Geodynamic significance of Neoarchean metasedimentary belts in the Superior Province: Detrital zircon U-Pb LA-ICP-MS geochronology of the Opinaca and La Grande subprovinces

•Opinaca subprovince of the Superior has high proportion of Neoarchean detrital zircon.•La Grande transitional and successor basin detrital zircon ages are similar to Opinaca.•Deposition in both subprovinces occurred over a period ca. 2715–2695 Ma.•Provenance of both regions is interpreted to be La Grande and Minto rocks.•Regional geology and detrital age distributions suggest an extensional setting. Metasedimentary subprovinces within the Superior Province and many Archean cratons worldwide occur as prominent belts separating volcano-plutonic subprovinces. The stages of their development mark major, distinct geodynamic events. Deposition ubiquitously follows a restricted period of voluminous, regional, felsic pluton emplacement. Their geodynamic setting of deposition is not well understood, and despite similar sedimentological, structural and post-deposition metamorphic characteristics, metasedimentary subprovinces have been variously interpreted as developing in accretionary prism, syn-orogenic, and back-arc basin settings. We present the first synthesis of detrital zircon U-Pb LA-ICP-MS geochronology from paragneiss and migmatite of the Opinaca and La Grande subprovinces. This study constrains detrital zircon age populations of the sedimentary protoliths, assesses their provenance, and evaluates the geodynamic setting of deposition. Including detrital geochronology compiled from regional literature, nine paragneiss samples from the Laguiche Complex (Opinaca) and eleven from the Rivière Salomon, Thor, Keyano, Magin, Marbot, Low and Ekomiak formations (La Grande) provide dominant modal age peaks similar to regional Neoarchean felsic plutonic suites, and lesser age peaks consistent with regional Neoarchean and Mesoarchean greenstone belts and Mesoarchean gneiss. The units have comparable zircon age populations; therefore we interpret a shared provenance from the La Grande and Minto subprovinces, suggesting that none of the metasedimentary units represent exotic accreted terranes. Mean ages of youngest LA-ICP-MS zircon age clusters range from 2716 to 2695 Ma, thus defining the maximum ages of deposition. ID-TIMS analyses of select youngest grains confirm the efficacy of the LA-ICP-MS constraints. Regional intrusive suites ranging from ca. 2710 to 2678 Ma further constrain deposition to a short time interval. Our detrital geochronology results are similar to all other Superior Province metasedimentary subprovinces, which consistently exhibit large proportion