 101 2.1 3.7174 ±4.0 25.1330 ±4.3 0.6776 ±1.7 3335.2 ± 44.0 3300.2 ± 62.8 101.1100 51 2.3 3.4717 ±2.5 27.8663 ±2.9 0.7017 ±1.4 3426.9 ± 37.2 3407.1 ± 39.1 100.61 123 1.5 2.9648 ±1.4 35.5125 ±1.6 0.7636 ±0.8 3657.5 ± 23.2 3650.5 ± 21.7 100.299 116 2.1 2.6220 ±2.8 43.1147 ±3.0 0.8199 ±1.0 3860.0 ± 29.3 3837.2 ± 42.1 100.6Sample 5883, cement of Jatulian conglomerate, Onega syncline22 89 1.1 5.3794 ±2.0 12.1443 ±2.9 0.4738 ±2.1 2500.3 ± 43.1 2706.2 ± 32.2 92.446 20 1.3 5.2089 ±2.4 13.9498 ±2.7 0.5270 ±1.2 2728.8 ± 26.3 2759.2 ± 39.7 98.957 20 0.9 5.1158 ±3.0 14.5726 ±3.1 0.5407 ±0.5 2786.3 ± 12.0 2788.8 ± 49.5 99.920 114 1.1 4.8181 ±2.9 15.8609 ±3.1 0.5542 ±1.1 2842.8 ± 24.4 2886.5 ± 46.9 98.518 71 1.5 4.7686 ±2.3 16.5862 ±2.6 0.5736 ±1.2 2922.7 ± 28.9 2903.2 ± 37.4 100.729 115 1.1 4.4560 ±1.5 17.7840 ±2.6 0.5747 ±2.1 2927.3 ± 49.6 3012.6 ± 24.3 97.219 141 1.1 4.4145 ±1.0 18.5633 ±1.8 0.5943 ±1.5 3007.0 ± 35.6 3027.7 ± 15.4 99.348 7 1.0 4.3379 ±3.7 19.2363 ±3.8 0.6052 ±0.5 3050.8 ± 12.2 3055.7 ± 59.7 99.825 177 1.0 4.1743 ±1.9 20.4015 ±4.0 0.6177 ±3.5 3100.6 ± 85.2 3117.0 ± 30.7 99.549 57 1.3 4.0014 ±2.8 21.7602 ±3.0 0.6315 ±1.2 3155.5 ± 30.2 3184.2 ± 43.7 99.123 174 0.3 3.9035 ±4.0 23.1427 ±4.1 0.6552 ±0.6 3248.4 ± 16.4 3223.4 ± 63.6 100.836 46 0.9 3.9000 ±1.9 21.9521 ±2.2 0.6209 ±1.1 3113.6 ± 27.2 3224.8 ± 30.0 96.637 113 2.1 3.8838 ±1.8 21.9925 ±1.9 0.6195 ±0.7 3107.9 ± 18.0 3231.3 ± 28.2 96.253 155 1.6 3.8512 ±2.5 23.1483 ±2.7 0.6466 ±1.0 3214.8 ± 25.8 3244.6 ± 39.4 99.133 76 0.8 3.7209 ±4.3 24.4125 ±4.6 0.6588 ±1.7 3262.5 ± 43.3 3298.8 ± 67.7 98.940a, core 9 1.7 2.5632 ±2.6 44.1950 ±2.6 0.8216 ±0.5 3866.0 ± 14.5 3871.5 ± 38.6 99.940, shell 12 0.6 5.3507 ±2.8 13.0916 ±3.0 0.5080 ±1.0 2648.3 ± 21.5 2715.0 ± 46.4 97.5U*206Pb*-----------207Pb*C, %three Paleoarchean grains of 3407.1–3280.9 Ma age(U 51–101 ppm, U/Th = 1.6–2.3, C = 100.6–101.1%). Within the distribution of other grains, fourtime intervals are distinguished, conforming to thepeaks in the age histogram: 3.00–3.15 (5 grains),2.95–3.00 (10 grains), 2.75–2.85 (32 grains), and2.6–2.65 Ga (2 grains). Each of these intervalsincludes grains that are much different in the U content,U/Th ratio, and concordance value. Thus, in theage cluster of 2.75–2.85 Ga, the main peak in the PDdiagram (Fig. 4) presents two groups of grains: thenumerous low-uranium (22 grains; U 28–94 ppm,U/Th = 0.4–3.2, C = 70.4–101.2%) and the higheruranium (U 105–338 ppm, U/Th = 0.9–4.1, C =DOKLADY EARTH SCIENCES Vol. 431 Part 1 2010

322KOZHEVNIKOV et al.No.2015105Sample S-3976n = 910109 Sample 5883n = 438765432102000 2400 2800 3200 3600 4000MaFig. 4. Multimodal distribution of 207 Pb/ 206 Pb ages of zirconsfrom the samples S-3976 and 5883 in PD diagrams.72.1–102.6%). The other intervals contained aboutequal numbers of high- and low-uranium grains.The second sample 5883 of about 15 kg mass wastaken from the bottoms of the upper layer of finegrainedpebbled quartz conglomerates with quartz–feldspar cement, in the section of sedimentary andvolcanogenic rocks of Jatulium at the western boundaryof the Onega syncline. The detrital accessory mineralswere presented by zircon, tourmaline, garnet,titanite, titano-magnetite, and thorite.Zircons were divided into two large groups by theirmorphology, mineral inclusions, and transformationdegree. The first group was presented by light pinktransparent fine grains (75–200 µm) of various roundnessdegree or of retained faceting, with a weak zonalityin most of the cases (Fig. 2). The fine syngeneticmonophase mineral inclusions in these zircons werepresented by quartz, feldspars, and F-apatite. Notransformations were revealed in this group of zircons.The second group is formed by coarser zonal grains(125–350 µm), from rounded muddy brown–cherrycoloredto poorly rounded brown and pink ones ofhyacinth habit. In the grains of this group, syngeneticmono- and polyphase inclusions of thorite, monazite,anorthoclase, Cl-apatite, quartz, biotite, chlorite,pyrite, titanomagnetite, and iron hydroxide werefound. The intense transformations of zircon accompaniedwith the supply of Th (to 0.43 wt %), Mn (to0.63 wt %), Al (to 1.95 wt %), Fe (to 2.64 wt %), Ca (to1.61 wt %), Na (to 0.96 wt %), Hf (to 0.46 wt %), andlight REEs (to 0.72 wt %) were revealed zonally aspatches and dendritic systems. The microveinlets wereformed by quartz and apatite (Fig. 2). Outgrowths ofchlorite, biotite, caolinite, and globular zircon intergrowthswith thorite were observed, as well as those ofrutile with hematite.The study of the isotope system at 43 points (Fig. 3,table) showed wide variations in the U, Th, and Pbcontents, the U/Th ratios, and the concordance values(C), as well as the multimodal age distribution (Fig. 4).The most ancient Hadean age value of 3871.5 ±38.6 Ma is related to the core part of a grain of the leasturanium content (U 9 ppm, U/Th = 1.7, C = 99.9%).The age of the metamorphic shell around the core wasdetermined as 2715 ± 46.4 Ma (U 12 ppm, U/Th =0.6, C = 97.5%). The remaining set of the grains in thePD diagram is subdivided into four age clusters of pronouncedlydifferent uranium content. Cluster 1(3150–3247 Ma) included two low-uranium grains(U 46–57 ppm, U/Th = 0.9–1.3, C = 96.6–99.1%) andsix higher-uranium ones (U 113–266 ppm, U/Th =0.3–24.5, C = 96.2–100.8%). Cluster 2 (2903–2946 Ma)contained eight grains among which five were lowuraniumones (U 18–71 ppm, U/Th = 0.9–3.8, C =98.2–100.7%) and three were higher uranium (U 121–289 ppm, U/Th = 0.9–3.8, C = 96.0–100.6%). Incluster 3 (2819–2846 Ma), four grains were low-uranium(U 25–62 ppm, U/Th = 1.2–1.5, C = 96.2–98.4%) and one was higher uranium (U 216 ppm,U/Th = 1.2, C = 100.9%). Cluster 4 (2706–2743 Ma)was formed by six grains of low uranium content(U 12–89 ppm, U/Th = 0.6–1.8, C = 92.4–98.6%).Most probably, these grains were metamorphic andanalogous to zircon in the shell of a grain with aHadean-age core.The common characteristics of the treated detritalzircons from Jatulian terrigenous rocks located at differentsites of the Karelian craton are the multimodaldistribution of their ages within 2.61–3.87 Ga and theheterogeneity of the grain sampling in the morphology,mineral inclusions, and geochemistry of fresh andtransformed parts of grains testifying to the heterogeneityof their sources. Quite a synchronous growth ofzircon grains differing greatly in U and Th contentmight represent the evolution of fluidal conditionsunder the transformations of crystallized or metamorphosedacidic crust rocks.The isotope ages obtained for detrital zircons makea substantial contribution to the Early Precambrianscale of isotope age for the Fennoscandian shield andopen the prospects for discovering a detrital substancerelated to the Hadean–Mesoarchean impact events.The detection of the oldest zircons gives the precondi-DOKLADY EARTH SCIENCES Vol. 431 Part 1 2010

HADEAN–ARCHEAN DETRITAL ZIRCONS 323tions for more valid global correlations to the mostancient terrestrial areas, first, to those of Greenlandand North America.ACKNOWLEDGMENTSThis study was supported by Program 2.3.2009 ofthe Russian Academy of Sciences, the Russian Foundationfor Basic Research (project no. 08-05-98815-r_sever_a), and the Arizona Laserchrone Center(project nos. NSF-EAR 0443387 and 0732436).REFERENCES1. D. O. Froude, T. R. Ireland, P. D. Kinny, et al., Nature304, 616–618 (1983).2. T. Komiya, S. Maruyama, T. Masuda, et al., J. Geol.107, 515–554 (1999).3. N. L. Cates, and S. Mojzsis, in Proc. of the GoldschmidtConf. 2004 (Copenhagen, 2004), Abstr. A744.4. K. N. Sircombe, W. Bleeker, and R. Stern, in Proc. ofthe 4th Intern. Archaean Symp. Ext., AGSO-GeoscienceAustral. Record 37, 263–265 (2001).5. P. A. Mueller, J. L. Wooden, and A. P. Nutman, Geology20, 327–330 (1992).6. A. P. Nutman and K. D. Collerson, Geology 19, 791–794 (1991).7. D. Y. Liu, A. P. Nutman, W. Compston, et al., Geology20, 339–342 (1992).8. A. Zeh, A. Gerdes, R. Klemd, et al., Geochim. Cosmochim.Acta 72, 5304–5329 (2008).9. A. P. Nutman, Precambrian Res. 105, 93–114 (2001).10. T. A. Myskova, N. G. Berezhnaya, V. A. Glebovitskii,et al., Dokl. Akad. Nauk 402, 82–85 (2005).11. S. Claesson, H. Huhma, P. D. Kinny, et al., PrecambrianRes. 64, 109–130 (1993).12. V. N. Kozhevnikov, N. G. Berezhnaya, S. L. Presnyakov,et al., Stratigr. Geol. Korrelyatsiya 14 (3), 19–41(2006) [Stratigr. Geol. Correlation 14, 240–259(2006)].13. T. Mutanen and H. Huhma, Bull. Geol. Soc. Finl. 75,51–68 (2003).14. D. Bridzhuoter, D. Skott, V. V. Balaganskii, et al., Dokl.Akad. Nauk 366, 664–668 (1999).15. G. E. Gehrels, V. A. Valencia, and J. Ruiz, Geochem.Geophys. Geosyst. 9, Q03017 (2008),doi:10.1029/2007GC001805.DOKLADY EARTH SCIENCES Vol. 431 Part 1 2010