Pressure shale
Encyclopedia
Pressure shale is shale
that has been exposed to high pressures that causes it to fracture, usually into large concave pieces. In mud logging
, watching for this type of shale is one method of monitoring for the possibility of drilling into high pressures that might cause a blowout
.
Shale
Shale is a fine-grained, clastic sedimentary rock composed of mud that is a mix of flakes of clay minerals and tiny fragments of other minerals, especially quartz and calcite. The ratio of clay to other minerals is variable. Shale is characterized by breaks along thin laminae or parallel layering...
that has been exposed to high pressures that causes it to fracture, usually into large concave pieces. In mud logging
Mud logging
Mud logging, also known as hydrocarbon well logging, is the creation of a detailed record of a borehole by examining the bits of rock or sediment brought to the surface by the circulating drilling medium . Mud logging is usually performed by a third-party mud logging company...
, watching for this type of shale is one method of monitoring for the possibility of drilling into high pressures that might cause a blowout
Blowout (well drilling)
A blowout is the uncontrolled release of crude oil and/or natural gas from an oil well or gas well after pressure control systems have failed....
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