Late Proterozoic transpression on the Nabitah fault system-implications for the assembly of the Arabian Shield

J. E. Quick

doi:10.1016/0301-9268(91)90008-x

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Late Proterozoic transpression on the Nabitah fault system-implications for the assembly of the Arabian Shield

J. E. Quick

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Abstract

The longest proposed suture zone in Saudi Arabia, the Nabitah suture, can be traced as a string of ophiolite complexes for 1200 km along the north-south axis of the Arabian Shield. Results of a field study in the north-central shield between 23° and 26°N indicate that the Nabitah suture is indeed a major crustal discontinuity across which hundreds of kilometers of displacement may have occurred on north-south trending, subvertical faults of the Nabitah fault system. Although not a unique solution, many structures within and near these faults can be reconciled with transpression, i.e., convergent strike-slip, and syntectonic emplacement of calc-alkaline plutonic rocks. Transcurrent motion on the Nabitah fault system appears to have began prior to 710 Ma, was active circa 680 Ma, and terminated prior to significant left-lateral, strike slip on the Najd fault system, which began sometime after 650 Ma. Northwest-directed subduction in the eastern shield could have produced the observed association of calc-alkaline magmatism and left-lateral transpressive strike slip, and is consistent with interpretation of the Abt schist and sedimentary rocks of the Murdama group as relics of the associated accretionary wedge and fore-arc basin.

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Precambrian Research Article

Source-reported bounding extent: 17.232039827369746° to 29.844806244493924° latitude; 34.53381976317553° to 44.4727706393204° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

J. E. Quick. 1991. Late Proterozoic transpression on the Nabitah fault system-implications for the assembly of the Arabian Shield. https://doi.org/10.1016/0301-9268(91)90008-x

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