Chinese Academy of Sciences

Wenxiu Zhang

Qingyun Di

Yongyou Yang

Wenxuan Chen

Jian Zheng

Yuntao Sun

Fei Tian

Zhongxing Wang

Wenhao Zheng

Zili Wang

Renzhong Pei

Xinzhen He

Jiansheng Du

Yuliang Wang

Jing Ou

Tianxin Zhang

Jiangyun Zhang

Wei Liu

Xiaolong Li

Yali Zhang

Qihui Zhen

Changchun Yang

Hui Wu

Fuqiang Wei

Jiwen Xiao

Jianguang Liu

Jing Liu

Hong Li

Yujie Yang

Zongwei Li

Binbin Chen

Muming Xia

Canyun Wang

Wenqiang Yuan

Shujun Wu

A method of encoding and decoding downlink instructions based on mud flow rate includes an encoding method and a decoding method. The encoding method and the decoding method are configured to transmit and receive instructions by controlling the mud flow rate during drilling process. The method of encoding and decoding downlink instructions based on mud flow rate does not require a fixed threshold of voltage as a judgement standard for '0' and “1” symbols, but uses voltage change rate as a standard for judging the level transition, avoiding decoding failure caused by the inability of voltage sampling values to reach the fixed threshold after well depth is increased.

Method of encoding and decoding downlink instructions based on mud flow rate

A service table for polling data of downhole transmission devices in MWD includes a frame number, a number of data items of a data frame, a number of cycles of the data frame in a polling process, a device address of each of the data items, a measurement parameter, a valid bit number, a valid byte number of the data frame, a total frame number, a total polling frame number H and a total polling frame number L, an error polling frame number H and an error polling frame number L, and a transmission status bit flag. The service table architecture for polling data of a downhole transmission device in MWD has been used in actual drilling devices and has completed field operations for multiple wells. Compared to the simplified service tables in the past, the service table can support multiple downhole transmission devices working simultaneously, which has improved drilling efficiency and saved drilling costs.

Service table for polling data of downhole transmission device in measurement-while-drilling

The present disclosure provides a phase-controlled excitation downhole nuclear magnetic resonance imaging device and method which relate to the technical fields of downhole nuclear magnetic resonance imaging devices and methods, and achieve high-resolution imaging for an underground target by utilizing a plurality of array antenna units and a phase-controlled array technology. The array antenna units are uniformly arranged around an array antenna frame, and each antenna unit is capable of achieving independent transmission and collection. A transmission phase of each antenna unit is controlled by adopting a phase control technology, the positioning excitation of a transmission pulse is achieved according to a co-phase stacking principle, and thus, the imaging resolution is further improved. The present disclosure has the advantages of high resolution and high efficiency and is suitable for the field of underground exploration. The application of this method will provide a more accurate and reliable imaging result for underground exploration and provide an important technical support for resource exploration and development.

Phase-controlled excitation downhole nuclear magnetic resonance imaging device and method

The present disclosure relates to the technical field of acoustic detection while drilling, in particular to a method and a device for identifying near-bit lithology based on intelligent voiceprint identification, including acquiring rock sound data; pre-processing the acquired rock sound data; extracting voiceprint features of pretreated rock sounds; establishing a rock voiceprint feature database; training the intelligent voiceprint identification algorithms according to the lithology labels and voiceprint feature data in the rock voiceprint feature database; intelligently identifying or predicting the rock voiceprint features using the intelligent voiceprint identification algorithms and outputting the lithology identification results. The present disclosure can greatly enhance the real-time availability and accuracy of obtaining near-bit stratum lithology data in-site, which can effectively improve the reservoir drilling rate and timely avoid drilling risks.

Method and device for identifying near-bit lithology based on intelligent voiceprint identification

The present application discloses a carrier wave distortion compensation method for an MWD mud continuous wave system, comprising: in the downhole, modulating the carrier wave according to the transmission data to obtain a mud continuous wave signal to be transmitted; transmitting the mud continuous wave signal to the ground via a mud channel; denoising the received pressure signal on the ground to obtain a denoised mud continuous wave signal; performing subsequent processing on the denoised mud continuous wave signal to obtain the final transmission data; and performing downhole distortion compensation before modulating the carrier wave or performing ground distortion compensation on the denoised mud continuous wave signal before performing subsequent processing. The present application reduces the bit error rate of the MWD mud continuous wave system by performing waveform distortion compensation prior to downhole modulation or during performing signal processing on the ground.

Method for carrier distortion compensation in MWD mud pulse telemetry

Disclosed is a synchronization method for an MWD mud pulse telemetry system. The method comprises: determining a synchronous training sequence on the basis of a frame structure of downhole sent data; constructing a correlation between the down-hole sending synchronous training sequence waveform and the uphole synchronous training sequence local waveform by means of the irrelevance of the trigonometric function; and performing correlation calculation on the synchronous training codeword waveform, which is received uphole and is subjected to the first modulation, and the synchronous training sequence local waveform, which is subjected to the second modulation, so as to obtain a correlation curve, and finding a synchronous position by means of the correlation curve.

Synchronization method for an MWD mud pulse telemetry system

A noise reduction measurement method of acoustic while drilling data based on signal synchronization is provided. The method performs pre-sampling before effective excitation of a low-frequency pulser, then extracts center frequency and phase information of noise of the low-frequency pulser by fast Fourier transform, and adjusts the excitation and sampling time of the acoustic signal according to the center frequency and phase information of the noise of the low-frequency pulser. Accordingly, the coincidence of the acoustic signal excited by the acoustic instrument and the acoustic signal generated by operation excitation of the pulser can be actively avoided, and the signal-to-noise ratio of the received signal of the acoustic instrument can be effectively improved.

Noise reduction measurement method of acoustic while drilling data based on signal synchronization

A signal acquisition method of an azimuthal electromagnetic wave resistivity instrument includes receiving, by a receiving antenna, a magnetic induction signal after formation attenuation, and converting the received magnetic induction signal into an electrical signal; amplifying, by a preamplifier circuit, a fixed gain of a received signal with nV level amplitude induced on the receiving antenna; controlling a filtering circuit to filter the amplified signal; amplifying the filtered signal using a programmable amplifier circuit to generate a target signal; and conducting digital conversion for the target signal that meets the requirements of low-frequency acquisition.

Signal acquisition method and device of azimuthal electromagnetic wave resistivity instrument while drilling

The present disclosure provides a method and device for synchronizing azimuth detection data while drilling. The method includes: starting, by a control module, according to a command that measurement has been started sent by a tool face angle measurement module, a timer to record a first time, and sending, by the control module, a detection signal acquisition starting command to a detection signal acquisition module; performing, by the detection signal acquisition module, a parameter configuration according to the detection signal acquisition starting command, and sending, by the detection signal acquisition module, a command that work has been started to the control module based on a configuration completion state; stopping the timer and recording a second time by the control module according to the command that work has been started.

Method for synchronizing azimuth detection data while drilling and device for azimuth detection while drilling

The present invention belongs to the field of geological exploration and specifically relates to the fault characterization method and system for precise navigation of deep oil and gas based on image fusion, aiming to solve the problem that faults in deep formations are difficult to characterize with conventional seismic interpretation methods. The present invention includes: obtaining amplitude gradient images by calculating amplitude gradient vectors; calculating dip attribute images based on the enhanced seismic data; fusing gradient amplitude attribute fault confidence region with dip angle attribute data volume that defines the fault position through a hierarchical wavelet transform method to obtain a superimposed fault attribute map; dividing bead-like structures based on superimposed fault attribute maps; calculating the score of branch fault data points based on the center point position of bead-like structures, and dividing and analyzing the dominant fault areas.

Fault characterization method and system for precise navigation of deep oil and gas based on image fusion

The present invention provides a processing method and device for data of a well site test based on a knowledge graph. The processing method for the data of the well site test based on the knowledge graph comprises: carrying out format identification on received historical data of the well site test to generate format identification results; establishing a mind map according to the format identification results; generating the knowledge graph of the data of the well site test according to the mind map; and processing the historical data of the well site test and new data of the well site test according to the knowledge graph.

Processing method and device for data of well site test based on knowledge graph

The present invention belongs to the field of treatment for data identification and recording carriers, and specifically relates to a method and system for analyzing filling for a karst reservoir based on spectrum decomposition and machine learning, which aims to solve the problems that by adopting the existing petroleum exploration technology, the reservoir with fast lateral change cannot be predicted, and the development characteristics of a carbonate cave type reservoir in a large-scale complex basin cannot be identified. The method comprises: acquiring data of standardized logging curves; obtaining a high-precision 3D seismic amplitude data body by mixed-phase wavelet estimation and maximum posteriori deconvolution and enhancing diffusion filtering. According to the method and the system, the effect of identifying the development characteristics of the carbonate karst cave type reservoir in the large-scale complex basin can be achieved, and the characterization precision is improved.

Method and system for analyzing filling for karst reservoir based on spectrum decomposition and machine learning

The present invention belongs to the field of treatment for data identification and recording carriers, and specifically relates to a method and system for evaluating the filling characteristics of a deep paleokarst reservoir through well-to-seismic integration, which aims to solve the problems that by adopting the existing petroleum exploration technology, the reservoir with fast lateral change cannot be predicted, and the development characteristics of a carbonate cave type reservoir in a large-scale complex basin cannot be identified. The method comprises: acquiring data of standardized logging curves; obtaining a high-precision 3D seismic amplitude data body by mixed-phase wavelet estimation and maximum posteriori deconvolution and enhancing diffusion filtering. According to the method and the system, the effect of identifying the development characteristics of the carbonate karst cave type reservoir in the large-scale complex basin can be achieved, and the characterization precision is improved.

Method and system for evaluating filling characteristics of deep paleokarst reservoir through well-to-seismic integration

The present invention discloses a device for performing temperature correction on an induction logging tool and deep stratum environmental simulation, including: a box body, configured to accommodate the induction logging tool and a deep stratum environmental simulation system; an air channel, configured to make heated air fill the box body; a circulating fan, configured to make the heated air enter the air channel; an electric heater, configured to heat air; a temperature controller, configured to control power of the electric heater; the deep stratum environmental simulation system, configured to simulate lithological and fluid situations in different stratum environments; a data collection system, configured to collect, store, process, and display a signal in real time; and a control unit, configured to control operation of the entire device. The device for performing temperature correction on an induction logging tool and deep stratum environmental simulation provided in the embodiments of the present invention can accurately simulate a complex environment of a deep stratum, thereby increasing measurement precision.

Device for performing temperature correction on induction logging tool and deep stratum environmental simulation

The present disclosure provides an earthquake evaluation method based on multi-type geophysical data. The method includes: acquiring natural seismic data about intraplate earthquakes that had occurred, surface elevation data, Bouguer gravity anomaly data, aeromagnetic anomaly data, seismic wave tomography, crustal GPS movement rate and focal mechanism solution in a target region; constructing planar grids of the target region, and respectively performing plane gridding processing on the natural seismic data about the intraplate earthquakes that had occurred, the surface elevation data, the Bouguer gravity anomaly data, and the aeromagnetic anomaly data based on the constructed planar grids of the target region; determining a plane distribution map of a meizoseismal area in the target region based on the data subjected to the plane gridding processing; and superimposing a surface elevation map and the plane distribution map of the meizoseismal area in the target region with the seismic wave tomography, and analyzing the crustal movement on both sides of the meizoseismal area and the matching relationship between the meizoseismal area and the crustal geological structure in combination with the crustal GPS movement rate and the focal mechanism solution so as to determine the geologic origin of a pleistoseismic zone.

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Beijing, China

Wenxiu Zhang