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The long-term (> 1 Ga) thermal histories of cratons are enigmatic, with geologic data providing only limited snapshots of their evolution. We use zircon (U-Th)/He (zircon He) thermochronology and age-composition correlations to understand the Proterozoic-Phanerozoic thermal history of Archean Wyoming province rocks exposed in the northern Laramide ranges of western North America. Zircon He ages from the Wind River Range (54 dates) and Bighorn Mountains (32 dates) show negative correlations with effective uranium (eU), a proxy for radiation damage. Zircon dates from the Bighorns are between 960 Ma (low-eU) and 20 Ma (high-eU) whereas samples from the Wind Rivers are between 582 Ma (low-eU) and 33 Ma (high-eU). We applied forward modeling using the zircon radiation damage and annealing model ZrDAAM to understand this highly variable dataset. A long-term t-T path that is consistent with the available geologic constraints successfully reproduced age-eU correlations. The best fit to the Wind Rivers data involves two phases of rapid cooling at 1800-1600 Ma and 900-700 Ma followed by slower cooling until 525 Ma. During the Phanerozoic, these samples were heated to maximum temperatures between 160-125°C prior to Laramide cooling to 50ºC between 60-40 Ma. Data from the Bighorn Mountains were successfully reproduced with a similar thermal history involving cooler Phanerozoic temperatures of ~115 °C and earlier Laramide cooling between 85-60 Ma. Our results indicate that age-eU correlations in zircon He datasets can be applied to extract long-term thermal histories that extend beyond the most recent cooling event. In addition, our results constrain the timing, magnitude and rates of cooling experienced by Archean Wyoming Province rocks between recognized deformation events, including the >1 Ga period represented by the regionally-extensive Great Unconformity. 1. Introduction Basement rocks of the Laramide ranges of northwestern Wyoming experienced a protracted thermal history involving multiple burial and exhumation episodes since their formation during the Archean. Geologic and geochronologic data indicate that prior to *Manuscript Clean (track changes accepted) Click here to view linked References their most recent exhumation in the Cenozoic and burial by several kilometers of sediment in the Paleozoic and Mesozoic, these rocks were affected by multiple Proterozoic tectonic events such as supercontinent assembly and rifting (e.g., Chamberlain et al. 2003; Marshak et al., 2000). However, specific constraints on the time-Temperature (t-T) history of the region remain enigmatic. Understanding the early Proterozoic-Mesozoic thermal history enables an integrated long-term history that could reveal previously undocumented events, including thermal maturation, cratonal stability, and orogenesis. Apatite fission track (AFT) and (U-Th)/He (apatite He) thermochronology has previously been used to resolve the thermal histories of cratons, typically over 10 8-year time scales (e.g.,

Craton cores far from plate boundaries have traditionally been viewed as stable features that experience minimal vertical motion over 100–1000 Ma time scales. Here we show that the Fennoscandian Shield in southeastern Sweden experienced several episodes of burial and exhumation from ~1800 Ma to the present. Apatite, titanite, and zircon (U‐Th)/He ages from surface samples and drill cores constrain the long‐term, low‐temperature history of the Laxemar region. Single grain titanite and zircon (U‐Th)/He ages are negatively correlated (104–838 Ma for zircon and 160–945 Ma for titanite) with effective uranium (eU = U + 0.235 × Th), a measurement proportional to radiation damage. Apatite ages are 102–258 Ma and are positively correlated with eU. These correlations are interpreted with damage‐diffusivity models, and the modeled zircon He age‐eU correlations constrain multiple episodes of heating and cooling from 1800 Ma to the present, which we interpret in the context of foreland basin systems related to the Neoproterozoic Sveconorwegian and Paleozoic Caledonian orogens. Inverse time‐temperature models constrain an average burial temperature of ~217°C during the Sveconorwegian, achieved between 944 Ma and 851 Ma, and ~154°C during the Caledonian, achieved between 366 Ma and 224 Ma. Subsequent cooling to near‐surface temperatures in both cases could be related to long‐term exhumation caused by either postorogenic collapse or mantle dynamics related to the final assembly of Rodinia and Pangaea. Our titanite He age‐eU correlations cannot currently be interpreted in the same fashion; however, this study represents one of the first examples of a damage‐diffusivity relationship in this system, which deserves further research attention.