Zion Oil & Gas Inc (ZNOG)

[BlissBull]

"High-pressure production zones"...

"Fluids cannot flow uncontrolled up the center of the drillstring during a kick because of the kelly cock... Where fluids can flow up the well is along the outside of the drillstring in the space called the annulus... After a kick is detected, the well is killed (flow from the well is stopped) by throwing the blowout preventers... Heavier drilling mud (kill mud) is pumped into the well through the choke manifold, kill line, and a one-way valve in the blowout preventer stack (kill connection) to circulate the kick out of the well... The abnormal high-presure zone is then drilled, and protection casing (steel pipe) is run and cemented into the well to isolate the zone."

Nontechnical Guide to PETROLEUM Geology, Exploration, Drilling & Production
Third Edition
Norman J. Hyne, Ph.D.