Abstract: A seismic survey uses a central control and a seismic source. The seismic source has a vibrator that acoustically couples to the ground using a moveable pad. A method for performing a seismic survey includes sending a first message from the seismic source to the central control indicating a time at which the pad is being lowered; estimating a time at which the pad will be acoustically coupled to the ground based on the first message; and sending a message from the central control to the seismic source to begin a sweep, the sweep beginning no sooner than the estimated time. Another method includes: mapping a surface of a terrain to be traversed by the truck using at least one sensor carried by the truck; positioning a moveable pad based on the mapped surface to provide a physical gap between the surface and the moveable pad; and traversing the mapped terrain with the truck.

Abstract: A nodal seismic unit for acquiring seismic information includes an enclosure, a GPS receiver disposed in the enclosure; a motion sensor disposed in the enclosure; a LPWAN radio transceiver disposed in the enclosure; and a control unit disposed in the enclosure. The control unit is configured to transmit an unplanned movement signal to a remote operator using the LPWAN radio transceiver if the control unit receives a signal from the motion sensor indicative of an acceleration greater than a preset level. Additionally, he control unit may be configured to change an operating state of the nodal seismic unit in response to detecting a predetermined pattern of motion using the motion sensor.

Abstract: 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.

Abstract: A seismic source includes a base plate having a bottom surface contacting a surface of the ground. The coupler is connectable to the bottom surface of the base plate and projects downward from the base plate. The coupler contain soil under the base plate during operation. Another seismic source includes a base plate and at least one contact member. The base plate has an upper surface engaging the seismic source, a lower surface configured to contact a soil surface. The contact member projects from the lower surface and has a planar bottom surface with a surface area less than a surface area of the base plate lower surface.

Abstract: A seismic source includes a base plate having a bottom surface contacting a surface of the ground. The coupler is connectable to the bottom surface of the base plate and projects downward from the base plate. The coupler contain soil under the base plate during operation. Another seismic source includes a base plate and at least one contact member. The base plate has an upper surface engaging the seismic source, a lower surface configured to contact a soil surface. The contact member projects from the lower surface and has a planar bottom surface with a surface area less than a surface area of the base plate lower surface.

Abstract: Methods, systems, and devices for conducting a seismic survey. The system includes a seismic sensor supplying a seismic signal; sampling circuitry configured to convert the signal to a sequence of samples, each sample represented by a bit string; a data communication device configured to transmit compressed seismic data; a recording computer configured to receive compressed seismic data; at least one processor with a computer memory accessible thereto, the at least one processor configured to: create a sample block by storing at least a portion of the sequence of samples in memory units in the computer memory, wherein each sample is stored in a corresponding memory unit; and compress data contained in the sample block by encoding all bits of a particular bit number from the memory units of the sample block in sequence to produce compressed seismic data.

Abstract: Methods, apparatuses, and systems are disclosed for multi-station sensor strings. One example apparatus includes a sensor string. The sensor string includes a connector and a common data transmission channel configured to be in communication with a data acquisition unit through the connector. The sensor string also includes a first seismic sensor configured to provide sensed seismic data to the common data transmission channel, and a second seismic sensor also configured to provide sensed seismic data to the common data transmission channel.

Abstract: A connector for a cable having a core stress member surrounded by a secondary stress member may include a connector body, a wedge, a retainer, a molded body, and a collar. The connector body may have at least one flow channel formed on an inner surface of the distal end and at least one radial hole providing fluid communication to the at least one flow channel. The wedge is disposed in a pocket of the connector body and is attachable to the core stress member. The molded body surrounds the distal end, fills the at least one flow channel, and attaches to the secondary stress member. The collar may at least partially enclose the connector body.

Abstract: Methods, systems, and devices for conducting a seismic survey. The system includes at least one seismic sensor configured to supply a signal responsive to reflections of acoustic energy from an earth surface; and at least one processor configured to: mitigate sensor offset from a sequence of samples representative of the signal by filtering the sequence of samples using a symmetrical-in-time finite impulse response (FIR) filter. The FIR filter may approximate a sinc-in-frequency filter. The at least one processor may be configured to process the sequence of samples using a plurality of filter stages that are rectangular in time. The length of one filter stage of the plurality of filter stages may be different than the length of another filter stage of the plurality of filter stages.

Abstract: A seismic source signal apparatus for generating a seismic source signal may include a seismic source component for coupling a reaction mass to the earth; a controllable valve operatively connected to the seismic source component; and a controller controlling the controllable valve with a primary control signal generated by using a model of a response of the controllable valve over a selected operating range. The model is used to reduce nonlinearity in flow versus displacement response of the controllable valve.

Abstract: A method of performing a seismic sweep determining a user-defined force at a frequency using user defined inputs; determining a maximum force at the frequency using sweep parameters; and using the maximum force to drive a seismic source if the user-defined force is greater than the maximum force.

Abstract: A method of controlling seismic data acquisition may include sending a first message to place a plurality of energy sources into an operating mode; sending a second message to place at least one of plurality of energy sources into a non-operating mode; and sending a third message from at least one energy source to a controller.

Abstract: The present disclosure relates to methods and apparatuses for reducing propagation delay uncertainty while conducting a survey. The apparatus includes a plurality of nodes along a communication path configured to allow communication between nodes with only one clock domain boundary crossing. Each node may include a clock, a memory, and a processor. The plurality of nodes is arranged in a linear topology. The linear topology may have first and second nodes on the ends of the line. The method may include reducing propagation delay uncertainty using at least one time marker transmitted to each of the plurality of nodes without crossing a clock domain boundary of any other node.

Abstract: A method of controlling a seismic vehicle may include estimating at least one orientation parameter for the seismic vehicle and controlling at least one operating parameter in view of the estimated orientation parameter(s). In non-limiting arrangements, the control may relate to re-positioning the seismic vehicle, adjusting value of a hold-down force or target drive force, and/or updating a seismic data acquisition database.

Abstract: A method of controlling seismic data acquisition includes synchronizing a sampling rate of at least one node configured to acquire seismic data with a GPS timing signal from a first GPS seismic device; and delaying sending a start signal to one or more seismic sources, the delay being with reference to a GPS timing signal from a second GPS device.

Abstract: The present disclosure relates methods and apparatus for conducting a seismic survey using a fiber optic network. The method may include synchronizing a plurality of seismic devices over a fiber optic network where at least one of the seismic devices is separated from a master clock by at least one other seismic device. The method may also include encoding the master clock signal, transmitting the encoded master clock signal, and recovering the master clock signal. The apparatus may include a fiber optic network with seismic devices. The seismic devices may be arranged in a linear or tree topology.

Abstract: The present disclosure relates methods and apparatus conducting a seismic survey. The apparatus includes an analog interface and power supply both disposed in a housing. The analog interface is configured to receive analog seismic data from a seismic sensor. The apparatus includes one or more of: (i) an isolation transformer disposed between the power supply and the analog interface and (ii) a analog interface clock configured to synchronized with a power supply clock. The method may include reducing power transmission losses and/or the effect of power supply noise on the seismic signals.

Abstract: The present disclosure relates methods and apparatus conducting a seismic survey while supplying power and data over multiple conductor pairs. In aspects, the disclosure also relates to maintaining power distribution during a failure of at least one conductor pair. The method includes superimposing data and power on each of a plurality of conductor pairs. The apparatus may include a power supply with power supplied by the plurality of conductor pairs carrying power and data.

Abstract: A method of performing a seismic sweep includes forming a composite force profile; constructing a target seismic frequency sweep using the composite force profile; and operating a seismic source using the constructed target frequency seismic sweep.

Abstract: A connector for forming an electrical connection includes a connector body and an insulator disposed in the connector body. The insulator includes a plurality of female contacts and a plurality of passages. Each passage allows access to one of the female contacts and is at least partially defined by a plurality of inwardly projecting rings. The connector also includes a plug having a plurality of male contact male contacts complementary to the female contacts. Each male contact male contact has a tower shaped to sealingly seat within an associated passage in the insulator.