its on team, page-40

I checked the technical manual (Wikipedia) for 'gas kick'.

Interesting stuff. Obviously, the operating procedures Eni had in place worked correctly, but, if sounds like things could easily have got nasty if the operators weren't on the ball.

If they can tame the beast, the rewards could be fantastic......





Formation kick[edit source]
The downhole fluid pressures are controlled in modern wells through the balancing of the hydrostatic pressure provided by the mud used. Should the balance of the drilling mud pressure be incorrect then formation fluids (oil, natural gas and/or water) begin to flow into the wellbore and up the annulus (the space between the outside of the drill string and the walls of the open hole or the inside of the last casing string set), and/or inside the drill pipe. This is commonly called a kick. If the well is not shut in (common term for the closing of the blow-out preventer valves), a kick can quickly escalate into a blowout when the formation fluids reach the surface, especially when the influx contains gas that expands rapidly as it flows up the wellbore, further decreasing the effective weight of the fluid. In other petroleum engineering words, the formation pore pressure gradient exceeds the mud pressure gradient, even in some cases when the Equivalent Circulating Density ECD is imposed with the mud pumps on the rig.
Additional mechanical barriers such as blowout preventers (BOPs) can be closed to isolate the well while the hydrostatic balance is regained through circulation of fluids in the well.
Early warning signs of a well kick are:
Sudden change in drilling rate;
Change in surface fluid rate;
Change in pump pressure;
Reduction in drillpipe weight;
Surface mud cut by gas, oil or water;
Connection gases, high background gas units, and high bottoms up gas units in the mudlogging unit.
[19]