FIELD: oil and gas industry.
SUBSTANCE: invention relates to a tool assembly for performing tests for determining formation stress in an open section of a wellbore. The tool assembly contains at least two means for isolating the wellbore, located with an axial distance between them to create an isolated section on the open section of the wellbore. The pumping device is made with the possibility of fluid communication with the isolated section and with the possibility of changing the pressure inside the isolated section. The pressure sensor is configured to measure the pressure inside the isolated area. The control unit is designed to control the test sequence. The acoustic shock-wave device is configured to generate a series of electrically induced acoustic shock waves and focus said electrically induced acoustic shock waves on the wellbore wall region to gradually pierce the perforation tunnel from the wellbore into the formation in the direction of propagation of the electrically induced acoustic shock waves. The acoustic shock wave subassembly is designed to drive an acoustic shock wave device. A method for performing tests for determining formation stress in an uncased section of a wellbore is claimed.
EFFECT: improving the quality and reliability of the formation stress measurement results by providing a perforation tunnel, which improves the communication path for the formation fluid.
17 cl, 12 dwg
