Investigation and remediation of active-clay contaminated sepiolite drilling muds

摘要

Unconventional gas and oil development has gained remarkable attention in recent years. However, the high content of active clays in shales makes drilling difficult. Since most formations drilled for oil and gas exploration are shales, active solid dispersion into the drilling mud is a common problem. This might results in severe problems, such as stuck pipes, circulation loss, excessive torque and drag, inadequate cuttings transport, poor log quality, poor primary cement job, and borehole instability.