A system is provided. The system includes a plurality of seismic sensors and a computer device. The computer device is programmed to a) store a plurality of distances between each of the plurality of seismic sensors; b) store one or more fingerprints of a signal to be detected; c) receive a first signal transmitted from a first seismic sensor of the plurality of seismic sensors; d) receive the first signal transmitted from a second seismic sensor of the plurality of seismic sensors; e) compare the first signal to the one or more fingerprints of the signal to be detected; and f) determine a direction of travel of the first signal based on the distance between the first seismic sensor and the second seismic sensor, the first time, and the second time.

A system is provided. The system includes a plurality of seismic sensors and a computer device. The computer device is programmed to a) store a plurality of distances between each of the plurality of seismic sensors; b) store one or more fingerprints of a signal to be detected; c) receive a first signal transmitted from a first seismic sensor of the plurality of seismic sensors; d) receive the first signal transmitted from a second seismic sensor of the plurality of seismic sensors; e) compare the first signal to the one or more fingerprints of the signal to be detected; and f) determine a direction of travel of the first signal based on the distance between the first seismic sensor and the second seismic sensor, the first time, and the second time.

A seismic sensor assembly can include a housing that defines a longitudinal axis; a sensor; sensor circuitry operatively coupled to the sensor; and overvoltage protection circuitry electrically coupled to the housing.

A seismic sensor includes a measurement unit configured to measure acceleration; an earthquake determination unit configured to determine whether or not an earthquake has occurred based on the acceleration measured in a predetermined determination period; an index calculator configured to calculate an index value indicating a scale of an earthquake in an earthquake processing period after the predetermined determination period, when the earthquake determination unit determines that an earthquake has occurred; a continuous earthquake determination unit configured to determine whether or not an earthquake has occurred, based on the acceleration measured in the earthquake processing period; and a shut-off determination unit configured to inhibit output of the shut-off signal regardless of the index value when the continuous earthquake determination unit determines that no earthquake has occurred.

A solid-state hydrophone may include a piezoelectric rod positioned between at least two electrodes. The piezoelectric rod may be disposed within a metallic housing to shield the piezoelectric rod and its connections from acoustic and electromagnetic waves. The piezoelectric rod and the electrodes may be potted in the mechanical housing using a potting material that may be positioned adjacent to the piezoelectric rod. At least a layer of the potting material may be positioned between the piezoelectric rod and the metallic housing to physically separate the piezoelectric rod from the metallic housing.

An apparatus for performing a seismic survey includes a data unit disposed in a housing, a flexible tether connected to the housing at a first end and having a second end, the tether including at least signal carrying wire and a tension conveying member, and an antenna connected to the second end of the tether, the data unit in signal communication with the antenna via the at least one signal carrying wire.

There is described a method of making an acoustic sensor having a frequency response approximating a desired frequency response. The method comprises wrapping optical fiber around a core according to a wrapping pattern. The wrapping pattern is determined from an impulse response of the acoustic sensor. The impulse response is determined from the desired frequency response of the acoustic sensor.

There is described a method of making an acoustic sensor having a frequency response approximating a desired frequency response. The method comprises wrapping optical fiber around a core according to a wrapping pattern. The wrapping pattern is determined from an impulse response of the acoustic sensor. The impulse response is determined from the desired frequency response of the acoustic sensor.

The present disclosure is directed to a system to locate seismic data acquisition units in a marine environment. The system can include a first seismic data acquisition unit. The first seismic data acquisition unit can include a case having a wall defining an internal compartment, a power source, a clock, a seismic data recorder, and at least one geophone disposed within the case. The system can include a flexible connector and a telltale component, wherein the flexible connector and the telltale component can be stored adjacent to the first seismic data acquisition unit, wherein a second seismic data acquisition unit is coupled with the first seismic data acquisition unit.

The present disclosure is directed to a system to locate seismic data acquisition units in a marine environment. The system can include a first seismic data acquisition unit. The first seismic data acquisition unit can include a case having a wall defining an internal compartment, a power source, a clock, a seismic data recorder, and at least one geophone disposed within the case. The system can include a flexible connector and a telltale component, wherein the flexible connector and the telltale component can be stored adjacent to the first seismic data acquisition unit, wherein a second seismic data acquisition unit is coupled with the first seismic data acquisition unit.