método para medir propriedades de uma formação com um furo de sondagem que se estende através da mesma

Apparatus and methods for measuring properties of formation material and fluid in a borehole wall. In some embodiments, the apparatus includes a cylinder with a drawdown piston slideably disposed therein, a probe assembly and a passageway configured to provide fluid communication between the probe assembly and the cylinder. The probe assembly has a housing, a piston slideably disposed within the housing, the piston having a throughbore and a pad coupled thereto, and a tubular slideably disposed within the throughbore. The drawdown piston is translatable from a first position toward a second position to draw fluid into the probe assembly, the passageway and the cylinder, and translatable from the second position toward the first position to increase pressure of fluid in the passageway.