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57:. In caves prone to flooding, a narrow and contorted path through a boulder choke can fill up with water quickly, preventing progress. In 1972, ten members of the University of Leeds Speleological Association were trapped behind a complex flooded boulder choke in
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Boulder chokes can be formed by rockfall, stream deposition, or mining debris. Due to the nature of their formation boulder chokes may be unstable and can prove difficult to navigate and map due to their complexity.
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became the longest cave in the UK when cavers succeeded in clearing a route through a boulder choke for 140 metres (460 ft) to connect two known cave systems, an exercise that took three years.
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Boulder chokes can be hazardous, as unstable boulders can unexpectedly move, potentially crushing or trapping cavers. In May 1988, for example, three cavers were killed in a boulder choke in
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In order to clear a boulder choke the rocks obstructing the passage may need to be removed, often requiring breaking up first either mechanically or using a small explosive. The
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is a collection of large rocks or rubble that obstructs a shaft or passage in a cave or mine. In order to progress through passages
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78:"The Cave of The Wild Horses, Kilcorney, Co. Clare, Ireland - The 1983 Extensions"
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Collection of large rocks or rubble that obstructs the passage of a cave or mine
154:"Three Counties System Connects to Create UK's First 100 Kilometre Cave System"
221:
Monico, Paul (1989). "Diving in the
Dementor Sump and "The Rescue" 1972".
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182:
Boothroyd, Colin (June–July 1988). "Easegill
Tragedy".
132:"Potholers break through the final Three Counties link"
39:often need to negotiate or clear boulder chokes.
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61:, resulting in a 44-hour-long trip.
23:A caver clearing a boulder choke in
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130:Wainwright, Martin (7 Nov 2011).
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223:ULSA Explorations Journal II
104:Craig, David; Daley, Jason.
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202:www.mlcmac.talktalk.net
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106:"How Low Can You Go?"
48:Three Counties System
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55:Ease Gill Caverns
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33:boulder choke
27:, Gaping Gill
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166:. Retrieved
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88:. Retrieved
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158:Caving News
207:2015-04-21
168:2015-04-21
116:2015-04-21
90:2015-04-21
65:References
186:(82): 12.
112:. Outside
25:Stile Pot
236:Category
225:: 39–42.
184:Descent
138:3 April
242:Caving
37:cavers
81:(PDF)
140:2017
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31:A
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
