Appendix B: U-Pb geochronology
Methods
   Zircon was separated using standard methods, including Wilfley shaking table, heavy liquids, and Franz magnetic separator and finally hand picking under the binocular microscope. Hand picked representative zircon grains from the 24 samples (40-70 grains for each sample) were  mounted in an epoxy puck along with the 1065 Ma Geostandard 91500 reference zircon (Wiedenbeck et al., 1995) and polished approximately half way through. Pre-analytical cathodoluminescence (CL) and secondary electron (SE) images were obtained using a Hitachi S4300 scanning electron microscope equipped with a Gathan mini-CL detector at Swedish Museum of Natural History (SMNH). Following CL and SE imaging samples were coated with ~30 nm of gold. Secondary ion mass spectrometer (SIMS) U-Th-Pb analyses were carried out using a large geometry CAMECA IMS 1270 instrument at the SMNH in three separate sessions. Instrumental set up broadly follows that of Whitehouse et al. (1999) and described in Lee and Whitehouse (2007). Pre-sputtering with a 25 μm raster for 120 seconds, centering of the secondary ion beam in the 4000 μm field aperture (FA), mass calibration, optimization and optimization of the secondary beam energy distribution were performed automatically for analyses in the latest two sessions. For two samples analyzed in t he first session, these operations were performed manually. In general we used 207 corrected (^238U/^206Pb) age [representing a projection from assumed Common Pb of 0.83 (Stacey and Kramers, 1975) through the analysis onto the Concordia as represented schematically by the regression lines in the Concordia plots,  in Fig. 6 (Ludwig, 2001)], as this is most appropriate for the age range seen for these rocks (generally 630-580 Ma), but in one case, (Iqna granite), ^207Pb/^206Pb ages are also presented and the reasoning is as discussed in the text. Age interpretations were performed using the routines of Isoplot/Ex (Ludwig, 2001). Decay constants follow the recommendations of Steiger and Jäger (1977). 
Zircon characteristics and ion probe U-Pb dating
Calc-alkaline (CA) suite
1 Elat-Shlomo (YE-11)
	Monzogranite:  Zircon CL images of this sample show dark, high-U (670 ppm on average, Table B1), fine to medium oscillatory zoned grains (Fig. 9-1a, 9-1b). Slight blurring of zoning is dominant in many grains mainly in the inner parts while some grains are characterized by a thin (~10 μm) darker rim that was not investigated in this work. The CL images and the U and Th concentrations show no simple distinction between xenocryst (see below) and newly formed zircon areas or grains (Fig. 7-1a, 7-1b).  
Of 15 analyses, 11 207 corrected ages yielded a weighted mean age of 636±7 Ma (MSWD: 1.7) which is interpreted as the crystallization of this pluton (Table 1, Fig. 6-1). Three other older ages yielded a weighted mean age of 800±18 Ma (MSWD 0.7) and these are interpreted to represent xenocrysts of that age (Table 1, Fig. 6-1). One younger age (Figure 6-1) is interpreted to show lead loss. We found no correlation between slightly blurred zoning and lead loss in the zircons of this sample.  
2. Elat-Rehavam (YE-34) 
	Monzogranite: Zircon CL images of this sample show bright low-U (178 ppm on average, Table B1) variably coarse to medium scaled oscillatory zoned cores rimmed by dark, high-U (1328 ppm on average, Table B1) rims (Fig. 9-2a, 9-2b). Sector zoning and extensive blurring of core areas is common, where as zoning is rarely detected in the dark rims.  As in the case of Elat-Shlomo granite no clear distinction exists between xenocrysts (see below) and newly formed zircon in either CL images or the U and Th concentrations. 
    Of 22 analyses, 6 207 corrected ages yielded a weighted mean age of 630±5 Ma (MSWD = 1.0) which is considered the most reliable estimate for the crystallization of this pluton (Table 1, Fig. 6-2). Two older ages yield a weighted mean of 904±16 Ma (MSWD: 1.4, 2σ-internal, 3a-core, 10a-core, Table B1) and represent xenocrysts of that age, while younger ages are interpreted to show lead loss. Alternatively, the oldest 13 (excluding the two xenocrysts), 207 corrected ages yields a weighted mean age of 624±5 Ma with an acceptable MSWD value of 1.8 which can be interpreted as the crystallization age of this rock while younger ages show lead loss. We prefer the former age interpretation because of its similarity with the age of the other pluton of Elat-granite (i.e., 1. Elat-Shlomo pluton) and the better MSWD value, but the latter interpretation cannot be ruled out. It may be of importance to note that the Th/U ratio of zircons from this pluton varies from 0.9 to less than 0.1 (Table B1). All zircons with very low Th/U ratios (<0.1), which are typical of metamorphic zircons (Hoskin and Schaltegger, 2003), yielded 207 corrected ages younger than ~615 Ma. This is in accordance with our interpretation that these grains have been affected by lead loss due to their high U content and consequent metamictization. As in the case of Elat-Shlomo pluton no correlation was found between blurred zoning in these grains and disturbance of the U-Th-Pb system. While some blurred zones show lead loss others show clearly the same 207 corrected age and Th/U ratios as non blurred zones. The same is true for the difference between bright low-U cores and dark high-U rims. While suspicious of metamictization due to their high-U content (up to 3400 ppm, Table B1), some of these dark rims appear to have experienced lead loss while others show the same 207 corrected age, and Th/U ratios as the low-U cores (Table B1).
 3. Timna Porphyrytic Granite (AG-69)
 	Monzogranite: CL images of zircons from this sample show homogenously spaced medium to bright (353 ppm U, Table B1) zoning. In most cases no clear distinction between core and rim areas is seen from these images, but in a few grains darker or brighter core area is seen (Fig. 9-3). 
    Of 11 analyses, the 6 older 207 corrected ages yielded a weighted mean age of 632±7 and an MSWD value of 1.8 (Table 1, Fig. 6-3). The younger 5 ages are interpreted as lead loss. 
4. Shahira layered intrusion (S-3807)
   Felsic layer (granodiorite): CL images of zircons from this sample show variably bright, low U (208 ppm on average, Table B1) widely spaced oscillatory zoned cores typical of zircons from mafic magmas (Corfu et al., 2003). Discordant rims are usually darker (in CL), higher in U, (up to 608 ppm, Table B1) but in some cases these are bright zones (Fig. 9-4). 
    Of 14 analyses, 13 207 corrected ages yielded a weighted mean age of 632 ±4 Ma with an MSWD of 1.1 (Table 1, Fig. 6-4) which is interpreted to represent the crystallization age of this rock. Another younger age is shows lead loss. Both cores and the discordant, dark or bright rims fall within this age spread and no distinction was found between the two groups of analyses.  
5. Zreir pluton (S-4557)
   Monzogranite: CL images of zircons from this sample show bright oscillatory to slightly darker low-U (402 ppm on average, Table B1) zoned cores rimmed in some cases by very thin (>5μm ) dark concordant rims not sampled in this work (Fig. 9-5a, 9-5b). Two exceptionally high-U rims (3500-8700 ppm) were also sampled.    
Of 14 analyses, 11 207 corrected ages yielded a weighted mean age of 629±6 Ma with an acceptable MSWD value of 1.8 (Table 1, Fig. 6-5) which is interpreted as the crystallization age of the pluton. The analysis 8b-rim with a high U and Th (8700 ppm U) plots slightly offset to the left from the other 11 grouped analyses and has a 207 corrected age of 657±7 Ma  (Table B1, Fig. 6-5). The core of the same grain plots within the group of the above-mentioned 11 analyses, implying that this point does not represent a xenocryst. The slight shift to the left from this group may be attributed to problems with the U-Pb calibration between standard and high U sample as a result from high accumulated radiation damage, as has been shown for reversely discordant high-U zircons elsewhere (McLaren et al., 1994). The common Pb corrected location on the Concordia is difficult to interpret due to the calibration affect and thus this point is disregarded from calculations of this age (Fig. 6-5). One younger age is interpreted to show lead loss (Fig. 6-5) while the analysis of 7a-rim (Table b1) yielded a 207 corrected age of 767 ±9 Ma (Table 1, Figure 6-5), and is interpreted as a xenocryst of this age.   
6. Hibran-Miar complex (S-2351)
	Monzodiorite: CL images of zircons from this sample, show widely spaced oscillatory zoned cores typical of zircons from mafic magmas (Corfu et al., 2003, Fig. 9-6). U content varies between 70-416 ppm with an average of 219 ppm (Table B1). Thin (<10 μm), concordant, bright rims envelope most grains but were not analyzed in this work. 
    All 15 207 corrected ages yield a weighted mean age of 619±4 Ma (MSWD: 0.5) which is interpreted to represent the crystallization age of this pluton (Table 1, Fig. 6-6).  
7. Ahdar pluton (S-2911)
	Granodiorite: CL images of zircons from this sample show bright, low U (207 ppm on average, Table B1) oscillatory zoned cores rimed by a concordant darker high-U [(962 ppm on average, Table B1) Fig. 9-7]. In a few cases dark high-U (~810 ppm, Table B1) cores exist.
    Of 9 analyses, 5 older 207 corrected ages yielded a weighted mean age of 610±5 Ma and an MSWD value of 0.5 (Table 1, Fig. 6-7) which is interpreted as the crystallization age of this rock. Four other younger ages are interpreted to show lead loss (Fig. 6-7). It is worth noting that the concordant rim analysis of grain 9a yielded a 207 corrected age older than its accompanying core analysis by ~20 Ma (Table B1). Pb loss along cracks may explain this feature although no clear signs of the latter were detected in CL images of this grain.   
8. Rahba pluton (S-2069)
 	Quartz-monzonite: CL images of zircons from this sample show bright (118 ppm on average, Table B1) complex oscillatory zoned cores and inner rims (Fig. 9-8). These in return, are usually rimmed by concordant, thin dark rims not sampled in this work. Within cores and inner rims, zoning is blurred to some extent in many grains and sector zoning is seen in some.
    All 8, 207 corrected analyses yielded a weighted mean age of 610±5 Ma with an MSWD of 1.2 (Table 1, Fig. 6-8), which is interpreted as the crystallization of this rock.           
9. Sama pluton (S-3704)
	Quartz-monzonite: CL images of zircons from this sample show variably dark, low U (135 ppm on average, Table B1) medium to coarse oscillatory zoned grains, with prominent sector zoning (Fig. 9-9). Bright, high U (400 ppm on average) blurred core or inner rim areas is also a common phenomenon, and in many cases this is accompanied by high Th (573 ppm on average, Table B1), and high Th/U ratio (1.4 on average, Table B1). The abundance of such high Th/U blurred zones in these zircons could imply that (metamorphic?) re-crystallization has affected these grains but the fact that the corresponding ages do not construct a different age group than the low Th/U grain area analyses precludes this interpretation. 
     Of 18 analyses, 13 207 corrected ages yielded a weighted mean age of 608±4 Ma with an MSWD value of 0.7 (Table 1, Fig. 6-9) which is interpreted as the crystallization age of this pluton. 5 younger ages are interpreted as showing lead loss.  
10. Lathi pluton (S-1610)
	Quartz-monzonite: CL images of zircons from this sample, show bright, low-U (143 ppm on average, Table B1), oscillatory zoned cores rimmed by concordant, darker high U (328 ppm on average, Table B1) oscillatory zoned rims (Fig. 9-10).
    Of 21 analyses, 19 207 corrected ages yielded a weighted mean age of 607±4 and an MSWD value of 1.5 interpreted to represent the crystallization age of this pluton (Table 1, Fig. 6-10). Two younger ages are interpreted to show lead loss.    
 11. Sulaf pluton (S-2199)
	Monzonite: CL images of zircons from this sample show variably bright low-U (241 ppm on average, Table B1) oscillatory to blurred zoned cores with prominent sector zoning , rimmed by concordant, dark, high U (510 ppm on average, Table B1) oscillatory zoned rims (Fig. 9-11).
    Of 14 analyses, 8 207 corrected ages yield a weighted mean age of 597±5 and an MSWD value of 1.0 (Table 1, Fig. 6-11), which is considered by us as the most reliable crystallization age for this pluton. Four younger ages are interpreted to show lead loss (Fig. 6-11), while two older ages are more difficult to interpret. 6d-rim is an analysis that yielded an older 207 corrected age than two core analyses of this grain (6d-core1, 6d-core2) by ~25 Ma (Table B1), thus not permitting to simply interpret this age as representing a xenocryst. We omitted this analysis from calculation, as it is set to the left (towards older ages) from the main group of analyses. Alternatively including this analysis in calculation, 8 207 corrected ages yield a weighted mean of 602±8 Ma (MSWD=1.7) which is insignificantly older than the age of ~597 Ma discussed above. The analysis of 1a-core  while having an U content of 345 ppm which is normal to this rock, has a significantly higher Th content and a high Th/U ratio (1.6, Table B1) than the rest of the zircon population in this rock and may represents a xenocryst of ~650 Ma. Thus, both older ages are disregarded in the age calculation of this pluton, but their interpretation is incomplete.  
. 12. Abu-K'sheib pluton (S-2695)
	Quartz-monzonite: CL images of zircons from this sample show bright, low-U (133  ppm on average, Table B1) oscillatory zoned cores with prominent blurring and sector zoning, rimmed by darker, high U (270 ppm on average, Table B1). In one case core oscillatory zoning is cut by newly formed rim zoning (Fig. 9-12 and see below).
    Of 9 analyses, 8 207 corrected ages yielded a weighted mean age of 592±7 Ma with an MSWD value of 1.3 (Table 1, Fig. 6-12), which is interpreted as the crystallization age of this pluton. One younger age apparently showing lead loss was omitted from this average. The CL image of grain 8a (Figure 9-12) may imply that an older core may exist within newly formed rim. The rim analysis (8a-rim) yielded a corrected 207 age of 588±6 Ma while the core analysis of this grain (8a-c) yielded a 207 corrected age of 607±7 Ma (Table B1), and thus 8a may represent a xenocryst. However, omitting this age from the weighted average (yielding: 589±5 and MSWD: 0.53) does not change the age of this rock significantly. 
Transitional plutons
13. Malaha pluton (S-4917)
	Monzonite: CL images of zircons from this sample show closely spaced bright oscillatory zoned grains (Fig. 9-13). In most cases darker high-U (530 ppm on average, Table B1) cores can be distinguished. These are rimmed by concordant, brighter low U (290 ppm on average, Table B1) rims. In a few cases bright sector zoning can be seen. 
    Of 18 analyses 15, 207 corrected ages yielded a weighted mean age of 605±4 Ma with an MSWD value of 1.0 (Table 1, Fig. 6-13), which is interpreted as the crystallization age of the rock. Three ages are excluded from this calculation: two younger ages are interpreted to show lead loss whereas one older age (of 3a-core) may represent a xenocryst of ~640 Ma (Tables 1, 3 Figure 6-13). While the CL image of grain 3a does not show a clear discordant core-rim relationship, the U content of the core (3a-core: ~1700 ppm, Table B1) is 3-5 times higher than other grains and 5 times higher than its rim, thus supporting the interpretation that this is a xenocryst.      
14. Girgar pluton (S-1561)
 	Monzogranite: CL images of zircons from this sample show variably bright, low-U (185 ppm on average, Table B1) oscillatory zoned grains. Dark, high-U (up to ~600 ppm, Table B1) areas occur both, in cores or as thin, concordant rims. Sector zoning and blurring of bright core or inner rim areas is common (Fig. 9-14). 
    Of 18 analyses, 12 207 corrected ages yielded a weighted mean age of 604±4 Ma with an MSWD value of 1.1 (Table 1, Fig. 6-14). Younger ages are interpreted to show lead loss (Fig. 6-14). Analysis of 3a-rim yielded a 207 corrected age of ~630 Ma which is older than the corresponding core analysis of 3a-core of ~596 Ma (Table 1, Fig. 6-14). The former analysis was omitted from the age calculation.
Alkaline (AL) suite
15. Sahara pluton (S-1542)
	Alkali-feldspar granite: CL images of zircons from this sample show very fine-scale oscillatory, bright, low-U (281 ppm on average, Table B1) cores with prominent sector zoning (Fig. 9-15), in some cases rimmed by concordant, dark high-U rims (871 ppm on average, Table B1). Some grains show oscillatory bright and dark areas, where dark rims may be rimmed by secondary, concordant, thin rims (~10 μm), not sampled in this work, or may contain dark high-U (801 ppm on average, Table B1) core areas.
   Of 13, 207 corrected ages 11 yielded a weighted mean age of 608±5 Ma (MSWD: 1.2) (Table 1, Fig. 6-15), which is interpreted as the crystallization age of this pluton. Two other ages show apparent lead loss (Fig. 6-15).
16. Yehoshafat pluton (AG-81)
	Alkali feldspar granite: CL images of zircons from this sample show generally fine-scale, bright, low-U (204 ppm on average, Table B1) oscillatory zoned grains. In some cases bright or dark blurring of inner grain areas occur (Fig. 9-16).
    The 207 corrected ages of all 12 analyses yielded a weighted mean age of 605±4 and an MSWD value of 1.4 which is interpreted as the crystallization age of this pluton (Table 1, Fig. 6-16).
17. Timna Alkali Granite (AG-68)  
	Alkali feldspar granite: CL images of zircons from this sample show generally bright, low U (228 ppm on average, Table B1) oscillatory zoned grains. In some cases sector zoning or thin (<10 μm) may be detected in some grains (Fig. 9-17). 
    Of 13 analyses 10, 207 corrected ages yielded a weighted mean age of 606±3 Ma with an MSWD value of 0.8 (Table 1, Fig. 6-17) which is interpreted to represent the crystallization age of this pluton. Another three younger ages are interpreted to show lead loss.
18. Timna Monzodiorite (AG-77)
	Monzodiorite: CL images of zircons from this sample show variably bright, low U (168 ppm on average, Table B1) widely spaced oscillatory zoned grains typical of zircons from mafic magmas (Corfu et al., 2003), or more fine-scale oscillatory zoning (Fig. 9-18). Sector zoning is a wide phenomenon. 
    Of 10 analyses, 9 207 corrected ages yielded a weighted mean age of 602.0±5.2 Ma with an MSWD value of 1.8. Another younger age is interpreted to show lead loss (Table 1, Fig. 6-18).
19. Umm-Shomer pluton (S-1886)
 	Syenogranite: CL images of zircons from this sample show variably dark to bright, low-U (166 ppm on average, Table B1), oscillatory zoned cores and inner rims with prominent bright blurring of different zones. In several grains these are rimmed by dark high U (272 on average, Table B1) rims (Fig. 9-19). 
   Of 15 analyses, 7 207 corrected ages yielded a weighted mean age of 596±5 with an MSWD value of 1.4 (Table 1, Fig. 6-19). Another 8 younger ages are interpreted to show lead loss. 
20. Sharm pluton (S-1518) 
	Alkali feldspar granite: CL images of zircons from this sample show very fine-scale, bright, low U (119 ppm on average, Table B1), oscillatory zoned grains with prominent sector zoning (Fig. 9-20).
    All 15 207 corrected ages yielded a weighted mean age of 594±4 Ma with an MSWD value of 0.7 (Table1, Fig. 6-20), which is interpreted as the crystallization age of this pluton.   
21. Dahab pluton (S-3896)
	Syenogranite: CL images of zircons from this sample show variably bright, generally low U (143 ppm on average, Table B1), very fine-scale oscillatory zoned grains. Blurred areas and sector zoning are common within cores and concordant, thin (~5-10 μm), dark rims are developed in some grains (Fig. 9-21).
    Of 10 analyses, 8 207 corrected ages yielded a weighted mean age of 591±6 with an MSWD value of: 1.4 (Table 1, Fig. 6-21) which is interpreted as the crystallization age for this pluton. Two younger ages are interpreted to show lead loss. 
22. Umm-I-Fai (S-4403)
	Alkali feldspar granite: CL images of zircons from this sample show bright, high U (947 ppm on average, Table B1) very fine-scale oscillatory zoned cores, rimmed by concordant, dark, higher-U (1579 ppm on average, Table B1) oscillatory zoned rims. Blurring of both core and rim areas characterizes almost all grains and obscures the fine-scaled oscillatory zoning, while sector zoning is almost absent (Fig. 9-22).  
    Of 9 analyses, the 8 older, 207 corrected ages yielded a weighted mean age of 586±4 (MSWD: 1.7) (Table 1, Figure 6-22), interpreted to represent the crystallization age of this pluton, while, one younger age shows lead loss.
23. Katharina pluton (DV 82-87) 
	Syenogranite: CL images of zircons from this sample show variably, bright to dark (330 ppm U on average, Table B1), oscillatory zoned grains. Bright, blurred core areas are common whereas, in some cases, dark rims (not sampled in this work) envelope brighter cores (Fig. 9-23). 
    Of 11 analyses, 9 207 corrected ages yielded a weighted mean age of 583±6 Ma with an MSWD value of 1.8 (Table 1, Fig. 6-23), interpreted as the crystallization of this pluton where as the 2 younger ages show lead loss (Fig. 6-23). 
24. Iqna pluton (YS-503)
	Syenogranite: CL images of zircons from this sample show a bimodal zircon population. A minority of bright, low-U (363 ppm on average, Table B1), oscillatory zoned grains are found, along with a majority of dark, high U (4835 ppm on average and up to ~7000 ppm, Table B1) grains with no visible oscillatory zoning (Fig. 9-24a, 9-24b). Of 13 analyses 7 are low-U and 6 are high-U (363 and 4835 ppm respectively, Table B1). 
   Analyses corresponding to the two zircon populations, (i.e., low and high-U) show different trends in their scatter on the concordia diagram. While most low-U analyses are grouped at ~580 Ma, high-U analyses plot as variably concordant, discordant and reversely discordant. Of the 13 analyses 6, 207 corrected ages (5 low-U, and 1 high-U analyses) yielded a weighted mean age of 578±8 Ma and MSWD value of 1.7 (Table 1, Fig. 6-24). Two older ages (3d-core: 615 Ma; 3-c-core: 630 Ma, Table B1) of reversely discordant (high-U) analyses and another 5 younger ages were omitted from calculation of this age.  It may be of importance to note that the 6 high-U analyses yielded a ^207Pb/^206Pb weighted mean age of 594±6 Ma with an MSWD value of  0.3  (Table 1, Fig. 6-24 inset), slightly (but significantly when errors are considered) older than the age of 6 grouped analyses (5 low-U, and 1 high-U analyses). ^207Pb/^206Pb ages as young as ~700 Ma are generally considered unreliable due to low count rates of radiogenic Pb (especially ^207Pb) which makes them more susceptible to uncertainty in measurement of common Pb based on ^204Pb counts that may be indistinguishable from detector background noise. However, high-U (and consequently high radiogenic Pb) analyses are much less susceptible to these problems and are thus considered reliable.  The reversely discordant analyses may be attributed to problems with the U-Pb calibration that result from high levels of accumulated damage (McLaren et al., 1994). It is, however, important to mention that the effect of high-U concentration on the U-Pb calibration should not affect the ^207Pb/^206Pb ages. The occurrence of high and low-U within the same rock sample is an unexplained feature but variance of this magnitude of U content has been reported for in other studies (Hoskin and Schaltegger, 2003). Importantly, the Th/U ratio of low and high-U are approximately the same varying between 0.3 and 0.7 (Table B1), which indicates that these may be original magmatic variations of U and accompanying Th contents in the zircon population. Inheritance of either of the zircon populations seems unreasonable. High-U zircons comprise the majority of the zircon population and thus are not xenocrysts, and low-U grains yield younger ages and thus, are too, not probable xenocrysts.
   We suggest that the 578±8 Ma is the most reliable crystallization age of this pluton and that 5 younger ages represent lead loss, while reversely discordant analyses are explained by the problematic U-Pb calibration during measurement as explained above. However, the 594±6 Ma ^207Pb/^206Pb age, calculated by using only high-U zircons can not be ruled out.  
Figure captions:
Figure 9: Representative Cathodoluminescence (CL) images of dated rocks. Analyzed spots and corresponding 207-corrected ages in Ma (± 1σ) are shown. White bar corresponds to 100μm. Numbering 1-24 corresponds to Fig. 1 and Table 1. Exceptions are: 1: Elat Shlomo-magmatic zircon, 1.Xen: Elat Shlomo-xenocryst, 2: Elat Rehavam-magmatic zircon, 2.Xen: Elat Rehavam-xenocryst, 5: Zreir-magmatic zircon, 5.Xen: Zreir-xenocryst, 24: Iqna low-U and high-U zircons, 24 respectively.