METHODS AND APPARATUS FOR TESTING EARTH FORMATIONS

摘要

In the representative embodiments of the new and improved methods and apparatus for testing earth formations disclosed herein, fluid-admitting means are placed into sealing engagement with a potentially-producible earth formation and selectively-operable valve means are rapidly opened to place a low-pressure chamber and a flow line in the tool into communication with the isolated formation to remove plugging materials from a filtering medium ahead of the flow line before connate fluids are inducted into the tool as well as to obtain one or more preliminary pressure measurements which are indicative of the potential success of the testing operation and the possible nature of the earth formation.