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The package PbIso is a free and open R toolbox for commonly used calculations and plots of Pb–Pb isotope data and for generating Pb evolution models. In this paper, we review Pb isotope systematics and the calculations that are commonly used, such as model age, model source μ (238U/204Pb), time-integrated κ (232Th/238U), and initial Pb isotope ratios. These equations are implemented into R functions in the package PbIso. In addition, functions are provided for generating Pb evolution models, paleoisochrons, and isochrons. This allows users to apply calculations to their data in a straightforward way while providing transparency and flexibility of the calculations used. We have implemented some basic features of the PbIso package into an online shiny R application (see https://shereearmistead.github.io/software/pbiso), which makes it easy for users without any R experience to use these calculations with their own data and to generate plots. We have provided a case study from the Superior Province in Canada, showing how different Pb evolution models can be generated in PbIso and compared to Pb isotope data. [ABSTRACT FROM AUTHOR]

The Kivalliq Igneous Suite (1.77–1.73 Ga) includes the Nueltin Granite intrusions; gabbro and anorthosite intrusions; three swarms of mafic dykes; and basalt, rhyolite and pyroclastic rocks of the Pitz Formation (Wharton Group, middle Dubawnt Supergroup). It was emplaced in the reworked Archaean hinterland of the trans-Hudson orogen, in the central western Churchill Province (WCP) of the Canadian Shield. The Nueltin granites have field relations, mineral assemblages, and compositions typical of metaluminous to peraluminous, Proterozoic to Recent rapakivi granites, and the suite comprises a classic bimodal anorogenic province. Kivalliq rhyolites/granites were erupted/emplaced in a N–S band (the “Nueltin corridor”) about 700 km long and 300 km wide, with volcanic rocks and dykes concentrated at the north end and coarse plutonic rocks to the south. The McRae Lake dyke swarm originates among three prominent gabbro/anorthosite intrusions inside the corridor, and forms a narrow array extending a minimum of 600 km to the NE along the central axis of the WCP. Early mafic rocks (intrusions and some lavas, 1.77 Ga) had an alkali basalt parent, with subalkaline basalts (sills, dykes, and mafic enclaves) present at the peak time of granite emplacement (1.75 Ga). Average initial ɛ Nd of basaltic rocks at 1.75 Ga is −4.0, indicating a significant crustal component. Sm–Nd depleted mantle model ages of granites and rhyolites (average initial ɛ Nd = −8.7) range from 2.2 to 3 Ga, consistent with melted Archaean crust variably mixed with juvenile basalt. Metallogenic prospects of the Kivalliq Suite include U–Th–Zr–Y–REE enriched granite and syenite, epithermal Ag/Au at silicic centres (including mafic/felsic ring complexes), and Pb–Cu sulphides associated with mafic intrusions. Topaz rhyolites are present, but Sn-enriched rocks have not been observed. The Kivalliq Suite is one of about 15 prominent anorogenic provinces and dyke swarms which erupted within the Nuna supercontinent at ca. 1.75 Ga, and the thermal effects of the Kivalliq event are recorded in U–Pb and K–Ar data throughout most of the western Churchill Province. [ABSTRACT FROM AUTHOR]