Remote Geosteering services:
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 (maximizing drilling efficiency), best placement for completion (targeting beds that support best fracking efficiency) and ultimately improving production of individual wells and of a resource play as a whole.
The large majority of our geosteering geologists are former wellsite geologists, thoroughly familiar with all rig operation and comfortable with the constant communication and flow of information needed for this type of work.
Geosteering geologists focus on multiple aspects of the drilling process:
- Continuous supervision of drilling operations;
- Continuous assessment of the stratigraphic location of the drill bit in real time;
- Correlation of drilling, MWD/LWD and mud gas parameters throughout the wellbore and against offsetting wells profiles;
- Use offset well information to optimally land the build section, by utilizing TVD logs with cross plot of offset data;
- Continuous monitoring and critical evaluation of the wellpath inclination and azimuth in relation to stratigraphic markers and porosity windows;
- Continuous communication with directional driller, proactive wellpath adjustments to ensure wellbore placement remains within the acceptable stratigraphic window;
- Proactively evaluating wellpath position in relation to existing and planned wellbores;
- Reservoir navigation
- based on MWD/LWD parameters
- based on gas ratios
- based on proximity data (ranging)
Navigating the reservoir is most often done by correlating MWD or LWD curves recorded over the lateral section with log profiles from control wells (stratigraphic wells or pilot holes). By overlaying curves on a TVD scale, geosteering geologists pinpoint the location of the drill bit in the structure, and can point the wellbore to the desired target within the reservoir with extreme accuracy.
Real-time data relay from the wellsite is a day to day reality and has become very robust and reliable in the past few years. Geosteering geologists acquire continuous drilling and MWD parameters to decide the optimal steering direction in real time at any distance. Decisions are instantly relayed to directional drillers. Employing geologists with extensive wellsite experience is a key factor for a efficient remote procedure system.
Cuttings samples are collected at the wellsite using semi-automated sample catching systems that require minimal supervision; they can be prepared and described at a later time in a laboratory environment. For in-depth analyses, critical samples can be collected and preserved in geo-jars and gas samples can be harvested in iso-tubes and preserved for subsequent analyses. Petrographic studies can be subsequently performed on collected drill cuttings samples.
Directional Drilling supervision
Assessing the trajectory of the wellpath is the single most important aspect of geosteering. This is done by following established procedures and protocols:
- Plotting actual well path against designed well trajectory
- Identification of wellpath relative to stratigraphic markers (wellpath with TVD gamma and formation tops)
- Constant communication with directional drillers to ensure wellpath follows optimal trajectory
- best reservoir or
- best wellbore placement or
- optimal drill path
- MWD/LWD supervision: data stream monitoring
In many respects, geosteering is the opposite of 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, to pick optimal drilling windows or to establish optimal placement of fracking stages.
- Utilizing multiple curves to pinpoint the structural position of the wellpath;
- 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;
- Exporting detailed structure data, with accuracy and data steps far exceeding seismic interpretation or traditional geomodels.
Other aspects of the drilling process are observed and can be optimized using geosteering procedures:
- Assess hole condition by monitoring drilling parameters and mud properties, paying particular attention to any indications of overpressure zones, sticky hole or lost circulation;
- Establish estimated timelines for events such as encountering critical formation tops, casing points, entering reservoir, and reaching total depth;
- Estimate how long current bit is expected to drill, and when the next trip is expected;
- Generate detailed daily reports (striplogs, operations reports, data files), to be distributed within the company and to partners as needed;
- Generate exhaustive final reports and striplogs (striplogs, final geological report, data files, etc);
- Provide integration with geomodeling in real time.
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