DATA REPOSITORY. The Ellsworth Terrane, Coastal Maine: Geochronology, Geochemistry, and Nd-Pb Isotopic Composition Implications for the Rifting of

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1 DATA REPOSITORY The Ellsworth Terrane, Coastal Maine: Geochronology, Geochemistry, and Nd-Pb Isotopic Composition Implications for the Rifting of Ganderia Klaus J. Schulz 1*, David B. Stewart 2, Robert D. Tucker 2,3, Jeffrey C. Pollock 4 and Robert A. Ayuso National Center, U.S. Geological Survey, Reston, VA A National Center, U.S. Geological Survey, Reston, VA Department of Earth and Planetary Sciences, Washington University of St. Louis, Saint Louis, MO Department of Marine, Earth and Atmosphere Sciences, Campus Box 8298, North Carolina State University, Raleigh, NC ; present address: School of GeoSciences, The University of Edinburgh, Edinburgh, UK EH9 3JW SAMPLE COLLECTION AND ANALYTICAL METHODS TABLES DR-1-4: CHEMICAL ANALYSES OF BASALTS AND RHYOLITES FROM THE ELLSWORTH TERRANE

2 SAMPLE COLLECTION AND ANALYTICAL METHODS Most of the analyzed samples were collected during regional geologic mapping of the Blue Hill, Castine, and part of the Rockland and Deer Isle 15 quadrangles, northern Penobscot Bay (Stewart, 1998). In addition, data for six samples (E-623, B1, B2, B3, G- 2, GS-2) from the northern part of the Vinalhaven 15 quadrangle (Pinette and Osberg, 1989) are included here along with five samples of the North Haven Greenstone previously reported by Gates (2001). Samples from the Ellsworth Schist and Castine Volcanics were analyzed for major and trace elements in the analytical laboratories of the U. S. Geological Survey using the following techniques: major elements by wavelength dispersive x-ray fluorescences spectrometry (WDXRF) using glass discs (Taggart et al., 1987); the trace elements Ba, Rb, Sr, Zr and Y by energy dispersive x-ray fluorescence spectrometry (EDXRF) using glass disks (Johnson and King, 1987); and all other trace elements by instrumental neutron activation (Baedecker and McKown, 1987). Water, CO 2, and iron as FeO were determined by standard chemical methods (Jackson et al., 1987) for most samples; for a few samples only loss on ignition was determined. U-Pb isotopic analysis of zircon Ten- to twenty-kilogram samples for isotopic dating were collected from natural exposures. Following pulverization in a jaw-crusher and rotary disc-mill, zircon was extracted using Wilfley table concentration, and separation by heavy liquid and magnetic susceptibility methods. Individual grains of zircon were selected by hand picking, and were abraded and cleaned as is standard treatment for isotopic dilution methods. All zircons were analyzed at Washington University, Saint Louis using the procedures outlined by Krogh (1973, 1982), using mass spectrometry methods described by Tucker et al. (2001). Total procedure blanks were 3-1 pg for Pb and less than one pg for U. Total common-pb contents for the analyses reported (Table 1) range between 3 and 1 pg. Initial-Pb compositions were calculated from the Pb-evolution model of Stacey and Kramers (1975) at the estimated age of the rock, and the error of the initial-pb composition was assumed to be 4 % (2σ). In all cases reported here, even large variation in initial-pb compositions result in insignificant changes to the calculated ages. Error propagation is similar to that described by Ludwig (1980), and the analytical reproducibility of the mineral fractions confirms that the parameters used in the data reduction and their errors have been evaluated correctly. Because most of the zircon analyses cluster within the analytical error of concordia, the cited age is the average of the 207 Pb/ 206 Pb ages, weighted according to the inverse variance of the individual ages (Ludwig, 1992); the age error is simply the standard error of the average value calculated using the assigned error for each analysis. The reproducibility of the isotopic ages can be evaluated by the mean square of the weighted deviates (MSWD) which is the measure of the observed scatter to that predicted by the assigned errors of each data point. In most cases the MSWD is much less than one indicating that the errors assigned are overestimated. All uncertainties are quoted, and shown in the concordia figures, at the 95% confidence limit.

3 Sm-Nd isotope analysis Selected samples were analyzed for Sm-Nd isotopes in the Radiogenic Isotope Laboratory at Memorial University of Newfoundland. Approximately 0.1 g of rock powder was dissolved in Savilex Teflon beakers using a mixture of concentrate HF HNO3 acids. A mixed 150 Nd/ 149 Sm spike was added to each sample prior to acid digestion. Both sample and spike were weighed on a high-precision balance. After five days of digestion, the solution was evaporated to dryness and then taken up in 6 N HCl acid for two days. The solution was then dried and taken up in 2.5N HCl and loaded on cationic exchange chromatography using AG50W X8 resin to collect the REE fractions. The REE fractions were then purified and Sm and Nd were isolated using a secondary column loaded with Eichrom Ln resin. All reagents were purified in order to insure a low contamination level. The measured total chemical blanks ranged between 40 and 90 pg and are considered negligible. Sm and Nd concentrations and Nd isotopic compositions were analyzed using a multicollector VG 54 mass spectrometer in dynamic mode. Nd isotopic ratios were normalized to 146 Nd/ 144 Nd = The reported values were not adjusted to an external standard, as the Jndi-1 isotopic standard was used for the first time during the course of the present study. Two runs of this standard yielded a mean value of ± (% Std Err) in agreement with the database on the same material. The certified value of this standard is ± 7. The in-run precisions on Nd isotopic ratio are given at 95% confidence level. Errors on Nd isotopic compositions are <0.002% and errors on the 147 Sm/ 144 Nd ratio are estimated to be lower than 0.1%. The ε Nd values were calculated using 147 Sm/ 144 Nd = and 143 Nd/ 144 Nd = values for the present day chondrite uniform reservoir (CHUR). 147 Sm decay constant is 6.54 x /yr (Steiger and Jäger, 1977). T DM was calculated with respect to the depleted mantle model of De Paolo (1981). Pb isotope analysis Sample powders were washed and rinsed in ultrapure water and then leached in 3N HCl. After leaching the samples were dissolved in a mixture of HF and HNO 3, and the Pb separated by anion exchange using HBr-HNO 3 mixtures as eluent as done previously (Ayuso et al., 2004). About 150 ng of Pb was loaded with silica gel and H 3 PO 4 on single rhenium filaments and analyzed using a multicollector, automated Finningan MAT-262 mass spectrometer at the U.S. Geological Survey, Reston, VA. Samples and standards were analyzed under identical running conditions (static mode). Runs were carefully monitored during analysis (e.g., stable run temperatures at 1350 ± 25º) to minimize the effects of mass fractionation. Pb isotope ratios were measured to a precision of at least ~0.1% at 2σ and corrected for mass fractionation by comparison with ratios measured on NBS SRM 981 (n = 18). Isotopic data during the course of this study show a variation in 207 Pb/ 204 Pb of ~0.43%, 206 Pb/ 204 Pb of ~0.33%, and 208 Pb/ 204 Pb of ~0.52%. A total Pb blank of less than 50 pg was obtained so that the measured Pb isotope compositions did not need further corrections. U, Pb, and Th concentrations typically show 2σ analytical uncertainties better than ±3%. 207 Pb/ 206 Pb ages were calculated (Ludwig, 1992) according to the crustal Pb evolution model (Stacey and Kramers, 1975).

4 REFERENCES Ayuso, R.A., Kelley, K.D., Leach, D.L., Young, L.E., Slack, J.F., Wandless, G. Lyon, A.M., and Dillingham, J.L., 2004, Origin of the Red Dog Zn-Pb-Ag deposits, Brooks Range, Alaska: Evidence from regional Pb and Sr isotope sources: Economic Geology, v. 99, p Baedecker, P.A., and McKown, S.T., 1987, Instrumental neutron activation analysis of geochemical samples, in Beadecker, P.A., ed., Methods in Geochemical Analysis: U.S. Geological Survey, Bulletin 1770, Chapter H, p. H1-H14. DePaolo, D.J., 1981, Neodymium isotopes in the Colorado Front Range and crust-mantle evolution in the Proterozoic: Nature (London), v. 291, p Gates, Olcott, 2001, Bedrock geology of North Haven and Vinalhaven Islands. Open- File No , p. 1-28, Maine Geological Survey, Department of Conservation, Augusta, Maine. Jackson, L.L., Brown, F.W., and Neil, S.T., 1987, Major and minor elements requiring individual determination, classical whole rock analysis, and rapid rock analysis, in Beadecker, P.A., ed., Methods in Geochemical Analysis: U.S. Geological Survey, Bulletin 1770, Chapter G, p. G1-G23. Jaffey, A.H., Flynn, K.F., Glendenin, L.E., Bently, W.C., and Essling, A.M., 1971, Precision measurement of the half-lives and specific activities of U235 and U 238: Physical Review C 4, p Johnson, R.G., and King, B.,-S., L., 1987, Energy-dispersive X-ray fluorescence spectrometry, in Beadecker, P.A., ed., Methods in Geochemical Analysis: U.S. Geological Survey, Bulletin 1770, Chapter F, p. F1-F5. Krogh, T.E., 1973, A low contamination method for hydrothermal decomposition of zircon and extraction of U and Pb for isotopic age determination: Geochimica et Cosmochimica Acta, v. 37, p Krogh, T.E., 1982, Improved accuracy of U-Pb zircon ages by the creation of more concordant systems using an air-abrasion technique: Geochimica et Cosmochimica Acta, v. 46, p Ludwig, K.R., 1980, Calculations of uncertainties of U-Pb isotope data: Earth and Planetary Science Letters, v. 46, p Ludwig, K.R., 1992, ISOPLOT: A plotting and regression program for radiogenicisotope data, version 2.57: U.S. Geological Survey Open File Report , 49 pp. Pinette, S.R., and Osberg, P.H., 1989, Geological aspects of volcanic rocks on islands in East Penobscot Bay, Maine, in Tucker, R.D., and Marvinney, R.G., eds, Studies in Maine Geology, v. 3, p Stacey, J.S. and Kramers, J.D., 1975, Approximation of terrestrial lead isotope evolution by a two-stage model: Earth and Planetary Science Letters, v. 26, p Stewart, D.B., 1998, Geology of Northern Penobscot Bay, Maine: U.S. Geological Survey Miscellaneous Investigations Series, Map I-2551, 2 sheets, scale 1:62,5000. Steiger, J.S., and Jäger, E., 1977, Subcommision on Geochronology: Convention of the use of decay constants in geo- and cosmochronology: Earth and Planetary Science Letters, v. 36, p

5 Taggart, J.E. Jr., Lindsay, J.R., Scott, B.A., Vivit, D.V., Bartel, A.J., and Stewart, K.C., 1987, Analysis of geologic materials by wavelength-dispersive X-ray fluorescence spectrometry, in Beadecker, P.A., ed., Methods in Geochemical Analysis: U.S. Geological Survey, Bulletin 1770, Chapter E, p. E1-E19. Tucker, R.D., Osberg, P.H., and Berry, H.N., IV, 2001, The Geology of a Part of Acadia and the Nature of the Acadian Orogeny Across Central and Eastern Maine: American Journal of Science, v. 301, p

6 Table DR-1. Chemical analyses of Tb-1 tholeiitic basalts Ells Ells Ells Ells Ells Ells Ells Ells Ells Ells NH NH Cast Cast Cast Cast Cast Cast Cast Cast Cast Sample S67-18 S67-58 S67-85 S67-107A S S S S S S54-74M S E623 S67-54 S67-70 S67-73 S S S68-124c S S68-203C S SiO 2 (wt.%) Al 2 O Fe 2 O FeO MgO CaO Na 2 O K 2 O TiO P 2 O MnO H 2 O+/LOI H 2 O CO Total Anhydrous SiO 2 (wt.%) Al 2 O FeOt MgO CaO Na 2 O K 2 O TiO P 2 O MnO Total Rb (ppm) < Sr Cs < < < < Ba Co Cr <10 Sb < <0.7 <0.7 <0.8 <0.6 Y Zr Hf Ta 0.34 < < < Th 0.4 <0.5 < < < < <0.6 < U 0.2 <0.4 < <0.5 < <0.4 <1.0 < < <0.5 <0.4 < < Zn < Sc La Ce Nd Sm Eu Gd Tb Ho Tm Yb Lu Ells = Ellsworth Schist; NH = North Haven Greenstone; Cast = Castine Volcanics

7 Table DR-2 Chemical analyses of Tb-2 tholeiitic basalts Cast Cast Cast Cast Cast Cast Cast Cast Cast Cast Cast Sample S S S S S S70-41 B-1 B-2 B-3 G-2 GS-2 SiO 2 (wt.%) Al 2 O Fe 2 O FeO MgO CaO Na 2 O K 2 O TiO P 2 O MnO H 2 O+/LOI H 2 O CO Total Anhydrous SiO 2 (wt.%) Al 2 O FeOt MgO CaO Na 2 O K 2 O TiO P 2 O MnO Total Rb (ppm) <5 5 5 <5 5 Sr Cs < < <0.4 Ba Co Cr Sb < < < Y Zr Hf Ta Th < U < <0.5 <0.4 < <0.5 Zn Sc La Ce Nd Sm Eu Gd Tb Ho Tm Yb Lu Ells = Ellsworth Schist; Cast = Castine Volcanics

8 Table DR-3. Chemical analyses of R-1 felsic volcanic rocks Altered samples Ells Ells Ells Ells Ells Ells Ells Ells Ells Cast Cast Cast Cast Ells Cast Cast Cast Sample S67-17 S67-19 S67-62 S67-99 S S70-31 ME-179 ME-183 ME-186 S S69-51 S70-45 S S S S S SiO 2 (wt.%) Al 2 O Fe 2 O FeO MgO CaO Na 2 O K 2 O TiO P 2 O MnO H 2 O+/LOI H 2 O CO Total Anhydrous SiO 2 (wt.%) Al 2 O FeOt MgO CaO Na 2 O K 2 O TiO P 2 O MnO Total Rb (ppm) <5 40 <5 <5 Sr Cs Ba Co Cr Sb < Y Zr Hf Ta Th U < Zn < Sc La Ce Nd Sm Eu Gd Tb Ho Tm Yb Lu Ells = Ellsworth Schist; Cast = Castine Volcanics

9 Table DR-4. Chemical analyses of R-2 felsic volcanic rocks Altered samples Ells Ells Cast Cast Cast Cast Cast Cast Cast Cast Cast Cast Cast Cast Cast Cast Cast Cast Cast Sample S67-32 ME-185 S67-23 S67-93 S S S S S S S69-28 S70-19 S70-36 S70-42 S70-50 S S S S SiO 2 (wt.%) Al 2 O Fe 2 O FeO MgO CaO Na 2 O K2O TiO P 2 O MnO H 2 O+/LOI H 2 O CO Total Anhydrous SiO 2 (wt.%) Al 2 O FeOt MgO CaO Na 2 O K 2 O TiO P 2 O MnO Total Rb (ppm) Sr Cs < Ba Co Cr < <3.0 < < < < <5.0 < <5.0 Sb < Y Zr Hf Ta Th U < Zn Sc La Ce Nd Sm Eu Gd Tb Ho Tm Yb Lu Ells = Ellsworth Schist; Cast = Castine Volcanics