U.S. Geological Survey Open-File Report 2011–1210
A 2010 Colorado River symposium, held in Flagstaff, Arizona, involved 70 participants who engaged in intense debate about the origin and evolution of the Colorado River system. This symposium, built upon two previous decadal scientific meetings, focused on forging scientific consensus, where possible, while articulating continued controversies regarding the Cenozoic evolution of the Colorado River System and the landscapes of the Colorado Plateau–Rocky Mountain region that it drains. New developments involved hypotheses that Neogene mantle flow is driving plateau tilting and differential uplift and new and controversial hypotheses for the pre-6 Ma presence and evolution of ancestral rivers that may be important in the history and birth of the present Colorado River. There is a consensus that plateau tilt and uplift models must be tested with multidisciplinary studies involving differential incision studies and additional geochronology and thermochronology to determine the relative importance of tectonic and geomorphic forces that shape the spectacular landscapes of the Colorado Plateau, Arizona and region. In addition to the scientific goals, the meeting participants emphasized the iconic status of Grand Canyon for geosciences and the importance of good communication between the research community, the geoscience education/interpretation community, the public, and the media. Building on a century-long tradition, this region still provides a globally important natural laboratory for studies of the interactions of erosion and tectonism in shaping the landscape of elevated plateaus.
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Beard, L.S., Karlstrom, K.E., Young, R.A., and Billingsley, G.H., eds., 2011, CRevolution 2—Origin and evolution of the Colorado River system, workshop abstracts: U.S. Geological Survey Open-File Report 2011–1210, 300 p., available at https://pubs.usgs.gov/of/2011/1210/.
The Willow Beach Beds—A Pre-Colorado River Axial-Basin Deposit
Origin of the Ancestral Colorado and Gunnison Rivers and Post-10 Ma River Incision Rates in Western Colorado
Kingman Uplift, Paleovalleys and Extensional Foundering in Northwest Arizona
Oligocene-Early Miocene Incision, Strike-Valley Development, and Aggradation, Mogollon Rim, Verde Valley Region, Arizona—A Potential Analogue for pre-Grand Canyon Development
Late Oligocene-early Miocene Deep Erosion on the Southern Colorado Plateau and the Southern Great Plains
Significance of the Grand Mesa Basalt Field in Western Colorado for Defining the Early History of the Upper Colorado River
Geochemistry of Springs, Travertines and Lacustrine Carbonates of the Grand Canyon Region Over the Past 12 Million Years—The Importance of Groundwater on the Evolution of the Colorado River System
Incision History of Grand Canyon from Dated Colorado River Gravels
Differential Incision Rates in the Upper Colorado River System—Implications for Knickpoint Transience
The Paleogene California River—Evidence of Mojave-Uinta Paleodrainage from U-Pb Ages of Detrital Zircons
Bidahochi Paleogeography and Incision of the Grand Canyon
A Preliminary Sediment Budget for the Colorado River
One Grand Canyon but Four Mechanisms—Was It Antecedence, Superimposition, Overflow, or Piracy?
Incision History of the Little Colorado River based on K/AR and AR/AR Dating of Basalts and U-series Dating of Travertine in the Springerville Area
Miocene-Pliocene Basalt Flows on the East and West Flanks of Wilson Ridge, Arizona, Preserve Multiple Stages in the Depositional History of Adjacent Detrital Wash and Black Canyon Basins, and May Help Constrain Timing of Incision by the Colorado River
Powder Rim Gravel—Deposit of a late Miocene, North-flowing River through the Wyoming-Colorado-Utah Borderland
The Colorado River in Glen Canyon during the Pleistocene—Incision Rates, their Uncertainties, and the Possibility of Ancient Impoundments
A Working Model for the Evolution of the Grand Canyon/Colorado Plateau Region—Laramide to Present
Mio-Pliocene Erosional Exhumation of the Central Colorado Plateau, Eastern Utah—New Insights from Apatite (U-Th)/He Thermochronometry
Robust Geologic Evidence for latest Miocene-earliest Pliocene River Integration via Lake-spillover along the lower Colorado River—Review and New Data
Pliocene Aggradational Sequence of the Lower Colorado River in Longitudinal Profile
Boulders Deposited by Pliocene and Pleistocene Floods on the Lower Colorado River
Holocene Aggradation of the Lower Colorado River in Mohave Valley, California and Arizona
Evidence from the Colorado River System for Surface Uplift of the Colorado Rockies and Western Colorado Plateau in the last 10 Ma Driven by Mantle Flow and Buoyancy
A Summary and Evaluation of Thermochronologic Constraints on the Exhumation History of the Colorado Plateau–Rocky Mountain Region
Detrital Zircon Record of Colorado River Integration into the Salton Trough
Unroofing and Incision of the Grand Canyon Region as Constrained through Low-Temperature Thermochronology
Syntectonic Deposition and Paleohydrology of the Spring-Fed Hualapai Limestone and Implications for the 6-5 Ma Integration of the Colorado River System through the Grand Canyon
The Miocene(?) Crooked Ridge River in Northern Arizona and its Implications for the Colorado River and Grand Canyon
The Muddy Creek Formation at the Mouth of the Grand Canyon—Constraint or Chimera?
Observations of the Bouse Formation in Chemehuevi and Parker Valleys, California and Arizona
Quaternary Geology and Geomorphology of the Fremont River drainage Basin, South-central Utah
Geologic Evolution of the Mid-Tertiary Ash Creek Paleovalley, Black Hills, Central Arizona
Dating of Pliocene Colorado River Sediments—Implications for Cosmogenic Burial Dating and Evolution of the Colorado River
Update on Microfossil Studies in the Northern Gulf of California, Salton Trough, and Lower Colorado River
Ancestral Colorado River Exit from the Plateau Province—Salt River Hypothesis
A Tale of Two Monoclines
Cenozoic Evolution of the Grand Canyon and the Colorado Plateau Driven by Mantle Dynamics?
Quaternary History of the Black Canyon of the Gunnison, Colorado
A Brief Review of Sr Isotopic Evidence for the Setting and Evolution of the Miocene-Pliocene Hualapai-Bouse Lake System
Updates on the Tectonics and Paleogeography of the Lake Mead Region from ~25 to ~8 Ma—Lakes and Local Drainages within an Extending Orogen, but no Through-going River?
The California River and its Role in Carving Grand Canyon
Oligocene Tuff Corroborates Older Paleocene-Eocene Age of Hualapai Plateau Basal Tertiary Section
Early Cenozoic “Rim Gravel” of Arizona—Age, Distribution and Geologic Significance
Denudational Flexural Isostacy of the Colorado Plateau: Implications for incision rates and tectonic uplift