186 results about "Geosteering" patented technology

This invention is directed to a downhole method and apparatus for simultaneously determining the horizontal resistivity, vertical resistivity, and relative dip angle for anisotropic earth formations. The present invention accomplishes this objective by using an antenna configuration in which a transmitter antenna and a receiver antenna are oriented in non-parallel planes such that the vertical resistivity and the relative dip angle are decoupled. Preferably, either the transmitter or the receiver is mounted in a conventional orientation in a first plane that is normal to the tool axis, and the other antenna is mounted in a second plane that is not parallel to the first plane. This invention also relates to a method and apparatus for steering a downhole tool during a drilling operation in order to maintain the borehole within a desired earth formation. The steering capability is enabled by computing the difference or the ratio of the phase-based or amplitude-based responses of the receiver antennas which are mounted in planes that are not parallel to the planes of the transmitter antennas. Although this invention is primarily intended for MWD or LWD applications, this invention is also applicable to wireline and possibly other applications.

A novel on-the-fly data processing technique is useful for extracting signals from the azimuthal variation of the directional measurements acquired by a logging tool within a borehole. The relevant boundary, anisotropy and fracture signals are extracted from the formation response through fitting of the azimuthal variation of the measured voltages to some sinusoidal functions. The orientation of the bedding is also obtained as a result. The extracted directional signals are useful for obtaining boundary distances and making geosteering decisions. Two techniques involving inversion and cross-plotting may be employed, depending on the nature of the boundary. A Graphical User Interface (GUI) is part of a system to facilitate flexible definition of inversion objectives, for improving the inversion results, and for visualization of the formation model as well as inversion measurements.

An earth model is formed in real time during drilling of a well by incorporating up-to-the-minute knowledge derived from geology, seismic, drilling, and engineering data. The process of forming the model utilizes Logging-While-Drilling (LWD) or Measuring-While-Drilling (MWD) data directly from the drilling rig as the well is drilled. The LWD or MWD data is sent to visualization centers and compared with other data such as existing geological models, the proposed well plan and present interpretation of the subsurface stratigraphy. The results of the comparison enable experts to analyze anomalous results and update the geological model within minutes of penetration of a formation during drilling. Well drilling efficiency is improved, and an “on-the-spot” road map is provided for maximal reservoir contact and pinpoint accuracy.

A method for geosteering while drilling a formation includes generating a plurality of formation models for the formation, where each of the plurality of the formation models includes a set of parameters and a resistivity tool therein and locations of the resistivity tool differ in the plurality of the formation models. The method may also include computing predicted tool responses for the resistivity tool in the plurality of formation models, acquiring resistivity measurements using the resistivity tool in the formation, and determining an optimum formation model based on a comparison between the actual tool response and the predicted tool responses. The method may also include steering a bottom home assembly based on the optimum formation model.

Method of analyzing a subterranean formation traversed by a wellbore. The method uses a tool comprising a transmitter antenna and a receiver antenna, the subterranean formation comprising one or more formation layers. The tool is suspended inside the wellbore, and one or more electromagnetic fields are induced in the formation. One or more time-dependent transient response signals are detected and analyzed. Electromagnetic anisotropy of at least one of the formation layers is detectable. Geosteering cues may be derived from the time-dependent transient response signals, for continued drilling of the well bore until a hydrocarbon reservoir is reached. The hydrocarbon may then be produced.

Measurements made with a multicomponent logging instrument when used in a substantially horizontal borehole in earth formations are diagnostic of the direction of beds relative to the position of the borehole. When the logging instrument is conveyed on a drilling assembly, the drilling trajectory may be maintained to follow a predetermined trajectory or to maintain a desired distance from a boundary such as an oil-water contact.

A three-coil bucking system is used for determination of a formation resistivity property ahead of the drill bit. The conductive drill pipe is provided with non-conductive inserts in the proximity of at least one transmitter and at least two receivers. Transient electromagnetic signals are processed to give the estimate of the resistivity property and for geosteering.

A transverse induction transmitter on an instrument induces currents in an earth formation when it is pulsed. Transient measurements made at transverse and axial receivers are used for determination of a distance to a bed boundary. This may be used to control the drilling direction. Alternatively, a transmitter on an instrument having a conductive body induces currents in the earth formation. Transient signals are measured and the effect of the conductive body is removed by using a reference signal measured in a homogenous space.

In some embodiments, an apparatus and a system, as well as a method and an article, may operate to acquire input data to determine properties of a formation, using a combination of down hole transmitters and receivers, to select a portion of the input data using a formation model chosen from a plurality of down hole tool response models in a formation model database, based on a valid sensitive range for the bed boundary distance and a greatest signal-to-noise ratio (SNR), and to solve for at least resistivity formation parameters in the properties using the chosen formation model and the selected portion of the input data. The database may be updated with boundary distance and the resistivity formation parameters. Additional apparatus, systems, and methods are disclosed.

The invention relates to a double induction unit resistance meter that includes drill collar, V shaped groove, emitting unit, coupling unit, receiving unit, emitting circuit module, receive controlling circuit module, high pressure sealing cover board, upper sliding circle connector, down sliding circle connector, and wire hole. It could test two ground unit resistance and the emitting coil and the receiving coil are independent. It could test the ground unit resistance real time in drilling process, and could explain the ground invade situation and calculate ground water saturation, distinguish the lithology of the layer location and the hydro-alteration feature. It is suitable to take ground guides in well drilling projects.

The invention discloses a geosteering method for landing a horizontal well and relates to the technical field of well-drilling exploration and development of petroleum and natural gas, in particular relates to a geosteering method for landing a horizontal well after the sloping section is completed in the horizontal well drilling process. The geosteering method is characterized in that the target formation is exploited at a stable angle of inclination along the well trajectory with a certain deviation angle after the sloping section is completed before landing; when the on-site real-time data indicate that the target formation is reached, the target formation is drilled with an increasing angle of inclination until the well trajectory is parallel to the formation dip; and when the sand rock of the target formation is in the optimum display position, the target formation is drilled with a stable angle of inclination. Based on the on-site actual drilling data of the target well and the comprehensive consideration of two possibilities of vertical depth in advance and vertical depth delay of the target formation, the waste of horizontal sections is effectively reduced and the well trajectory is effectively protected from drilling through the target formation.

The invention relates to a fast and fine geological orientation method for a shale gas horizontal well. Materials are collected, an orientation comparing standard well and a reference well are determined, and an orientation sign layer and a target spot predicting scheme are determined; a well zone two-dimensional geological orientation model and a well zone three-dimensional geological orientation model are built and regulated, and a two-dimensional vertical section and the three-dimensional geological orientation model of a well to be oriented are amended in time; by means of the characteristics of lithological characters, well deflection, while-drilling gamma and the like of the well to be oriented, the standard well and the reference well, stratum comparing is conducted; the position where a drill is located is judged through three figures, one table and the like; whether the position where the drill is located is in a high-quality shale gas layer section or not is evaluated while drilling; whether an initial geological model is applicable or not is judged; through an equal-thickness comparing method a target spot A is determined and regulated, a target spot B is predicted, and a track of a borehole in a horizontal section is controlled; and the pass-through rate of a high-quality shale gas layer is calculated according to the statistic drilling-meeting thicknesses of a shale reservoir and a high-quality shale reservoir, whether the track is controlled to reach the target spot B or not is judged, and the fast geological orientation effect is evaluated. Fast orientation is achieved, the application range is wide, and application and popularization are easy.

The invention discloses a shale gas horizontal well geosteering method. The method includes following steps: according to lithological and electric characteristics of a target stratum, performing stratigraphic division on the target stratum, and determining and contrasting a marker stratum; on the basis of three-dimensional after-stack time migration and pre-stack time migration data, utilizing a Geoframe interpretation system for human-computer interactive interpretation in a workstation, and performing precise tracking contrast on the target stratum to realize morphological structure of each stratum; adjusting A target track; geosteering a horizontal section, wherein in the process of real drilling of the horizontal section, stratum inclination angle along a track direction usually changes, while drilling data need to be collected timely, a gas stratum and the marker stratum to determine current real drilling position, track needs to be monitored in real time, prediction needs to be performed in advance, and directional construction needs to be guided to ensure the drilling track to pass within a designed stratum range. The shale gas horizontal well geosteering method is simple to operate, easy to master and needless of special professional instrument and equipment.