Skip to main content

Boulder








Boulder


From Wikipedia, the free encyclopedia

Jump to navigation
Jump to search





This balancing boulder, "Balanced Rock" stands in Garden of the Gods park in Colorado Springs, Colorado, United States.





Devonian conglomerate in Scotland with clasts up to boulder in size


In geology, a boulder is a rock fragment with size greater than 25.6 centimetres (10.1 in) in diameter.[1] Smaller pieces are called cobbles and pebbles. While a boulder may be small enough to move or roll manually, others are extremely massive.[2]
In common usage, a boulder is too large for a person to move. Smaller boulders are usually just called rocks or stones. The word boulder is short for boulder stone, from Middle English bulderston or Swedish bullersten.[3]


In places covered by ice sheets during Ice Ages, such as Scandinavia, northern North America, and Siberia, glacial erratics are common. Erratics are boulders picked up by ice sheets during their advance, and deposited when they melt.[2] They are called "erratic" because they typically are of a different rock type than the bedrock on which they are deposited. One of them is used as the pedestal of the Bronze Horseman in Saint Petersburg, Russia.


Some noted rock formations involve giant boulders exposed by erosion, such as the Devil's Marbles in Australia's Northern Territory, the Horeke basalts in New Zealand, where an entire valley contains only boulders, and The Baths on the island of Virgin Gorda in the British Virgin Islands.


Boulder-sized clasts are found in some sedimentary rocks, such as coarse conglomerate and boulder clay.


The climbing of large boulders is called bouldering.



See also[edit]


  • Road debris

  • Monolith


References[edit]



  1. ^ Neuendorf, K.K.E.; Mehl, Jr., J.P.; Jackson, J.A. (editors) (2005). Glossary of Geology (5th edition). Alexandria, Virginia: American Geological Institute. p. 79. ISBN 978-0922152896.CS1 maint: Extra text: authors list (link) .mw-parser-output cite.citationfont-style:inherit.mw-parser-output qquotes:"""""""'""'".mw-parser-output code.cs1-codecolor:inherit;background:inherit;border:inherit;padding:inherit.mw-parser-output .cs1-lock-free abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center.mw-parser-output .cs1-lock-subscription abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registrationcolor:#555.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration spanborder-bottom:1px dotted;cursor:help.mw-parser-output .cs1-hidden-errordisplay:none;font-size:100%.mw-parser-output .cs1-visible-errorfont-size:100%.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-formatfont-size:95%.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-leftpadding-left:0.2em.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-rightpadding-right:0.2em


  2. ^ ab "Boulder". Dictionary.com. Retrieved 24 August 2013.


  3. ^ boulder. (n.d.) Online Etymology Dictionary. Retrieved December 9, 2011, from Dictionary.com website.



External links[edit]


Media related to Boulders at Wikimedia Commons








Retrieved from "https://en.wikipedia.org/w/index.php?title=Boulder&oldid=869822729"





Navigation menu


























(window.RLQ=window.RLQ||).push(function()mw.config.set("wgPageParseReport":"limitreport":"cputime":"0.168","walltime":"0.239","ppvisitednodes":"value":249,"limit":1000000,"ppgeneratednodes":"value":0,"limit":1500000,"postexpandincludesize":"value":4265,"limit":2097152,"templateargumentsize":"value":107,"limit":2097152,"expansiondepth":"value":8,"limit":40,"expensivefunctioncount":"value":0,"limit":500,"unstrip-depth":"value":1,"limit":20,"unstrip-size":"value":5927,"limit":5000000,"entityaccesscount":"value":1,"limit":400,"timingprofile":["100.00% 213.306 1 -total"," 33.45% 71.351 1 Template:Commonscat-inline"," 27.89% 59.488 1 Template:Cite_book"," 17.42% 37.149 1 Template:About"," 13.79% 29.423 1 Template:Convert"," 3.23% 6.894 1 Template:Cite_web"," 2.55% 5.449 1 Template:Sister-inline"],"scribunto":"limitreport-timeusage":"value":"0.106","limit":"10.000","limitreport-memusage":"value":4491646,"limit":52428800,"cachereport":"origin":"mw1243","timestamp":"20181212155949","ttl":1900800,"transientcontent":false););"@context":"https://schema.org","@type":"Article","name":"Boulder","url":"https://en.wikipedia.org/wiki/Boulder","sameAs":"http://www.wikidata.org/entity/Q581776","mainEntity":"http://www.wikidata.org/entity/Q581776","author":"@type":"Organization","name":"Contributors to Wikimedia projects","publisher":"@type":"Organization","name":"Wikimedia Foundation, Inc.","logo":"@type":"ImageObject","url":"https://www.wikimedia.org/static/images/wmf-hor-googpub.png","datePublished":"2002-07-06T17:45:36Z","dateModified":"2018-11-20T16:24:18Z","image":"https://upload.wikimedia.org/wikipedia/commons/2/2f/Balanced_Rock.jpg","headline":"natural rock fragment (larger than 200 mm in diameter according to ISO 14688)"(window.RLQ=window.RLQ||).push(function()mw.config.set("wgBackendResponseTime":115,"wgHostname":"mw1256"););

Popular posts from this blog

Top Tejano songwriter Luis Silva dead of heart attack at 64

政党

天津地下鉄3号線