Hf isotopic composition of single zircons from Neoproterozoic arc volcanics and post-collision granites, Eastern Desert of Egypt: Implications for crustal growth and recycling in the

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Contents lists available at SciVerse ScienceDirect

Precambrian Research

jou rn al h om epa ge: www.elsev ier .com/ locate /precamres

f isotopic composition of single zircons from Neoproterozoic arcolcanics and post-collision granites, Eastern Desert of Egypt:mplications for crustal growth and recycling in the Arabian-Nubianhield

amal A. Alia,c,∗, Simon A. Wildeb, Robert J. Sternc, Abdel-Kader M. Moghazia,d,.M. Mahbubul Ameene,b

Department of Mineral Resources and Rocks, Faculty of Earth Sciences, King Abdulaziz University, P.O. Box 80206, Jeddah 21589, Saudi ArabiaDepartment of Applied Geology, Curtin University, Perth, 6845 WA, AustraliaGeosciences Department, University of Texas at Dallas, 800 W Campbell Road, Richardson, TX 75080, USADepartment of Geology, Faculty of Science, Alexandria University, Alexandria, EgyptDepartment of Geological Sciences, Jahangirnagar University, Dhaka 1342, Bangladesh

a r t i c l e i n f o

rticle history:eceived 5 September 2012eceived in revised form 9 March 2013ccepted 21 May 2013vailable online xxx

eywords:rabian-Nubian Shield

a b s t r a c t

Zircon Hf isotopic compositions for Neoproterozoic igneous rocks in the Central Eastern Desert of Egyptare presented and interpreted. The Humr Akarim (633 ± 7 and 603 ± 9 Ma)–Humrat Mukbid (625 ± 8 and619 ± 8 Ma) plutons are Early Ediacaran post-collsional subsolvus granites. Their zircon ages range from0.57 to 0.71 Ga, with high positive �Hf(T) values of +4.0 to +11.9. Hf model ages (Hf-TDM

c) of 0.81–1.3 Ga,are close to the U–Pb crystallization ages. These isotopic characteristics, along with published whole-rock Nd isotopic data, indicate that the protoliths were juvenile. The Wadi Kareim and Wadi El-Dabbahmetavolcano-sedimentary rocks are Cryogenian (∼750 Ma) arc-related metabasalts, meta-andesites and

f-isotopeseoproterozoic crustgyptingle-zircon Hf-isotopes

meta-tuffs. Their U–Pb zircon age populations range between 0.7–0.9, 0.9–1.5 Ga and 2.0–3.0 Ga. Theyoungest group represents magmatic zircons in the metavolcanics or reworked Neoproterozoic rocks inthe metasediments. The 0.9–1.5 Ga and 2.0–3.0 Ga age groups are similar to those in pre-Neoproterozoicrocks that surround the Arabian-Nubian Shield and represent inherited or older detrital grains. The highlyvariable �Hf(T) values (+23.5 to −35.0) and Hf-TDM

c ages (0.78–3.8 Ga) of Neoproterozoic zircons indicatethat at least some of these magmas interacted with a pre-Neoproterozoic crustal source.

© 2013 Elsevier B.V. All rights reserved.

. Introduction

The Arabian-Nubian Shield (ANS) is dominated by Neoprotero-oic crust formed between 550 and 900 Ma through the accretion ofntra-oceanic arcs leading to the closure of the Mozambique Oceannd the amalgamation of Gondwana (Collins and Pisarekvsky,005; Johnson and Woldehaimanot, 2003; Stern, 1994, 2002, 2008;tern and Johnson, 2010). Formation of the ANS records ∼300 m.y.

Please cite this article in press as: Ali, K.A., et al., Hf isotopic compositcollision granites, Eastern Desert of Egypt: Implications for crustal growth

http://dx.doi.org/10.1016/j.precamres.2013.05.007

f orogenic evolution from intra-oceanic subduction, arc and back-rc magmatism (870–700 Ma), through terrane amalgamation∼800 to 650 Ma) to terminal collision between major fragments of

∗ Corresponding author at: Department of Mineral Resources and Rocks, Facultyf Earth Sciences, King Abdulaziz University, P.O. Box 80206, Jeddah 21589, Saudirabia. Tel.: +966 2 640 0579; fax: +966 2 695 2095.

E-mail addresses: [email protected], [email protected],[email protected] (K.A. Ali).

301-9268/$ – see front matter © 2013 Elsevier B.V. All rights reserved.ttp://dx.doi.org/10.1016/j.precamres.2013.05.007

East and West Gondwana, with attendant tectonic escape, strike-slip faulting, delamination, and extension (630–550 Ma) of thenewly formed continental crust (Stoeser and Camp, 1985; Kröner,1985; Kröner et al., 1987; Stern, 1994; Genna et al., 2002; Johnsonand Woldehaimanot, 2003; Hargrove et al., 2006a,b; Avigad andGvirtzman, 2009; Stern and Johnson, 2010; Johnson et al., 2011).This formed the East African Orogen (Stern, 1994; Johnson andWoldehaimanot, 2003; Fritz et al., in press). Pre-Neoproterozoiccrust (Archean and Paleoproterozoic) is structurally intercalatedwith juvenile Neoproterozoic rocks in the southern, western andeastern ANS (Fig. 1). Old crust has long been recognized in theAl-Mahfid Terrane of Yemen (Whitehouse et al., 1998), in theKhida sub-terrane of eastern Saudi Arabia (Stacey and Hedge,1984; Stoeser et al., 2001; Windley et al., 1996; Agar et al., 1992;

ion of single zircons from Neoproterozoic arc volcanics and post-and recycling in the Arabian-Nubian Shield. Precambrian Res. (2013),

Whitehouse et al., 2001) and along the western sides of the ANSin contact with the African Sahara metacraton (Abdelsalam et al.,1998, 2002; Küster et al., 2008). ∼1.0 Ga crust was recently docu-mented from the northern ANS in Sinai (Be’eri-Shlevin et al., 2012).

dx.doi.org/10.1016/j.precamres.2013.05.007


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ARTICLE IN PRESSG Model

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Fig. 1. Map of the Arabian–Nubian Shield (modified from Stern et al., 2006), showing the location of the study areas and regions where pre-Neoproterozoic crust has beenidentified.

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ges for pre-Neoproterozoic crustal tracts are from Whitehouse et al. (1998), Sultannd Rumvegeri (1993).

Numerous studies over the past few decades, including U–Pbircon and Nd isotope data, indicate that magmas from depletedantle sources produced most ANS crust (e.g., Dixon andolombek, 1988; Moghazi et al., 1998; Stern, 2002; Moussa et al.,008; Andresen et al., 2009; Stern et al., 2010; Ali et al., 2009b,010a,c; Liégeois and Stern, 2010; Moghazi et al., 2012). Nd modelges (Nd-TDM = ca. 0.80–1.30 Ga) and initial epsilon Nd (�Nd(T) = +1o +8) of the island arc and post-collisional rocks of the ANS are sim-lar, indicating little or no pre-Neoproterozoic rocks are present inhe lower to middle crust (Stern, 2002; Stoeser and Frost, 2006;yal et al., 2010). This inference is supported by the U–Pb dating ofndividual zircon grains from various plutonic rocks (Be’eri-Shlevint al., 2009) and by radiogenic isotope studies of whole-rock sam-les of Neoproterozoic granite–gneiss in the Eastern Desert of EgyptLiégeois and Stern, 2010). However, pre-Neoproterozoic zirconsre increasingly recognized in juvenile ANS igneous rocks of Cryo-



enian age (Sultan et al., 1990; Kröner et al., 1992; Kennedy et al.,004; Loizenbauer et al., 2001; Hargrove et al., 2006a,b; Ali et al.,009a,b, 2010b,c; Stern et al., 2010). These pre-Neoproterozoicenocrysts indicate a contribution from an older crustal component

(1994), Agar et al. (1992), Kröner and Sassi (1996), Stern et al. (1994), and Walraven

to the ANS juvenile rocks, which is generally not reflected bytheir whole-rock radiogenic isotope data (e.g., Liégeois and Stern,2010). Pre-Neoproterozoic zircons are not found in all ANS igneousrocks; felsic plutonic rocks tend to lack these xenocrystic zir-cons (Moussa et al., 2008; Andresen et al., 2009; Ali et al., 2012b;Lundmark et al., 2012), whereas mafic lavas may carry them inabundance (Hargrove et al., 2006a; Ali et al., 2009b, 2010c; Sternet al., 2010). The occurrence of these xenocrystic zircons indi-cates either incorporation of continentally derived sediments orinheritance from the mantle source region, or both (Stern et al.,2010).

Understanding the significance of pre-Neoproterozoic zircons injuvenile ANS crust can be advanced by studying radiogenic isotopiccompositions, for example, whole-rock 143Nd/144Nd studies. Suchstudies provide important information about the time-averaged147Sm/144Nd of likely source regions, especially continental crust


(low 143Nd/144Nd) or depleted mantle (high 143Nd/144Nd) (Dickin,2005; DePaolo et al., 1991, 1992). This allows other chemical char-acteristics of the source region to be inferred. Where such studieshave been conducted for Neoproterozoic ANS igneous rocks, little


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vidence is found to indicate that older crust was involved (Stern,002).

Recent technologic advances have enabled the in situ analysisf Hf isotopes in zircon (Patchett et al., 1981; Vervoort et al., 1996;cherer et al., 2000, 2001). This has advantages over the Sm/Ndhole-rock system as a tracer of magma source and petroge-etic processes (Dickin, 2005), summarized as follows: (1) zirconsave high Hf and low Lu concentrations, hence low 176Lu/177Hf,o their present-day Hf isotopic compositions approximate thosef magmas from which the zircons crystallized. This will have76Hf/177Hf consistent with evolution in a reservoir with low origh 176Lu/177Hf, i.e. continental crust or mantle; (2) Hf forms an

ntegral part of the zircon crystal lattice, which is a robust min-ral with remarkable resistance to re-equilbration of Hf isotopicomposition (Watson, 1996; Watson and Cherniak, 1997), so its Hfsotopic compositions are not disturbed even by magmatic pro-esses or high-grade metamorphism (e.g., Huang et al., 2006);nd (3) discrete domains in zircons can be individually dated by–Pb techniques, which can reveal metamorphic overprinting orhether individual zircons are inherited.

As a result of the above considerations, zircon Lu–Hf isotopicompositions provide a powerful tool for inferring the sources ofircon-bearing igneous rocks (e.g., Griffin et al., 2002; Belousovat al., 2010; Kemp et al., 2007) and for tracing crustal growth (e.g.,lichert-Toft et al., 1999; Andersen et al., 2002; Griffin et al., 2002;ondie et al., 2005; Zheng et al., 2006; Zhao et al., 2008).

In spite of the afore-mentioned advantages, Lu–Hf isotopic stud-es of zircons are only beginning to be applied to the ANS. As partf our studies of the ANS, we report Hf isotopic analyses of zirconeparates from two occurrences of Cryogenian arc volcanics (Wadiareim and Wadi El-Dabbah; Ali et al., 2009b) and two Ediacaranost-collisional granite plutons (Humr Akarem and Humrat Muk-id plutons; Ali et al., 2012b) in the Central Eastern Desert (CED)f Egypt (Fig. 1). These two regions are separated by ∼300 km andepresent, respectively, early supracrustal sequences and late intru-ions. This study contributes to resolving the controversy abouthe significance of pre-Neoproterozoic xenocrystic zircons in juve-ile ANS crust (Stern et al., 2010). In addition, the investigatedock types are characterized by juvenile Nd isotopic compositionsAli et al., 2009b, 2012b) and thus enable us to investigate howf isotopic compositions vary in comparison with Nd whole-rock

sotopic compositions of the host igneous rocks.

. Geologic background and petrography

.1. Wadi Kareim and Wadi Dabbah

The Wadi Kareim and Wadi El-Dabbah areas (Fig. 2a) are partf the island arc volcanic sequence in the Eastern Desert of EgyptStern, 1981; Ali et al., 2009b). They were dated at ∼750 Ma (U–Pbircon SHRIMP) with positive initial �Nd (+5.1 to +8.9) and Ndodel ages of 0.64–0.79 Ga, indicating a juvenile crust that was

xtracted from a depleted mantle source (Ali et al., 2009b). Rocknits around Wadi El-Dabbah include Cryogenian serpentinitend talc-carbonate, metavolcanic rocks, metasedimentary rocks,ncluding banded iron formation (BIF), which are overlain by Edi-caran Hammamat sediments. The metavolcanics lie structurallybove serpentinite and talc carbonate rocks and are intruded byumerous plutons, ∼700 Ma and younger in the region around Jaball-Sibai (Fig. 2A; Bregar et al., 2002). In the Wadi Kareim area theolcanic rocks are conformably overlain by Atud diamictite, imma-



ure metasediments, with Banded Iron Formation (BIF) (Ali et al.,009b, 2010b). About 100 m-thick sequence of metavolcanic rockst the base of the section is thrust over younger Hammamat sed-ments to the south, marking the northern margin of the Kareim

PRESSarch xxx (2013) xxx– xxx 3

Basin (Ali et al., 2009b). The metavolcanic rocks in the Wadi Kareimand Wadi El-Dabbah areas are mainly metabasalt, meta-andesiteand tuffaceous metasediments affected by greenschist-facies meta-morphism. Metabasalt consists of plagioclase (groundmass andphenocrysts) and interstitial clinopyroxene. Plagioclase has alteredcores and less altered rims and clinopyroxene is altered to actinoliteand chlorite. Accessory minerals are apatite, zircon and Fe-oxides.The meta-andesite consists of plagioclase, actinolite, clinopyrox-ene, quartz, and chlorite and calcite are secondary minerals dueto alteration. Plagioclase forms altered phenocrysts; clinopyroxeneoccurs as relicts; actinolite replaces clinopyroxene, while quartzis present as anhedral grains. Calcite occurs as patches and veins,and accessory minerals are apatite and Fe-oxides. The tuffaceousmetasediments are intercalated with BIF, which demonstratesthat the succession formed in a submarine environment. Theseare greenish meta-mudstones consisting of anhedral, fine-grainedquartz, lithic fragments, and calcite patches set in a matrix of clay,chlorite, and Fe-oxides.

2.2. Humr Akarim and Humrat Mukbid areas

Country rocks in the Humr Akarim and Humrat Mukbid areasinclude a Cryogenian metavolcano-sedimentary association simi-lar to that of the Wadi Kareim and Wadi El-Dabbah areas to the N,along with metagabbro, gneiss, and tonalite-granodiorite (Fig. 2b),which all belong to the island arc stage of the ANS (e.g., Hassanenand Harraz, 1996; Abd El-Naby et al., 2000; Saleh et al., 2002). Edi-acaran (post-collisional) granites are the youngest rock units (Aliet al., 2012b) and the two bodies that we studied occur as two dis-tinct plutons; Humr Akarim in the west and Humrat Mukbid in theeast (Fig. 2b). U–Pb SHRIMP zircon dating (Ali et al., 2012b) indi-cates concordia ages of 633 ± 7 and 603 ± 9 Ma for Humr Akarimand 625 ± 8 and 619 ± 8 Ma for Humrat Mukbid with slightly olderzircons (∼740 Ma, 703 Ma), may have been inherited from oldergranites in the region (Ali et al., 2012b). The Humr Akarim pluton isa NE-elongated irregular body that is ∼6 km in maximum dimen-sion (Fig. 2b). It intrudes quartzo-feldspathic and volcanoclasticmetasedimentary rocks, which are regionally metamorphosedup to greenschist facies (Geological Map of Egypt, 1987). Theintrusion consists of medium- to coarse-grained alkali granite. Con-tacts between the granite and country rocks are irregular. TheHumrat Mukbid pluton intrudes gabbro-diorite-granodiorite andmetavolcanic-metasedimentary rocks (Fig. 2b). Contacts are poorlyexposed due to weathering and erosion. The pluton is up to 7 kmlong and consists of two alkali granite masses. Granitic rocks ofHumr Akarim and Humrat Mukbid are mineralogically and textu-rally similar. Both are equigranular and composed dominantly ofperthitic alkali feldspar (50%), quartz (30%), plagioclase (15%) andsubordinate biotite and muscovite (4%). Zircon, fluorite, apatite,and allanite are the main accessory minerals (∼1%), and titaniteis locally present. Biotite and muscovite are subhedral and intersti-tial between feldspars. In Humrat Mukbid, biotite is more abundantthan muscovite, whereas in parts of the Humr Akarim pluton, mus-covite exceeds biotite.

3. Analytical techniques

Nine samples from the Wadi Kareim-Wadi El-Dabbah volcano-sedimentary belt and two samples from the Humrat Mukbid-Humr Akarim granite plutons were chosen for Hf isotope anal-yses (Table 1). These include 2 metasediments, 7 metavolcanics,


and 2 plutonic rocks. These samples were previously analyzed forU–Pb zircon age (Ali et al., 2009b, 2012b) using both the high mass-resolution ion microprobe with reverse geometry (SHRIMP-RG) atthe SUMAC facility co-managed by the U.S. Geological Survey and


Please cite this article in press as: Ali, K.A., et al., Hf isotopic composition of single zircons from Neoproterozoic arc volcanics and post-collision granites, Eastern Desert of Egypt: Implications for crustal growth and recycling in the Arabian-Nubian Shield. Precambrian Res. (2013),http://dx.doi.org/10.1016/j.precamres.2013.05.007




Fig. 2. (a) Geological map of the Humr Akarim and Humrat Mukbid areas, Eastern Desert, Egypt, showing the location of the alkali granite samples analyzed in this study;(b) geological map of Wadi Kareim and Wadi El-Dabbah, Central Eastern Desert, Egypt, showing the location of the metavolcanic samples analyzed in this study.





K.A. Ali et al. / Precambrian Research xxx (2013) xxx– xxx 5

Table 1LA-IC-PMS single zircon Lu–Hf isotopic data for the Eastern Desert of Egypt.

Spot t (Ma) 176Yb/177Hf 2� 176Lu/177Hf 2� 176Hf/177Hf 2� Hf(i) �Hf(T) 2� TDM TDMc

Wadi El-Dabbah metasediment #D1Lat. 25◦49′05′′ NLong. 34◦09′16′′ E

D1-01 1364 0.059475 0.001070 0.001780 0.000029 0.282249 0.000027 0.282203 10.2 1.0 1445 1490D1-02 2485 0.036411 0.000093 0.001063 0.000003 0.280956 0.000027 0.280905 −10.3 1.0 3194 3612D1-03 2496 0.026693 0.000032 0.000845 0.000001 0.281019 0.000026 0.280978 −7.5 0.9 3092 3448D1-04 2496 0.037471 0.000153 0.001139 0.000004 0.281039 0.000028 0.280985 −7.2 1.0 3087 3433D1-05* 2155 0.035078 0.000556 0.001025 0.000017 0.281258 0.000024 0.281216 −6.9 0.9 2781 3151D1-06* 2245 0.029226 0.000198 0.000811 0.000005 0.281210 0.000026 0.281175 −6.3 0.9 2831 3182D1-07 2127 0.040746 0.000783 0.001187 0.000020 0.281253 0.000025 0.281205 −7.9 0.9 2800 3193D1-08* 2245 0.050963 0.002070 0.001324 0.000049 0.280922 0.000025 0.280865 −17.3 0.9 3262 3849D1-09 1204 0.033931 0.000287 0.000967 0.000008 0.281867 0.000022 0.281845 −6.1 0.8 1943 2381D1-10 1204 0.054900 0.000056 0.001520 0.000002 0.281883 0.000025 0.281848 −6.0 0.9 1949 2374D1-11 2486 0.021558 0.000023 0.000671 0.000001 0.280911 0.000024 0.280879 −11.2 0.8 3222 3667D1-12 2486 0.036926 0.000143 0.001083 0.000004 0.280923 0.000028 0.280872 −11.5 1.0 3240 3683D1-13 1198 0.066823 0.000142 0.001828 0.000004 0.281912 0.000029 0.281871 −5.3 1.0 1924 2328D1-14* 678 0.055527 0.000156 0.001698 0.000006 0.281886 0.000027 0.281865 −17.2 1.0 1954 2671D1-15 2466 0.024525 0.000265 0.000770 0.000008 0.281087 0.000026 0.281050 −5.6 0.9 2994 3312D1-16 2762 0.033899 0.000126 0.001039 0.000004 0.280882 0.000025 0.280827 −6.7 0.9 3292 3605D1-17 2141 0.024868 0.000101 0.000741 0.000003 0.281306 0.000025 0.281276 −5.1 0.9 2696 3031

Wadi El-Dabbah metasediment #D13Lat. 25◦47′53′′ NLong. 34◦08′00′′ E

D13-01* 855 0.043474 0.000347 0.001336 0.000008 0.282398 0.000026 0.282376 4.9 0.9 1218 1427D13-02* 814 0.031572 0.000123 0.001242 0.000007 0.282409 0.000028 0.282390 4.5 1.0 1199 1422D13-03 761 0.038473 0.000156 0.001447 0.000004 0.282006 0.000026 0.281986 −11.0 0.9 1773 2352D13-04 696 0.094901 0.001337 0.003168 0.000040 0.282590 0.000023 0.282548 7.5 0.8 994 1143D13-05 729 0.049335 0.000450 0.001645 0.000015 0.281955 0.000031 0.281932 −13.6 1.1 1855 2490D13-06 614 0.038245 0.001710 0.001278 0.000057 0.282287 0.000018 0.282272 −4.1 0.6 1372 1811D13-07* 637 0.025466 0.000181 0.000999 0.000003 0.281862 0.000025 0.281850 −18.6 0.9 1951 2728D13-08 853 0.023398 0.000139 0.000784 0.000004 0.282483 0.000017 0.282470 8.2 0.6 1081 1218D13-09* 774 0.145141 0.000580 0.004507 0.000018 0.282270 0.000034 0.282205 −3.0 1.2 1526 1859D13-10* 705 0.071017 0.002272 0.002681 0.000078 0.282375 0.000039 0.282339 0.3 1.4 1297 1604D13-11* 716 0.070435 0.001214 0.002643 0.000048 0.282721 0.000038 0.282685 12.8 1.3 787 823D13-12 779 0.037829 0.000234 0.001395 0.000008 0.282020 0.000032 0.281999 −10.1 1.1 1752 2311D13-13 2267 0.011178 0.000058 0.000430 0.000003 0.281407 0.000018 0.281389 1.8 0.6 2538 2705D13-14* 2627 0.027752 0.000158 0.000961 0.000005 0.280951 0.000019 0.280902 −7.1 0.7 3192 3528

Wadi El-Dabbah metavolcanic #D25 (metabasalt)Lat. 25◦47′59′′ NLong. 34◦08′50′′ E

D25-01* 1408 0.042603 0.001346 0.001406 0.000042 0.282560 0.000029 0.282523 22.5 1.0 990 750D25-02 806 0.024294 0.000244 0.000928 0.000009 0.282651 0.000028 0.282637 13.0 1.0 850 876D25-03 738 0.031934 0.000314 0.001292 0.000014 0.282554 0.000032 0.282536 7.9 1.1 996 1145D25-13* 2572 0.042008 0.000744 0.001313 0.000022 0.282181 0.000029 0.282116 34.8 1.0 1522 915D25-14 584 0.059030 0.002065 0.001904 0.000075 0.281440 0.000032 0.281419 −35.0 1.1 2592 3703D25-15* 477 0.060133 0.000309 0.001952 0.000010 0.281838 0.000038 0.281820 −23.2 1.4 2036 2895D25-16 859 0.034252 0.001012 0.001252 0.000025 0.281515 0.000032 0.281494 −26.2 1.2 2445 3367D25-17 641 0.016359 0.000257 0.000639 0.000010 0.281897 0.000035 0.281890 −17.1 1.2 1885 2640

Wadi El-Dabbah metavolcanic #D7 (meta-andesite)Lat. 25◦49′54′′ NLong. 34◦09′06′′ ED7-01 797 0.038627 0.000165 0.001098 0.000005 0.281837 0.000019 0.281820 −16.1 0.7 1992 2694D7-02 1360 0.031060 0.000281 0.000929 0.000008 0.282196 0.000018 0.282172 9.0 0.6 1486 1561D7-03 1360 0.034497 0.000090 0.001024 0.000002 0.282166 0.000015 0.282139 7.8 0.5 1532 1633D7-04 2488 0.019135 0.000066 0.000566 0.000002 0.281097 0.000017 0.281070 −4.4 0.6 2965 3256D7-05 734 0.032019 0.000103 0.001023 0.000003 0.281826 0.000017 0.281811 −17.8 0.6 2003 2753D7-06 740 0.046121 0.000550 0.001469 0.000018 0.281874 0.000020 0.281854 −16.2 0.7 1959 2656D7-07 798 0.033175 0.000162 0.001039 0.000005 0.281849 0.000023 0.281833 −15.6 0.8 1972 2665D7-08 798 0.028154 0.000488 0.000861 0.000014 0.281857 0.000018 0.281844 −15.2 0.6 1952 2641

Wadi Kareim metavolcanic #K11-6 (metabasalt)Lat. 25◦56′29′′ NLong. 34◦02′22′′ EK11-6-01* 2060 0.019943 0.000397 0.000641 0.000012 0.280989 0.000022 0.280964 −18.0 0.8 3115 3755K11-6-02 1039 0.066423 0.000277 0.002208 0.000011 0.282478 0.000026 0.282435 11.1 0.9 1131 1180K11-6-03 633 0.018043 0.001044 0.000604 0.000038 0.282207 0.000037 0.282200 −6.3 1.3 1458 1959K11-6-10* 591 0.047888 0.000307 0.001965 0.000014 0.282323 0.000021 0.282301 −3.6 0.7 1346 1762K11-6-11 1262 0.054780 0.000423 0.001769 0.000012 0.282686 0.000020 0.282644 23.5 0.7 818 570K11-6-12 731 0.095621 0.002982 0.002702 0.000079 0.282235 0.000024 0.282198 −4.2 0.8 1502 1902K11-6-13 731 0.042718 0.000694 0.001317 0.000020 0.282247 0.000023 0.282229 −3.1 0.8 1429 1833K11-6-14 741 0.038672 0.000089 0.001376 0.000004 0.282213 0.000020 0.282194 −4.1 0.7 1479 1904K11-6-15 805 0.056424 0.000631 0.001951 0.000018 0.282074 0.000033 0.282045 −7.9 1.2 1700 2193K11-6-16* 633 0.064030 0.000335 0.002221 0.000009 0.282562 0.000022 0.282536 5.6 0.8 1009 1212K11-6-17* 926 0.053012 0.000229 0.001760 0.000007 0.281771 0.000042 0.281741 −16.0 1.5 2119 2786






Table 1 (Continued)


K11-6-18 819 0.023844 0.000262 0.000838 0.000009 0.282125 0.000027 0.282112 −5.3 1.0 1581 2037K11-6-19 819 0.044027 0.000147 0.001350 0.000005 0.282185 0.000023 0.282165 −3.4 0.8 1517 1920

Wadi Kareim metavolcanic #K11-8 (metabasalt)Lat. 25◦56′31′′ NLong. 34◦02′22′′ EK11-8-01 1029 0.013612 0.000353 0.000421 0.000009 0.282166 0.000018 0.282158 1.0 0.7 1508 1803K11-8-02 805 0.029839 0.000596 0.000991 0.000021 0.282593 0.000021 0.282578 10.9 0.7 932 1008K11-8-03* 2730 0.017799 0.000082 0.000575 0.000002 0.282382 0.000022 0.282352 46.8 0.8 1215 291K11-8-21 646 0.077677 0.001476 0.002401 0.000045 0.282593 0.000024 0.282564 6.9 0.8 968 1140K11-8-22 659 0.024298 0.001157 0.000766 0.000034 0.282556 0.000025 0.282546 6.6 0.9 979 1172K11-8-23 790 0.041938 0.001256 0.001529 0.000038 0.281944 0.000020 0.281921 −12.7 0.7 1864 2476K11-8-24 1006 0.032432 0.000645 0.001022 0.000019 0.282170 0.000021 0.282150 0.3 0.7 1526 1833K11-8-25 628 0.036378 0.000629 0.001278 0.000023 0.282328 0.000022 0.282313 −2.4 0.8 1314 1711K11-8-26 621 0.059199 0.004252 0.001924 0.000134 0.282540 0.000032 0.282517 4.7 1.1 1033 1260K11-8-27 627 0.042162 0.000771 0.001378 0.000022 0.282609 0.000024 0.282593 7.5 0.8 920 1088

Wadi Kareim metavolcanic #K11-9 (metabasalt)Lat. 25◦56′31′′ NLong. 34◦02′22′′ EK11-9-01 785 0.053214 0.001100 0.001681 0.000028 0.281818 0.000018 0.281793 −17.3 0.6 2049 2760K11-9-02* 2710 0.017854 0.000047 0.000552 0.000001 0.281175 0.000016 0.281146 3.4 0.6 2859 2951K11-9-03 1935 0.030100 0.000199 0.000980 0.000006 0.281088 0.000016 0.281052 −17.7 0.6 3009 3645K11-9-04* 2020 0.017376 0.000065 0.000561 0.000002 0.281212 0.000018 0.281191 −10.8 0.6 2809 3291K11-9-13 2505 0.026937 0.000050 0.000813 0.000001 0.281096 0.000019 0.281057 −4.4 0.7 2984 3271K11-9-18* 2351 0.028073 0.000145 0.000915 0.000003 0.281202 0.000018 0.281161 −4.3 0.7 2850 3146K11-9-19 730 0.023845 0.000271 0.000798 0.000009 0.281739 0.000019 0.281728 −20.8 0.7 2110 2938K11-9-20 782 0.029056 0.000150 0.001016 0.000006 0.281919 0.000018 0.281904 −13.5 0.7 1874 2520K11-9-21 2434 0.024110 0.000267 0.000732 0.000008 0.281132 0.000019 0.281098 −4.7 0.7 2931 3230K11-9-22* 738 0.044663 0.000131 0.001490 0.000004 0.281973 0.000018 0.281952 −12.7 0.7 1822 2440K11-9-23 2093 0.040938 0.000469 0.001254 0.000011 0.281126 0.000018 0.281076 −13.2 0.6 2978 3492K11-9-24 725 0.038761 0.000263 0.001312 0.000010 0.281963 0.000019 0.281945 −13.3 0.7 1827 2464

Wadi Kareim metavolcanic #K4G (metabasalt)Lat. 25◦56′39′′ NLong. 34◦02′09′′ EK4G-01 769 0.096190 0.003699 0.002978 0.000089 0.282143 0.000018 0.282100 −6.8 0.6 1649 2095K4G-02 711 0.065839 0.000863 0.001842 0.000025 0.282104 0.000022 0.282079 −8.8 0.8 1654 2178K4G-03* 518 0.009181 0.000088 0.000257 0.000002 0.282431 0.000018 0.282428 −0.7 0.6 1138 1524K4G-04* 558 0.034153 0.000188 0.001160 0.000007 0.282584 0.000021 0.282572 5.2 0.7 950 1179K4G-05 745 0.038304 0.000900 0.001451 0.000027 0.281982 0.000023 0.281962 −12.2 0.8 1807 2414K4G-06 1370 0.029497 0.000340 0.000919 0.000010 0.282181 0.000022 0.282158 8.7 0.8 1506 1587K4G-07 1370 0.035666 0.000151 0.001207 0.000005 0.281997 0.000022 0.281966 1.9 0.8 1774 2010K4G-08 767 0.015953 0.000036 0.000487 0.000001 0.281417 0.000018 0.281410 −31.3 0.6 2530 3610K4G-09* 783 0.124434 0.003684 0.003721 0.000101 0.282621 0.000020 0.282566 10.0 0.7 963 1049K4G-10 913 0.044332 0.000785 0.001431 0.000024 0.282393 0.000017 0.282368 5.9 0.6 1227 1408K4G-11 913 0.065362 0.000468 0.002059 0.000015 0.282443 0.000019 0.282408 7.3 0.7 1176 1320K4G-12* 1358 0.050954 0.001770 0.001446 0.000040 0.282207 0.000016 0.282170 8.9 0.6 1490 1566K4G-13 2092 0.044218 0.000926 0.001422 0.000026 0.280995 0.000018 0.280938 −18.2 0.6 3171 3790K4G-14 752 0.026304 0.000132 0.001002 0.000005 0.281945 0.000018 0.281931 −13.2 0.6 1837 2479K4G-15 679 0.027102 0.000367 0.001035 0.000017 0.282694 0.000016 0.282680 11.8 0.6 792 858K4G-16* 2396 0.063947 0.001321 0.001895 0.000036 0.281058 0.000022 0.280971 −10.0 0.8 3123 3526

Wadi Kareim metavolcanic #K4 K (meta-tuff)Lat. 25◦56′52′′ NLong. 34◦02′15′′ EK4K-01* 653 0.024697 0.000212 0.000910 0.000009 0.281920 0.000015 0.281909 −16.2 0.5 1867 2590K4K-02* 739 0.029667 0.000230 0.001048 0.000005 0.281915 0.000015 0.281900 −14.6 0.5 1882 2555K4K-03 746 0.029724 0.000654 0.001059 0.000022 0.281938 0.000016 0.281924 −13.6 0.6 1849 2499K4K-04 818 0.027400 0.000766 0.000985 0.000026 0.281734 0.000019 0.281719 −19.2 0.7 2127 2902K4K-05 776 0.060398 0.000382 0.001772 0.000010 0.282716 0.000018 0.282690 14.2 0.6 776 776K4K-06 784 0.046048 0.002079 0.001445 0.000060 0.281851 0.000018 0.281829 −16.1 0.6 1991 2682K4K-07* 744 0.106818 0.000329 0.003241 0.000006 0.282664 0.000021 0.282619 11.0 0.7 885 954K4K-08* 749 0.095016 0.004324 0.003344 0.000148 0.282770 0.000026 0.282722 14.8 0.9 729 719K4K-09* 749 0.117055 0.000202 0.003547 0.000006 0.282690 0.000019 0.282640 11.9 0.7 854 904

Humr Akarim granite #AK-6Lat. 24◦10′38′′ NLong. 34◦03′28′′ EAK6-01c 603 0.109491 0.001199 0.003767 0.000040 0.282696 0.000026 0.282653 9.1 0.9 851 968AK6-02* 567 0.160466 0.004469 0.005347 0.000136 0.282663 0.000051 0.282606 6.6 1.8 943 1095AK6-03 599 0.062883 0.001543 0.002151 0.000050 0.282690 0.000029 0.282666 9.5 1.0 821 942AK6-04 593 0.142914 0.001465 0.004599 0.000045 0.282634 0.000043 0.282583 6.4 1.5 968 1132AK6-05 603 0.085892 0.000876 0.002662 0.000025 0.282624 0.000025 0.282594 7.0 0.9 929 1099AK6-06 629 0.105555 0.004476 0.003136 0.000126 0.282598 0.000027 0.282561 6.4 1.0 981 1158AK6-07 611 0.082643 0.001645 0.002682 0.000049 0.282545 0.000035 0.282514 4.4 1.2 1047 1273AK6-08* 519 0.128894 0.001822 0.004146 0.000067 0.282702 0.000035 0.282661 7.5 1.2 851 1002AK6-09* 638 0.082831 0.004013 0.003014 0.000147 0.282642 0.000027 0.282606 8.2 0.9 912 1050AK6-10* 631 0.127431 0.001166 0.003855 0.000035 0.282583 0.000042 0.282538 5.6 1.5 1024 1208





Table 1 (Continued)


AK6-11* 497 0.081475 0.002394 0.002477 0.000069 0.282598 0.000028 0.282575 4.0 1.0 964 1210AK6-12c 603 0.093937 0.001946 0.002955 0.000058 0.282572 0.000030 0.282538 5.0 1.0 1015 1225AK6-13c 603 0.145162 0.001920 0.004715 0.000077 0.282632 0.000026 0.282578 6.5 0.9 974 1135AK6-12c 603 0.087357 0.002298 0.002867 0.000074 0.282666 0.000033 0.282634 8.4 1.2 873 1011AK6-13c 603 0.160763 0.003451 0.004772 0.000101 0.282719 0.000039 0.282665 9.5 1.4 839 941AK6-12c 603 0.225207 0.002689 0.006832 0.000089 0.282759 0.000059 0.282682 10.1 2.1 826 903AK6-13c 603 0.139472 0.005670 0.004889 0.000205 0.282699 0.000030 0.282644 8.8 1.1 873 988AK6-12c 603 0.093762 0.002426 0.002783 0.000071 0.282598 0.000046 0.282566 6.0 1.6 972 1163AK6-13c 603 0.092940 0.002618 0.002668 0.000069 0.282533 0.000045 0.282503 3.8 1.6 1064 1304AK6-12c 603 0.093161 0.001731 0.003038 0.000056 0.282631 0.000031 0.282597 7.1 1.1 929 1094AK6-13c 603 0.083175 0.001390 0.002501 0.000038 0.282616 0.000041 0.282587 6.8 1.4 938 1115AK6-12c 603 0.058345 0.002336 0.002048 0.000076 0.282636 0.000036 0.282613 7.7 1.3 896 1057AK6-13c 603 0.086475 0.001745 0.002931 0.000060 0.282593 0.000038 0.282560 5.8 1.3 982 1176AK6-12c 603 0.159417 0.002827 0.005454 0.000096 0.282632 0.000046 0.282570 6.2 1.6 995 1153AK6-13c 603 0.095029 0.004130 0.002925 0.000111 0.282585 0.000033 0.282552 5.5 1.2 995 1195AK6-12c 603 0.066153 0.002567 0.002084 0.000078 0.282541 0.000048 0.282517 4.3 1.7 1036 1272AK6-13c 603 0.209777 0.003394 0.007365 0.000138 0.282749 0.000043 0.282665 9.5 1.5 858 940AK6-12c 603 0.162333 0.009275 0.005341 0.000302 0.282624 0.000039 0.282563 5.9 1.4 1005 1169AK6-13c 603 0.079973 0.002707 0.002551 0.000089 0.282701 0.000049 0.282672 9.8 1.7 814 926AK6-12c 603 0.159663 0.007268 0.004559 0.000191 0.282559 0.000035 0.282508 3.9 1.3 1082 1293

Humrat Mukbid granite #MK19Lat. 24◦09′39′′ NLong. 34◦24′07′′ EMK19-01 703 0.038432 0.000299 0.001305 0.000010 0.282686 0.000037 0.282669 11.9 1.3 808 869MK19-02 622 0.137236 0.005241 0.004326 0.000165 0.282680 0.000051 0.282629 8.7 1.8 889 1009MK19-03 628 0.077223 0.000374 0.002534 0.000012 0.282672 0.000028 0.282642 9.3 1.0 857 977MK19-04 677 0.063136 0.001030 0.002310 0.000032 0.282692 0.000029 0.282662 11.1 1.0 822 900MK19-05 709 0.027821 0.000672 0.001122 0.000029 0.282628 0.000035 0.282614 10.1 1.2 886 989MK19-06 629 0.119543 0.001126 0.003616 0.000035 0.282692 0.000028 0.282649 9.5 1.0 852 959MK19-07 570 0.131452 0.004537 0.003774 0.000135 0.282770 0.000036 0.282730 11.1 1.3 737 816MK19-08 628 0.080328 0.000337 0.002705 0.000009 0.282657 0.000031 0.282626 8.7 1.1 882 1014MK19-09 640 0.053298 0.000586 0.002315 0.000027 0.282643 0.000043 0.282615 8.6 1.5 893 1029MK19-10 616 0.122879 0.002748 0.004022 0.000086 0.282690 0.000034 0.282643 9.0 1.2 866 982MK19-11 612 0.159709 0.004375 0.005080 0.000134 0.282641 0.000027 0.282583 6.8 1.0 970 1119MK19-12* 523 0.048532 0.001248 0.001797 0.000044 0.282701 0.000039 0.282683 8.4 1.4 797 950MK19-13c 619 0.098228 0.001320 0.002840 0.000045 0.282664 0.000035 0.282631 8.7 1.2 875 1006MK19-14c 619 0.062747 0.001638 0.002263 0.000052 0.282744 0.000038 0.282718 11.7 1.4 745 812MK19-15c 619 0.237606 0.005139 0.006938 0.000145 0.282669 0.000045 0.282589 7.2 1.6 979 1102MK19-16c 619 0.033618 0.000708 0.001304 0.000030 0.282675 0.000030 0.282659 9.7 1.1 824 943MK19-17c 619 0.046695 0.000488 0.001523 0.000016 0.282650 0.000023 0.282632 8.7 0.8 865 1005MK19-18c 619 0.051223 0.000683 0.002032 0.000024 0.282691 0.000029 0.282667 9.9 1.0 818 926MK19-19c 619 0.034006 0.000318 0.001505 0.000015 0.282631 0.000023 0.282613 8.0 0.8 891 1047

In situ Hf isotope analyses were carried out on the dated spots or in the same area using a Neptune MC-ICPMS at the Institute of Geology and Geophysics, Chinese Academy ofSciences in Beijing, China. Epsilon Hf isotope values were calculated with reference to the chondritic ratio at the age of every grain or at the time of crystallization (c), a decayconstant for 176Lu of 1.867 × 10−11 (Söderlund et al., 2004), and the average present-day CHUR value of 176Hf/177Hf (0.282772) and 176Lu/177Hf (0.0332) (Blichert-Toft andAlbaréde, 1997) were used. Single-stage Hf model ages (TDM) were calculated using the measured ratios, referred to a model depleted mantle with present-day 176Hf/177Hf of0 modec rains #

SUaHfwp4od1

f(ircfGotE

.28325 and 176Lu/177Hf of 0.0384 (Vervoort and Blichert-Toft, 1999). Two-stage Hf

ontinental crust (Griffin et al., 2002). Zircon grains >10% discordant (*); and bold g

tanford University and the SHRIMP II ion microprobe at Curtinniversity. Detailed techniques of the instrumental configurationsre described by Nelson (1997) and Williams (1998). In situ zirconf isotope analyses were carried on the dated sites (n = 129) and

ew undated sites (n = 27) using a Neptune MC-ICPMS, equippedith a 193-nm ArF laser, at the Institute of Geology and Geo-hysics, Chinese Academy of Sciences in Beijing. Spot sizes were0–50 �m with a laser repetition rate of 8 Hz at a laser powerf 100 mJ/pulse. Analytical techniques and data correction proce-ures are described in Wu et al. (2006). Interference of 176Lu on76Hf was corrected by measuring the intensity of the interference-ree 175Lu, using the recommended 176Lu/175Lu ratio of 0.02669DeBievre and Taylor, 1993) to calculate 176Lu/177Hf. Similarly, thesobaric interference of 176Yb on 176Hf was corrected by using aecommended 176Yb/172Yb ratio of 0.5886 (Chu et al., 2002) toalculate 176Hf/177Hf ratio. The analysis was performed using dif-erent standard references (supplementary material, Table A1). The



J-1 zircon standard yielded a weighted average 176Hf/177Hf ratiof 0.282021 ± 0.000005 (2�, n = 68). This value agrees well withhe recommended value of 0.282015 ± 19 (2�, n = 25) reported bylhlou et al. (2006). The Mud Tank zircon standard (supplementary

l ages (TDMc) are calculated assuming a mean 176Lu/177Hf value of 0.015 for average

s that have been dated and pass concordancy test.

material – Table A1) yielded a weighted average 176Hf/177Hf ratioof 0.282509 ± 0.000004 (2�, n = 58), in agreement with the valueof 0.282504 ± 0.000044 (2�, n = 158) reported in literature byWoodhead and Hergt (2005). The 91500 zircon standard have beenanalyzed twice at the starting of the session and yielded a weightedaverage 176Hf/177Hf ratio of 0.282317 ± 0.000018 (2�, n = 2). Thisvalue agrees well with the recommended value of 176Hf/177Hfratio of 0.282307 ± 0.000031 (Wu et al., 2006). The decay constantadopted for 176Lu was 1.867 × 10−11 yr−1 (Söderlund et al., 2004).Initial 176Hf/177Hf reported as �Hf(T) is calculated using a chondriticreservoir with 176Hf/177Hf = 0.282772 and 176Lu/177Hf = 0.0332(Blichert-Toft and Albaréde, 1997). Single-stage Hf model ages (Hf-TDM) were calculated using the measured 176Lu/177Hf of zirconrelative to a model depleted mantle with 176Hf/177Hf = 0.28325 and176Lu/177Hf = 0.0384 (Vervoort and Blichert-Toft, 1999), can onlygive a minimum age for the source material of a magma fromwhich the zircon crystallized. The two-stage Hf (crustal) model


ages (TDMc) were calculated which assume that the zircon’s par-

ent magma was produced from a volume of average continentalcrust (176Lu/177Hf = 0.015; Griffin et al., 2002) that was originallyderived from a depleted mantle source (Belousova et al., 2010).





CHUR

εHf(T

)

DM (Bodet and Scharer, 2000)

(a)Southern Israel arc-derivedmetasediments & rhyoliticdikes (Morag et al., 2011)

Archean upper crust growth line

for Lu /

Hf = 0.015

176177

0 1000 2000 3000 4000-50

-30

-10

10

30

50

W. Dabbah metavolcanics (n = 13)

W. Kareim metavolcanics (n = 41)

W. Dabbah metasediments (n= 20)

U-Pb zircon (Ma)

500 600 700 800 900-10

-5

0

5

10

15

20

25

30

U-Pb zircon (Ma)

DM (Bodet and Scharer, 2000)

(b)El-Shalul, Sinai and southern Israel alkaline& calc-alkaline plutonic rocks (Be’ eri-Shlevin et al., 2010; Ali et al., 2012a)

εH

f(T)

CHUR Humrat Mukbid granite (n = 18)

Humr Akarim granite (n = 25)

Fig. 3. Epsilon Hf(T) versus age plots: (a) <10% discordant zircons from the arc-metavolcanics and metasediments from Wadi Kareim and Wadi El-Dabbah, CentralEastern Desert (CED), Egypt and (b) <10% discordant zircons from the Humr Akarimand Humrat Mukbid post-collisional granites from the South Eastern Desert ofEgypt. Depleted mantle (DM) growth curve from Bodet and Scharer (2000). CHURis chondritic uniform reservoir (CHUR). The field for southern Israel arc-derivedmetasediments and rhyolitic dikes is from Morag et al. (2011). The field for the El-SI

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Supplementary data associated with this article can be found,n the online version, at http://dx.doi.org/10.1016/j.precamres.013.05.007.

To evaluate the magmatic sources of the post-collisional gran-tes and arc-volcanics, and the provenance of metasediments, 156ircon spots (49 in granites, 76 in metavolcanics and 31 in metased-ments) were analyzed for Lu/Hf isotopic composition. Zircons

ith U/Pb discordancy of <10% are considered to record the agef the initial magmatic event, whereas zircons with >10% dis-ordancy reflect significant Pb loss or metamorphic overgrowthCondie et al., 2005; Table 2), so these analyses were omittedrom further discussion. Metasediments 65%, agreed. For the gran-tes, 16 analyses are <10% discordant, 6 are discordant, and 27rains are undated; 16/22*100 = 73%. For the metavolcanics, 54rains are <10% discordant, and 22 are discordant; 54/76*100 = 71%.ge-corrected epsilon values (�Hf(T)) were calculated using theeasured 176Hf/177Hf and 176Lu/177Hf and the apparent U–Pb ages

btained from the same grain or the crystallization age of the mag-atic population if the zircon grain was not analyzed for U–Pb

ge (Ali et al., 2009b, 2012b). Ages reported in previous study


re 603 ± 9 Ma and 619 ± 8 Ma for the Humr Akarim granite (AK-) and Humrat Mukbid granite (MK-19), respectively (Ali et al.,012b). Ta

ble

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Fig. 4. Cathodoluminescence images of 31 representative zircon grains from metavolcanics, metasediments and post-collisional granites analyzed during this study: Z1–Z9typical Neoproterozoic, Paleoproterozoic and Archean igneous zircon grains from Wadi Kareim and Wadi El-Dabbah metavolcanic samples; Z10–Z19 Neoproterozoic, Paleo-proterozoic and Archean zircon grains from Wadi El-Dabbah metasedimentary samples D1 and D13; Z20–Z25 zircon grains from Humr Akarim post-collisonal granite sampleAK-6; and Z26-Z31 zircon grains from Humrat Mukbid post-collisonal granite sample MK-19. Location of ion-microprobe U–Pb age and Lu–Hf analysis spots are shown bywhite or black circles. U–Pb zircon ages (Ali et al., 2009a,b) and �Hf(T) values are shown. Scale is 100 �m.


IN PRESSG Model

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Fig. 5. (a) Plot of �Nd(T) versus U–Pb zircon age for the metavolcanics and post-collisional granites from previous studies (Ali et al., 2009a,b, 2012b). The referenceline for chondritic uniform reservoir (CHUR) and the depleted mantle evolutioncurves of DM are from DePaolo (1981) and Goldstein et al. (1984). The field of theArabian-Nubian Shield (ANS) juvenile crust is from Claesson et al. (1984), Zimmeret al. (1995), Hargrove et al. (2006b), Stoeser and Frost (2006), Moussa et al. (2008),Ali et al. (2010c), and Liégeois and Stern (2010) and (b) �Hf(T) versus whole-rock�Nd(T) zircon diagram. Data points include single zircon �Hf(T) from this study


0 K.A. Ali et al. / Precambria

. Hf isotope results

Results for 156 analyses are listed in Table 1. �Hf(T) for zir-ons that passed the concordancy test are plotted in Fig. 3a and. Table 2 summarizes the Hf results from this study and Nd resultsrom previous studies (Ali et al., 2009b, 2012b).

.1. Central Eastern Deser, Wadi El-Dabbah metasediments

Cathodoluminescence (CL) imaging shows a significant varia-ion in internal structure and morphology (Fig. 4) in the zirconsrom the metasediments. Some zircons show well-developed oscil-atory zoning (e.g., Z17) as expected for magmatic zircons (Föstert al., 2001; Söderlund et al., 2002; Corfu et al., 2003). A few zir-ons have xenocrystic cores (e.g., Z8, Z18), and some are roundednd show weak zoning or no zoning at all (e.g., Z19). On theHf(T)–age plot, zircons from the metasediments have �Hf(T) thataries between +10.2 and −13.6 (Table 1 and Fig. 3a). Single-stagef model ages (TDM) range from 994 Ma to 3292 Ma and two-

tage Hf model ages (TDMc) vary between 1143 Ma and 3683 Ma

Tables 1 and 2). This strongly suggests the source regions of Cen-ral Eastern Desert (CED) metasediments contained a significantmount of older crustal components.

.2. Central Eastern Desert metavolcanics

Zircons from metavolcanics are euhedral prismatic to roundedFig. 4). In CL images, they show variation in internal structure andoning ranging from homogeneous to well-developed (e.g., Z3, Z4).ome crystals show xenocrystic cores (e.g., Z9) and others showeak zoning or no zoning. These later grains are interpreted asetamorphic zircons formed during partial melting (Föster et al.,

001; Söderlund et al., 2002). On the �Hf(T)–age plot, the metavol-anic zircons show mainly negative epsilon values (64.8% negativealues and 35.2% positive values), with �Hf(T) between +23.5 and35 (Tables 1 and 2; Fig. 3a). Single-stage Hf model ages (TDM)

ange from 776 Ma to 3171 Ma and two-stage model ages (TDMc)

ary between 776 Ma and 3790 Ma (Tables 1 and 2). This indicateshat sources of the CED arc-metavolcanics contain older crustalomponents.

.3. Post-collisional granitic rocks

Zircon CL images from the post-collisional granites (Fig. 4) showell-developed oscillatory zoning (e.g., Z20, Z26), typical of mag-atic zircons (Corfu et al., 2003). On the �Hf(T)–age plot (Fig. 3b),

he post-collisional granitic zircons show positive �Hf(T) varyingrom +4.0 to +11.9 (Tables 1 and 2; Fig. 3b). They have a weighted

ean �Hf(T) of 7.97 ± 1, and yield an average single-stage Hf modelge (TDM) of 879 Ma and two-stage Hf model age (TDM

c) of 1049 MaTables 1 and 2). This suggests that granitic samples were derivedrom a juvenile source.

. Discussion

The results of the present study, when combined with availablesotopic data from previous studies (Ali et al., 2009b; Be’eri-Shlevint al., 2010; Morag et al., 2011; Ali et al., 2012a,b), reveal the possiblenvolvement of pre-Neoproterozoic crust in the formation of theNS Neoproterozoic juvenile crust.

Detrital and magmatic (including xenocrystic) zircons in the



etasediments and arc-metavolcanics show a wide range of �Hf(T),etween +10.2 to −13.6 and +24 to −35, respectively. The posi-ive values are lower than expected for depleted mantle and theegative values are higher than expected for average Archean

and whole-rock �Nd(T) from Ali et al. (2009a,b, 2012b). The field for �Nd(T)–�Hf(T)juvenile crust is from Katz et al. (2004), Vervoort and Blichert-Toft (1999), Be’eri-Shlevin et al. (2010), and Ali et al. (2012a).

upper crust (UC; Fig. 3a). This allows the possibility of assimila-tion of older crust, but is inconsistent with the narrow range ofpositive initial epsilon Nd (�Nd(T) = +5.1 to +8.9) values for CED arc-metavolcanics (Ali et al., 2009b). Nevertheless, the �Nd(T) values fornearly half of the samples analyzed are lower than that expected fordepleted mantle at ∼750 Ma (Fig. 5), which suggests involvementof some pre-Neoproterozoic continental crust in the formation ofANS arc-metavolcanic magmas. Similar evidence of assimilation isalso detected in the abundance of pre-Neoproterozoic U–Pb zir-con ages common in especially mafic ANS igneous rocks and inmetasediments (Hargrove et al., 2006a,b; Be’eri-Shlevin et al., 2009;Ali et al., 2009b,a, 2010b,c; Stern et al., 2010). However, these rockshave mantle-like Nd isotopic compositions (Stern, 2002). This maybe explained either by inheritance from a contaminated mantlesource region or due to incorporation of minor amounts of sedimentduring magma generation or emplacement (Ali et al., 2009b; Sternet al., 2010). This later interpretation is supported by the fact that


most pre-Neoproterozoic zircons with negative �Hf(T) are foundin volcano-sedimentary rocks, consistent with previous studies(Be’eri-Shlevin et al., 2010; Morag et al., 2011; Fig. 3a and b). Onepossibility is that zircons may have been removed from the upper







Fig. 6. (a) Histogram of Hf model ages (Hf-TDMc) for single zircons from the metavol-

canics and metasediments from the CED of Egypt analyzed during this study. Modelages were calculated assuming a mean 176Lu/177Hf value of 0.015 for average con-tinental crust (Griffin et al., 2002) and (b) histogram of U–Pb single-zircon agesshowing the distribution of U–Pb zircon ages in CED metavolcanics and metased-iments (Ali et al., 2009a,b) and for the pre-Neoproterzoic rocks from surroundingregions in western Egypt, northern Sudan, Saudi Arabia, Yemen, and the Saharametacraton (modified after Ali et al., 2010b).

U-P

b ag

e (M

a)

T

= t

DMT

=

t + 30

0

DM

T

= t

+ 900

DM

(a)

t = U-Pb zircon ageU-Pb single zircons < 10% discordant

500 1000 1500 2000 2500 3000 3500 4000500

1000

1500

2000

2500

3000

Hf -T (Ma)DMc

W. Dabbah metavolcanics (n = 13)

W. Kareim metavolcanics (n = 41)

W. Dabbah metasediments (n = 20)

Mean Hf-T c = 2312 MaDM

Pre-Neoproterozoic crust

Juvenile crust

Cont

amin

ated

U-P

b ag

e (M

a)

Mean Hf-T c = 1049 MaDM

Hf -T (Ma)DMc

500 1000 1500 2000 2500500

600

700

800

900

1000

1100

1200

1300

14001500

Pre-Neoproterozoic crust

Cont

amin

ated

Humrat Mukbid granite = (n = 18)

Humr Akarim granite (n = 25)

(b)

Juvenile crustT

=

tD

M

T

= t

+ 30

0

DM

T

= t

+ 90

0

DM

t = U-Pb zircon ageJuvenile crustThis study, n = 43

U-Pb single zircons < 10% discordantand undated zircons

Fig. 7. (a) Plots of U–Pb zircon ages versus Hf model ages (Hf-TDMc) (modified after

Hargrove et al., 2006b) for single zircons analyzed during this study from (a) themetavolcanics and metasediments from the CED of Egypt and (b) from the HumrAkarim and Humrat Mukbid post-collisional granites from the South Eastern Desertof Egypt. Model ages were calculated assuming a mean 176Lu/177Hf value of 0.015 foraverage continental crust (Griffin et al., 2002). Data yielding Hf-TDM

c = t (U–Pb zir-con age) or Hf-TDM

c < t + 300 are considered to come from juvenile oceanic crust,whereas those with t + 300 < Hf-TDM

c < t + 900 are considered from juvenile crustcontaminated by pre-Neoproterozoic crust, and those with Hf-TDM

c > t + 900 arefrom evolved (continental) pre-Neoproterozoic crust.

Data for U–Pb single zircon ages (<10% discordant) are from Ali et al. (2009a,b,2012b).

plate by process of subduction erosion (Von Huene and Scholl,1991), whereby zircon survived processing through the subductionzone to become incorporated in subduction-related magmas.

Post-collisional granite zircons show a relatively narrow rangeof �Hf(T), between +11.9 and +4 (Table 1). These values are simi-lar to those expected if generated from contemporaneous depletedmantle (Fig. 3b), consistent with the �Nd(T) values (+7.5 to +3.4;


Fig. 5) reported by Ali et al. (2012b). These results are also consistentwith previous studies of post-collisional granites: (1) in Sinai andsouthern Israel (�Nd(T) = +5.6 to +1.1; �Hf(T) = +5.5 to +13.9; Fig. 3b;


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e’eri-Shlevin et al., 2010) and (2) in the El-Shalul granitic dome,ED of Egypt (�Nd(T) = +6.6 to +7.5; �Hf(T) = +6.1 to +12; Fig. 3b;li et al., 2012a). This supports the idea that post-collisional gran-

te magmas incorporated slightly older juvenile crust, which waserived originally from a depleted mantle source (Fig. 5; Ali et al.,012b).

Single-stage Hf model ages (TDM) provide minimum estimatesor crustal formation (e.g., Kemp et al., 2006). The Hf-TDM ages cal-ulated for CED arc-metavolcanic rocks range between 0.78 and.2 Ga, whereas two-stage Hf model ages (TDM

c) calculated withrustal precursors of intermediate composition (Table 2) yield agesetween 0.78 and 3.8 Ga. The TDM

c ages (Fig. 6a) are consistentith the distribution of U–Pb zircon ages (Fig. 6b) for the metavol-

anics from the same areas (Ali et al., 2009b), which may reflecthe involvement of pre-Neoproterozoic material in the formationf the ANS arc-metavolcanics (Fig. 7a).

Hf depleted mantle model ages for the ∼620 Ma post-collisionalranites are between 0.74 and 1.1 Ga (average = 0.90 Ga) for TDMnd for TDM

c are between 0.81 and 1.3 Ga (average = 1.1 Ga), ingreement with the Nd-TDM (Table 2; model of Goldstein et al.,984) and with accepted formation of the ANS (Stern, 1994; Be’eri-hlevin et al., 2010). This indicates a negligible contribution fromlder continental crust and derivation by melting of a juvenileource (Fig. 7b and Table 1). Note the correspondence of old-st Hf model ages with oldest U–Pb ages, but that a significantontribution from older crust or sediments is evident in some Neo-roterozoic zircons. Overall, the new Hf isotope data presented inhis study (Tables 1 and 2; Figs. 3 and 7) reveal that early evolutionf the ANS involved recycling of some older materials, (Hargrovet al., 2006a,b; Ali et al., 2009b, 2010a,b,c; Be’eri-Shlevin et al.,010; Morag et al., 2011). This contribution appears to diminishith time, disappearing completely when the post-collision gran-

tes were emplaced at ∼620 Ma.In summary, we can explain our results by the fact that dur-

ng arc-magmatism, subduction progressively removed ancientower crust and subcontinental lithospheric mantle. This allows Hfo shift toward progressively more radiogenic isotopic composi-ion during the post-collisional stage, whereby zircon �Hf valueshanged from negative to positive (Collins et al., 2011), reflect-ng continuing addition of juvenile crust derived largely from thenderlying convecting mantle wedge. Therefore, zircons from arcetavolcano-sedimentary rocks define a broad data band (Collins

t al., 2011). However, the post-collisional processes associatedith delamination, orogenic collapse or lithospheric extensionhich likely melt the underlying arc juvenile crust, therefore driv-

ng zircon �Hf to more positive values (Fig. 3b; Collins et al., 2011).

. Conclusions

LA-ICP-MS Hf-isotope data for zircons from the Neoprotero-oic metasediments and arc-metavolcanics of the Eastern Desertf Egypt reveal a significant proportion with negative �Hf(T),ndicating cryptic and somewhat enigmatic involvement of pre-eoproterozoic materials in the formation of otherwise juvenileNS crust. This is supported by the Hf-TDM

c ages calculated for CEDrc-metavolcanic rocks which range between 0.78 and 3.8 Ga, and–Pb zircon ages reported previously (Ali et al., 2009b).

Zircons from ∼620 Ma post-collisional granites at Humr Akarimnd Humrat Mukbid all have positive �Hf(T) (+4.4 to +11.9) andNd(T) (+3.4 to +7.5), and plot as expected for evolving from juve-ile crust. They formed mostly from mantle derived-magmas, but



ay be contaminated by minor amount of older crustal materialss indicated from the ∼700 Ma zircons (Ali et al., 2012b), the wideange of �Hf(T) and �Nd(T) and the Hf-TDM

c ages between 0.81 and.3 Ga.

PRESSarch xxx (2013) xxx– xxx

Acknowledgments

We dedicate this study to the memory of Dr. Ewais Moussa whoworked extensively in the ED, and provided KAA with some keyED samples that were integrated in this study. He passed away inOctober 2, 2012 at age of 50. This work was supported by NSF-OISE grant 0821257. The SHRIMP II facility in Perth is operatedjointly by Curtin University, the University of Western Australia andthe Geological Survey of Western Australia, with support from theAustralian Research Council. The authors would like to thank theInstitute of Geology and Geophysics, Chinese Academy of Sciences,Beijing for performing the Hf-isotope analyses. We sincerely thanktwo anonymous reviewers for their constructive comments andsuggestions that greatly helped to improve the manuscript. Greatthanks go to Editor Prof. Victoria Pease for handling the manuscript.This is UTD Geosciences contribution number #1238 and TIGeRpublication # 463. This is a JEBEL contribution.

References

Abd El-Naby, H., Frisch, W., Hegner, E., 2000. Evolution of the Pan-African WadiHaimur metamorphic sole, Eastern Desert, Egypt. Journal of Metamorphic Geol-ogy 18, 639–651.

Abdelsalam, M.G., Liégeois, J.P., Stern, R.J., 2002. The Saharan metacraton. Journal ofAfrican Earth Sciences 34, 119–136.

Abdelsalam, M.G., Stern, R.J., Copeland, P., Elfaki, E.M., Elhur, B., Ibrahim, F.M., 1998.The Neoproterozic Keraf suture in NE Sudan: sinistral transpression along theeastern margin of West Gondwana. Journal of African Geology 106, 133–148.

Agar, R.A., Stacey, J.S., Whitehouse, M.J., 1992. Evolution of the southern Afif terrane– a geochronologic study. Saudi Arabian Deputy Ministry for Mineral ResourceOpen File Report DGMR-OF-10-15, p. 41.

Ali, B.H., Wilde, S.A., Gaber, M.M.A., 2009a. Granitoid evolution in Sinai, Egypt, basedon precise SHRIMP U–Pb zircon geochronology. Gondwana Research 15, 38–48.

Ali, K.A., Andresen, A., Stern, R.J., Manton, W.I., Omar, S.A., Maurice, A.E., 2012a.U–Pb zircon and Sr-Nd-Hf isotopic evidence for a juvenile origin of the c634 Ma El-Shalul Granite, Central Eastern Desert, Egypt. Geological Magazine149, 783–797.

Ali, K.A., Azer, M.K., Gahlan, H.A., Wilde, S.A., Samuel, M.D., Stern, R.J., 2010a. Age con-straints on the formation and emplacement of Neoproterozoic ophiolites alongthe Allaqi-Heiani Suture, South Eastern Desert of Egypt. Gondwana Research 18,583–595.

Ali, K.A., Moghazi, A.M., Maurice, A.E., Omar, S.A., Wang, Q., Wilde, S.A., Moussa, E.M.,Manton, W.I., Stern, R.J., 2012b. Composition, age, and origin of the ∼620 MaHumr Akarim and Humrat Mukbid A-Type granites: no evidence for pre-Neoproterozoic basement in the Eastern Desert, Egypt. International Journal ofEarth Sciences 101, 1705–1722, http://dx.doi.org/10.1007/s00531-012-0759-2.

Ali, K.A., Stern, R.J., Manton, W.I., Johnson, P.R., Mukherjee, S.K., 2010b. Neopro-terozoic diamictite in the Eastern Desert of Egypt and Northern Saudi Arabia:evidence of ∼750 Ma glaciation in the Arabian-Nubian Shield International Jour-nal of Earth Sciences 99, 705–726.

Ali, K.A., Stern, R.J., Manton, W.I., Kimura, J-I., Khamees, H.A., 2009b. Geochemistry,Nd isotopes and U–Pb SHRIMP dating of Neoproterozoic volcanic rocks from theCentral Eastern Desert of Egypt: new insights into the ∼750 Ma crust-formingevent. Precambrian Research 171, 1–22.

Ali, K.A., Stern, R.J., Manton, W.I., Kimura, J.-I., Whitehouse, M.J., Mukherjee, S.K.,Johnson, P.R., Griffin, W.R., 2010c. Geochemical, U–Pb zircon, and Nd isotopeinvestigations of the Neoproterozoic Ghawjah Metavolcanic rocks, Northwest-ern Saudi Arabia. Lithos 120, 379–393.

Andersen, T., Griffin, W.L., Pearson, N.J., 2002. Crustal evolution in the SWpart of the Baltic Shield: the Hf isotope evidence. Journal of Petrology 43,1725–1747.

Andresen, A., El-Rus, M.A., Myhre, P.I., Boghdady, G.Y., Corfu, F., 2009. U–Pb TIMSage constraints on the evolution of the Neoproterozoic Meatiq Gneiss Dome,Eastern Desert, Egypt. International Journal of Earth Sciences 98, 481–497.

Avigad, D., Gvirtzman, Z., 2009. Late Neoproterozoic rise and fall of the northernArabian-Nubian Shield: the role of lithospheric mantle delamination and sub-sequent thermal subsidence. Tectonophysics 477, 217–228.

Be’eri-Shlevin, Y., Katzir, Y., Whitehouse, M., 2009. Post-collisional tectono-magmatic evolution in the northern Arabian-Nubian Shield (ANS): timeconstraints from ion probe U–Pb dating of zircon. Journal of Geological Societyof London 166, 71–85.

Be’eri-Shlevin, Y., Katzir, Y., Blichert-Toft, J., Kleinhanns, I.C., Whitehouse, M., 2010.Nd–Sr–Hf–O isotope provinciality in northernmost Arabian-Nubian Shield:


implication for crustal evolution. Contributions to Mineralogy and Petrology160, 181–201.

Be’eri-Shlevin, Y., Eyal, M., Eyal, Y., Whitehouse, M.J., Litvinovsky, B., 2012. The Sa’alvolcano-sedimentary complex (Sinai, Egypt), a latest Mesoproterozoic volcanicarc in the northern Arabian Nubian Shield. Geology 40, 403–406.


http://refhub.elsevier.com/S0301-9268(13)00160-5/sbref0005


























































































































































dx.doi.org/10.1007/s00531-012-0759-2






















































































































































































































































ING Model

P

n Rese

B

B

B

B

B

C

C

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C

C

D

D

D

D

D

D

E

E

F

F

G

G

G

G

H

H

H


K.A. Ali et al. / Precambria

elousova, E., Kostitsyn, Y.A., Griffin, W.L., Begg, G.C., O’Reilly, S.Y., Pearson, N.J.,2010. The growth of the continental crust: constraints from zircon Hf-isotopedata. Lithos 119, 457–466.

lichert-Toft, J., Albaréde, F., 1997. The Lu–Hf geochemistry of chondrites and theevolution of the mantle–crust system. Earth and Planetary Science Letters 148,243–258.

lichert-Toft, J., Albaréde, F., Rosing, M., Frei, R., Bridgwater, D., 1999. The Nd andHf isotopic evolution of the mantle through the Archean. Results from the Isuasupracrustals, West Greenlamd, and from the Birimian terranes of West Africa.Geochimica et Cosmochimica Acta 63, 3901–3914.

odet, F., Scharer, U., 2000. Evolution of the SE-Asian continent from U–Pb and Hfisotopes in single grains of zircon and baddeleyite from large River. Geochimicaet Cosmochimica Acta 64, 2067–2091.

regar, M., Bauernhofer, A., Pelz, K., Kloetzli, U., Fritz, H., Neumayr, P., 2002. A lateNeoproterozoic magmatic core complex in the Eastern Desert of Egypt: emplace-ment of granitoids in a wrench-tectonic setting. Precambrian Research 118,59–82.

hu, N.C., Taylor, R.N., Chavagnac, V., Nesbitt, R.W., Boella, R.M., Milton, J.A., German,C.R., Bayon, G., Burton, K., 2002. Hf isotope ratio analysis using multi-collectorinductively coupled plasma mass spectrometer: an evaluation of isobaric inter-ference corrections. Journal of Analytical Atomic Spectrometry 17, 1567–1574.

laesson, S., Pallister, J.S., Tatsumoto, M., 1984. Samarium-neodymium data on twolate Proterozoic ophiolites of Saudi Arabia and implications for crustal and man-tle evolution. Contributions to Mineralogy and Petrology 85, 244–252.

ollins, A.S., Pisarekvsky, S.A., 2005. Amalgamating eastern Gondwana: the evolu-tion of the Circum-Indian Orogens. Earth Science Reviews 71, 229–270.

ollins, W.J., Belousova, E.A., Kemp, A.I.S., Murphy, B.J., 2011. Two contrastingPhanerozoic orogenic systems revealed by hafnium isotope data. Nature Geo-science 4, 333–337.

ondie, K.C., Beyer, E., Belousova, E., Griffin, W.L., O’Reilly, S.Y., 2005. U–Pb iso-topic ages and Hf isotopic composition of single zircons: the search for juvenilePrecambrian continental crust. Precambrian Research 139, 42–100.

orfu, F., Hanchar, J.M., Hoskin, P.W., Kinny, P., 2003. Atlas of zircon textures. Reviewsin Mineralogy and Geochemistry 53, 469–500.

eBievre, P., Taylor, P.D.P., 1993. Table of the isotopic composition of the ele-ments. International Journal of Mass Spectrometry and Ion Processes 123,149–166.

ePaolo, D.J., 1981. Neodymium isotopes in the Colorado Front Range andcrust–mantle evolution in the Proterozoic. Nature 291, 193–196.

ePaolo, D.J., Linn, A.M., Schubert, G., 1991. The continental crustal age distribu-tion. Methods of determining mantle separation ages from Sm–Nd isotopic dataapplication to the Southwestern United States. Journal of Geophysical Research96, 2071–2088.

ePaolo, D.J., Perry, F.V., Baldridge, W.S., 1992. Crustal vs. mantle sources of graniticmagmas: a two parameter model based on Nd isotopic studies. Royal Society ofEdinburgh Transactions, Earth Sciences 83, 439–446.

ickin, A.P., 2005. Radiogenic Isotope Geology. Press Syndicate of the University ofCambridge, pp. 492 pp.

ixon, T.H., Golombek, M.P., 1988. Late Precambrian crustal accretion rates in North-east Africa and Arabia. Geology 16, 991–994.

lhlou, S., Belousova, e., Griffin, W.L., Pearson, N.J., O‘reilly, S.Y., 2006. Trace elementand isotopic composition of GJ-red zircon standard by laser ablation. Geochimicaet Cosmochimica Acta 70, A158, http://dx.doi.org/10.1016/j.gca.2006.06.1383.

yal, M., Litvinovsky, B., Jahn, B., Zanvilevich, A., Katzir, Y., 2010. Origin and evolutionof post-collisional magmatism: coeval Neoproterozoic calc-alkaline and alkalinesuites of the Sinai Peninsula. Chemical Geology 269, 153–179.

öster, D.A., Schafer, C., Fanning, C.M., Hyndman, D.W., 2001. Relatioships betweencrustal partial melting, plutonism, orogeny, and exhumation: Idaho-Bitterrootbatholith. Tectonophysics 342, 313–350.

ritz, H., Abdelsalam, M., Ali, K., Bingen, B., Collins, A.S., Fowler, A.R., Ghebreab, W.,Hauzenberger, C.A., Johnson, P., Kusky, T., Macey, P., Muhongo, S., Stern, R.J.,Viola, G., 2013. Orogen styles in the East African Orogens: a review of the Neo-proterozoic to Cambrian tectonic evolution. Journal of African Earth Sciences, inpress.

eological Map of Egypt, 1987. Scale 1:500,000. In: Klitsch, E., List, F.K., Pöhlmann,G. (Compil.), Conoco Coal and the Egyptian General Petroleum Corporation.Technische Fachhochschule, Berlin.

enna, A., Nehlig, P., Le Goff, E., Gguerrot Cc Shanti, M., 2002. Proterozoic tectonismof the Arabian Shield. Precambrian Research 117, 21–40.

oldstein, S.L., O‘Nions, R.K., Hamilton, P.J., 1984. A Sm–Nd isotopic study of atmo-spheric dusts and particulates from major river systems. Earth and PlanetaryScience Letters 70, 221–236.

riffin, W.L., Wang, X., Jackson, S.E., Pearson, N.J., O’Reilly, S.Y., Xu, X., Zhou, X., 2002.Zircons chemistry and magma genesis in SE China: in situ analysis of Hf isotopes,Pingtan and Tonglu igneous complexes. Lithos 61, 237–269.

argrove, U.S., Stern, R.J., Griffin, W.R., Johnson, P.R., Abdelsalam, M.G., 2006a. FromIsland Arc to Craton: timescales of crustal formation along the NeoproterozoicBi’r Umq Suture zone, Kingdom of Saudi Arabia. In: Saudi Geological SurveyTechnical Report SGS-TR-2006-6, p. 69.

argrove, U.S., Stern, R.J., Kimura, J.I., Manton, W.I., Johnson, P.R., 2006b. Howjuvenile is the Arabian-Nubian Shield? Evidence from Nd isotopes and pre-



Neoproterozoic inherited zircon in the Bi’r Umq suture zone, Saudi Arabia. Earthand Planetary Science Letters 252, 308–326.

assanen, M.A., Harraz, H.Z., 1996. Geochemistry and Sr- and Nd-isotopic study onrare-metal-bearing granitic rocks, central Eastern Desert, Egypt. PrecambrianResearch 80, 1–22.

PRESSarch xxx (2013) xxx– xxx 13

Huang, J., Zheng, Y.-F., Zhao, Z.-F., Wu, Y.-B., Zhou, J.-B., Liu, X., 2006. Melting ofsubducted continent: element and isotopic evidence for a genetic relationshipbetween Neoproterozoic and Mesozoic granitoids in the Sulu orogen. ChemicalGeology 229, 227–256.

Johnson, P.R., Andresen, A., Collins, A.S., Fowler, A.R., Fritz, H., Ghebrab, W., Kusky,T., Stern, R.J., 2011. Late Cryogenian-Ediacaran history of the Arabian-NubianShield: a review of depositional, plutonic, structural, and tectonic event in theclosing stages of the northern East African Orogen. Journal of African EarthSciences 61, 167–232.

Johnson, P.R., Woldehaimanot, B., 2003. Development of the Arabian-Nubian Shield:perspectives on accretion and deformation in the northern East African Orogenand the assembly of Gondwana. In: Yoshida, M., Dasgupta, S., Windley, B. (Eds.),Proterozoic East Gondwana: Supercontinent Assembly and Breakup. GeologicalSociety of London, Special Publications 206, pp. 289–325.

Katz, O., Beyth, M., Miller, N., Stern, R.J., Avigad, D., Basu, A., Anbar, A., 2004. A lateNeoproterozoic (630 Ma) high-magnesium andesite suite from southern Israel:implication for the consolidation of Gondwanaland. Earth and Planetary ScienceLetters 218, 275–290.

Kemp, A.I.S., Hawkesworth, C.J., Paterson, B.A., Kinny, P.D., 2006. Episodic growthof the Gondwana supercontinent from hafnium and oxygen isotopes in zircon.Nature 439, 580–583.

Kemp, A.I.S., Hawkesworth, C.J., Foster, G.L., Paterson, B.A., Woodhead, J.D., Hergt,J.M., Gray, C.M., Whitehouse, M.J., 2007. Magmatic and crustal differenti-ation history of granitic rocks from Hf–O isotopes in zircon. Science 315,980–983.

Kennedy, A., Johnson, P.R., Kattan, F.H., 2004. SHRIMP geochronology in the northernArabian Shield. Part I: Data acquisition. Saudi Geological Survey Open File Report,SGS-OF-2004-11.

Kröner, A., 1985. Ophiolites and the evolution of tectonic boundaries in the late Pro-terozoic Arabian-Nubian Shield of northeastern Africa and Arabia. PrecambrianResearch 27, 277–300.

Kröner, A., Sassi, F.P., 1996. Evolution of the northern Somali basement: new con-straints from zircon ages. Journal of African Earth Sciences 22, 1–15.

Kröner, A., Greiling, R., Reischmann, T., Hussein, I.M., Stern, R.J., Kruger, J., Duur, S.,Zimmer, M., 1987. Pan-African crustal evolution in the Nubian segment of North-east Africa. In: Kröner, A. (Ed.), Proterozoic Lithosphere Evolution. AmericanGeophysical Union, Washington, DC, pp. 235–257.

Kröner, A., Todt, W., Hussein, I.M., Mansour, M., Rashwan, A.A., 1992. Dating of lateProterozoic ophiolites in Egypt and the Sudan using the single zircon evapora-tion technique. Precambrian Research 59, 15–32.

Küster, D., Liégeois, J.P., Matukov, D., Sergeev, S., Lucassen, F., 2008. Zircongeochronology and Sr, Nd, Pb isotope geochemistry of granitoids from BayudaDesert and Sabaloka (Sudan): Evidence for a Bayudian event (920–900 Ma) pre-ceding the Pan-African orogenic cycle (860–590 Ma) at the eastern boundary ofthe Saharan Metacraton. Precambrian Research 164, 16–39.

Liégeois, J.P., Stern, R.J., 2010. Sr–Nd isotopes and geochemistry of granite-gneisscomplexes from the Meatiq and Hafafit domes, Eastern Desert, Egypt: no evi-dence for pre-Neoproterozoic crust. International Journal of Earth Sciences 57,31–40.

Loizenbauer, J., Wallbrecher, E., Fritz, H., Neumayr, P., Khudeir, A.A., Kloetzli, U., 2001.Structural geology, simple zircon ages and fluid inclusion studies of the Meatiqmetamorphic core complex: implications for Neoproterozoic tectonics in theEastern Desert of Egypt. Precambrian Research 110, 357–383.

Lundmark, A.M., Andresen, A., Hassan, M.A., Augland, L.E., Abu El-Rus, M.A., Bogh-dady, G.Y., 2012. Repeated magmatic pulses in the East African Orogen of CentralEastern Desert, Egypt: an old idea supported by new evidence. GondwanaResearch 22, 227–237.

Moghazi, A.M., Ali, K.A., Simon, W.A., Zhou, Q., Andersen, T., Andresen, A., AbuEl-Enen, M., Stern, R.J., 2012. Geochemistry, geochronology, and Sr–Nd iso-topes of the Late Neoproterozoic Wadi Kid volcano-sedimentary rocks, SouthernSinai, Egypt: implications for tectonic setting and crustal evolution. Lithos 154,147–165, doi:org/10.1016/j.lithos.2012.07.003.

Moghazi, A.M., Andersen, T., Oweiss, G.A., El Bouseily, A.M., 1998. Geochemical andSr–Nd–Pb isotopic data bearing on the origin of Pan-African granitoids in theKid area, southeast Sinai, Egypt. Journal of the Geological Society of London 155,697–710.

Morag, N., Avigad, D., Gerdes, A., Belousova, E., Harlavan, Y., 2011. Crustal evolutionand recycling in the northern Arabian-Nubian Shield: new perspectives fromzircon Lu–Hf and U–Pb systematics. Precambrian Research 186, 101–116.

Moussa, E.M.M., Stern, R.J., Manton, W.I., Ali, K.A., 2008. SHRIMP zircon datingand Sm/Nd isotopic investigations of Neoproterozoic granitoids, Eastern Desert,Egypt. Precambrian Research 160, 341–356.

Nelson, D.R., 1997. Complication of SHRIMP U–Pb Zircon Geochronology Data, 1996:Geological Survey of Western Australia, Record 1997/2, 189 pp.

Patchett, P.J., Kouvo, O., Hedge, C.E., Tastumoto, M., 1981. Evolution of continen-tal crust and mantle heterogenity: evidence from Hf isotopes. Contributions toMineralogy and Petrology 78, 279–297.

Saleh, G.M., Dawood, Y.H., Abd El-Naby, H.H., 2002. Petrological and geochemicalconstraints on the origin of the granitoid suite of the Homret Mikpid area, southEastern Desert, Egypt. Journal of Mineralogical and Petrological Sciences 97,47–58.


Scherer, E.E., Camerson, K.L., Blichert-Toft, J., 2000. Lu–Hf garnet geochronology:closure temperature relative to the Sm–Nd system and the effect of trace mineralinclusions. Geochimica et Cosmochimica Acta 64, 3413–3422.

Scherer, E.E., Munker, C., Mezger, K., 2001. Calibration of the lutetium–hafniumclock. Science 293, 683–687.






































































































































































































































































































































































































dx.doi.org/10.1016/j.gca.2006.06.1383































































































































































































































































































































































































































































































































































































































































































































































































































































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öderlund, U., Möller, C., Andersson, J., Johansson, L., Whitehouse, M., 2002. Zircongeochronology in polymetamorhic gneisses in the Sveconorwegian orogen. SWSweden: ion microprobe evidence for 1.46–1.42 and 0.98–0.96 Ga reworking.Precambrian Research 113, 193–225.

öderlund, U., Patchett, P.J., Vervoort, J.D., Isachsen, C.E., 2004. The 186Lu decayconstant determined by Lu–Hf and U–Pb isotope systematics of Precambrianmafic intrusions. Earth and Planetary Science Letters 219, 311–324.

tacey, J.S., Hedge, C.E., 1984. Geochronologic and isotopic evidence for early Pro-terozoic crust in the eastern Arabian Shield. Geology 12 (5), 310–313.

tern, R.J., 1981. Petrogenesis and tectonic setting of Late Precambrian ensimaticvolcanic rocks, Central Eastern Desert of Egypt. Precambrian Research 16,197–232.

tern, R.J., 1994. Arc assembly and continental collision in the Neoproterozoic EastAfrican Orogen: Implications for the consolidation of Gondwanaland. AnnualReviews of Earth and Planetary Science 22, 319–351.

tern, R.J., 2002. Crustal evolution in the East African Orogen: a Neodymium isotopicperspective. Journal of African Earth Sciences 34, 109–117.

tern, R.J., 2008. Neoproterozoic crustal growth: the solid Earth system during acritical episode of Earth history. Gondwana Research 14, 33–50.

tern, R.J., Ali, K.A., Liegeois, J.P., Johnson, P.R., Kozdroj, W., Kattan, F.H., 2010.Distribution and significance of pre-Neoproterozoic zircons in juvenile Neo-proterozoic igneous rocks of the Arabian-Nubian Shield. American Journal ofScience 310, 791–811.

tern, R.J., Avigad, D., Miller, N.R., Beyth, M., 2006. Evidence for the snowball earthhypothesis in the Arabian-Nubian Shield and the East African Orogen. Journal ofAfrican Earth Sciences 44, 1–20.

tern, R.J., Johnson, P.R., 2010. Continental lithosphere of the Arabian plate: ageologic, petrologic, and geophysical synthesis. Earth Science Reviews 101,29–67.

tern, R.J., Kröner, A., Bender, R., Reischmann, T., Dawoud, A.S., 1994. Precambrianbasement around Wadi Halfa, Sudan: a new perspective on the evolution of theEast Saharan Craton. Geologische Rundschau 83, 564–577.

toeser, D.B., Camp, E., 1985. Pan-African microplate accretion of the Arabian Shield.Geological Society of America Bulletin 96, 817–826.

toeser, D.B., Frost, C., 2006. Nd, Pb, Sr, and O isotopic characterization of SaudiArabian Shield terranes. Chemical Geology 226, 163–188.

toeser, D.B., Whitehouse, M.J., Stacey, J.S., 2001. The Khida Terrane-Geology of Pale-oproterozoic Rock in the Muhayil Area, Eastern Arabian Shield, Saudi Arabia.Gondwana Research 4, 192–194.

ultan, M., Tucker, R.D., El-Alfy, Z., Attia, R., Ragab, A.G., 1994. U–Pb (zircon) ages for



the gneissic terrane west of the Nile, southern Egypt. Geologische Rundschau83, 514–522.

ultan, M., Chamberlain, K.R., Bowring, S.A., Arvidson, R.E., Abuzied, H., El Kaliouby,B., 1990. Geochronologic and isotopic evidence for involvement of pre-Pan-African crust in the Nubian Shield, Egypt. Geology 18, 761–764.

PRESSarch xxx (2013) xxx– xxx

Vervoort, J.D., Blichert-Toft, J., 1999. Evolution of the depleted mantle: Hf isotopeevidence from juvenile rocks through time. Geochimica et Cosmochimica Acta63, 533–556.

Vervoort, J.D., Patchett, P.J., Gehrels, G.E., Nutman, A.P., 1996. Constraints on earlyearth differentiation from hafnium and neodymium isotopes. Nature 379,624–627.

Von Huene, R., Scholl, D.W., 1991. Observations at convergent margins concerningsediment subduction, subduction erosion and the growth of continental crust.Reviews of Geophysics 29, 279–316.

Walraven, F., Rumvegeri, B.T., 1993. Implications of whole-rock Pb–Pb and zirconevaporation dates for the early metamorphic history of the Kasai craton, South-ern Zaire. Journal of African Earth Sciences 16, 395–404.

Watson, E.B., 1996. Dissolution, growth and survival of zircons during crustal fusion:kinetic principles, geological models and implications for isotopic inheritance.Geological Society of America, Special Paper 315, 43–56.

Watson, E.B., Cherniak, D.J., 1997. Oxygen diffusion in zircon. Earth and PlanetaryScience Letters 148, 527–544.

Whitehouse, M.J., Windley, B.F., Ba-Bttat, M.A., Fanning, C.M., Rex, D.C., 1998.Crustal evolution and terrane correlation in the eastern Arabian Shield, Yemen:geochronological constraints. Journal of the Geological Society of London 155,281–295.

Whitehouse, M.J., Windley, B.F., Stoeser, D.B., Al-Khirbash, S., Ba-Bttat, M.A., Haider,A., 2001. Precambrian basement character of Yemen and correlations with SaudiArabia and Somalia. Precambrian Research 105, 357–369.

Williams, I.S., 1998. U–Th–Pb geochronology by ion microprobe. Reviews in Eco-nomic Geology 7, 1–35.

Windley, B.F., Whitehouse, M.J., Ba-Bttat, M.A.O., 1996. Early Precambrian gneissterranes and Panafrican island arcs in Yemen: crustal accretion of the easternArabian Shield. Geology 24 (2), 131–134.

Woodhead, J.D., Hergt, J.M., 2005. Preliminary appraisal of seven natural zirconreference materials for in-situ Hf isotope determination. Geostandards and Geo-analytical Research 29, 183–195.

Wu, F.Y., Yang, Y.H., Xie, L.W., Yang, J.H., Xu, P., 2006. Hf isotopic compositions ofthe standard zircons and baddeleyites used in U–Pb geochronology. ChemicalGeology 234, 105–126.

Zhao, X.F., Zhou, M.F., Li, J.W., Wu, F.Y., 2008. Association of NeoproterozoicA- and I-type granites in South China: Implications for generation of A-type granites in a subduction-related environment. Chemical Geology 257,1–15.

Zheng, J.P., Griffin, W.L., O’Reilly, S.Y., Zhang, M., Pearson, N.J., Pan, Y.M., 2006.


Widespread Archean basement beneath the Yangtze Craton. Geology 34,417–420.

Zimmer, M., Kröner, A., Jochum, K.P., Reischmann, T., Todt, W., 1995. The GabalGerf complex: a Precambrian N-MORB ophiolite in the Nubian Shield, NE Africa.Chemical Geology 123, 29–51.































































































































































































































































































































































































































































































































































































































































































Hf isotopic composition of single zircons from Neoproterozoic arc volcanics and post-collision granites, Eastern Desert of Egypt: Implications for crustal growth and recycling in the

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