{{short description|Tall, thin spire of relatively soft rock usually topped by harder rock}} {{redirect|Tent Rocks|Tent Rocks National Monument|Kasha-Katuwe Tent Rocks National Monument}} {{other uses|Hoodoo (disambiguation){{!}}Hoodoo}} [[File:USA 10654 Bryce Canyon Luca Galuzzi 2007.jpg|thumb|300px|Hoodoos in Bryce Canyon National Park, Utah]]
A '''hoodoo''' (also called a '''tent rock''', '''fairy chimney''', or '''earth pyramid''') is a tall, thin spire of rock formed by erosion. Hoodoos typically consist of relatively soft rock topped by harder, less easily eroded stone that protects each column from the elements. They generally form within sedimentary rock and volcanic rock formations.
Hoodoos range in size from the height of an average human to heights exceeding a 10-story building. Hoodoo shapes are affected by the erosional patterns of alternating hard and softer rock layers. Minerals deposited within different rock types can cause hoodoos to have different colors throughout their height.
==Etymology== In certain regions of western North America these rocky structures are called hoodoos, a name that comes from a Southern Paiute word, ''oo’doo'', which implies something that inspires fear.<ref>{{Cite web |last=Chen |first=Eve |title='You need a word at least as strong as magic' to describe Bryce Canyon National Park |url=https://www.usatoday.com/story/travel/experience/national-parks/2023/06/03/bryce-canyon-national-park-tips-utah/70280986007/ |access-date=2024-12-01 |website=USA TODAY |language=en-US}}</ref><ref name="NPSHoodoo">{{cite web | url=https://www.nps.gov/places/000/bryce-point.htm | title=Bryce Point | publisher=National Park Service | date=2024-10-10 | access-date=2024-12-02}}</ref> Hoodoos are featured in some traditional legends of Indigenous peoples of the North American Southwest. For example, hoodoos in Bryce Canyon National Park were considered petrified remains of ancient beings who had been sanctioned for misbehavior.<ref>{{cite web |title=American Indian History |url=https://www.nps.gov/brca/learn/historyculture/americanindianhistory.htm |website=Brice Canyon National Park, Utah |publisher=National Park Service |access-date=1 June 2022 |date=23 June 2020}}</ref> Despite the matching spelling, the term for these rock formations is not related to Hoodoo spirituality.
==Occurrence== [[File:SierradeOrganos.jpg|thumb|Hoodoos in Sierra de Órganos National Park, Mexico]] Hoodoos are found mainly in the desert in dry, hot areas. While visually similar to pinnacles (or spires), hoodoos are unique in their variable thickness, often described as having a totem pole-shaped body. A spire, conversely, has a smoother profile or uniform thickness that tapers from the ground upward.
thumb|Goblin Valley State Park, Utah Hoodoo formations are commonly found on the Colorado Plateau and in the Badland regions of the northern Great Plains of North America. While hoodoos are scattered throughout these areas, nowhere in the world are they so abundant as in the northern section of Bryce Canyon National Park in Utah.<ref>{{Cite web|url=https://www.nps.gov/brca/learn/nature/geologicformations.htm|title=Geologic Formations – Bryce Canyon National Park (U.S. National Park Service)|website=www.nps.gov|language=en|access-date=2019-08-21}}</ref> Hoodoos are also very prominent a few hundred miles away at Goblin Valley State Park on the eastern side of the San Rafael Swell, at Kasha-Katuwe Tent Rocks National Monument in north central New Mexico, and in the Chiricahua National Monument of Southeast Arizona.<ref>{{Cite web|url=https://www.nps.gov/chir/index.htm|title=Chiricahua National Monument (U.S. National Park Service)|website=www.nps.gov|language=en|access-date=2019-08-13}}</ref> Some hoodoos are found in Sombrerete, Mexico at the Sierra de Organos National Park.[[File:Tent rocks between Cavusin and Avanos.jpg|thumb|Tent rocks (''peribacası'') near Çavuşin, Cappadocia, Turkey]]
Hoodoos are also found in the Cappadocia region of Turkey, where houses have been carved into the formations. These hoodoos were depicted on the reverse of the Turkish 50 new lira banknote of 2005–2009.<ref name="MyUser_Tcmb.gov.tr_March_30_2015c">{{cite web |url=http://www.tcmb.gov.tr/wps/wcm/connect/TCMB+EN/TCMB+EN/Main+Menu/BANKNOTES/Banknotes+of+the+Republic+of+Turkey/Emission+Group/8-Emission-Group/Emission17 |title=E8 – Fifty New Turkish Lira |website=Tcmb.gov.tr |author=Central Bank of the Republic of Turkey |access-date= March 30, 2015}}</ref>
[[File:2014 Prowincja Sjunik, Goris, Widok na Stary Goris (Kores) (04).jpg|thumb|Hoodoos in Hin Khndzoresk, Armenia]]
In Armenia, hoodoos are found in Goris, Khndzoresk, Hin Khot and several other places in Syunik Province, where many were once carved into and inhabited or used.
[[File:DemoisellesCoifféesPontis.jpg|thumb|Demoiselles Coiffées de Pontis, southern France]] In French, the formations are called ''demoiselles coiffées'' (ladies with hairdos) or ''cheminées de fées'' (fairy chimneys) and several are found in the Alpes-de-Haute-Provence; one of the best-known examples is the formation called Demoiselles Coiffées de Pontis.<ref>{{cite book|last=Haug|first=Émile|title=Traité de géologie|url=https://books.google.com/books?id=02sNAAAAYAAJ&pg=PA384-IA13|volume=1|year=1907|publisher=Librairie Armand Colin|page=386}}</ref><ref>{{cite book|last=Godefroy|first=René|title=La nature alpine: exposé de géographie physique|url=https://books.google.com/books?id=1ZDtAAAAMAAJ&q=Demoiselles+Coiff%C3%A9es+Pontis|year=1940|publisher=B. Arthaud|page=121}}</ref>
The hoodoo stones of Yehliu on the northern coast of Taiwan are unusual for their coastal setting. The stones formed as the seabed rose rapidly out of the ocean during the Miocene epoch.<ref>{{cite journal|last1=Hong|first1=Eason|last2=Huang|first2=Eugene|title=Formation of the pedestal rocks in the Taliao Formation, northern coast of Taiwan|journal=Western Pacific Earth Sciences|date=February 2001|volume=1|issue=1|pages=99–106|url=http://www.earth.sinica.edu.tw/papers/V1n1p099.pdf|access-date=March 31, 2015|archive-url=https://web.archive.org/web/20170205214147/http://www.earth.sinica.edu.tw/papers/V1n1p099.pdf|archive-date=February 5, 2017|url-status=dead}}</ref> Efforts have been made to slow the erosion in the case of iconic specimens in Wanli.
The Awa Sand Pillars found in Tokushima Prefecture, Japan, are hoodoos made from layers of compacted gravel and sandstone.<ref>{{Cite news|url=https://setouchifinder.com/en/detail/429|title=The "Earth Pillars of Awa"! A Mysterious Phenomena Found in Only 3 Places Worldwide!|work=Stouchi Finder|access-date=2018-11-02|language=en|archive-date=2018-11-13|archive-url=https://web.archive.org/web/20181113214221/https://setouchifinder.com/en/detail/429|url-status=dead}}</ref>
Đavolja Varoš (Devil's Town) hoodoos in Serbia feature about 200 formations described as earth pyramids or towers by local inhabitants. Since 1959, Đavolja Varoš has been protected by the state. The site was also a nominee in the New Seven Wonders of Nature campaign.<ref>{{cite web|title=Djavolja Varos, Rock Formation|url=http://www.new7wonders.com/nature/en/nominees/europe/c/DavoljaVarosRockFormation/|website=New 7 Wonders|access-date=March 31, 2015|archive-url=https://web.archive.org/web/20090709204835/http://www.new7wonders.com/nature/en/nominees/europe/c/DavoljaVarosRockFormation/|archive-date=July 9, 2009}}</ref>
thumb|Hoodoos in Drumheller, Alberta The hoodoos found in Drumheller, Alberta, are composed of clay and sand deposited between 70 and 75 million years ago during the Cretaceous Period. These hoodoos can maintain a unique mushroom-like appearance as the underlying base erodes at a faster rate compared to the capstones at a rate of nearly one centimeter per year, faster than most geologic structures.<ref>{{cite web |url=http://www.tyrrellmuseum.com/exhibits/1674.htm |title=Hoodoos |newspaper=Tyrrellmuseum.com |author=Royal Tyrrell Museum |access-date=March 30, 2015|url-status=dead|archive-url=https://web.archive.org/web/20200127190734/https://tyrrellmuseum.com/exhibits/1674.htm|archive-date=27 January 2020}}</ref>
==Formation== [[File:Đavolja Varoš.jpg|thumb|Đavolja Varoš (Devil's Town), Serbia – a volcanic rock formation with andesite caps]]
Hoodoos typically form in areas where a thick layer of a relatively soft rock, such as mudstone, poorly cemented sandstone, or tuff (consolidated volcanic ash), is covered by a thin layer of hard rock, such as well-cemented sandstone, limestone, or basalt. In glaciated mountainous valleys, the soft eroded material may be glacial till with the protective capstones being large boulders in the till. Over time, cracks in the resistant layer allow the much softer rock beneath to be eroded and washed away. Hoodoos form where a small cap of the resistant layer remains, and protects a cone of the underlying softer layer from erosion. The heavy cap pressing downward gives the pedestal of the hoodoo its strength to resist erosion.<ref>{{Cite journal|last1=Bruthans|first1=Jiri|last2=Soukup|first2=Jan|last3=Vaculikova|first3=Jana|last4=Filippi|first4=Michal|last5=Schweigstillova|first5=Jana|last6=Mayo|first6=Alan L.|last7=Masin|first7=David|last8=Kletetschka|first8=Gunther|last9=Rihosek|first9=Jaroslav|date=July 2014|title=Sandstone landforms shaped by negative feedback between stress and erosion|journal=Nature Geoscience|language=En|volume=7|issue=8|pages=597–601|doi=10.1038/ngeo2209|issn=1752-0908|bibcode=2014NatGe...7..597B}}</ref> With time, erosion of the soft layer causes the cap to be undercut, eventually falling off, and the remaining cone is then quickly eroded.<ref name="Yilmaz">{{cite journal |last1=Yilmaz |first1=H.M. |last2=Yakar |first2=M. |last3=Mutluoglu |first3=O. |last4=Kavurmaci |first4=M.M. |last5=Yurt |first5=K. |s2cid=140180182 |year=2012 |title=Monitoring of soil erosion in Cappadocia region (Selime-Aksaray-Turkey) |journal=Environmental Earth Sciences |publisher=Springer |volume=66 |issue=1 |pages=75–81 |doi=10.1007/s12665-011-1208-4 |bibcode=2012EES....66...75Y }}</ref><ref name="Hopkins">{{cite book|last=Hopkins|first=R.L.|title=Hiking the Southwest's Geology: Four Corners Region|publisher=The Mountaineers Books|year=2003|pages=107–108|chapter=Coal Mine Canyon|isbn=9780898868562|chapter-url=https://books.google.com/books?id=d_mqypQ0YgAC&q=hoodoos+formation+resistant+cap&pg=PA187}}</ref>
Typically, hoodoos form from weathering processes that continuously work together in eroding the edges of a rock formation known as a fin. For example, the primary weathering force at Bryce Canyon is frost wedging. The hoodoos at Bryce Canyon experience more than 200 freeze-thaw cycles each year. In winter, melting snow in the form of water seeps into cracks and then freezes at night. When water freezes, it expands by almost ten percent, prying open cracks and gradually widening them, similarly to the way a pothole forms in a paved road.
Rain is another weathering process causing this erosion. In most places today, rainwater is slightly acidic, which lets the weak carbonic acid slowly dissolve limestone grain by grain. It is this process that rounds the edges of hoodoos and gives them their lumpy and bulging profiles. Where internal mudstone and siltstone layers interrupt the limestone, the rock is more resistant to the chemical weathering because of the comparative lack of limestone. Many of the more durable hoodoos are capped with a special kind of magnesium-rich limestone called dolomite. Dolomite, being fortified by the mineral magnesium, dissolves at a much slower rate, and consequently protects the weaker limestone underneath it. Rain is also the chief source of erosion that washes away debris. For example, monsoon-type rainstorms travel through the Bryce Canyon region in summer, bringing short-duration high-intensity rain.<ref>{{cite web|url=https://home.nps.gov/brca/learn/nature/hoodoos.htm|title=Hoodoos|work=nps.gov|access-date=22 March 2015}}</ref> {{wide image|Hoodoo formation-Big.jpg|600px|Progressive erosion producing plateau, fin, window (or arch), and hoodoos}} thumb|Les Orgues d'Ille-sur-Têt, Southern France
==See also== {{columns-list|colwidth=30em| * {{annotated link|Balancing rock}} * {{annotated link|Bisti/De-Na-Zin Wilderness}} * {{annotated link|Butte}} * {{annotated link|Chiricahua National Monument}} * {{annotated link|City of Rocks State Park}} * {{annotated link|Earth pyramids of South Tyrol}}, Italy * {{annotated link|Geology of the Bryce Canyon area}} * {{annotated link|Göreme Historical National Park}}, Cappadocia, Turkey * {{annotated link|Kasha-Katuwe Tent Rocks National Monument}}, New Mexico * {{annotated link|List of rock formations}} * {{annotated link|Mushroom rock}} * {{annotated link|Princess of Hope}} * {{annotated link|Tsingy de Bemaraha Strict Nature Reserve}} * {{annotated link|Tulin (geology)}} * {{annotated link|Yardang}} }}
==References== {{Reflist}}
==Further reading== * DeCourten, Frank. 1994. ''Shadows of Time, the Geology of Bryce Canyon National Park''. Bryce Canyon Natural History Association. * Kiver, Eugene P., Harris, David V. 1999. ''Geology of U.S. Parklands 5th ed''. John Wiley & Sons, Inc. 522–528. * Sprinkel, Douglas A., Chidsey, Thomas C. Jr., Anderson, Paul B. 2000. ''Geology of Utah's Parks and Monuments''. Publishers Press: 37–59
==External links== {{Commons category|Hoodoos}} * [https://home.nps.gov/brca/learn/nature/hoodoos.htm National Park Service: Bryce Canyon National Park: Nature and Geology – Hoodoos] (adapted public domain text) * [http://www.erdpyramiden.com Hoodoos (Erdpyramiden – demoiselles coiffées) world-wide]
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{{DEFAULTSORT:Hoodoo (Geology)}} Category:Rock formations Category:Erosion landforms Category:Bryce Canyon Category:Cappadocia