Ian William Hillenbrand 2024 <div class="abstract-group "><div class="article-section__content en main"><p>Laurentia (ancestral North America) records nearly 4 billion years of crustal evolution. Here, a newly compiled continental-scale Pb isotopic database is used to evaluate the Precambrian crustal evolution of Laurentia. Pb model ages yield a 2.7 Ga peak, a 2.5–1.8 Ga minimum and 1.8–0.9 Ga continuum. Pb model ages yield thermochronometric data and track crustal growth via arc-related magmatism and accretionary orogenesis. Model<span>&nbsp;</span>²³²Th/²⁰⁴Pb and<span>&nbsp;</span>²³⁸U/²⁰⁴Pb broadly correlate with mapped crustal domains. More homogeneous and less radiogenic<span>&nbsp;</span>²³⁸U/²⁰⁴Pb and<span>&nbsp;</span>²³²Th/²³⁸U after 2.7 Ga suggests a shift to more juvenile sources, loss of early isotopic reservoirs and greater crustal reworking. U and Th are fractionated from Pb in Proterozoic orogens with abundant ferroan and anorthosite–mangerite–charnockite–granite(AMCG)-suite magmatism. This fractionation suggests the removal of Pb-rich lower crust, supporting petrogenetic models involving lithospheric foundering and magmatic underplating. Lithospheric thinning and associated magmatism may have contributed to high middle Proterozoic geothermal gradients.</p></div></div> application/pdf 10.1111/ter.12748 en Wiley Lead isotopes constrain Precambrian crustal architecture, thermal history, and lithospheric foundering in Laurentia article