Ophiolite metamorphic soles preserve important records of ophiolite emplacement, but there have been few detailed investigations into their non‐mafic portions. We present new thermobarometric and petrochronologic data from a metasediment and mafic restite in the upper Wadi Tayin sole exposure in the Samail (Oman‐UAE) Ophiolite. Thermodynamic modeling suggests metasedimentary garnet nucleation at ~4 kb, ~550°C and final growth at 7.5 ± 1.2 kbar, 665 ± 32°C, occurring by 93.0 ± 0.5 Ma (Lu‐Hf isochron). Zircon U‐Pb dates of 106.9 ± 2.3 (detrital) and 98.7 ± 1.7 to 94.1 ± 1.6 Ma (metamorphic) bracket the initiation of metamorphism, and monazite U‐Pb dates from ~97–89 Ma suggest a lengthy period of growth or recrystallization. A mafic titanite U‐Pb age of 92.2 ± 1.8 Ma records the earliest possible juxtaposition of high‐ and lower‐grade sole rocks. These and other data suggest that (i) the Wadi Tayin sole preserves an inverted metamorphic, metasomatic, and age gradient,(ii) metasediment metamorphism occurred during, or soon after, crystallization of the overlying ophiolite (≤96.5 Ma); and (iii) sole metasediments define a thermal gradient continuous with hotter, higher‐
High‐precision dating of the metamorphic sole of ophiolites can provide insight into the tectonic evolution of ophiolites and subduction zone processes. To understand subduction initiation beneath a young, well‐preserved and well‐characterized ophiolite, we performed coupled zircon laser‐ablation inductively coupled mass spectrometry trace element analyses and high‐precision isotope dilution‐thermal ionization mass spectrometry U–Pb dating on 25 samples from the metamorphic sole of the Samail ophiolite (Oman‐United Arab Emirates). Zircon grains from amphibolite‐ to granulite‐facies (0.8–1.3 GPa, ~700–900°C), garnet‐ and clinopyroxene‐bearing amphibolite samples (
- Award ID(s):
- 2120931
- NSF-PAR ID:
- 10411440
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Metamorphic Geology
- Volume:
- 41
- Issue:
- 6
- ISSN:
- 0263-4929
- Page Range / eLocation ID:
- p. 817-847
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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