95 results about "Resistivity logging" patented technology

The invention provides a reservoir physical property parameter pre-stack seismic inversion method based on resistivity logging constraint. The method comprises the following steps: cutting observation data and depth; normalizing the seismic data, the resistivity data and the travel time to form network input; constructing a neural network framework, substituting the obtained porosity and saturation into an elastic rock physical model, and calculating to obtain an elastic parameter; the elastic parameters are substituted into a zoeppritz equation, and an underground reflection coefficient is obtained through calculation; generating a Ricker wavelet, and performing convolution calculation on the Ricker wavelet and the reflection coefficient to obtain predicted pre-stack seismic data; the porosity and the saturation are substituted into an Archie formula, and the predicted resistivity is obtained through calculation; constructing a target function; automatic differentiation is carried out, network parameters are updated, and then network output porosity and saturation are optimized. Reservoir parameter inversion driven by physical information is realized, and an intelligent scheme is provided for reservoir parameter prediction and evaluation in oil-gas exploration and development.

The invention relates to the technical field of logging while drilling, and particularly provides a logging while drilling electromagnetic wave resistivity logging inversion method. The method comprises the following steps: constructing an XGBoost feature screening module, and optimizing a data set through the XGBoost feature screening module to obtain an optimized data set; according to the method, a BiLSTM-Transformer model is constructed, an optimized data set is input into the model, an inversion result is obtained, the inversion precision and the calculation efficiency are improved, and inversion of the target stratum resistivity, the adjacent layer surrounding rock resistivity and the boundary distance under the anisotropic stratum model is achieved.

This invention discloses a method and related apparatus for calculating the skin factor of oil and gas wells based on resistivity logging. The method includes: acquiring resistivity logging data and well test skin factor data of the target formation in an oil and gas field; establishing a skin factor calculation model based on the resistivity logging data and well test skin factor data; and calculating the skin factor of the well to be logged in the oil and gas field based on the skin factor calculation model. This invention utilizes resistivity logging data and well test skin factor data of the target formation in an oil and gas field to establish a skin factor calculation model, and calculates the skin factor of the well to be logged in the oil and gas field based on this model. This provides more accurate production capacity prediction for the oil and gas field production and development field, and avoids the determination of various process parameters and the calculation process of complex skin factor models, effectively solving the problem of difficulty in determining the skin factor in actual production and development.

Example methods and systems for wellbore fluid saturation mapping are disclosed. One example method includes obtaining, from a resistivity logging tool and during a process of drilling a wellbore in a reservoir formation, resistivity data of the reservoir formation in a first multiple azimuthal directions. Fluid saturation of the reservoir formation in the first multiple azimuthal directions is determined based on the resistivity data. A three-dimensional (3D) model of fluid saturation around the wellbore is determined based on the fluid saturation of the reservoir formation in the first multiple azimuthal directions. One or more steering commands for steering a drill bit during the process of drilling the wellbore is generated based on the 3D model of fluid saturation around the wellbore. A downhole drilling assembly is steered during the process of drilling the wellbore, based on the one or more steering commands.

The invention discloses a split resistivity logging button electrode, a preparation method and an instrument, the split resistivity logging button electrode comprises an upper shell, an electrode block, a probe, an insulation assembly, a metal base and a bottom plate, the electrode block is in sealed connection with an upper opening of the upper shell, the electrode block comprises a plurality of electrode assemblies which are not in contact with each other, the metal base is provided with a plurality of probe holes, and the probe holes are communicated with the bottom plate. The electrode assembly is provided with a probe connecting hole, the top end of the probe penetrates through the probe hole and is connected with the electrode block through the probe connecting hole, the bottom end of the probe is provided with a bonding wire hole, the bottom plate is connected to a lower opening of the upper shell in a sealed mode, and a wire is led out of the bonding wire hole and then connected with an instrument through a wire passing hole of the bottom plate. The insulation assemblies enable insulation layers with certain insulation thickness to be formed between the electrode assemblies and between the electrode assemblies and the metal base, the space between the electrode assemblies is filled with the insulation layers in a sealed mode, the upper shell is connected with an instrument in a sealed mode, and the process design and product implementation difficulty is lowered while the performance is not affected.

The invention belongs to the technical field of petroleum and natural gas drilling, and discloses a near-bit gamma electromagnetic wave imaging logging instrument with far detection emission and power generation functions, which comprises a drill collar body, a water hole is arranged in the drill collar body along the axial direction, and an emission antenna, a first receiving antenna, a second receiving antenna, a first antenna port and a second antenna port are arranged on the drill collar body; a sealing fastening sleeve, a circuit framework, a lower fluid director and a mud turbine power generation device are arranged in the water hole, the circuit framework is provided with a containing cavity, the middle of the mud turbine power generation device is located in the containing cavity, the lower end of the mud turbine power generation device is connected with the lower fluid director, and an orientation gamma measuring circuit is arranged in the circuit framework. The near-bit lateral resistivity logging instrument has a certain forward probing capability and a certain azimuth electromagnetic wave measuring function, and has larger axial forward probing and radial probing edge distance compared with a near-bit lateral resistivity logging instrument. The method is suitable for oil-based mud and is also suitable for water-based mud.

The invention relates to the technical field of equipment detection, and discloses an equipment measurement and detection method, system and equipment, and the method comprises the steps: utilizing logging equipment to synchronously measure a first resistivity measurement value, a second resistivity measurement value and a third resistivity measurement value of different depths of an underground stratum; calculating a well fluid invasion depth value according to the first resistivity measurement value, the second resistivity measurement value and the third resistivity measurement value; solving a real formation resistivity value based on the well fluid invasion depth value; and performing gradient distortion correction on the real formation resistivity value according to the well fluid conductivity and the formation water conductivity to obtain a formation resistivity detection result. According to the method, the accuracy, adaptability and reliability of well fluid invasion correction of the resistivity logging equipment are improved.

The invention discloses a tight reservoir stoneley wave hydrocarbon reservoir identification method, a tight reservoir stoneley wave hydrocarbon reservoir identification system and a medium. The tight reservoir stoneley wave hydrocarbon reservoir identification method comprises the following steps: S1, comprehensively dividing a reservoir and a dry layer by utilizing one or more of well logging information, well wall coring, rock debris logging and gas logging; s2, taking the stoneley wave logging curve as a main curve and the transverse wave as an auxiliary curve in the same logging channel, selecting a proper scale, determining the overlapping relationship between the stoneley wave and the transverse wave of the reservoir section and the size of an overlapping region, and calculating the size of the overlapping region, namely a fluid movement index; s3, establishing interpretation standards of an oil-gas layer, an oil-water layer and a dry layer by utilizing the fluid movement index and oil testing and production testing data; and S4, comprehensively identifying an oil-gas layer, an oil-water layer and a dry layer by utilizing the fluid movement index and the interpretation standard in the step S2. The method solves the problem that the tight reservoir resistivity logging cannot effectively identify the hydrocarbon reservoir.

The invention discloses a shale reservoir capacity analysis method and device, and relates to the technical field of shale gas geological exploration, and the method comprises the steps: obtaining the logging data and ground temperature data of a shale reservoir; the logging data comprises mineral element logging data, density logging data, total organic carbon content and resistivity logging data of each depth point of the shale reservoir; determining the pore volume index of each depth point of the shale reservoir according to the mineral element logging data and the density logging data; the pore volume index reflects an actual pore volume value of the shale reservoir; according to the ground temperature data, the total organic carbon content and the resistivity logging data, the specific surface area index of each depth point of the shale reservoir is determined; the specific surface area index reflects the actual value of the specific surface area of the shale reservoir; and determining a shale reservoir capacity analysis result according to the pore volume index and the specific surface area index. The shale reservoir capacity analysis accuracy can be improved.

The invention relates to the technical field of open hole well logging in petroleum and natural gas exploration and development, in particular to an ultra-thin layer resistivity logging variable K value interpretation method and device, equipment and a medium. The method comprises the steps that stratum parameters are set, forward modeling is carried out to measure five parameters, the theoretical K value and the Rd4-Rs18 value of each layer are calculated according to the five parameters, and the Rd4-Rs18 value of each layer is calculated according to the theoretical K value and the Rd4-Rs18 value; the neural network is trained through set parameters and measurement and calculation parameters, an interpretation model is obtained, resistivity and invasion influence correction is carried out on the variable K value, and three stratum parameters of the variable K value of each layer, the specific value of the stratum and the resistivity of the invasion zone and the radius of the invasion zone can be explained through the interpretation model; the error between the variable K value and the theoretical K value is the quantitative interpretation error of the true resistivity of the stratum; the method is used for solving the problem that the stratum true resistivity value cannot be quantitatively explained due to the fact that the resistivity of the corresponding layer thickness cannot be developed and an invasion influence correction chart cannot be developed due to the fact that the obtained apparent resistivity value of the ultrathin layer is too low and the change range is too small by an original fixed K value explaining method.

The invention discloses a formation pore pressure calculation method, system, equipment and medium, and the method comprises the steps: marking collected lithologic sections and geological stratification, and selecting at least one of collected seismic horizon velocity, density logging, acoustic logging and resistivity logging as sensitive parameters to establish a normal compaction trend line of a middle-shallow normal pressure section; a correction coefficient is adjusted by using the collected pressure measurement data, and finally, a traditional Eaton method formula is improved by using the adjusted correction coefficient, and a new formation pore pressure calculation formula is established; according to the method, the normal compaction trend line is fully utilized, the distortion of the normal compaction stratum is effectively inhibited while the abnormal pressure change is highlighted, the stability is better, the distortion is less, the pressure trend of the overlying stratum does not need to be calculated, parameters are few, the calculation efficiency is high, calculation can be carried out without logging data, the application range is wider, and the method is particularly suitable for low exploration areas without wells and with few wells.

The invention relates to the technical field of logging while drilling, and discloses a stratum simulation box for a lateral resistivity logging while drilling tool and a design method of the stratum simulation box. The design method comprises the following steps: determining an electrode structure of an azimuth electrode system of the lateral resistivity logging-while-drilling tool; determining a resistance network of the stratum simulation box based on an electrode structure and a working principle of the azimuth electrode system; according to the resistance network of the stratum simulation box and a working principle, determining a calculation scheme of each resistance parameter in the resistance network of the stratum simulation box; and determining each resistance value of the stratum simulation box resistance network under the typical stratum condition by utilizing a three-dimensional finite element program. The formation simulation box for the while-drilling lateral resistivity logging instrument is designed and generated through the method, various formations simulated by the formation simulation box can be measured by the while-drilling lateral resistivity logging instrument indoors, the working state of the instrument can be checked conveniently, and the instrument can be debugged, maintained and calibrated conveniently; and the time for repeatedly testing and verifying the performance of the instrument is greatly saved.

The application discloses a high-resistivity formation borehole correction method based on high-frequency electromagnetic wave resistivity logging, which comprises the following steps: s1, establishing a high-resistivity formation electromagnetic wave resistivity logging method; s2, developing a magnetic dipole source electromagnetic field pseudo-analytical fast algorithm based on different borehole columnar layered formation models in the high-resistivity formation; s3, simulating and analyzing the problem of formation resistivity anomaly caused by the existence of the borehole; s4, selecting different borehole factor parameters under the high-resistivity formation condition, and determining the data range contained in the borehole correction database; s5, carrying out forward simulation and analysis on the borehole influencing factors such as mud resistivity, hole diameter, eccentricity and relative dielectric constant; s6, detailing the change rule of the response results of different influencing factors in the high-resistivity formation; and s7, combining the data obtained from the simulation results and establishing a borehole correction database, thereby forming the high-resistivity formation borehole correction method based on the high-frequency electromagnetic wave resistivity logging.

This invention discloses a method and device for correcting eccentric wellbore in resistivity logging of ultra-deep fractured reservoirs. The method involves continuously moving a conventional dual-lateral logging tool downhole while simultaneously acquiring shallow and deep resistivity information of the reservoir, obtaining continuous shallow and deep resistivity response curves at different reservoir depths. Combining wellbore size and mud resistivity curves with a pre-established dual-lateral shallow and deep resistivity eccentric wellbore correction chart, the eccentric wellbore correction chart is discretized and digitized into an eccentric wellbore database. Based on the shallow and deep resistivity data at different depths, a resistivity eccentric wellbore correction algorithm is used to correct the actually measured dual-lateral shallow and deep resistivity data, obtaining shallow and deep resistivity curves that eliminate the influence of wellbore size, mud resistivity, and instrument eccentricity. This provides logging data interpreters with more realistic dual-lateral resistivity curve data reflecting the characteristics of fractures in ultra-deep reservoirs, ensuring the effective evaluation of fracture characteristics in ultra-deep reservoirs.

The invention relates to a method for establishing an identification chart of an oil-water dry layer and an interpretation method of the oil-water dry layer, and belongs to the technical field of oil and gas field exploration and development. The method for establishing the identification chart comprises the following steps of: i) acquiring resistivity logging values, interval transit time logging values, density logging values and oil-bearing level values of standard oil layers, standard water layers and standard dry layers of all wells put into production verification in a research area, and respectively calculating K1 values and K2 values of the standard oil layers, the standard water layers and the standard dry layers of all the wells by utilizing a formula I and a formula II; and ii) establishing an oil-water dry layer identification chart based on the K1 and K2 values of the standard oil layer, the standard water layer and the standard dry layer of each well calculated in the step i). According to the method for establishing the identification plate, the difference between the relative values (K1 and K2) of different reconstructed reservoirs is more obvious, so that the oil-water layer identification plate established according to the method is higher in distinction degree and clearer in range boundary.

The application discloses a bedding anisotropy stratum large-inclination well and horizontal well resistivity correction method, which comprises the following steps: (1) selecting several discrete well inclination data and corresponding resistivity logging response values in the same set of bedding anisotropy stratum according to stratum layering data, well inclination data and resistivity logging data; (2) fitting the selected data set according to a given correction model to determine r0, r 90 and the value of B; (3) combining the well inclination data to calculate the correction coefficient alpha (theta) of the target layer at different measuring depths; (4) according to the definition of the correction coefficient, the correction model of the resistivity curve is derived; (5) according to the correction model, the resistivity of the bedding anisotropy stratum large-inclination well and horizontal well is corrected. The method can correct the resistivity logging data, can get rid of the dependence on rock physical experiments, has low error rate, is simple and convenient to operate, and saves the cost of downhole sample coring and rock physical experiment.

This invention relates to the field of oil and gas field exploration and development, and discloses a logging identification method, system, equipment, and medium for hydrogen-rich reservoirs in clastic rocks. The method includes: identifying oil and gas reservoirs in clastic rock reservoirs based on differences in the conductivity of fluids within the reservoirs; identifying gas reservoirs in clastic rock reservoirs based on differences in the influence of oil and gas on the formation's elastic modulus; and identifying hydrogen-rich reservoirs based on differences in gas density within the gas reservoirs combined with differences in the gas's occurrence environment. The technical solution of this invention comprehensively utilizes logging methods such as shallow and deep resistivity logging, density logging, neutron logging, sonic logging, and natural gamma ray spectroscopy logging to identify hydrogen-rich reservoirs in clastic rock reservoirs, thereby improving the effectiveness and accuracy of hydrogen-rich reservoir identification.

The invention relates to the technical field of geophysical detection, and discloses a geological drilling physical detection device which comprises a resistivity logging instrument main machine, a box cover, a control panel and a display screen, the box cover, the control panel and the display screen are connected to the resistivity logging instrument main machine, a rainproof film is fixedly connected to one side of the box cover, and two symmetrically-arranged fixing plates are fixedly connected to the bottom end of the rainproof film; a plurality of connecting magnetic blocks are fixedly connected into each fixing plate, a plurality of fixing magnetic blocks corresponding to the connecting magnetic blocks in position are fixedly connected to the surface of the resistivity logging instrument host, a rain curtain is fixedly connected to the bottom of the rainproof film, a back film is fixedly connected between the bottoms of the inner sides of the rainproof film, and a wire arrangement groove is formed in the surface of the back film. The middle of the rainproof film is fixedly connected with an observation plate. According to the geological drilling physical detection device, through the multi-layer flexible protective cover formed by the rainproof film, the rain shielding curtain and the back film, cable interfaces and surface gaps of the host can be covered in all directions, and it is ensured that the device can still work normally under the severe weather condition.

The application discloses a method and system for identifying single sand body combination relationship of meandering river reservoirs, comprising: obtaining the correlation between the length of the well track section corresponding to each resistivity change state on the resistivity logging curve in the horizontal well drilling process and the apparent dip angle of the sand-shale interface corresponding to the corresponding well track section; based on the correlation, determining the apparent dip angle of the corresponding sand-shale interface by using the length of the well track section corresponding to each resistivity change state on the resistivity logging curve of the target single sand body combination, thereby obtaining the distribution characteristics of the sand-shale interface in the target single sand body combination; by using the numerical distribution characteristics and the curve section shape corresponding to each resistivity change state on the resistivity logging curve of the target single sand body combination, combining the distribution characteristics of the sand-shale interface, obtaining the geological structure change along the drilling direction in the target single sand body combination, thereby forming the identification result of the target single sand body combination relationship. The application realizes accurate identification of the underground single sand body combination relationship.

The present invention discloses a split resistivity logging button electrode, a preparation method and an instrument, comprising: an upper housing, an electrode block, a probe, an insulating component, a metal base and a bottom plate. The electrode block is hermetically connected to the upper opening of the upper housing. The electrode block includes a plurality of non-contact electrode components. A plurality of probe holes are formed on the metal base, and probe connection holes are formed on the electrode components. The top end of the probe passes through the probe holes and is connected to the electrode block through the probe connection holes. A wire welding hole is formed at the bottom end of the probe. The bottom plate is hermetically connected to the lower opening of the upper housing. The wire is led out through the wire welding hole and connected to the instrument through the wire passing hole of the bottom plate. The insulating component forms an insulating layer with a certain insulating thickness between each electrode component and between the electrode component and the metal base. Each electrode component is hermetically filled with the insulating layer. The upper housing is hermetically connected to the instrument. The present invention reduces the difficulty of process design and product implementation while not affecting the performance.

Methods and systems are disclosed. The methods may include obtaining rock core data from a formation, obtaining well logs, which include a current resistivity log, from a well within the formation, and inputting the well logs into a trained machine learning (ML) model. The method further includes producing a predicted permeability log from the trained ML model, determining a rock type log based on the rock core data, and determining an initial saturation log based on the rock type log. The method still further includes predicting, using an Archie-type model, an initial resistivity log based on the initial saturation log, identifying at least one of a water encroachment zone and a pay zone along the well by comparing the initial resistivity log and the current resistivity log, and designing a completion plan for the well based on the at least one of the water encroachment zone and the pay zone.

The present invention provides a method for estimating hydrocarbon saturation of a hydrocarbon-bearing rock from a measurement for an electrical property a resistivity log and a rock image. The image is segmented to represent either a pore space or solid material in the rock. An image porosity is estimated from the segmented image, and a corrected porosity is determined to account for the sub-resolution porosity missing in the image of the rock. A corrected saturation exponent of the rock is determined from the image porosity and the corrected porosity and is used to estimate the hydrocarbon saturation. A backpropagation-enabled trained model can be used to segment the image. A backpropagation-enabled method can be used to estimate the hydrocarbon saturation using an image selected from a series of 2D projection images, 3D reconstructed images and combinations thereof.

This invention discloses an integrated logging-while-drilling (LOD) and measurement drill string assembly, relating to the field of oil and gas drilling engineering technology. It provides a series connection scheme for core protective drill string components, offering two switchable configurations: one with a mud motor and one without. Both configurations consist of an azimuth density neutron logging sub, a bidirectional communication power supply sub, an acoustic logging sub, a resistivity logging sub, an upper connecting sub, a flexible sub, a lower connecting sub, an azimuth gamma logging sub, and a steering actuator connected in series according to a fixed logic. The configuration with a mud motor only requires adding a mud motor at a designated location to complete the structural switch, without changing the series connection of the remaining subs. This assembly scheme is applicable to various drilling scenarios such as offshore exploration and development, deepwater drilling, complex directional wells, highly deviated wells, and horizontal wells. It enables integrated operations of geological steering, formation evaluation, and wellbore stability analysis during drilling, effectively improving drilling efficiency and reducing operational risks.

The invention provides a while-drilling electromagnetic wave resistivity logging inversion method based on a quasi-Newton method, and relates to the technical field of oil-gas exploration and development, and the method comprises the steps: collecting the actual measurement response data of an isotropic or anisotropic target stratum, constructing a three-layer TI medium stratum model, and determining the to-be-inverted parameters; performing global optimization by adopting a genetic algorithm, and outputting an optimal result as an initial value; constructing a quasi-Newton inversion model containing a regularization term, dynamically updating a Jacobian matrix by using a Broyden updating rule, introducing a diagonal adaptive damping matrix to replace a fixed damping factor, and adaptively adjusting the damping strength according to a parameter relative increment ratio; and inputting the initial value into the improved model for iterative operation until a termination condition is met. The method gets rid of manual experience dependence, avoids local extremum convergence, improves the inversion precision, reduces the number of iterations, improves the calculation efficiency, accurately inverts key parameters, meets the requirements of real-time geosteering engineering, and improves the oil-gas exploration and development efficiency.

The invention belongs to the technical field of logging while drilling, and provides a full-component minimum symmetry compensation antenna system and a logging while drilling electromagnetic wave resistivity logging method.The full-component minimum symmetry compensation antenna system comprises a drill collar body, a first transmitting antenna, a second transmitting antenna, a first receiving antenna, a second receiving antenna, a third receiving antenna and a fourth receiving antenna; the first transmitting antenna and the second transmitting antenna are obliquely orthogonal in space, and magnetic moment vectors are respectively arranged on an XZ plane and a YZ plane and form a first inclination angle with a Z axis; the first receiving antenna, the second receiving antenna, the third receiving antenna and the fourth receiving antenna are arranged in a mirror image mode along the midpoint of the first transmitting antenna and the midpoint of the second transmitting antenna, and magnetic moment vectors of the first receiving antenna and the fourth receiving antenna are arranged on the XZ plane and form a second inclination angle and a negative second inclination angle with the Z axis respectively. And the magnetic moment vectors of the second receiving antenna and the third receiving antenna are arranged on the YZ plane and respectively form a second inclination angle and a negative second inclination angle with the Z axis.

The application discloses a kind of resistivity logging automatic gain control circuit, comprising: transconductance amplifier circuit, signal conditioning circuit, integration circuit, the transconductance amplifier circuit includes: transconductance amplifier, resistance R1, resistance R2, resistance R3, the one end of resistance R1 is connected with the noninverting terminal of transconductance amplifier, the other end of resistance R1 is grounded, the one end of resistance R2 is connected with the inverting terminal of transconductance amplifier, the other end of resistance R2 is grounded, the one end of resistance R3 is connected with the inverting terminal of transconductance amplifier, the other end of resistance R3 is connected with the output terminal of transconductance amplifier, output voltage V2 is input into signal conditioning circuit, and the signal of control foot CON is given by integration circuit.The resistivity logging automatic gain control circuit of the application, this control circuit can automatically adjust amplification according to the amplitude of input signal, also has the characteristics of strong anti-interference ability, good stability, easy debugging, etc., is suitable for the characteristics of downhole high temperature, complex environment etc.

The present application relates to the technical field of antenna system design verification, and particularly relates to an electromagnetic wave resistivity logging instrument antenna system adjustable ground verification device and method, comprising processing an antenna model, a ruler and a supporting seat; winding a copper wire coil with a preset number of turns on the antenna model and installing a magnetic conductor; fixing the assembled antenna model on the processed ruler according to a preset antenna arrangement scheme; arranging a connecting cable along the ruler; connecting the connecting cable, and performing functional testing and debugging after the connection is completed; the present application adopts 3D printing to quickly manufacture a PLA or non-magnetic material antenna model prototype, and constructs a modular testing system containing flexibly adjustable antenna position and coil turns, realizes parallel verification of a circuit and a mechanical structure, thereby greatly shortening a research and development cycle and significantly reducing material and processing cost waste caused by repeated design.

The utility model relates to a while-drilling comprehensive well logging device which comprises a first well logging mechanism, a second well logging mechanism, a connecting assembly and a drill bit. The first logging mechanism comprises an inclination measuring module and a natural gamma logging module; the second logging mechanism comprises a micro-processing module, a coil assembly and an emission control module, the micro-processing module is connected with the inclinometry module, the natural gamma logging module, the coil assembly and the emission control module, and the coil assembly is connected with the emission control module; the connecting assembly comprises a first connector and a second connector, the two sides of the first connector are connected with the first well logging mechanism and the second well logging mechanism respectively, and one side of the second connector is connected with the second well logging mechanism; the drill bit is connected with the other side of the second connector and used for well drilling. According to the technical scheme, natural gamma logging and electromagnetic wave resistivity logging are integrated, natural gamma lithologic information and electromagnetic wave resistivity lithologic information can be collected at the same time at a time, the multifunctional while-drilling comprehensive logging device is achieved, and the multifunctional while-drilling comprehensive logging device has higher resolution and accuracy compared with lithologic information collected singly in multiple times.

Aspects of the disclosure provide for using anticorrelation in propagation resistivity logs to detect boundary approaching conditions. Geosteering may be performed based on the detected boundary approaching conditions. The boundary detection and geosteering may be for a high angle well. The anticorrelation may be between attenuation resistivity and phase shift resistivity.

Example methods and systems for wellbore fluid saturation mapping are disclosed. One example method includes obtaining, from a resistivity logging tool and during a process of drilling a wellbore in a reservoir formation, resistivity data of the reservoir formation in a first multiple azimuthal directions. Fluid saturation of the reservoir formation in the first multiple azimuthal directions is determined based on the resistivity data. A three-dimensional (3D) model of fluid saturation around the wellbore is determined based on the fluid saturation of the reservoir formation in the first multiple azimuthal directions. One or more steering commands for steering a drill bit during the process of drilling the wellbore is generated based on the 3D model of fluid saturation around the wellbore. A downhole drilling assembly is steered during the process of drilling the wellbore, based on the one or more steering commands.