蛇形丘又稱蛇丘，是一种狭长弯曲的垄岗地形，因蜿蜒如蛇形，故名。蛇形丘一般两坡对称，丘脊狭窄，长度从几十米到上百公里不等，高度一般为10-30米，有时可达70米以上，其延伸方向与冰川运动方向大致相同。主要分布在大陆冰川地区。
形成
蛇形丘的成因主要有两种：
#在冰川开始消融时，冰融水会沿着冰裂隙流入冰川底部，形成冰下隧道，在隧道中流动的冰融水携带大量的砂砾，沿途搬运过程中不断堆积，等到冰川全部融化后，这种隧道堆积物就形成了蛇形丘。
#在夏季气温升高时，冰川消融产生的冰融水在冰川的末端流入冰水湖，其携带的物质则堆积形成冰水三角洲，随着冰川的节节后退，形成了一个个的冰水三角洲，它们连起来就成了串珠状的蛇形丘。
参考
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*[http://www.es.ntnu.edu.tw/home/1_department/g/oceangrophy/Sea92/2/new_page_4-3-1-6.htm 冰河的堆積作用]
外部链接
*[http://www.maine.gov/doc/nrimc/mgs/explore/surficial/facts/surf-10.htm Oblique aerial photo of an esker in Waterford, Maine]
Larry Gedney, "[https://web.archive.org/web/20080223102527/http://www.gi.alaska.edu/ScienceForum/ASF6/674.html Eskers: The Upside-Down Riverbeds]," Alaska Science Forum* Article #674, August 1, 1984.
*[http://homepage.eircom.net/~williamfinnerty/chaplefinnerty/esker/riada1.htm Esker Riada Webpage]
Diagram illustrating (i) tunnel in glacier before retreat of ice, forming (ii) meandering esker in [https://web.archive.org/web/20070711041432/http://www.dcnr.state.pa.us/topogeo/education/es6/es6.pdf The Ice Melts: Deposition*] on page 6 of "Pennsylania and the Ice Age" published 1999 by PA DCNR [https://web.archive.org/web/20160304002357/http://www.dcnr.state.pa.us/topogo Bureau of Topographic and Geologic Survey]
*[https://web.archive.org/web/20081204092736/http://www.bridgenorthesker.ca/ The Bridgenorth Esker: geomorphology and sedimentology]
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