170: Xenolith mineralogy and texture

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171: Primary (P) and secondary (S) magmas from volcanic arcs and melts * Note - (1) Basalt, Adagdak Volcano, Aleutians, selvage of wehrlite xenolith ADAG81-DR (also contains 0.21 MnO). (2) OK4, Okmok Volcano, Aleutians, (Byers 1961, primary magma of Kay et al. 1982, Conrad and Kay 1984). (3) ID16, Okmok volcano, Aleutians, one primary magma of Nye and Reid (1986). (4) High-Al basalt, experimentally derived by crystal fractionation from olivine tholeiite at 0.8 Gpa (8kbars) by Gust and Perfit (1987). (5) High-Al basalt at equilibrium with mantle lherzolite at 1.7 Gpa (17kbars), 1325oC, Tatsumi et al. (1983). (6) Basalt equilibrated with spinel lherzolite at 1.0 Gpa (10kbars), 1290oC, Fujii and Scarfe (1985). (7) High-Al basalt, Atka, Aleutians, proposed as primary magma derived from melting of ecolgite, Marsh (1982). The Adagdak ultramafic xenoliths cannot be derived from this magma and it is considered a derivative magma in this paper. *

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172: Representative olivine compositions in Adagdak xenoliths * Note - All mineral analyses were done using a JEOL-733 electron microprobe with Tracor-Northern automation at Cornell University. Analytical procedures are as in Conrad and Kay (1984). MnO error is ±0.03. Ordering of xenoliths is determined by their modal percent olivine. *

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173: Representative clinopyroxene compositions in Adagdak xenoliths

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174: Representative amphibole compositions

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175: Representative spine compositions in Adagdak xenoliths

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176: Plagioclase compositions xenolith ADG-1

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177: Trace element content of Adak xenoliths and host lavas * Source: - Analyses by INAA (Cornell University) except Rb, Sr, and Nd by isotope dilution (Cal Tech). Analytical techniques as in Kay et al. (1983). Counting times for ultramafic xenoliths up to 16hrs. Fe (as FeO) is 10.82% in BHVO; 11.09% in SAR11. SAR11 is Aleutian basalt from Westdahl volcano and a Cornell standard (Ta concentration reflects contamination from WC grinding container). Values for USS standard BHVO are concentrations used at Cornell. *

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702: Primary (P) and secondary (S) magmas from volcanic arcs and melts

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