Reassessing classic evidence for warm-based Cryogenian ice on the western Laurentian margin: The “striated pavement” of the Mineral Fork Formation, USA
Description
This dataset supports the following manuscript, available free of charge at https://www.sciencedirect.com/science/article/pii/S0301926821002734 : Vandyk, T.M., Kettler, C., Davies, B.J., Shields, G.A., Candy, I., Le Heron, D.P., 2021. Reassessing classic evidence for warm-based Cryogenian ice on the western Laurentian margin: The “striated pavement” of the Mineral Fork Formation, USA. Precambrian Research 363, 106345. https://doi.org/10.1016/j.precamres.2021.106345 Contents 1. Higher resolution versions of figures and supplementary figures. Please see https://doi.org/10.1016/j.precamres.2021.106345 for full descriptions of figures and supplementary figures. 2. Digital Elevation Model of "pavement": DEM S1: GeoTiff Digital Elevation Model of “pavement” used in Fig. 2; Spatial reference: NAD 1983 - UTM Zone 12N (EPSG::26912). 3. Movie files. Movie S1 and Movie S2 of the "pavement" and Mill B North Fork valley hosting the "pavement". Abstract Determining the extent and nature of ancient glacial deposits is fundamental to understanding Earth’s climate in the Cryogenian Period. Although the detailed study of sedimentary facies has allowed significant insights, it typically fails to produce high confidence interpretations for the past position of grounded ice, its thermal regime and flow direction, which are of fundamental importance to any glaciological reconstruction. When correctly identified, Cryogenian subglacially striated surfaces (pavements) unequivocally indicate grounded ice, a warm-based thermal regime and flow direction. However, they are globally rare and open to misinterpretation. Despite a discontinuous belt of Cryogenian strata, stretching thousands of kilometres from Alaska to California, the only purported Cryogenian pavements from the North American continent or the western margin of the Laurentian palaeocontinent occur in the Big Cottonwood Canyon area, Utah. We critically reappraise the only uncontested pavement from this area, presenting a detailed description derived from new high resolution photogrammetry and traditional field observations. These suggest that the purported pavement is unlikely to be a Cryogenian feature, but is instead a recent erosional phenomenon consistent with other structurally controlled features within the surrounding modern landscape. Our reinterpretation questions whether grounded Cryogenian ice reached the Utah – Idaho region and whether the lower reaches of the Mineral Fork Formation record glacially influenced deposition or non-glacial, rift-related sedimentation that transitions upwards into glacial conditions. Acknowledgements This work was supported by the Natural Environment Research Council [grant number NE/L002485/1] and awards to TMV from the International Association of Sedimentologists, the British Society for Geomorphology and Society for Sedimentary Geology (SEPM). We are most grateful to 3 anonymous reviewers, Marie Busfield, Nicholas Eyles and Maarten Krabbendam.