Trouble in the World’s Largest Oil Field-Ghawar (Postscript)

(From the postscript)

As the oil was extracted, a formerly producing well would be turned into an injector (a producer would become an injector), so you will see what it looks like today after lots of producers have been turned into injectors. Water is injected into the carbonate reservoir in order to maintain reservoir pressure and allow the field to be produced at 5 million barrels per day. If the pressure were to drop, the production rate would fall quickly.

G. R. Morton