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measurements, GeoSphere reveals measurements, GeoSphere reveals is greater than the seismic resolution, subsurface-bedding and ? uid-contact subsurface-bedding and ? uid-contact seismic data can be re? ned and better details at in excess of 100ft (30m) from details at in excess of 100ft (30m) from understood, especially while looking at the wellbore. GeoSphere can map a reser- the wellbore. GeoSphere can map a reser- some of the features on a seismic scale, voir top, allowing a clear, real-time view voir top, allowing a clear, real-time view Seydoux says.

of the reservoir. With this data, operators of the reservoir. With this data, operators By increasing the con? dence in the can land wells in choice locations and can land wells in choice locations and knowledge of the environment drilled, avoid the loss of lateral exposure or creat- avoid the loss of lateral exposure or creat- the mapping while drilling helps ing sumps. Exposing more of the lateral ing sumps. Exposing more of the lateral increase rate of penetration (ROP), section ultimately shows much more section ultimately shows much more improve wellbore stability and hole detail of the area surrounding a reservoir, detail of the area surrounding a reservoir, quality, and optimize well placement. greatly increasing the level of informa- greatly increasing the level of informa- Seydoux pointed out that “the key is tion available to drilling teams in real- tion available to drilling teams in real- knowing earlier and making the right time, aiding operational decision making time, aiding operational decision making decisions. RMWD also helps the overall processes by resolving the reservoir and processes by resolving the reservoir and drilling operation to allow for a smoother its boundaries. its boundaries. borehole. It provides better dogleg con-

By combining the reservoir map- trol and decreases unwanted corrections ping data with seismic interpretation, ping data with seismic interpretation, in trajectory (going from reactive to pro-

GeoSphere can be used to update seismic GeoSphere can be used to update seismic active mode). By detecting and avoiding models for increased understanding of models for increased understanding of potential problematic formations (shale reservoir geology and accurate predic- reservoir geology and accurate predic- or other), it helps avoid side tracking and tions about formations ahead of the bit. tions about formations ahead of the bit. offers better entry angle control. This

There are three main applications is a reservoir mapping technology that for the GeoSphere service, but there for the GeoSphere service, but there bene? ts both drillers and geologists and can be as many applications as there can be as many applications as there geophysicists.” are geologists and ? elds,” Seydoux are geologists and ? elds,” Seydoux There were many challenges to over- says. The three main applications are: says. The three main applications are: come in developing the MWD service for landing a well can be optimized to landing a well can be optimized to commercial use, as it involved proving reduce the number of pilot wells and reduce the number of pilot wells and the viability and ef? ciency of differ- improve the planning of horizontal improve the planning of horizontal ent technologies. In order to attain well wells; geosteering, with respect to the wells; geosteering, with respect to the placement optimization it was necessary main reservoir features and ? uids con- main reservoir features and ? uids con- to have a more extensive understanding tact; and increased reservoir structure tact; and increased reservoir structure of reservoir characteristics. understanding. understanding. “Four major advances make this new

The three main components of tool an effective technology for reser-

GeoSphere are: a BHA that is tailored GeoSphere are: a BHA that is tailored voir imaging. First, the tool modularity to the application; real time connection to the application; real time connection enables simultaneous radial depths of and data transfer from rig to a client’s and data transfer from rig to a client’s investigation in excess of 30m. Second, a of? ce (otherwise well placement is not of? ce (otherwise well placement is not broad range of measurement frequencies possible); and a well placement team in possible); and a well placement team in accommodate a wide range of formation client’s of? ce to provide mapping of for- client’s of? ce to provide mapping of for- resistivity. Third, the antenna design mation structure in real-time using pow- mation structure in real-time using pow- offers a full directional access to the erful computational clusters around the erful computational clusters around the resistivity tensor acquired at each spac- world. To make best use of the service, world. To make best use of the service, ing and frequency. Finally, a powerful it is important to have a fully engaged it is important to have a fully engaged real-time inversion method exploits the client team (geology and geophysics and client team (geology and geophysics and richness of the measurements and their drilling), Seydoux says. drilling), Seydoux says. deep depth of investigation, providing “The mapping-while-drilling service unparalleled support for the interpreta- has many advantages over logging- has many advantages over logging- tion of complex reservoir structures,” while-drilling as LWD tools provide while-drilling as LWD tools provide Seydoux says.

formation evaluation (FE) information in formation evaluation (FE) information in The individual transmitters and a very shallow DOI around the bore- a very shallow DOI around the bore- receivers provide ? exibility in the ways hole (cm or < m),” Seydoux says. “This hole (cm or < m),” Seydoux says. “This that the new system can be incorporated new technology (RMWD), provides a new technology (RMWD), provides a into the BHA. The multiple spacing structure with resistivity around the structure with resistivity around the between transmitters and receivers, borehole up to 30m. It is a much larger borehole up to 30m. It is a much larger along with multiple frequencies, pro- area and provides additional informa- area and provides additional informa- vide the best approach to address well tion not previously available. It is still tion not previously available. It is still placement in complex formations. This complementary with LWD, with integra- complementary with LWD, with integra- helps to correctly establish the location tion of information as a key aspect. tion of information as a key aspect. of oil water contact (OWC), while at the

Another important advantage is the link Another important advantage is the link same time unveiling the geometry of the to seismic. Because the technology DOI to seismic. Because the technology DOI reservoir, including estimating reservoir

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