Geochemical composition during experimental melting of basaltic flows from ODP Leg 152 and Leg 163 sites ...

• Main Authors: Thy, Peter, Lesher, Charles E, Mayfield, J D
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 1999
• Subjects: Ocean Drilling Program ODP; East Greenland; Greenland
• Online Access: https://dx.doi.org/10.1594/pangaea.804686; https://doi.pangaea.de/10.1594/PANGAEA.804686

A series of 1-atm. melting experiments on basaltic flows collected from Holes 918D and 989B in the oceanic succession of the East Greenland continental margin can be used to define possible phase equilibria and liquid lines of descent. A sample from Site 918 (Section 152-918D-108R-2) shows the melting order low-Ca pyroxene (1153ºC), augite (1182ºC), olivine (1192ºC), and plagioclase (1192ºC). A sample from Site 989 (Section 163-989B-10R-7) melts in the order of low-Ca pyroxene (1113ºC), augite (1167ºC), plagioclase (1177ºC), and olivine (1184ºC). In particular, the relatively early appearance of low-Ca pyroxene distinguishes the melting relations for the oceanic succession from those observed for the basaltic continental succession at Site 917. A basaltic andesite flow from the Middle Series at Site 917 (Section 152-917A-27R-4) shows the melting order of low-Ca pyroxene (1142ºC), plagioclase (1173ºC), and olivine (1173ºC). This melting order is difficult to reconcile with the observed large compositional ... : Supplement to: Thy, Peter; Lesher, Charles E; Mayfield, J D (1999): Low-pressure melting studies of basalt and basaltic andesite from the Southeast Greenland continental margin and the origin of dacites at Site 917. In: Larsen, HC; Duncan, RA; Allan, JF; Brooks, K (eds.) Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 163, 1-18 ...