• journal_title：Geology
• Contributor：Weidong Sun ; Richard J. Arculus ; Vickie C. Bennett ; Stephen M. Eggins ; Raymond A. Binns
• Publisher：Geological Society of America
• Date：2003-
• Format：text/html
• Language：en
• Identifier：10.1130/G19832.1
• journal_abbrev：Geology
• issn：0091-7613
• volume：31
• issue：10
• firstpage：845

The low Re abundance in arc-type volcanic rocks characterized by high ¹⁸⁷Os/¹⁸⁸Os ratios is an unsolved puzzle of the ¹⁸⁷Re-¹⁸⁷Os isotope system, leaving a significant gap in our understanding of the evolution of the upper mantle–continental crust system. Here we report new observations of high Re concentrations in fresh, submarine-erupted—i.e., relatively undegassed—island arc–like volcanic glasses dredged from the eastern Manus Basin, offshore Papua New Guinea. These observations, together with previously published reports of high Re concentrations in arc-type melt inclusions, indicate that undegassed arc-type volcanic rocks and the mantle wedge are enriched in Re. Consequently, the Re concentration in the continental crust is likely to be as high as ∼2 ppb, much higher than previously estimated. The low Re concentrations in subaerial arc-type volcanic rocks are probably due to Re loss during magma degassing.