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Research about Arizona;Colorado;New Mexico;Utah

Source-linked reports with geographic coverage including Arizona;Colorado;New Mexico;Utah.

14 recordsLinked to original sources
USGS2012

Introduction: CRevolution 2: origin and evolution of the Colorado River System II

A 2010 Colorado River symposium held in Flagstaff, Arizona, in May 2010, had 70 participants who engaged in intense debate about the origin and evolution of the Colorado River system. This symposium, built on two previous decadal scientific meetings, focused on forging scientific consensus where possible, while also 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, with consensus that multidisciplinary studies involving differential incision studies and additional geochronology and thermochronology are needed to test the relative importance of tectonic and geomorphic forcings in shaping the spectacular landscapes of the Colorado Plateau 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 the shaping landscape of elevated plateaus.

Arizona;Colorado;New Mexico;Utah↗
USGS2012

WaterSMART-The Colorado River Basin focus-area study

Increasing demand for the limited water resources of the United States continues to put pressure on water-resource agencies to balance the competing needs of ecosystem health with municipal, agricultural, and recreational uses. In 2007, the U.S. Geological Survey (USGS) identified a National Water Census as one of six pivotal future science directions for the USGS in the following decade. The envisioned USGS National Water Census would evaluate large-scale effects of changes in land use and land cover, water use, and climate on water availability, water quality, and human and aquatic ecosystem health. The passage of the SECURE (Science and Engineering to Comprehensively Understand and Responsibly Enhance) Water Act in 2009 was a key step towards implementing the USGS National Water Census. Section 9508 of the Act authorizes a "national water availability and use assessment program" within the USGS (1) to provide a more accurate assessment of the status of the water resources of the United States; and (2) to develop the science for improved forecasts of the availability of water for future economic, energy production, and environmental uses. Initial funding for the USGS to begin working on the National Water Census came with the approval of the U.S. Department of the Interior's WaterSMART (Sustain and Manage America's Resources for Tomorrow) Initiative. The WaterSMART Initiative provides funding to the USGS, Bureau of Reclamation, and U.S. Department of Energy to achieve a sustainable water strategy to meet the Nation's water needs. WaterSMART funding also allowed the USGS to begin the national Water Availability and Use Assessment, as called for under the SECURE Water Act.

Arizona;Colorado;New Mexico;Utah↗
USGS2012

Colorado Plateaus Ecoregion: Chapter 21 in Status and trends of land change in the Western United States--1973 to 2000

The Colorado Plateaus Ecoregion covers approximately 129,617 km 2 (50,045 mi 2 ) within southern and eastern Utah, western Colorado, and the extreme northern part of Arizona (fig. 1). The terrain of this ecoregion is characterized by broad plateaus, ancient volcanoes, and deeply dissected canyons (Booth and others, 1999; fig. 2). The ecoregion is bounded on the east by the Wyoming Basin and Southern Rockies Ecoregions in Colorado and on the northwest by the Wasatch and Uinta Mountains Ecoregion in northern and central Utah. To the south, the ecoregion borders the Arizona/New Mexico Plateau Ecoregion, which has a higher elevation and more grasslands than the Colorado Plateaus Ecoregion (Omernik, 1987; U.S. Environmental Protection Agency, 1997).

Arizona;Colorado;New Mexico;Utah↗
USGS1958

Directional resistivity measurements in exploration for uranium deposits on the Colorado Plateau

A study of the electrical properties of the Morrison formation in the Uravan mineral belt of the Colorado Plateaus province indicated that there is a significant correlation between electrical resistivity and the relative favorability for occurrence of ore. The differences in resistivity were not large enough to provide a recognizable target for standard resistivity' field methods, especially where the ore-bearing sandstone member is more than a few hundred feet deep. Measurement of resistivity trends by placing one electrode in a drill hole and spreading the others out radially on the surface seemed to offer a means of exploiting the resistivity-favorability correlation. Field tests of such directional resistivity measurements were made in the Spud Patch area in San Miguel County, Colo., and the White Canyon district) San Juan County, Utah. In the Spud Patch area two methods were tried; in one a current electrode was placed in the drill. hole, and in the other, a potential electrode. The second was the more tedious but provided the more readily interpretable results. A comparison of the resistivity trends thus determined with the favorability estimated from geologic indexes indicated that directional resistivity methods could predict the location of favorable areas at distances of 600 to 1,000 feet with a high degree of success. In the White Canyon district directional resistivity measurements were made on the assumption that the conglomerate which is found in many channels filled with the Shinarump member of the Chinle formation has a high resistivity. The measurements were successful in tracing the channel conglomerate where surface conditions were favorable.

Arizona;Colorado;New Mexico;Utah↗
USGS1956

Sources of the elements in the sandstone-type uranium deposits of the Colorado Plateau

Sandstone-type uranium deposits of the Colorado Plateau are epigenetic. Certain elements have been added locally to the sandstone host to form the deposits; the added fraction of each element in the deposits is call extrinsic to distinguish it from the part present in the original unmineralized host. The principal extrinsic components, in their approximate order of abundance, are vanadium, iron magnesium, uranium, sulfur, arsenic, copper, lead, molbedenum, selenium, cobalt, and nickel. At lest six possible sources of the extrinsic components of the uranium deposits may be considered reasonably likely: 1) the sandstone beds enclosing the uranium deposits, 2) the marine Mancos shales of Cretaceous ages, 3) bentonitic shales of Jurassic and Triassic age, 4) petroliferous rocks of Pennsylvanian age, 5) Precambrian crystalline rocks underlying the Colorado Plateau, and 6) magmatic reservoirs of latest Cretaceous or Tertiary age. If the major source of some of the elements of external to the sandstone beds enclosing the deposits, it is likely that several sources have contributed to some if not most of the extrinsic components and that the importance of the various sources differs from one component to the next. Precambrian crystalline rocks are considered the most likely major source of the extrinsic uranium in the deposits.

Arizona;Colorado;New Mexico;Utah↗