| Chemical Composition: | Orthopyroxene megacryst #1 (core Fs17.7Wo3.3; mantle Fs23.4-31.1Wo3.4-3.8; rim Fs37.6-42.5Wo2.9-3.3; FeO/MnO = 21-26, Cr2O3 = 0.3-0.5 wt.%; N = 6), orthopyroxene megacryst #2 (core Fs14.4±0.0Wo2.2-2.3; mantle Fs19.2-28.7Wo2.0-2.1; rim Fs33.1-36.8Wo2.8-3.5; FeO/MnO = 17-26; Cr2O3 = 0.3-1.0 wt.%; N = 7), orthopyroxene megacryst #3 (core Fs22.8Wo1.2; mantle Fs30.8Wo2.2; rim Fs43.5Wo2.5; FeO/MnO = 16-23; Cr2O3 = 0.2-0.4 wt.%; N = 3), pigeonite megacryst (core Fs21.3Wo7.0; mantle Fs23.4Wo11.8; rim Fs40.7Wo5.0; FeO/MnO = 17-20; Cr2O3 = 0.3-0.8 wt.%; N = 3), augite megacryst (core Fs14.7-19.4Wo38.5-30.2; rim Fs24.7Wo38.1; FeO/MnO = 15-18; Cr2O3 = 1.1 wt.%; N = 4), groundmass exsolved pigeonite (low-Ca pyroxene host Fs42.3-52.2Wo2.9-4.6, FeO/MnO = 21-23, N = 6; augite exsolution lamellae Fs18.1-25.9Wo40.8-38.1, FeO/MnO = 18-22, N = 5), groundmass plagioclase (oligoclase cores and intergrown with pyroxene megacrysts Ab68.8-79.0An26.7-17.9Or4.4-2.6, N = 6; albitic rims on laths Ab84.4-86.7An11.4-7.1Or4.2-7.0, N = 5), K-feldspar exsolution blade in albite (Or84.1Ab11.3An4.6), Fe metal (Ni = 0.13-0.18 wt.%, N = 2). Oxygen isotopes (K. Ziegler, UNM): analyses of acid-washed subsamples of groundmass and an orthopyroxene megacryst by laser fluorination gave, respectively: groundmass δ17O 1.548, 1.788, 1.831, 1.773; δ18O 3.201, 3.657, 3.728, 3.593; Δ17O -0.142, -0.143, -0.137, -0.123 (linearized, all per mil, TFL slope = 0.528); megacryst δ17O 1.780, 1.639, 1.682; δ18O 3.594, 3.329, 3.379; Δ17O -0.117, -0.119, -0.103 (linearized, all per mil, TFL slope = 0.528). Magnetic susceptibility log χ (× 10-9 m3/kg) = 3.06. |
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