Logging the Chalk

Chalk has proved to be one of the more difficult rocks to corelog as it breaks up readily during the drilling process leading to core-loss and destructuring, particularly where flints, nodular chalks, and/or fractures are present. One of the greatest difficulties is the identification of chalk engineering grade which relies heavily on fracture aperture. Obtaining the correct grade to define the depth of weathering and the depth at which fractures become closed is essential whether for tunne...