Paradox Valley

Paradox Valley trends northwest-southeast and measures about {{convert|3|to|5|mi|km|sigfig=1}} wide and {{convert|25|mi|km}} long. It lies along the extreme western edge of Colorado, close to the border with Utah, about {{convert|50|mi|km}} south of the city of Grand Junction. The La Sal Range rises just to the northwest in Utah. State Highway 90 follows Paradox Valley on its way from Naturita to the Utah state line, crossing the Dolores River Bridge near the small unincorporated town of Bedrock. The town of Paradox lies a few miles north of the highway. Elevations on the valley floor range from about {{convert|5000|ft|m}} at the Dolores River to nearly {{convert|6000|ft|m}} at the southeast end. Steep parallel sandstone and shale walls bound the valley to the northeast and southwest.

The valley was named in 1875 by geologist and surveyor Albert Charles Peale{{cite gnis|185690|Paradox Valley|entrydate=October 13, 1978|accessdate=November 28, 2009}} after he noted that the Dolores River had a "desire to perform strange and unexpected things" in the area.{{cite book|url=https://books.google.com/books?id=4rrZAAAAMAAJ&pg=PA343|title=Ninth Annual Report of the Geological and Geographical Survey of the Territories|publisher=United States Department of the Interior|year=1877|editor=Hayden, F.V.|editor-link=Ferdinand Vandeveer Hayden|pages=343|accessdate=November 30, 2009}} Instead of flowing down the valley's thalweg, the river emerges from a narrow gap in one wall, cuts perpendicularly across the mostly level valley floor, and exits through another gap in the opposite wall. As a consequence of this unusual geography, the valley cannot be easily irrigated by the Dolores River, but springs and streams fed by snowmelt from the La Sal Range support farming in the northwestern third of the valley.{{cite web|url=http://www.cdphe.state.co.us/hm/rad/rml/energyfuels/application/envrpt/sec1.pdf|title=Energy Fuels Inc. Pinon Ridge Uranium Mill Application|publisher=Energy Fuels Incorporated|accessdate=December 2, 2009}}

Near the center of the valley, the town of Bedrock experiences average highs ranging from {{convert|45|F|C}} in December to {{convert|96|F|C}} in July. Average lows range from {{convert|13|F|C}} in December to {{convert|54|F|C}} in July. An average of {{convert|11|in|cm}} of precipitation, including {{convert|9|in|cm}} of snow, fall annually at Bedrock.{{cite web|url=http://www.wrcc.dri.edu/cgi-bin/cliMAIN.pl?co0581|title=BEDROCK 1 N, COLORADO (050581) Period of Record Monthly Climate Summary|publisher=Western Regional Climate Center|accessdate=December 2, 2009}}

File:Paradox Valley NASA.jpg Dolores River (lower right to upper left) is seen crossing Paradox Valley (center) in this simulated view]]

File:ParadoxBasin (2).jpg

File:ParadoxBasin.jpg

The apparent paradox of Paradox Valley can be explained by salt tectonics. The valley is a collapsed anticline, a type of geological fold. About 300 million years ago, during the middle Pennsylvanian period, when the Dolores River was already in existence, high pressures on lands to the northeast caused underlying salt deposits to flow towards where the valley is today. The salt encountered a buried fault-block ridge and was deflected upwards, penetrating the overlying rock strata and forming a salt dome. The salt may not have actually been exposed on the surface, but groundwater entering the top of the dome dissolved the underlying salt beds, allowing the center to collapse, forming what is today Paradox Valley. This process took place over about 150 million years, a long enough time for the Dolores River to downcut into the land and maintain its ancient course. The same process also created the Moab Valley (Spanish Valley) to the west, itself cut crosswise in a similar fashion by the Colorado River.{{cite book|url=https://books.google.com/books?id=CHut1M-yAb0C&pg=PA63|title=The Colorado Plateau: a geologic history|last=Baars|first=Donald L.|publisher=University of New Mexico Press|year=2000|isbn=978-0-8263-2301-9|pages=63–67|accessdate=November 30, 2009}}

The Paradox Formation, a geological formation containing salt, gypsum, anhydrite, shale, sandstone, and limestone,{{cite web|url=http://ngmdb.usgs.gov/Geolex/NewRefsmry/sumry_9763.html|title=Summary of Citation - Geologic Unit: Paradox|work=GEOLEX Database|publisher=United States Geological Survey|accessdate=November 28, 2009}} is named after exposures found in Paradox Valley. The Paradox Basin, a geologic province throughout which the Paradox Formation is found, also bears the name of the valley.

Paradox Valley was within the historical domain of the Ute tribe. An 1868 treaty created a reservation for the Utes over much of western Colorado, including Paradox Valley.{{cite web|url=http://www.southern-ute.nsn.us/history/index.html|title=Southern Ute Tribal History|publisher=Southern Ute Indian Tribe|archiveurl=https://web.archive.org/web/20091207010647/http://www.southern-ute.nsn.us/history/index.html|archivedate=December 7, 2009|url-status=dead|accessdate=November 30, 2009}} Squatters began grazing cattle in the valley as early as 1877, in violation of the treaty.{{cite book|url=http://www.nps.gov/history/history/online_books/blm/co/10/chap7.htm|title=Frontier in Transition: A History of Southwestern Colorado|last=O'Rourke|first=Paul M.|publisher=Colorado State Office, Bureau of Land Management|year=1980|accessdate=November 30, 2009}} By 1881, the Utes had been forced out of the area, and in 1882 the United States Congress officially opened the land to settlement. Springs and streams allowed farming in the northwest end of the valley, and the mid-1890s discovery of copper at the future site of the Cashin Mine near the town of Bedrock brought in a further influx of settlers.{{cite news|url=http://www.montrosepress.com/articles/2008/05/19/news/doc483111846441d288246887.txt|title=Paradox: Stories of the Wild West|last=Cox|first=Marilyn|date=May 19, 2008|work=Montrose Daily Press|accessdate=December 1, 2009}} The valley and the surrounding plateau soon also became an important source of radioactive materials, including radium and uranium. In 1913, The New York Times identified carnotite mines near Paradox Valley as the source of "the greatest radium ore deposits in the world".{{cite news|url=https://timesmachine.nytimes.com/timesmachine/1913/12/27/100293509.pdf|title=$100,000 Radium Test to Save Bremmer's Life|date=December 27, 1913|work=New York Times|accessdate=December 3, 2009}} Production of radium ceased in 1922 when richer deposits were found in the Belgian Congo, but production of uranium and vanadium continued throughout most of the century.

File:Paradox Valley Unit Map.pngs]]

Near-surface salt beds up to {{convert|14000|ft|m}} thick still underlie Paradox Valley. The Dolores River, a tributary of the Colorado River, naturally picks up about 100,000-200,000 tons of salt annually on its way through the valley. In the 1980s, the United States Bureau of Reclamation began construction of a pumping facility known as the Paradox Valley Unit. The PVU, a part of the wider Colorado River Basin Salinity Control Project, became fully operational in 1996 and collects saline groundwater from 12 shallow wells along the Dolores River. The system then dilutes the brine with water and a corrosion inhibitor and transports it to a high-pressure injection well, where it is deposited {{convert|14000|to|16000|ft|m}} deep into Precambrian and Paleozoic rocks. A 2001 study found that the total salt reaching the Dolores had declined by about 90%, although this may have been the result of a period of low precipitation during the measurement period.{{cite web|url=http://pubs.usgs.gov/wri/wri02-4275/pdf/wrir02-4275.pdf|title=The Effect of the Paradox Valley Unit on the Dissolved-Solids Load of the Dolores River near Bedrock, Colorado, 1988–2001|last=Chafin|first=Daniel T.|date=January 2003|publisher=United States Geological Survey|accessdate=November 28, 2009}} As of 2009, the PVU removes about 113,000 tons of salt annually from Paradox Valley.{{cite web|url=http://www.usbr.gov/projects/Project.jsp?proj_Name=CRBSCP+-+Paradox+Valley+Unit+-+Title+II|title=Project details - CRBSCP - Paradox Valley Unit - Title II|date=June 3, 2009|publisher=Bureau of Reclamation|accessdate=November 28, 2009|archive-url=https://web.archive.org/web/20100926034344/http://www.usbr.gov/projects/Project.jsp?proj_Name=CRBSCP+-+Paradox+Valley+Unit+-+Title+II|archive-date=September 26, 2010|url-status=dead}}

The injection well of the Paradox Valley Unit has induced thousands of earthquakes, including at least 4,000 prior to the year 2001.{{cite journal|last1=Ake|first1=Jon|last2=Mahrer|first2=Kenneth|last3=O’Connell|first3=Daniel|last4=Block|first4=Lisa|date=April 2005|title=Deep-Injection and Closely Monitored Induced Seismicity at Paradox Valley, Colorado|url=https://zenodo.org/record/1235782/files/article.pdf|journal=Bulletin of the Seismological Society of America|publisher=Seismological Society of America|volume=95|issue=2|pages=664–683|doi=10.1785/0120040072|accessdate=November 30, 2009}} Most were below the threshold of human detection, but at least 15 have been over 2.5 in magnitude, the largest being a 4.3 magnitude quake on May 27, 2000. The PVU suspended operations for 28 days following this quake, but later resumed injections at a lower rate.{{cite news|url=http://www.rmag.org/rmag_uploads/outcrops/0302.pdf|title=What's Shaking in Bedrock? The Paradox Valley Deep-Well Injection Program|last1=Ake|first1=Jon|date=March 2002|work=Outcrop|accessdate=November 30, 2009|archiveurl=https://web.archive.org/web/20101128112135/http://rmag.org/rmag_uploads/outcrops/0302.pdf|archivedate=November 28, 2010|url-status=bot: unknown|publisher=Rocky Mountain Association of Geologists|last2=Mahrer|first2=Kenneth|last3=O’Connell|first3=Daniel|last4=Block|first4=Lisa}} Further earthquakes have been linked with the operation, including a 3.9 magnitude quake in 2004.{{cite news|url=http://findarticles.com/p/articles/mi_qn4188/is_20041115/ai_n11482702/|title=Magnitude 3.9 earthquake is linked to brine pumping|date=November 15, 2004|accessdate=December 2, 2009|publisher=Associated Press}}

{{see also|Uranium mining in Colorado}}

In 2009 Energy Fuels Resources Corporation, a subsidiary of Toronto-based Energy Fuels Incorporated, proposed the construction of a uranium mill in the southeast end of Paradox Valley.{{cite news|url=http://www.telluridewatch.com/pages/full_story/push?article-State+Receives+Uranium+Mill+Application%20&id=4777411-State+Receives+Uranium+Mill+Application&instance=news_special_coverage_right_column|title=State Receives Uranium Mill Application|date=November 24, 2009|work=Telluride Watch|accessdate=November 28, 2009|archive-url=https://web.archive.org/web/20160130013946/http://www.telluridewatch.com/pages/full_story/push?article-State+Receives+Uranium+Mill+Application%20&id=4777411-State+Receives+Uranium+Mill+Application&instance=news_special_coverage_right_column|archive-date=January 30, 2016|url-status=dead}} Called the Piñon Ridge Mill, it would have been capable of processing 500 tons of uranium ore per day. Legal action tied up the project for many years,Wright, S.T. [https://www.telluridenews.com/news/article_740b88b0-83fb-11e9-a989-3f550b6d148e.html Judge greenlights renewed uranium mining in West End.] Telluride Daily Planet Jun 2, 2019. and as of September 2020 the project appears to have died.Blevins, J. [https://coloradosun.com/2020/09/15/naturita-campv-tourism-recreation-replacing-mining/ A former mining camp is converting into a boutique getaway, sparking hope in Montrose County’s West End.] The Colorado Sun, Sep 15, 2020.

• Paradox basin
• Paradox, Colorado

{{Reflist|30em}}

• [http://waterdata.usgs.gov/nwis/dv/?site_no=09169500&agency_cd=USGS&referred_module=qw Upstream] and [http://waterdata.usgs.gov/nwis/dv/?site_no=09171100&agency_cd=USGS&referred_module=qw downstream] water quality data from the United States Geological Survey
• [https://web.archive.org/web/20161013135927/http://www.panoramio.com/photo/22753516 Photo of Paradox Valley near Bedrock, CO on Panoramio]

{{Montrose County, Colorado}}

Category:Landforms of Montrose County, Colorado

Category:Valleys of Colorado

Category:Geology of Colorado