A reaction mass seismic survey source that is located in an underground casing. The seismic source includes a non-planar base plate; a reaction mass located on the non-planar base plate; and a flextensional element housed in a recess of the reaction mass and configured to vibrate the non-planar base plate when actuated, to generate seismic waves underground.

A method and a device for locating an optical fiber buried in a volume. More particularly, the method includes at least: determining a position of the optical fiber, based on at least one detection level of a source of radiation for at least one position of the source, provided by a detection device connected to the optical fiber.

A method and a device for locating an optical fiber buried in a volume. More particularly, the method includes at least: determining a position of the optical fiber, based on at least one detection level of a source of radiation for at least one position of the source, provided by a detection device connected to the optical fiber.

Methods and systems for training a machine learning (ML) network to predict a likelihood of a presence of a geological fracture from an observed drill-bit seismic dataset are disclosed. The method may include obtaining, using a seismic processing system, a plurality of geophysical models, where each geophysical model includes a location of a drill bit. The method may further include simulating, for each geophysical model a corresponding simulated drill-bit seismic dataset for seismic waves emanating from the drill bit and recorded by at least one seismic receiver and forming a training dataset including a plurality of training pairs, with each training pair including a geophysical model from the plurality of geophysical models and the corresponding simulated drill-bit seismic dataset. The method may still further include training, using the training dataset, the ML network to predict the likelihood of the presence of the geological fracture from the observed drill-bit seismic dataset.

Methods and systems for training a machine learning (ML) network to predict a likelihood of a presence of a geological fracture from an observed drill-bit seismic dataset are disclosed. The method may include obtaining, using a seismic processing system, a plurality of geophysical models, where each geophysical model includes a location of a drill bit. The method may further include simulating, for each geophysical model a corresponding simulated drill-bit seismic dataset for seismic waves emanating from the drill bit and recorded by at least one seismic receiver and forming a training dataset including a plurality of training pairs, with each training pair including a geophysical model from the plurality of geophysical models and the corresponding simulated drill-bit seismic dataset. The method may still further include training, using the training dataset, the ML network to predict the likelihood of the presence of the geological fracture from the observed drill-bit seismic dataset.

A generator of acoustic waves for submarine environments has a hollow body that extends along an axis delimited by a first closed end and by a second end that is provided with an acoustic diffuser member. The hollow body has a first cylindrical portion delimited by the first end that houses a first piston and a second cylindrical portion delimited by the second end that houses a second piston in a freely axially sliding manner. The second piston is mechanically free from the first piston and has a face that faces the acoustic diffuser member. An impulsive actuator is configured together with the first piston to move the first piston towards the second piston. An adjustor for a longitudinal motion of the second piston is arranged between the first piston and the second piston.

A generator of acoustic waves for submarine environments has a hollow body that extends along an axis delimited by a first closed end and by a second end that is provided with an acoustic diffuser member. The hollow body has a first cylindrical portion delimited by the first end that houses a first piston and a second cylindrical portion delimited by the second end that houses a second piston in a freely axially sliding manner. The second piston is mechanically free from the first piston and has a face that faces the acoustic diffuser member. An impulsive actuator is configured together with the first piston to move the first piston towards the second piston. An adjustor for a longitudinal motion of the second piston is arranged between the first piston and the second piston.

A vibrator truck includes a vehicle and a vibration assembly mobile relative to each other by a lift system having at least one footbase and configured to lift up/down the vibration assembly. The lift system includes at least one flexible strap and a coupling device configured to couple the at least one flexible strap to the vibratory part and the at least one footbase.

A system and method for detecting underground inhomogeneities, the system including at least one transmitting transducer arranged to transmit pre-selected acoustic signals of at least 2 Watts into the ground; at least three receiving transducers disposed at a selected distance from the transmitting transducer and arranged to receive acoustic signals transmitted by the transmitting transducer and reflected by an inhomogeneity in the ground, one of the receiving transducers being disposed in proximity to the transmitting transducer; and a processor; each receiving transducer being coupled to the processor and arranged to transfer the received signals to the processor; the processor configured to process the received reflected acoustic signals and determine, from characteristics of the signals and from the selected distance between the transmitting transducer and the receiving transducer, at least one of: the existence of an underground inhomogeneity; the distance from the receiving transducer to the underground inhomogeneity; the direction from the receiving transducer to the underground inhomogeneity; the acoustic impedance of the underground inhomogeneity; and a signature of the underground inhomogeneity.

A method for selecting parameters of a seismic source array comprising a plurality of source elements each having a notional source spectrum is described, the method comprising calculating a ghost response function of the array; calculating directivity effects of the array; and adjusting the parameters of the array such that the directivity effects of the array are compensated by the ghost response to minimize angular variation of a far field response in a predetermined frequency range. A method for determining a phase center of a seismic source array is also related, the method comprising calculating a far field spectrum of the array at predetermined spherical angles, and minimizing the phase difference between the farfield spectra within a predetermined frequency range by adjusting a vertical reference position from which the spherical angles are defined.