@misc{dutton1882tertiary1,
    author = "Dutton, C. E",
    title = "Tertiary History of the Grand Canyon District",
    year = "1882",
    howpublished = "Washington, D.C., Government Printing Office, v. 2, 264 p.; United States Geological Survey Mongraphs",
    note = "talkorigins\_source = {true}; raw\_reference = {Dutton, C. E., 1882, Tertiary History of the Grand Canyon District: Washington, D.C., Government Printing Office, v. 2, 264 p.; United States Geological Survey Mongraphs.}"
}

@techreport{sharp1940eparchean5,
    author = "Sharp, R. P",
    title = "Ep-Archean and Ep-Algonkian erosion surfaces, Grand Canyon, Arizona",
    year = "1940",
    howpublished = "Geological Society of America Bulletin, v. 51, p. 1235-1270",
    note = "talkorigins\_source = {true}; raw\_reference = {Sharp, R. P., 1940, Ep-Archean and Ep-Algonkian erosion surfaces, Grand Canyon, Arizona: Geological Society of America Bulletin, v. 51, p. 1235-1270.}"
}

@misc{mckee1945cambrian2,
    author = "McKee, E. D",
    title = "Cambrian History of the Grand Canyon Region",
    year = "1945",
    howpublished = "Washington, D.C., Carnegie Institute of Washington, 232 p.; Publication 563, Part I",
    note = "talkorigins\_source = {true}; raw\_reference = {McKee, E. D., 1945, Cambrian History of the Grand Canyon Region: Washington, D.C., Carnegie Institute of Washington, 232 p.; Publication 563, Part I.}"
}

@book{openalexw561344098,
    author = "Henry, Marguerite and Dennis, Wesley",
    title = "Brighty of the Grand Canyon",
    year = "1953",
    journal = "Bulletin of Miscellaneous Information (Royal Gardens Kew)",
    abstract = "Relates the adventures of a little burro who blazed trails through the Grand Canyon and met many famous people in the process",
    openalex = "W561344098"
}

@techreport{mckee1967evolution4,
    author = "McKee, E. H. and Wilson, R. F. and Breed, W. J. and Breed, C. S",
    title = "Evolution of the Colorado River in Arizona, 44 of Bulletin of the Museum of Northern Arizona",
    year = "1967",
    howpublished = "Phoenix, Arizona, Museum of Northern Arizona, 67 p",
    note = "talkorigins\_source = {true}; raw\_reference = {McKee, E. H., Wilson, R. F., Breed, W. J., and Breed, C. S., 1967, Evolution of the Colorado River in Arizona, 44 of Bulletin of the Museum of Northern Arizona: Phoenix, Arizona, Museum of Northern Arizona, 67 p.}"
}

@techreport{mckee1972pliocene3,
    author = "McKee, E. D. and McKee, E. H",
    title = "Pliocene uplift of the Grand Canyon region--time of drainage adjustment",
    year = "1972",
    howpublished = "Geological Society of America Bulletin, v. 83, p. 1923-1932",
    note = "talkorigins\_source = {true}; raw\_reference = {McKee, E. D., and McKee, E. H., 1972, Pliocene uplift of the Grand Canyon region--time of drainage adjustment: Geological Society of America Bulletin, v. 83, p. 1923-1932.}"
}

@article{doi102113gsecongeo8061722,
    author = "Wenrich, Karen J.",
    title = "Mineralization of breccia pipes in northern Arizona",
    year = "1985",
    journal = "Economic Geology",
    abstract = "The Paleozoic sedimentary rocks on the Colorado Plateau of northern Arizona are host to hundreds ofbreccia pipes. The uranium and copper deposits in these breccia pipes transgress formation boundaries from the Mississippian Redwall Limestone to the Triassic Chinle For-mation. They are not classic breccia pipes in that there is no volcanic rock associated with them in time or space. They are the result of solution-collapse within the Redwall Limestone and stoping of the overlying strata. The karst development in the Redwall Limestone began in the Mississippian and apparently either continued to the Triassic or was at least once again active during that time. The mineralization apparently occurred shortly thereafter, sometime during the Mesozoic. Mining activity in breccia pipes of the Grand Canyon region began during the nineteenth century and continues today with the operation of the Hack I, II, and III mines, although the exploited commodity has changed from Cu to U. Although small in size, these pipes contain samples with up to 55 percent U3Os and can yield ore averaging between 0.30 and•0.O0 percent U3Os. Mineralization at the surface commonly occurs within nodules and concretions associated with pyrite and goethite and along fractures, while the primary ore of the unoxidized zones is commonly within a comminuted sandstone matrix surrounding breccia fragments of overlying formations. The ore mineral is uraninite, although associated with it are sphalerite, galena, chalcopyrite, tennantite, millerite, siegenite, and/molybdenite. Some of the surface nodules are encrusted with malachite and are exceptionally enriched in Ag. Pyrite is abundant, and the organic carbon content of some rocks is high enough to suggest that it, along with the pyrite, may be a reductant for uranium. In contrast, it is possible, if uranium were transported as a bicarbonate or carbonate complex, that only a conduit of brecciated rock was necessary to release CO2, thus disrupting the equilibrium and allowing uraninite to precipitate. An",
    url = "https://doi.org/10.2113/gsecongeo.80.6.1722",
    doi = "10.2113/gsecongeo.80.6.1722",
    openalex = "W2070004880"
}

@article{doi101007bf01988374,
    author = "Meyer, A and Landais, P. and Brosse, E. and Pagel, Maurice and Carisey, J. C. and Krewdl, D.",
    title = "Thermal history of the Permian formations from the Breccia Pipes area (Grand Canyon region, Arizona)",
    year = "1989",
    journal = "International Journal of Earth Sciences",
    url = "https://doi.org/10.1007/bf01988374",
    doi = "10.1007/bf01988374",
    openalex = "W1963967348",
    references = "doi101007bf00413350, doi1010160012821x78900717, doi101029jz068i016p04847, doi101038327052a0, doi1010970001069419650700000019, doi1013062f9193d216ce11d78645000102c1865d, doi1015159781501508271, doi102516ogst1975026, doi102516ogst1985035, openalexw2727055235"
}

@incollection{doi101029ft115p0117,
    author = "Reynolds, Mitchell W. and Palacas, James G. and Elston, Donald P.",
    title = "Potential petroleum source rocks in the Late Proterozoic Chuar Group, Grand Canyon, Arizona",
    year = "1989",
    booktitle = "American Geophysical Union eBooks",
    url = "https://doi.org/10.1029/ft115p0117",
    doi = "10.1029/ft115p0117",
    openalex = "W1550270594"
}

@article{meyer1989thermal,
    author = "Meyer, A. J. and Landais, P. and Brosse, E. and Pagel, M. and Carisey, J. C. and Krewdl, D.",
    title = "Thermal history of the Permian formations from the Breccia Pipes area (Grand Canyon region, Arizona)",
    year = "1989",
    journal = "Geologische Rundschau",
    url = "https://doi.org/10.1007/bf01988374",
    doi = "10.1007/bf01988374",
    number = "1",
    openalex = "W1963967348",
    pages = "427-438",
    volume = "78",
    references = "doi101007bf00413350, doi1010160012821x78900717, doi101029jz068i016p04847, doi101038327052a0, doi1010970001069419650700000019, doi1013062f9193d216ce11d78645000102c1865d, doi1015159781501508271, doi102516ogst1975026, doi102516ogst1985035, openalexw2727055235"
}

@article{doi10102990jb01978,
    author = "Elston, Donald P. and Young, R. A.",
    title = "Cretaceous‐Eocene (Laramide) landscape development and Oligocene‐Pliocene drainage reorganization of transition zone and Colorado Plateau, Arizona",
    year = "1991",
    journal = "Journal of Geophysical Research Atmospheres",
    abstract = "Landscape development of central and northern Arizona can no longer be ascribed mainly to events of Miocene and Pliocene age. New information on the age and distribution of older Cenozoic deposits has led to the recognition of a regional Cretaceous‐Paleocene(?) surface of erosion that conforms to major elements of the present topography and to the recognition that a formerly thick deposit of gravel accumulated on this regional surface of erosion. These relations cast new light on the history of evolution of the landscape and indicate a much greater age for the main landscape elements and a more complicated and prolonged history of erosion and deposition than has been previously supposed. The timing of events postulated for development of drainage on the Colorado Plateau can now be compared and partly reconciled with events recognized in the adjacent closely related Mountain Region (Transition Zone) of central Arizona. As a consequence of Late Cretaceous‐Paleocene (Laramide) compression, central and northern Arizona underwent at least 1200 m of uplift, documented by paleochannels cut into erosionally truncated Paleozoic strata on the Hualapai Plateau of the southwestern Colorado Plateau. During this time, a highly irregular erosion surface was developed on Proterozoic rocks across the Transition Zone south of the Mogollon Rim, the scarp of the Mogollon Rim was eroded to its present height (600–900 m), and an extensive stripped surface was developed on resistant upper Paleozoic strata north of the rim. Deposition of several hundred meters of Paleocene‐Eocene “Rim gravels” derived from highlands south and west of the region followed, covering much of the Cretaceous‐Paleocene erosion surface. Nearly complete burial of the rim is suggested by the distribution of remnants of the Rim gravels across the erosional scarps and on high plateau areas north of the rim. A second increment of uplift, apparently occurring in late Eocene time and apparently recorded by a series of fission track cooling ages from the Marble and Grand canyons, is inferred to have been responsible for ending deposition of the Rim gravels, for initiating differential uplift of contemporaneous deposits (Canaan Peak and Claron formations) to their positions in the high plateaus of central Utah, and for causing the drainage reorganization required to explain the extensive removal of Rim gravels from much of the region. A southerly flowing ancestral Verde River related to the drainage reorganization removed much of the older gravel cover from the Transition Zone of central Arizona, resulting in a younger regional erosion surface having 600–900 m of relief, a surface closely approximating the Cretaceous‐Paleocene erosion surface. Late Oligocene and early Miocene rocks locally rest unconformably on remnants of Rim gravels in the Transition Zone, indicating that the second episode of regional erosion had been completed by late Oligocene time. North of the Mogollon Rim, a west flowing(?) ancestral Colorado River is inferred to have become established on the Rim gravels, draining the interior parts of the Colorado Plateau and transporting detritus off the plateau. Exhumation of the Mogollon Rim and development of 600–900 m of topographic relief in the Transition Zone by an ancestral Verde River system suggests the potential for a comparable, coeval entrenchment of an ancestral Colorado River in Paleozoic strata north of the Mogollon Rim. Regional extension and volcanic activity ensued in late Oligocene to Pliocene time. The Oligocene erosion surface in the extensional basins of central Arizona became largely concealed by Miocene and Pliocene deposits as the Neogene climate became drier. In late Miocene and Pliocene time, perennial streams appear to have been lacking, transport of detritus appears to have been principally by flash flooding, little or no detritus appears to have been removed from the region, and much of the precipitation presumably moved by groundwater flow through the deposits of aggradation. A coeval episode of aggradation in the Grand Canyon is suggested by deposits that appear to have once choked much of the canyon. If this event parallels the episode of late Miocene and Pliocene aggradation recorded east, south, and west of the Grand Canyon, the Colorado River could have been incised to its present level by late Miocene time. A return to wetter conditions in late Pliocene time presumably was responsible for renewed erosion and reexcavation of older drainages and basins. An understanding of this Tertiary structural, erosional, and depositional history can be important for the geological analysis of geophysical transects across the region.",
    url = "https://doi.org/10.1029/90jb01978",
    doi = "10.1029/90jb01978",
    openalex = "W2046565965",
    references = "doi1011300016760619748583pstibo20co2, doi101130001676061978891745eamcda20co2, doi101130001676061985961407cg20co2, doi101130001676061985961419acajg20co2, doi1011300016760619881001023papsol23co2, doi101130gsab471393, doi101130mem144p45, doi101130mem151p215, doi101130mem151p355, doi101306m41456c20"
}

@article{doi10102990jb02257,
    author = "Hillhouse, John W. and Wells, Ray E.",
    title = "Magnetic fabric, flow directions, and source area of the Lower Miocene Peach Springs Tuff in Arizona, California, and Nevada",
    year = "1991",
    journal = "Journal of Geophysical Research Atmospheres",
    abstract = "We have used anisotropy of magnetic susceptibility (AMS) to define the flow fabric and possible source area of the Peach Springs Tuff, a widespread rhyolitic ash flow tuff in the Mojave Desert and Great Basin of California, Arizona, and Nevada. The tuff is an important stratigraphic marker from the Colorado Plateau to Barstow, California, a distance of 350 km; however, the location of its source caldera is unknown. Dated at 18.5 Ma by 40 Ar/ 39 Ar, the tuff erupted during the early stages of Miocene extension along the lower Colorado River. The thicker accumulations (>100 m) occur at Kingman, Arizona, and in the Piute Mountains, California, on opposite sides of the Colorado River extensional corridor. Our AMS studies produced well‐defined magnetic lineations in 30 of 42 sites distributed throughout the tuff. Typical ratios of the principal AMS axes are 1.01 for the magnetic lineation (k max / k int) and 1.02 for the foliation (k int / k min); the bulk magnetic susceptibility of the Peach Springs Tuff averages 2.0×10 −3 in the SI unit system. The subhorizontal lineations, which presumably parallel the flow directions, form a pattern radiating outward from the approximate center of the outcrop area. Magnetic foliations define an imbrication that generally dips away from the distal margins and toward the center of the outcrop of the tuff. The lineation and imbrication indicate a source region near the southern tip of Nevada. Defining the best intersection of the AMS lineations required restoration of major extension, strike‐slip faulting, and associated tectonic rotation in the disrupted tuff. The optimum intersection of magnetic lineations lies in the southern Black Mountains of Arizona on the eastern side of the Colorado River extensional corridor. No caldera structures are known from that area, but the area contains thick sections of the Peach Springs Tuff above a silicic volcanic center. The caldera may be buried under younger deposits in the Mohave Valley of Arizona. Tertiary granite in the Newberry Mountains may represent a deeper level of the Peach Springs Tuff vent that has been exhumed by detachment faulting.",
    url = "https://doi.org/10.1029/90jb02257",
    doi = "10.1029/90jb02257",
    openalex = "W2045597907",
    references = "doi1011300016760619748583pstibo20co2"
}

@book{openalexw2123126779,
    author = "Sheridan, Thomas E.",
    title = "Arizona: A History",
    year = "1995",
    abstract = "Hailed as a model state history thanks to Thomas E. Sheridan's thoughtful analysis and lively interpretation of the people and events shaping the Grand Canyon State, has become a standard in the field. Now, just in time for Arizona's centennial, Sheridan has revised and expanded this already top-tier state history to incorporate events and changes that have taken place in recent years. Addressing contemporary issues like land use, water rights, dramatic population increases, suburban sprawl, and the US-Mexico border, the new material makes the book more essential than ever. It successfully places the forty-eighth state's history within the context of national and global events. No other book on Arizona history is as integrative or comprehensive. From stone spear points more than 10,000 years old to the boom and bust of the housing market in the first decade of this century, Arizona: A History explores the ways in which Native Americans, Hispanics, African Americans, Asians, and Anglos have inhabited and exploited Arizona. Sheridan, a life-long resident of the state, puts forth new ideas about what a history should be, embracing a holistic view of the region and shattering the artificial line between prehistory and history. Other works on Arizona's history focus on government, business, or natural resources, but this is the only book to meld the ethnic and cultural complexities of the state's history into the main flow of the story. A must read for anyone interested in Arizona's past or present, this extensive revision of the classic work will appeal to students, scholars, and general readers alike.",
    url = "https://openalex.org/W2123126779",
    openalex = "W2123126779"
}

@article{doi101093isle62229,
    author = "Huser, Verne",
    title = "How the Canyon Became Grand: A Short History",
    year = "1999",
    journal = "ISLE Interdisciplinary Studies in Literature and Environment",
    abstract = "How the Canyon Became Grand: A Short History Get access How The Canyon Became Grand: A Short History. Stephen J. Pyne. New York: Viking, 1998. 200 pp. Cloth $24.95. Paper $12.95. Verne Huser Verne Huser Albuquerque Academy Search for other works by this author on: Oxford Academic Google Scholar ISLE: Interdisciplinary Studies in Literature and Environment, Volume 6, Issue 2, Summer 1999, Page 229, https://doi.org/10.1093/isle/6.2.229 Published: 01 July 1999",
    url = "https://doi.org/10.1093/isle/6.2.229",
    doi = "10.1093/isle/6.2.229",
    openalex = "W2069676717"
}

@article{doi1023073985313,
    author = "Aton, James M.",
    title = "How the Canyon Became Grand: A Short History. By Stephen J. Pyne. New York: Viking, 1998. xviii + 199 pp. Illustrations, maps, figures, notes, bibliography, index. $24.95",
    year = "1999",
    journal = "Environmental History",
    url = "https://doi.org/10.2307/3985313",
    doi = "10.2307/3985313",
    openalex = "W1966340725"
}

@article{doi1010291999wr900285,
    author = "Topping, David J. and Rubin, David M. and Vierra, L. E.",
    title = "Colorado River sediment transport: 1. Natural sediment supply limitation and the influence of Glen Canyon Dam",
    year = "2000",
    journal = "Water Resources Research",
    abstract = "Analyses of flow, sediment‐transport, bed‐topographic, and sedimentologic data suggest that before the closure of Glen Canyon Dam in 1963, the Colorado River in Marble and Grand Canyons was annually supply‐limited with respect to fine sediment (i.e., sand and finer material). Furthermore, these analyses suggest that the predam river in Glen Canyon was not supply‐limited to the same degree and that the degree of annual supply limitation increased near the head of Marble Canyon. The predam Colorado River in Grand Canyon displays evidence of four effects of supply limitation: (1) seasonal hysteresis in sediment concentration, (2) seasonal hysteresis in sediment grain size coupled to the seasonal hysteresis in sediment concentration, (3) production of inversely graded flood deposits, and (4∥ development or modification of a lag between the time of a flood peak and the time of either maximum or minimum (depending on reach geometry) bed elevation. Analyses of sediment budgets provide additional support for the interpretation that the predam river was annually supply‐limited with respect to fine sediment, but it was not supply‐limited with respect to fine sediment during all seasons. In the average predam year, sand would accumulate and be stored in Marble Canyon and upper Grand Canyon for 9 months of the year (from July through March) when flows were dominantly below 200–300 m 3 /s; this stored sand was then eroded during April through June when flows were typically higher. After closure of Glen Canyon Dam, because of the large magnitudes of the uncertainties in the sediment budget, no season of substantial sand accumulation is evident. Because most flows in the postdam river exceed 200–300 m 3 /s, substantial sand accumulation in the postdam river is unlikely.",
    url = "https://doi.org/10.1029/1999wr900285",
    doi = "10.1029/1999wr900285",
    openalex = "W2090163816",
    references = "doi101086628592"
}

@article{doi1010292002eo000191,
    author = "Rubin, David M. and Topping, David J. and Schmidt, John C. and Hazel, Joe and Kaplinski, Matt and Melis, Theodore S.",
    title = "Recent sediment studies refute Glen Canyon Dam Hypothesis",
    year = "2002",
    journal = "Eos",
    abstract = "Recent studies of sedimentology hydrology, and geomorphology indicate that releases from Glen Canyon Dam are continuing to erode sandbars and beaches in the Colorado River in Grand Canyon National Park, despite attempts to restore these resources. The current strategy for dam operations is based on the hypothesis that sand supplied by tributaries of the Colorado River downstream from the dam will accumulate in the channel during normal dam operations and remain available for restoration floods. Recent work has shown that this hypothesis is false, and that tributary sand inputs are exported downstream rapidly typically within weeks or months under the current flow regime.",
    url = "https://doi.org/10.1029/2002eo000191",
    doi = "10.1029/2002eo000191",
    openalex = "W2072169391"
}

@article{doi101002esp1286,
    author = "Pederson, Joel L. and Petersen, Paul A. and Dierker, Jennifer L.",
    title = "Gullying and erosion control at archaeological sites in Grand Canyon, Arizona",
    year = "2006",
    journal = "Earth Surface Processes and Landforms",
    url = "https://doi.org/10.1002/esp.1286",
    doi = "10.1002/esp.1286",
    openalex = "W1998148274"
}

@article{doi101016jendeavour200607002,
    author = "Wills, John",
    title = "Brighty, donkeys and conservation in the Grand Canyon.",
    year = "2006",
    journal = "Endeavour",
    abstract = {The Grand Canyon is a vast place. It is almost incomprehensible in size. And yet it can also seem strangely crowded. Millions of tourists flock to the Grand Canyon in northern Arizona every year. In 1999, almost 5 million people visited, the highest figure in Canyon history. And each one of them expected to see a wild, free and untrammelled landscape. Despite the obvious natural resources, this expectation has proved anything but easy to satisfy. The US National Park Service (NPS), responsible for the management of most large North American parks (along with several historic sites and museums), has struggled to make or keep the canyon "grand". Park rangers have grappled with a multitude of issues during the past century, including automobile congestion, drying of the Colorado River and uranium mining inside the park. Conservation has posed a unique set of challenges. On a fundamental level, "restoring" the Grand Canyon to its "original" wilderness setting has proved intensely problematic. In the field of wildlife management, restoring the Canyon to its pre-Columbian splendour has entailed some tough decisions--none more so than a 1976 plan to eliminate a sizeable population of feral burros (wild donkeys) roaming the preserve, animals classified as exotics by the NPS.},
    url = "https://pubmed.ncbi.nlm.nih.gov/16904748/",
    doi = "10.1016/j.endeavour.2006.07.002",
    openalex = "W2090006369",
    pmid = "16904748",
    references = "doi101093isle62229, doi1023073985313, doi105860choice275771, openalexw1520549531, openalexw3034618764, openalexw561344098"
}

@article{doi101130b262311,
    author = "Flowers, Rebecca M. and Wernicke, Brian P. and Farley, Kenneth A.",
    title = "Unroofing, incision, and uplift history of the southwestern Colorado Plateau from apatite (U-Th)/He thermochronometry",
    year = "2008",
    journal = "Geological Society of America Bulletin",
    abstract = "The source of buoyancy for the uplift of cratonic plateaus is a fundamental question in continental dynamics. The \textasciitilde 1.9 km uplift of the Colorado Plateau since the Late Cretaceous is a prime example of this problem. We used apatite (U-Th)/He thermochronometry (230 analyses; 36 samples) to provide the first single-system, regional-scale proxy for the unroofing history of the southwestern quadrant of the plateau. The results confirm overall southwest to northeast unroofing, from plateau margin to plateau interior. A single phase of unroofing along the plateau margin in Late Cretaceous to Early Tertiary (Sevier- Laramide) time contrasts with multiphase unroofing of the southwestern plateau interior in Early and mid- to Late Tertiary time. The Early Cretaceous was characterized by northeastward tilting and regional erosion, followed by aggradation of ≥1500 m of Upper Cretaceous sediments along the eroded plateau margin. Sevier-Laramide denudation affected the entire southwestern plateau, was concentrated along the plateau margin, and migrated from northwest to southeast. Following a period of relative stability of the landscape from ca. 50–30 Ma, significant unroofing of the southwestern plateau interior occurred between ca. 28 and 16 Ma. Additional denudation north of the Grand Canyon took place in latest Tertiary time. Mid-Tertiary dates from the Grand Canyon basement at the bottom of the Upper Granite Gorge limit significant incision of the modern Grand Canyon below the Kaibab surface to 1500 m difference in vertical structural position. If these models are correct, they indicate that a “proto–Grand Canyon” of kilometer-scale depth had incised post-Paleozoic strata by the Early Eocene. Evidence for kilometer-scale mid-Tertiary relief in northeast-fl owing drainages along the plateau margin, as well as the mid-Tertiary episode of plateau interior unroofing, imply that the southwestern plateau interior had attained substantial elevation by at least 25–20 Ma, if not much earlier. These observations are inconsistent with any model calling for exclusively Late Tertiary uplift of the southwestern plateau. Sevier-Laramide plateau surface uplift and incision thus result from one or more processes that enhanced the buoyancy of the plateau lithosphere, expanding the Cordillera’s orogenic highlands into its low-standing cratonic foreland. The onset of the Laramide slab’s demise at ca. 40 Ma and the major pulse of extension in the Basin and Range from ca. 16–10 Ma appear to have had little influence on the denudation history of the southwestern plateau. In contrast, the post-Laramide unroofing episodes may be explained by drainage adjustments induced by rift-related lowering of regions adjacent to the plateau, without the need to otherwise modify the plateau lithosphere. Our data do not preclude a large component of post–Early Eocene elevation gain (or the geodynamic mechanisms it may imply), but they do point toward Laramide-age buoyancy sources as the initial cause of significant surface uplift, ending more than 500 m.y. of residence near sea level.",
    url = "https://doi.org/10.1130/b26231.1",
    doi = "10.1130/b26231.1",
    openalex = "W2144649209",
    references = "doi101016jepsl200607028, doi101016s0009254198000242, doi1010291999jb900348, doi10102990jb01978, doi101029jb084ib13p07561, doi101038270403a0, doi101098rsta19880089, doi101130001676061978891745eamcda20co2, doi1011300091761319900181173suuora23co2, doi1011300091761319950230987plrotf23co2, doi102138rmg20055811, doi10274700206814457575"
}

@article{doi101130g25032a1,
    author = "Karlstrom, Karl E. and Crow, Ryan and Crossey, Laura J. and Coblentz, David and van Wijk, Jolante",
    title = "Model for tectonically driven incision of the younger than 6 Ma Grand Canyon",
    year = "2008",
    journal = "Geology",
    url = "https://doi.org/10.1130/g25032a.1",
    doi = "10.1130/g25032a.1",
    openalex = "W1992299314"
}

@article{doi101130b302741,
    author = "Wernicke, Brian P.",
    title = "The California River and its role in carving Grand Canyon",
    year = "2011",
    journal = "Geological Society of America Bulletin",
    abstract = "Recently published thermochronological and paleoelevation studies in the Grand Canyon region, combined with sedimentary provenance data in both the coastal and interior portions of the North American Cordillera, place important new constraints on the paleohydrological evolution of the southwestern United States. Review and synthesis of these data lead to an interpretation where incision of a large canyon from a plain of low elevation and relief to a canyon of roughly the length and depth of modern Grand Canyon occurred primarily in Campanian time (80–70 Ma). Incision was accomplished by a main-stem, NE-flowing antecedent river with headwaters on the NE slope of the North American Cordillera in California, referred to herein after its source region as the California River. At this time, the river had cut to within a few hundred meters of its modern erosion level in western Grand Canyon, and to the level of Lower Mesozoic strata in eastern Grand Canyon. Subsequent collapse of the headwaters region into a continental borderland and coeval uplift of the Cordilleran foreland during the Laramide orogeny reversed the river's course by Paleogene time. After reversal, its terminus lay near its former source regions in what is now the Western Transverse Ranges and Salinian terrane. Its headwaters lay in the ancient Mojave/Mogollon Highlands region of Arizona and eastern California, apparently reaching as far northeast as the eastern Grand Canyon region. This system is herein referred to after its source region as the Arizona River. From Paleogene through late Miocene time, the interior of the Colorado Plateau was a closed basin separated from the Arizona River drainage by an asymmetrical divide in the Lees Ferry–Glen Canyon area, with a steep SW flank and gently sloping NE flank that drained into large interior lakes, fed primarily by Cordilleran/Rocky Mountain sources to the north and west, and by recycled California River detritus shed from Laramide uplifts on the plateau. By Oligocene time, the lakes had largely dried up and were replaced by ergs. By mid-Miocene time, a pulse of unroofing had lowered the erosion level of eastern Grand Canyon to within a few hundred meters of its present level, and the Arizona River drainage below modern Grand Canyon was deranged by extensional tectonism, cutting off the supply of interior detritus to the coast. Increasing moisture in the Rocky Mountains in late Miocene time reinvigorated fluviolacustrine aggradation NE of the asymmetrical divide, which was finally overtopped between 6 and 5 Ma, lowering base level in the interior of the plateau by 1500 m. This event reintegrated the former Arizona drainage system through a cascade of spillover events through Basin and Range valleys, for the first time connecting sediment sources in Colorado with the coast. This event, combined with the intensification of summer rainfall as the Gulf of California opened, increased the sediment yield through Grand Canyon by perhaps two orders of magnitude from its Miocene nadir, giving birth to the modern subcontinental-scale Colorado River drainage system. The Colorado River has thus played a major role in unroofing the interior of the Colorado Plateau, but was not an important factor in the excavation of Grand Canyon.",
    url = "https://doi.org/10.1130/b30274.1",
    doi = "10.1130/b30274.1",
    openalex = "W2098230053",
    references = "doi1010160168962286900746, doi1010160168962287900571, doi101016jgca200901015, doi1010291999jb900348, doi10102990jb01978, doi10108000206819809465216, doi101126science1059412, doi101130001676061978891745eamcda20co2, doi101130ges001221, doi101130gsab471393, doi102138am19990903, doi1023071774538, doi102475ajs3042105, openalexw2002729176"
}

@article{doi1010292012tc003107,
    author = "Roberts, G.G. and White, Nicky and Martin‐Brandis, G. L. and Crosby, Alistair",
    title = "An uplift history of the Colorado Plateau and its surroundings from inverse modeling of longitudinal river profiles",
    year = "2012",
    journal = "Tectonics",
    abstract = "It is generally agreed that a region encompassing the Colorado Plateau has been uplifted by sub‐crustal processes. Admittance calculations, tomographic studies and receiver function analyses suggest that dynamic support is generated by some combination of convective upwelling and lithospheric thickness changes. Notwithstanding advances in our understanding of present‐day setting, uplift rate histories are poorly constrained and debated: an improved history will aid discrimination between proposed models. Here, we show that a regional uplift rate history can be obtained by inverting longitudinal river profiles. We assume that the shape of a river profile is controlled by uplift rate and moderated by erosion. In our model, uplift rate is allowed to vary smoothly as a function of space and time, upstream drainage area is invariant with time. Simultaneous inversion of river profiles from the Colorado, Rio Grande, Columbia and Mississippi catchments shows that three phases of regional uplift occurred. The first phase occurred between 80 and 50 Myrs, when ∼1 km of uplift was generated at a rate of ∼0.03 mm/yr. A second phase occurred between 35 and 15 Myrs, when ∼1.5 km of uplift was generated at a faster rate of ∼0.06 mm/yr. A final phase of uplift commenced ∼5 Myrs ago. These distinct phases of Late Cretaceous and Oligocene uplift are corroborated by stratigraphic considerations, by thermochronometric data, and by stratigraphic evidence of periodic clastic efflux delivered into the Gulf of Mexico. An episodic uplift history is consistent with staged removal of thick lithospheric mantle beneath a large region, which is currently centered on Yellowstone.",
    url = "https://doi.org/10.1029/2012tc003107",
    doi = "10.1029/2012tc003107",
    openalex = "W1525355917",
    references = "doi101016037847549390043t, doi1010291999jb900120, doi1010292005rg000183, doi10102990jb01978, doi10102997jb02122, doi101029jb084ib13p07561, doi101111j1365246x201004884x, doi101126science1116412, doi1011300091761320010291087sarsco20co2, doi101130l1501, doi101146annurevearth32101802120356, doi10119011442837"
}

@article{doi101038ngeo2065,
    author = "Karlstrom, Karl E. and Lee, John P. and Kelley, Shari A. and Crow, Ryan and Crossey, Laura J. and Young, R. A. and Lazear, Greg and Beard, L. Sue and Ricketts, Jason W. and Fox, Matthew and Shuster, David L.",
    title = "Formation of the Grand Canyon 5 to 6 million years ago through integration of older palaeocanyons",
    year = "2014",
    journal = "Nature Geoscience",
    url = "https://doi.org/10.1038/ngeo2065",
    doi = "10.1038/ngeo2065",
    openalex = "W2148350085",
    references = "doi101130b302741, doi101130l1501"
}

@article{doi1010022015jg002991,
    author = "Sankey, Joel B. and Ralston, Barbara E. and Grams, Paul E. and Schmidt, John C. and Cagney, Laura E.",
    title = "Riparian vegetation, Colorado River, and climate: Five decades of spatiotemporal dynamics in the Grand Canyon with river regulation",
    year = "2015",
    journal = "Journal of Geophysical Research Biogeosciences",
    abstract = "Abstract Documentation of the interacting effects of river regulation and climate on riparian vegetation has typically been limited to small segments of rivers or focused on individual plant species. We examine spatiotemporal variability in riparian vegetation for the Colorado River in Grand Canyon relative to river regulation and climate, over the five decades since completion of the upstream Glen Canyon Dam in 1963. Long‐term changes along this highly modified, large segment of the river provide insights for management of similar riparian ecosystems around the world. We analyze vegetation extent based on maps and imagery from eight dates between 1965 and 2009, coupled with the instantaneous hydrograph for the entire period. Analysis confirms a net increase in vegetated area since completion of the dam. Magnitude and timing of such vegetation changes are river stage‐dependent. Vegetation expansion is coincident with inundation frequency changes and is unlikely to occur for time periods when inundation frequency exceeds approximately 5\%. Vegetation expansion at lower zones of the riparian area is greater during the periods with lower peak and higher base flows, while vegetation at higher zones couples with precipitation patterns and decreases during drought. Short pulses of high flow, such as the controlled floods of the Colorado River in 1996, 2004, and 2008, do not keep vegetation from expanding onto bare sand habitat. Management intended to promote resilience of riparian vegetation must contend with communities that are sensitive to the interacting effects of altered flood regimes and water availability from river and precipitation.",
    url = "https://doi.org/10.1002/2015jg002991",
    doi = "10.1002/2015jg002991",
    openalex = "W2104122334",
    references = "doi103133pp1677"
}

@article{doi1010292015eo030349,
    author = "Grams, Paul E. and Schmidt, John C. and Wright, Scott A. and Topping, David J. and Melis, Theodore S. and Rubin, David M.",
    title = "Building Sandbars in the Grand Canyon",
    year = "2015",
    journal = "Eos",
    abstract = "Annual controlled floods from one of America's largest dams are rebuilding the sandbars of the iconic Colorado River.",
    url = "https://doi.org/10.1029/2015eo030349",
    doi = "10.1029/2015eo030349",
    openalex = "W2227202515"
}

@article{doi1010022016tc004166,
    author = "Hill, Carol A. and Polyak, Victor J. and Asmerom, Yemane and Provencio, Paula P.",
    title = "Constraints on a Late Cretaceous uplift, denudation, and incision of the Grand Canyon region, southwestern Colorado Plateau, USA, from U‐Pb dating of lacustrine limestone",
    year = "2016",
    journal = "Tectonics",
    abstract = "The uplift and denudation of the Colorado Plateau is important in reconstructing the geomorphic and tectonic evolution of western North America. A Late Cretaceous (64 ± 2 Ma) U-Pb age for the Long Point limestone on the Coconino Plateau, which overlies a regional erosional surface developed on Permo-Triassic formations, supports unroofing of the Coconino Plateau part of Grand Canyon by that time. U-Pb analyses of three separate outcrops of this limestone gave ages of 64.0 ± 0.7, 60.5 ± 4.6, and 66.3 ± 3.9 Ma, which dates are older than a fossil-based, early Eocene age. Samples of the Long Point limestone were dated using the isotope dilution isochron method on well-preserved carbonates having high-uranium and low-lead concentrations. Our U-Pb ages on the Long Point limestone place important constraints on the (1) time of tectonic uplift of the southwestern Colorado Plateau and Kaibab arch, (2) time of denudation of the Coconino Plateau, and (3) Late Cretaceous models of paleocanyon incision west of, or across, the Kaibab arch. We propose that the age of the Long Point limestone, interbedded within the Music Mountain Formation in the Long Point area, represents a period of regional aggradation and a time of drainage blockage northward and eastward across the Kaibab arch, with possible diversion of northward drainage on the Coconino Plateau westward around the arch via a Laramide paleo-Grand Canyon.",
    url = "https://doi.org/10.1002/2016tc004166",
    doi = "10.1002/2016tc004166",
    openalex = "W2373476897",
    references = "doi1010292007rg000246, doi10102990jb01978, doi101029jb094ib07p09439, doi101038nature08052, doi101038nature10001, doi101038ngeo2065, doi101130001676061978891745eamcda20co2, doi101130b262311, doi101130b302741, doi101130g25032a1, doi101130g315911, doi102110jsr201151"
}

@article{doi101144sp4665,
    author = "Jones, C. and Springer, Abraham E. and Tobin, Benjamin W. and Zappitello, Sarah J. and Jones, Natalie A.",
    title = "Characterization and hydraulic behaviour of the complex karst of the Kaibab Plateau and Grand Canyon National Park, USA",
    year = "2017",
    journal = "Geological Society London Special Publications",
    abstract = "Abstract The Kaibab Plateau and Grand Canyon National Park in the USA contain both shallow and deep karst systems, which interact in ways that are not well known, although recent studies have allowed better interpretations of this unique system. Detailed characterization of sinkholes and their distribution on the surface using geographical information system and LiDAR data can be used to relate the infiltration points to the overall hydrogeological system. Flow paths through the deep regional geological structure were delineated using non-toxic fluorescent dyes. The flow characteristics of the coupled aquifer system were evaluated using hydrograph recession curve analysis via discharge data from Roaring Springs, the sole source of the water supply for the Grand Canyon National Park. The interactions between these coupled surface and deep karst systems are complex and challenging to understand. Although the surface karst behaves in much the same way as karst in other similar regions, the deep karst has a base flow recession coefficient an order of magnitude lower than many other karst aquifers throughout the world. Dye trace analysis reveals rapid, conduit-dominated flow that demonstrates fracture connectivity along faults between the surface and deep karst. An understanding of this coupled karst system will better inform aquifer management and research in other complex karst systems.",
    url = "https://doi.org/10.1144/sp466.5",
    doi = "10.1144/sp466.5",
    openalex = "W2768045385"
}

@article{doi101186s129320170047y,
    author = "Kenny, Ray",
    title = "A geochemical view into continental palaeotemperatures of the end-Permian using oxygen and hydrogen isotope composition of secondary silica in chert rubble breccia: Kaibab Formation, Grand Canyon (USA).",
    year = "2018",
    journal = "Geochemical transactions",
    abstract = "The upper carbonate member of the Kaibab Formation in northern Arizona (USA) was subaerially exposed during the end Permian and contains fractured and zoned chert rubble lag deposits typical of karst topography. The karst chert rubble has secondary (authigenic) silica precipitates suitable for estimating continental weathering temperatures during the end Permian karst event. New oxygen and hydrogen isotope ratios of secondary silica precipitates in the residual rubble breccia: (1) yield continental palaeotemperature estimates between 17 and 22 °C; and, (2) indicate that meteoric water played a role in the crystallization history of the secondary silica. The continental palaeotemperatures presented herein are broadly consistent with a global mean temperature estimate of 18.2 °C for the latest Permian derived from published climate system models. Few data sets are presently available that allow even approximate quantitative estimates of regional continental palaeotemperatures. These data provide a basis for better understanding the end Permian palaeoclimate at a seasonally-tropical latitude along the western shoreline of Pangaea.",
    url = "https://pmc.ncbi.nlm.nih.gov/articles/PMC5770344/",
    doi = "10.1186/s12932-017-0047-y",
    openalex = "W2783606095",
    pmcid = "PMC5770344",
    pmid = "29340852",
    references = "doi101016001670379090160m, doi101016jepsl200708020, doi101038367231a0, doi101038416076a, doi101126science1104323, doi101126science1213454, doi101126science2605108640, doi101126science27252651155, doi101126science2765310235, openalexw1498725839"
}

@article{openalexw3007818522,
    author = "Harlow, Abbie",
    title = {The Burro Evil": The Removal of Feral Burros from Grand Canyon National Park, 1924–1983},
    year = "2020",
    journal = "Project Muse (Johns Hopkins University)",
    openalex = "W3007818522",
    references = "doi101016jendeavour200607002"
}

@article{doi101016jejrh2023101461,
    author = "Beisner, Kimberly R. and Paretti, Nicholas V. and Jasmann, Jeramy R. and Barber, Larry B.",
    title = "Utilizing anthropogenic compounds and geochemical tracers to identify preferential structurally controlled groundwater pathways influencing springs in Grand Canyon National Park, Arizona, USA",
    year = "2023",
    journal = "Journal of Hydrology Regional Studies",
    abstract = "This study focuses on the Colorado River watershed in the area along the South Rim of the Grand Canyon. This study utilizes anthropogenic chemical tracers to investigate the fate of treated wastewater effluent discharged within Grand Canyon National Park. Anthropogenic chemical tracers were used to discern preferential structurally controlled pathways in a complex regional network of faults and fractures in which some are conduits and others barriers to flow. Previous investigations on water resources of Grand Canyon have suggested two different discharge locations (Garden Springs versus Monument Spring) for the treated wastewater discharged on the South Rim of Grand Canyon yet the presence of wastewater at the springs remained unstudied for decades. The treated wastewater from Grand Canyon Village is released into Bright Angel Wash that flows along the surface expression of the Bright Angel Fault and past the inferred intersection with the perpendicular Monument Fault. Multiple anthropogenic compounds (pharmaceuticals, per- and polyfluoroalkyl substances (PFAS), and elevated nitrate) were found in Bright Angel Wash and Monument Spring. Stable isotopic measurements at Monument Spring show depletion over time also suggesting contribution from a depleted stable isotopic source found in the treated wastewater. The anthropogenic tracers utilized in this study provide good insight to which geologic structures are conduits versus barriers to flow and can be useful in other fracture flow and karst settings.",
    url = "https://doi.org/10.1016/j.ejrh.2023.101461",
    doi = "10.1016/j.ejrh.2023.101461",
    openalex = "W4382752257"
}

@article{doi101016jjenvman2023118036,
    author = "Sankey, Joel B and East, Amy and Fairley, Helen C and Caster, Joshua and Dierker, Jennifer and Brennan, Ellen and Pilkington, Lonnie and Bransky, Nathaniel and Kasprak, Alan",
    title = "Archaeological sites in Grand Canyon National Park along the Colorado River are eroding owing to six decades of Glen Canyon Dam operations.",
    year = "2023",
    journal = "Journal of environmental management",
    abstract = "The archaeological record documenting human history in deserts is commonly concentrated along rivers in terraces or other landforms built by river sediment deposits. Today that record is at risk in many river valleys owing to human resource and infrastructure development activities, including the construction and operation of dams. We assessed the effects of the operations of Glen Canyon Dam - which, since its closure in 1963, has imposed drastic changes to flow, sediment supply and distribution, and riparian vegetation - on a population of 362 archaeological sites in the Colorado River corridor through Grand Canyon National Park, Arizona, USA. We leverage 50 years of evidence from aerial photographs and more than 30 years of field observations and measurements of archaeological-site topography and wind patterns to evaluate changes in the physical integrity of archaeological sites using two geomorphology-based site classification systems. We find that most archaeological sites are eroding; moreover, most are at increased risk of continuing to erode, due to six decades of operations of Glen Canyon Dam. Results show that the wind-driven (aeolian) supply of river-sourced sand, essential for covering archaeological sites and protecting them from erosion, has decreased for most sites since 1973 owing to effects of long-term dam operations on river sediment supply and riparian vegetation expansion on sandbars. Results show that the proportion of sites affected by erosion from gullies controlled by the local base-level of the Colorado River has increased since 2000. These changes to landscape processes affecting archaeological site integrity limit the ability of the National Park Service and Grand Canyon-affiliated Native American Tribes to achieve environmental management goals to maintain or improve site integrity in situ. We identify three environmental management opportunities that could be used to a greater extent to decrease the risk of erosion and increase the potential for in-situ preservation of archaeological sites. Environmental management opportunities are: 1) sediment-rich controlled river floods to increase the aeolian supply of river-sourced sand, 2) extended periods of low river flow to increase the aeolian supply of river-sourced sand, 3) the removal of riparian vegetation barriers to the aeolian transport of river-sourced sand.",
    url = "https://pubmed.ncbi.nlm.nih.gov/37182479/",
    doi = "10.1016/j.jenvman.2023.118036",
    openalex = "W4376253624",
    pmid = "37182479",
    references = "doi1010022015jg002991, doi101002esp1286, doi1010079783642334450, doi101016jgeomorph201210034, doi1010291999wr900285, doi1010292002eo000191, doi1010292015eo030349, doi101029gm089, doi101038ngeo2065, doi101093bioscibiw059"
}

@article{doi101016joregeorev2025106590,
    author = "Gosen, Bradley S. Van and Hall, Susan M. and Johnson, Craig A. and Benzel, William M.",
    title = "Solution-collapse breccia pipe uranium deposits of the southern Colorado Plateau, northwestern Arizona, USA",
    year = "2025",
    journal = "Ore Geology Reviews",
    abstract = "Schematic cross section of a uranium ore-bearing, solution-collapse breccia pipe of the Grand Canyon region of northwestern Arizona. • Uranium deposits within solution-collapse breccia pipes occur in northwest Arizona. • Uraninite is the ore mineral, intergrown with at least 20 base-metal sulfide minerals. • The sulfides contribute high concentrations of Fe, Cu, Co, As, Pb, Zn, Ni, and Ag. • Dissolved layers of gypsum may be the S source, which later reduced U from groundwaters. • Mineralized pipes formed where the gypsum units occur, outlining prospective regions. Some of the highest-grade uranium deposits in the United States occur in breccia pipes that formed by solution and collapse of sedimentary strata, which occur in the southern portion of the Colorado Plateau in northwestern Arizona. The host breccia pipes are up to 1200 m in vertical extent, average about 90 m in diameter, and can cross-cut strata from their base in the Mississippian Redwall Limestone to as stratigraphically high on some plateaus as the Triassic Chinle Formation. These uranium-base metal deposits are up to 600 m thick and formed within the breccia pipes where they transect the Permian Coconino Sandstone, Hermit Formation, and the Esplanade Sandstone. Of the hundreds of breccia pipes identified across this region, only a small percentage are known to contain mineralization. The main uranium ore mineral is uraninite that is intergrown with at least 20 base-metal sulfide minerals, which contribute Fe, Cu, Co, As, Pb, Zn, Ni, and Ag to the deposits. This study considered regional stratigraphy, sulfur isotope systematics, mineralogy, in situ dating, and compilation and analysis of previous work on the deposits. A comprehensive deposit model has not been published for these deposits. This analysis identified new additions to update the deposit model for these unusual, possibly unique deposits. Proposed modifications to the model include: (1) the source, mechanisms, timing of the base-metal sulfide mineral assemblages, and (2) the source, mechanism, and timing of the uranium mineralization. Sulfide and uranium deposition are shown to be separate mineralization events. The study proposes the possible role of gypsum as a source of sulfur for the sulfide minerals in the deposits. Groundwaters carrying uranium encountered the preexisting sulfides in breccia pipes, reducing the uranyl ions, and precipitating U oxide (as uraninite). Analysis of the regional stratigraphy recognized that numerous beds of gypsum are in the strata that lie only tens of meters above the breccia pipe deposits. In the breccia pipe region, if these stratigraphic units (Toroweap and Kaibab Formations) do not contain gypsum layers then the underlying pipes are not mineralized; where these Permian gypsum layers do occur, breccia pipes can host mineralization. This new understanding should be useful in identifying the prospective region for mineralized pipes.",
    url = "https://doi.org/10.1016/j.oregeorev.2025.106590",
    doi = "10.1016/j.oregeorev.2025.106590",
    openalex = "W4409291396",
    references = "doi101007bf01988374, doi101007s42461025011846, doi101016000925419090139x, doi101016jejrh2023101461, doi101016joregeorev2023105353, doi10113000167606196374609ieotoo20co2, doi101144sp4665, doi102113gsecongeo1053627, doi102113gsecongeo8061722, doi102475ajss51269198, doi105860choice352126, meyer1989thermal"
}