Detection system for detecting discontinuity interfaces and/or anomalies in pore pressures in geological formations

A detection system for detecting discontinuity interfaces and/or anomalies in pore pressures in geological formations comprising:

• a drill bit for drilling the subsoil in which one or more electro-acoustic transducers configured to operate as a transmitter and a receiver, are integrated;
• analogue driving electronic circuits configured to control the electro-acoustic transducer, which acts as a transmitter and analogue receiving electronic circuits for amplifying and processing the signal received from the electro-acoustic transducer acting as a receiver;
• a processing and control unit associated with the analogue driving and receiving electronic circuits, said processing and control unit being associated with a data storage unit and is powered electrically by an electrical supply system, said processing and control unit being configured for generating driving signals to be sent to the electro-acoustic transducer acting as a transmitter by means of said analogue driving electronic circuits, for acquiring the signals received from the electro-acoustic transducer acting as a receiver by means of said analogue receiving electronic circuits and for processing said received signals in such a way as to determine the presence of discontinuity interfaces and/or anomalies in pore pressures in geological formations;
• wherein each of said electro-acoustic transducers is adapted to be in contact with a pressurised fluid and is of the type comprising:
• a tubular body, which extends in length along a longitudinal direction X, said tubular body comprising a first end portion and a second end portion, opposed to each other longitudinally, said tubular body having internally a first chamber, which ends with the first end portion and a second chamber on one side adjacent and in fluid communication with said first chamber and, on the other side ending with said second end portion, said first end portion being closed towards the outside by means of a membrane applied to said tubular body, said second end portion having one or more openings that put it into fluid communication towards the outside of said tubular body, said first chamber containing in its walls a plurality of electrical windings arranged in succession between them in the longitudinal direction X, said second chamber being filled with a liquid;
• a movable element housed in said first chamber, said movable element comprising a plurality of permanent magnets packed and arranged one above the other with alternate magnetisation in the longitudinal direction X, and separated one from the other by discs of ferromagnetic material, said movable element being supported at the longitudinal ends by springs, said movable element also being connected to said membrane;
• and
• a movable piston positioned and slidable in the second end portion.