Remote Geosteering
Remote geosteering can be used to drill horizontal wells in large resource plays tapping reservoirs with monotonous lithology (silt and shale) with good well control and existing in-depth knowledge of reservoir characteristic from previously drilled stratigraphic wells. Examples of such resource plays include the Duvernay, Montney and Horn River/Muskwa. The goal of geosteering is placing the wellbore in optimal position within the reservoir. Optimal position can target ideal drilling targets within the reservoir (maximising drilling efficiency), best placement for completion (targeting beds that support best fracking efficiency) and ultimately improving production of individual wells and of the resource play as a whole.
An additional advantage of geosteering over traditional approaches is the capability of projecting trends and predicting targets ahead of the bit based on stratigraphic position of wellbore and calculated apparent dips along the section. Utilizing modern geosteering software result in a high degree of precision and increased accuracy.
Remote Supervision
Real-time data relay from the wellsite has become increasingly robust and extremely reliable over the last decade. Geosteering geologists acquire continuous drilling and MWD parameters to decide the optimal steering direction in real time, from any distance. Decisions are then instantly relayed to directional drillers. Employing geologists with extensive wellsite experience is a key factor for an efficient remote procedure system, and one of Chinook’s specialties. The vast majority of our geosteering geologists are former wellsite geologists themselves, intimately familiar with all rig operations.
Modern EDR systems provide real time data transmission from rig to remote station through WITSML protocols. As such, geosteering calculations are constantly updated at every survey point, resulting in continuous assessment of wellpath position. Cloud hosted geosteering interpretations allows all stakeholders to monitor progress continuously or on demand as needed.
Directional Drilling Supervision
Assessing the trajectory of the well path is the single most important aspect of geosteering, whether onsite or remote. This is done by following established procedures and protocols including:
- Plotting actual well path against designed well trajectory
- Identification of well path relative to stratigraphic markers (well path with TVD gamma and formation tops)
- Constant communication with directional drillers to ensure well path follows optimal trajectory
- Best reservoir, or
- Best wellbore placement, or
- Optimal drill path
- MWD/LWD supervision, data stream monitoring
Advanced Geosteering
In many respects, geosteering is equivalent to reverse geomodeling. By applying geosteering observations, a detailed model of the reservoir can be created while drilling. Such observations can be used to better understand the geological structure, pick optimal drilling windows or establish optimal placement of fracking stages. Advanced geosteering allows for:
- Utilizing multiple curves to pinpoint the structural position of the well path
- Projecting curves measured in pilot wells along lateral sections of wells being drilled (in real time)
- Identifying placement of frack stages based on well position in structure in order to maximize fracking efficiency
- Correlating apparent dips, trends and interpreted faults across multiple wells on large drill pads and mapping interpretations
- Exporting detailed structure data with accuracy and data steps far exceeding seismic interpretation or traditional geomodels
- Integrating drilling, mudlogging, geochemical, completions and seismic data.
Large scale development projects benefit from the combination of software based correlation with cloud shared massive projects. Projects are shared in real time between stakeholders while statistics and machine learning algorithms optimize well placement, drilling parameters and ongoing development directions.
Reporting
Other aspects of the drilling process are observed and can be optimized using geosteering procedures. These include:
- Assessing hole condition by monitoring drilling parameters and mud properties, paying particular attention to any indications of overpressure zones, sticky hole or lost circulation
- Establishing estimated timelines for events such as encountering critical formation tops, casing points, entering reservoir, and reaching total depth
- Estimating how long current bit is expected to drill and when the next trip is expected
- Generating detailed daily reports (striplogs, operations reports, data files) to be distributed within the company and to partners as needed
- Generating exhaustive final reports (striplogs, final geological report, data files, etc.)
- Providing integration with geomodeling in real time
Continuous communication with multiple disciplines is paramount for a successful geosteering operation. Real-time data flow and rapid interpretation of field data can dramatically increase the efficiency of the drilling operation and ultimately increase production.
