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A Geoscience Digital Image Library

2984.jpg
TitleCalcite fill in a boudin neck
DescriptionEnigma!!! The calcite fill of this boudin neck is part of the abundant evidence for the presence of lithostatic fluid pressure in the Ordovician Cloridorme Formation of the Gaspe Peninsula, Quebec, during folding and thrusting. During hydraulic fracturing, the slab of graywacke hanging down from the top of the fill must have rotated clockwise in order for the “elephant trunk” appendage of graywacke attached to the bottom of the bed to rotate ccw out from behind it. While the sequence can be deciphered, the pieces don't fit back together owing to some combination of late protusion in from the top and bottom and possible out-of-section movements.
ChronostratigraphyOrdovician
LithostratigraphyCloridorme Formation
LocationCanada ▹ Quebec. Gaspe Peninsula.
PhotographerEdward Beutner. 1995.
CollectionKeck Structural Geology Slide Set #EB5.
Key wordsgraywacke, Quebec, boudin, fracturing
Tech details429 KB. Outcrop.
GeoDIL number2984