Except for some paleobotanical-based estimates in the southern Rocky Mountains, for all regions and time periods paleoaltimetry data suggest that elevations were likely lower than or close to modern; this is consistent with geodynamic models and other constraints e. Temperature-based paleoaltimetry methodologies are challenging, but have advanced substantially in the last decade and have potential to help address these remaining questions. Multiple factors independent of elevation influence MAST, including short- e.
Additionally, climate variability on decadal to millennial time scales may be integrated differently depending on the resolution of the proxy, and seasonal bias may impact different proxy types and settings e.
Workers have addressed such complications in various ways; e. Feng and Poulsen used paleoclimate simulations of Eocene North America to make improved predictions of contemporaneous sea-level temperatures for Cordilleran floral sites. There have also been varied approaches to determining lapse-rates, such as applying the average modern global 5.
Paleoclimate models have advanced significantly since initial rates were proposed and demonstrate that significant error can be generated by applying linear modern lapse-rates to ancient climates and paleogeographies; model-mediated lapse-rates should be a key component of future temperature-based paleoaltimetry studies e.
Confidence and accuracy in paleobotanical temperature estimates also have improved significantly. Advances include new standardizations in leaf physiognomic methods e. Additionally, the number of available CP-region collections has increased; local and regional stratigraphy refinements have improved context and relationships between existing floras e.
Evaluation of carbonate diagenesis also has improved e. Quaternary lacustrine carbonates from southwest North America apparently record summer-biased temperature instead of MAST Huntington et al. However, this bias may not hold for the paleo-record, particularly under Cretaceous and early Paleogene greenhouse climates. These advances can be leveraged to refine temperature-based proxy reconstructions and expand their use in the CP region.
Additionally, there is opportunity to re-evaluate late-Cenozoic Bidahochi and Bouse Formation paleotemperatures Huntington et al. In all cases, we recommend using paleoclimate model-mediated lapse-rates and sea-level corrections to minimize uncertainty and align methods for extrapolating temperature to elevation.
Our analysis suggests that temperature-based paleoaltimetry methods are key to refining CP paleoelevation, with implications for understanding uplift mechanisms and CR drainage evolution. EOH did much of the literature review, first drafts of writing, and compilation of datasets.
KH contributed to the writing and literature review on the Colorado Plateau, paleoaltimetry, and clumped isotopes. EGH contributed to the writing and literature review for paleobotanical methods. PSG drafted Figure 1 and contributed to the writing and literature review of river profile modelling. CB drafted Figure 2. All authors provided input on data analysis, interpretation, and writing. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
We also thank Laura Crossey, Cari Johnson, and Richard Ott for their insightful comments that greatly improved this manuscript. Allen, S. Aslan, A. Colorado: Geological Society of America , — Axelrod, D. The Late Oligocene Creede flora. Paleobiology 2, — Colorado: University of California Publications Geol. Google Scholar. Bailey, I. A Botanical index of Cretaceous and Tertiary Climates. Science 41, — Baumgartner, K. GSA Abstracts with Programs , Beard, L.
Bernasconi, S. Bird, P. Continental Delamination and the Colorado Plateau. Blasch, K. Ground Water 45, — Bondre, N. Botsyun, S. Earth Sci. Boyle, B. Higher Taxa as Paleoecological and. Breecker, D. America Bull. Burgener, L. Earth Planet.
Carrapa, B. Solid Earth , — Cather, S. Geosphere 8, — Chevalier, M. Change , 27— Cook, K. Earth Surf. Landforms 34 7 , — Crow, R. Geology 39, 27— Geosphere 15, — Geology 49, 7. Dansgaard, W. Stable Isotopes in Precipitation. Tellus 16, — Darling, A. Geosphere 11, — Map of Colorado Plateaus. Return to Physiographic Provinces. Explore This Park. Colorado Plateaus Province. This resulted in accumulation of thick interfingering nonmarine and marine sequences over most of the plateau.
The thick grey Mancos Shale, which is extensively exposed around the San Juan and Black Mesa Basins, is overlain by a series of eastward advancing sandy deltaic deposits.
It is with these deltas that much of the coal of the plateau is associated. The early Tertiary Laramide orogeny or disturbance separated Periods 4 and 5. It was during the Laramide event that many of the folds and minor faults of the Colorado Plateau were produced.
Uplift of the Grand Canyon section, refolding of the Zuni Uplift, the Defiance Uplift, and the Monument Valley Upwarp produced high plateaus but also isolated broad basins, like the Black Mesa Basin and the San Juan Basin, which continued to subside and receive sediments. The sediments were derived, in large part, from erosion of the uplifted Laramide blocks. The striking monoclines of the district are associated with this particular period of folding, which has affected all but the youngest rocks of the plateau.
Period 5 extends from the middle Tertiary nearly until modern times and is dominated by volcanic activity around the periphery of the plateau. Volcanic activity of the San Francisco Peak field, Mt. Taylor and the Datil section, the San Juan Mountains, the Valles Caldera near Los Alamos, and the numerous small intrusions of the Navajo and Hopi Buttes fields are part of this phase of geologic history.
Young lava flows in the Sunset Crater area and near Grants, New Mexico are typical of basaltic activity of the late phase of volcanic development of the region. Basin-and-Range-type block faulting has not materially affected the Colorado Plateau in most areas covered by the southern guidebook but such faulting has modified the eastern margin of the plateau across the guide route along the Rio Grande Depression.
Here a major graben developed in late Tertiary and Quaternary time. McMillan, M. History and causes of post-Laramide relief in the Rocky Mountain orogenic plateau. Flowers, R. CAS Google Scholar. Moucha, R. Geology 36 , — Lowry, A. Flexural rigidity of the Basin and Range-Colorado Plateau-Rocky Mountain transition from coherence analysis of gravity and topography. Lipman, P. Introduction to middle Tertiary Cordilleran volcanism — Magma sources and relations to regional tectonics.
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Wenrich, K. Spatial migration and compositional changes of Miocene-Quaternary magmatism in the western Grand Canyon. Garnetite xenoliths and mantle-water interactions below the Colorado Plateau, southwestern United States. English, J. Thermal modeling of the Laramide orogeny: testing the flat-slab subduction hypothesis. Earth Planet. Katz, R. A new parametrization of hydrous melting. Goes, S.
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