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Unformatted text preview: t called in a sand section because placing the casing shoe – the section of the casing between the bottom of the wellbore and the float valve – in a laminated sand‐shale zone increases the likelihood of cement channeling or contamination due to washout, and creates difficulties in logging well data. 80 Figure 3 depicts the placement of the Macondo well shoe track. Id. BP’s September 2009 Pre‐Drilling Data Package also indicated that, if after drilling the primary M56 objective there was an onset of pressure requiring a new casing string, no further drilling would be feasible. See BP‐HZN‐MBI00013494. 78 Sand is more permeable than shale. Therefore, when casing is set in sand, lost returns are more likely. 79 BP‐HZN‐MBI00013494. 80
Cement channeling occurs when the cement slurry in the annulus does not rise uniformly, leaving spaces and therefore preventing a strong bond. 77 35 ML @ 5067' MD/TVD 36" @ 5,321' MD/TVD (254' bml) 9 7/8” Liner 17,168’
28" @ 6217' MD/TVD (1150' bml)
7,567' MD - Bo...
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