A hierarchical early-warning system for landslide probability issues a first level warning based on measured rainfall amounts exceeding a determined threshold, a second level warning, after the first level warning, based additionally on measured soil moisture content measured at different levels, and Factor of safety derived from forecasted pore pressure (FPP) each exceeding a determined threshold, a third level warning, after the first and the second level warnings, based additionally on ground movement measurements compared to a determined threshold, and a fourth level warning after the first, second and third level warnings, based additionally on data from movement-based sensors including strain gauge data.

This invention provides a fiber Bragg grating (FBG) monitoring device for dynamic disasters in coal mines. It includes a data acquisition device, which is used to collect the seismic wave signal in coal mines and reflect the possibility of the current coal and gas outburst hazard through the seismic wave signal described; a data processing device, which is used to process the collected data, eliminate the interferential signal and convert the effective signal into the measured physical quantity, and then send it to the display unit or save it; a real-time processor, which is used to achieve the acquisition and processing of real-time data; a display unit, which is used for the process of acquisition, storage, display and historical data query, and the display of residual capacity; a power supply unit, which is used to provide energy for the whole monitoring device.

A sensor package may include a sensor housing unit and a first sensor that may acquire a first set of measurements within a first measurement range. The sensor package may also include a second sensor configured to acquire a second set of measurements within a second measurement range. The first measurement range and the second measurement range may include an overlapping range used to calibrate the first set of measurements, the second set of measurements, or both.

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.

The present disclosure belongs to the field of geological exploration, and particularly relates to a seismic acquisition system and a sensor based on an MEMS sensor with low power consumption, so as to solve the problem that the existing seismic wave acquisition technology cannot balance high accuracy and low power consumption when the MEMS sensor is used. The present disclosure comprises: the MEMS sensor is used for receiving seismic wave signals and outputting MEMS sensor electrical signals; a common-mode voltage adjustment module is used for adjusting the MEMS sensor signals to be within the input range of common-mode voltage of a readout circuit, so as to obtain low voltage MEMS sensor signals. In the present disclosure, high voltage ensures the detection accuracy of the MEMS sensor; and low voltage is supplied to the readout circuit, thereby reducing the power consumption of the overall seismic acquisition system.

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.

The present disclosure discloses a method of obtaining a seismic while drilling signal. The method comprises the following steps: arranging geophones by using a first observation method to obtain a first seismic reference signal and a second seismic reference signal; arranging geophones by using a second observation method to obtain first seismic data; arranging geophones by using a third observation method to obtain second seismic data; comparing the first seismic reference signal with the second seismic reference signal to obtain a first output reference signal, and optimizing the first output signal to obtain a second output reference signal. The present disclosure obtains square matrix and near-wellhead seismic while drilling data through the combination of geophone square matrix combined observation, near-wellhead observation, and survey line observation, the data acquisition efficiency is relatively high, the signal-to-noise ratio is high, and thus, the problem of near-surface noise interference is effectively solved.

Various embodiments of the present disclosure are directed to systems and methods for data collection using fiber-optic cable in a well, and analysis of the data to determine instantaneous frequency, instantaneous phase, instantaneous amplitude, and/or dominant frequency. These measures can be used to determine parameters associated with the operation of the well. The parameters can be used to control the operation of the well and/or the fracturing process.

A seismic attenuation quality factor Q is determined for seismic signals at intervals of subsurface formations between a seismic source at a marine level surface and one or more receivers of a well. Hydrophone and geophone data are obtained. A reference trace is generated from the hydrophone and geophone data. Vertical seismic profile (VSP) traces are received. First break picking of the VSP traces is performed. VSP data representing particle motion measured by a receiver of the well are generated. The reference trace is injected into the VSP data. A ratio of spectral amplitudes of a direct arrival event of the VSP data and the reference trace is determined. From the ratio, a quality factor Q is generated representing a time and depth compensated attenuation value of seismic signals between the seismic source at the marine level surface and the first receiver.

A low-cost Internet-of-Things (IoT) earthquake early warning (EEW) device can be deployed at homes, business facilities, and field locations to provide on-site warning and alert regional subscribers. The IoT device is integrated with a sensor, such as a geophone, for ground motion sensing, a single board computer, an analog-to-digital converter, an alert, wireless connectivity, and custom-designed packaging. A custom software application can control the device, detect earthquakes, and issue alerts. The device can run automatically and can be managed remotely. A collection of devices can form a network to provide even more lead time in EEW. For example, if one device detects an earthquake in northern Los Angeles metro area and alerts another device/user/subscriber of the warning service in southern Los Angeles, then the latter gets extra warning time because it could take about 5 to 10 seconds for seismic waves to travel from northern to southern Los Angeles.