Methods are disclosed for monitoring operation integrity during hydrocarbon production or fluid injection operations. According to the methods, received microseismic data is processed to obtain a plurality of data panels corresponding to microseismic data measured over a predetermined time interval. For each data panel, trigger values are calculated for data traces corresponding to sensor receivers of the microseismic monitoring system. At least one data panel is selected as a triggered data panel that satisfies predetermined triggering criteria. A value is calculated for each of at least two event attributes of a plurality of event attributes of the event. An event is classified into at least one event category of a plurality of event categories based on the event score. Related non-transitory computer usable mediums are also disclosed.

A timing alignment method for data acquired by monitoring units of a borehole-surface micro-seismic monitoring system includes acquiring two rock-burst waveform data segments with GPS timestamps; calculating a time difference and a number of sampling points between each pair of adjacent GPS timestamps; adding, on an equal-interval basis, a sampling time to a sampling point missing a timestamp between each pair of adjacent GPS timestamps; calculating average sampling frequencies of the two rock-burst waveform data segments, adding, on an equal-interval basis, a sampling time to a sampling point missing a timestamp except first and last GPS timestamps in each of the two data segments; obtaining sampling times of all sampling points, resampling the sampling times according to a uniform sampling frequency; calculating a rock-burst waveform data segment at a new sampling time with a linear interpolation formula, and aligning the sampling times of the two rock-burst waveform data segments.

System, method, and apparatus for classifying fracture quantity and quality of fracturing operation activities during hydraulic fracturing operations, the system comprising: a sensor coupled to a fracking wellhead, circulating fluid line, or standpipe of a well and configured to convert acoustic vibrations in fracking fluid in the fracking wellhead into an electrical signal; a memory configured to store the electrical signal; a converter configured to access the electrical signal from the memory and convert the electrical signal in a window of time into a current frequency domain spectrum; a machine-learning system configured to classify the current frequency domain spectrum, the machine-learning system having been trained on previous frequency domain spectra measured during previous hydraulic fracturing operations and previously classified by the machine-learning system; and a user interface configured to return a classification of the current frequency domain spectrum to an operator of the fracking wellhead.

The present invention discloses a sensing-acquisition-wireless transmission integrated microseismic monitoring system, comprising a sensing unit, wherein the system further comprises an acquisition-wireless transmission unit. The acquisition-wireless transmission unit comprises a flameproof enclosure, an acquisition instrument, a battery, a wireless transmitter and a transmitting antenna. A push nut is arranged at an open end of the flameproof enclosure. A support stage is sheathed on an outer wall of the flameproof enclosure. A connection ring is movably sheathed on the open end of the flameproof enclosure. The push nut is connected to the connection ring. Multiple inner wing elastic plates are circumferentially arranged on the connection ring. The inner wing elastic plates are connected to corresponding expandable plate outer wings, respectively. The present invention further discloses a sensing-acquisition-wireless transmission integrated microseismic monitoring method.

Sound signal when a wave generated by a geo-acoustic event source reaches any monitoring point (S1), constructing a theoretical propagation difference model and an observed propagation difference model of the waveform characterization quantity between monitoring points, to calculate a waveform characterization quantity difference value between two monitoring points (S2); and constructing an objective function based on the theoretical propagation difference model and the observed propagation difference model, and obtaining the location of the geo-acoustic event by means of inversion based on the objective function (S3). According to the geo-acoustic event location method, the arrival time, time domain parameters, spectral information, and waveform shape of the geo-acoustic signal when the wave generated by the geo-acoustic event source reaches any monitoring point are considered, then the non-uniformity of a propagation medium is comprehensively reflected, and the inversion precision of geo-acoustic event location is finally improved.

Disclosed are methods, systems, and computer-readable medium to perform operations including: spectrally decomposing seismic data associated with a target subsurface area into a plurality of iso-frequency volumes; selecting a low-frequency volume and a high-frequency volume from the plurality of iso-frequency volumes; dividing the low-frequency volume by the high-frequency volume to generate a frequency ratio volume for the target subsurface area; establishing a time-depth relationship in the target subsurface area; extracting, based on the time-depth relationship and the frequency ratio volume, an iso-frequency ratio log in the target subsurface area; and using the iso-frequency ratio log to identify a subsurface gas reservoir in the target subsurface area.

A high-power seismic wave early warning method is provided to use an earliest-arriving seismic wave to estimate a maximum power value of a later-arriving high-power seismic wave for a target site. When the estimated maximum power value of the later-arriving high-power seismic wave is greater than a warning value, an earthquake early warning is transmitted to an earthquake early warning device that is located at the target site.

According certain aspects, embodiments of the invention consider the problem of microseismic event localization from a parameter estimation perspective, and include a method and system for computing and displaying characteristics of event localization errors. According to certain other aspects, embodiments of the invention include techniques for deriving aggregate statistics from a set of event location estimates, including methods for computing and displaying the probability that an event occurred in any given volume, and methods for describing and displaying the smallest volume that contains a specified percentage of the event probability or expected to contain the specified percentage of the events.

A fracture mapping system for use in hydraulic fracturing operations utilizing non-directionally sensitive fiber optic cable, based on distributed acoustic sensing, deployed in an observation well to detect microseismic events and to determine microseismic event locations in 3D space during the hydraulic fracturing operation. The system may include a weighted probability density function to improve the resolution of the microseismic event on the fiber optic cable.

This disclosure presents systems, methods, and apparatus for determining cluster efficiency during hydraulic fracturing, the method comprising: measuring acoustic vibrations in fracking fluid in a fracking wellhead, circulating fluid line, or standpipe of a well; converting the acoustic vibrations into an electrical signal in a time domain; recording the electrical signal to memory; analyzing the electrical signal in the time domain for a window of time and identifying two amplitude peaks corresponding to a fracture initiation; measuring a time between the two amplitude peaks; dividing the time by two to give a result; multiplying the result by a speed of sound in the fracking fluid to give a distance between the fracture initiation and a plug at an end of a current fracking stage of the well; and returning a location of the fracture initiation to an operator based on the distance between the fracture initiation and the plug.