Total Losses and Requirement for Continuous Fill-Up
When drilling through depleted and/or fractured reservoirs, total losses are a common occurrence. In the worst case, if the well penetrates the top of the formation (fracture) above the gas-oil contact there is a high risk of a blowout if insufficient fluid is not pumped down the annulus at all times between encountering total losses and cementing/landing the production casing.
If gas bubbles enter the well bore above the loss zone when drilling, tripping, logging or running casing and insufficient fluid is not pumped down . . .