A method for processing seismic data may include receiving, via a processor, the seismic data acquired via a seismic survey. The seismic survey may include seismic sources that emit seismic wavefields at different locations. Each of the seismic sources may change a directivity pattern of a respective seismic wavefield based on a respective location of the respective seismic source. The seismic survey may also include seismic receivers that may receive the seismic data. The method may also include generating one or more basis functions that correspond to measurements of the seismic data, modelling a signal component of the seismic data as a sum of the one or more basis functions, and storing the signal component in a storage component. The signal component may be used to acquire an image of a subsurface region of the earth for identifying a feature in the subsurface region of the earth.

A non-invasive method and system for reliably locating underground pipes, particularly non-metallic pipes. The invention uses portable seismic generator to direct seismic waves into the earth at a downrange sampling location suspected to overlie a buried section of pipe. The seismic waves are imbued with a distinctive attribute, such as a predetermined frequency or digital pulse. Upon encountering the pipe, seismic waves are efficiently converted to longitudinal waves which are conducted lengthwise along the pipe to an accessible region. A receiver coupled to the accessible region is tuned to detect vibrations that carry the distinctive attribute. The receiver wirelessly transmits data indicative of the intensity of detected vibrations to a remote communicator which may be attached directly to the seismic generator. By sampling several locations in near vicinity, the most probable location of the buried pipe can be deduced.

A device (110) for performing measurements on a seabed (3), comprises a chamber (111) containing a sensor (120) and a fluid (115) at a constant temperature and at an ambient pressure. This removes the need for calibration in large ranges of both pressure and temperature. In addition, this eliminates the need to wait until the sensor (120) has achieved ambient temperature, and thereby achieves a desired accuracy of the recordings from the sensor while decreasing the operation time. The device preferably comprises an insulating layer (113), an internal temperature stabilising device (130) and a circulating device (131) to ensure a constant temperature and low temperature gradients within the chamber (111). The pressure within chamber (111) may be equalised to ambient pressure by a pressure inlet (112).

A multimode seismic unit can selectively operate in any one or more of multimode readout modes. In one embodiment, a multimode seismic unit (1600) includes a physical mode selector switch (1602). The mode selector switch (1602) allows for manual selection of output modes including wireless, nodal, dual mode or automatic mode selection. The unit (1600) further includes an antenna (1604) for RF transmissions and a data port (1606) for uploading data in a nodal mode. The multimode unit can be used to implement a variety of single mode and multimode seismic arrays.

One or more first sensors may be configured to sense seismic signals and one or more second sensors may be configured to sense electromagnetic crosstalk signals. The second sensors are not responsive to the seismic signals. The data from the first and second sensors may be recorded as first data and second data, respectively. The first data may be modified based on the second data to remove the electromagnetic crosstalk noise form the seismic data.

Methods and systems for characterizing fractures in a subterranean formation are provided. The method includes introducing an encapsulated explosive unit into a casing located in a wellbore within the subterranean formation and maintaining the encapsulated explosive unit in a stage of the casing. The method also includes detonating the encapsulated explosive unit within the stage to generate a pressure wave that passes through a group of perforations and into the fractures and measuring a reflected pressure wave using a pressure sensor coupled to the bridge plug to produce a pressure measurement. The method further includes converting the pressure measurement into an acoustic signal correlated with the pressure measurement by an acoustic signal generator contained in the bridge plug and transmitting the acoustic signal to apply acoustic pressure on a fiber optic cable coupled to an exterior surface of the casing.

Provided is an earthquake response system using a seismic motion sensor. The seismic motion sensor of the earthquake response system includes: a sensor unit measuring a sensor value including peak ground acceleration (PGA) of the ground due to shaking; a seismic motion sensing unit sensing seismic motion on the basis of a seismic motion sensing result value calculated from an artificial neural network that uses the peak ground acceleration as input when the peak ground acceleration satisfies a seismic motion sensing condition; a seismic motion determiner determining generation of final seismic motion on the basis of a seismic motion determination parameter calculated from the sensor value on the basis of the seismic motion sensing result; a shaking grade calculator calculating a shaking grade of the determined final seismic motion through the peak ground acceleration; and a communication unit notifying the shaking grade of the final seismic motion.

The probe includes a hollow casing defining a closed inner compartment, the hollow casing having at least an end to be placed in contact with the ground; at least a sensor received in the closed inner compartment, the sensor being able to sense a physical quantity related to the ground; and at least an emitter received in the closed inner compartment, the emitter being able to send data representative of the physical quantity sensed by the sensor. Also, at least a power source received in the closed inner compartment, the power source being able to power the sensor and/or the emitter. At least part of the sensor and/or at least part of the emitter is biodegradable.

A multimode seismic survey system is disclosed where seismic information for a given seismic survey is read out by different seismic units using different modes. Such multimode systems encompass hybrid arrays where information is read out via different output modes for a single seismic event, and other multimode arrays where seismic information is read out via different modes for different seismic events. The modes utilized in such arrays may include wireless, nodal and/or cable modes. The multimode arrays can be implemented using multimode seismic units or single mode seismic units. In any event, the multimode arrays can be utilized to achieve a combination of advantages associated with the different readout modes or to address any of various multimode mode contexts in relation to seismic surveys.

Apparatus and methods of identifying rock properties in real-time during drilling, are provided. An apparatus includes an acoustic sensor installed in a drilling fluid circulation system of a drilling rig, the acoustic sensor coupled to one of the following: (i) a bell nipple, (ii) a gooseneck, or (iii) a standpipe. Raw acoustic sensor data generated real-time as a result of rotational contact of the drill bit with rock during drilling is received, and a plurality of acoustic characteristics are derived from the raw acoustic sensor data. The lithology type of rock undergoing drilling may be determined from the acoustic characteristics. Petrophysical properties of the rock undergoing drilling may be determined using a petrophysical properties evaluation algorithm employable to predict the petrophysical properties of rock undergoing drilling from the raw acoustic sensor data.