GEOSTEERING SPECIALIST Saudi Geophysical Consulting's Geosteering Specialist are experience whether the job is based on GR/ROP or full triple or quad combo, or whether it involves picking dips from real-time images, GeoSteering Services provides 24/7 real-time cover on individual wells from client offices or from any premises. Our client's geosteering software, runs in real-time allowing our users to watch data streaming from MWD/LWD, mudlogging and rig instrumentation systems in many different environments. This is realtime geology data streaming for horizontal drilling. The geosteering software (Halliburton,Schlumberger, Baker Hughes, Precision Drilling and others) allows the users to watch data from MWL/LWD, mudloging and rig instrumentation systems in realtime and have a coverage of 24/7. Here is Saudi Arabia, we are using geosteering purposes we are using aside of GR, azimutal GR and density image log also distance-to-boundary resistivity tools – azimutal provided by Schlumberger, Halliburton and Baker and non-azimutal, based on modeling, provided by Weatherford. We also use reservoir evaluation tools to steer within thick reservoirs, that are formation testers and NMR tools (magnetic resonance) first giving permeability readings (point analyses) and second giving fluids movability and under some restrictions also permeability (with some special modeling requirement) – continuous readings. Mentioning tools providers are among others: Schlumberger and Halliburton, Baker Hughes Inteq, PathFinder and sometimes Precision Drilling (it was recently bought out by Weatherford and now uses their trademark). To steer the well we are using operator specific software for the real-time analyses supported by Landmarks StratWorks for correlations and also cross-section and map projection for structural control. All the geosteering functionality of the offline software is also available in realtime, plus the user can monitor both the drilling and directional parameters such as toolface and rotary steerable settings. All LWD measurements are supported, regardless of vendor, including realtime image logs. Realtime information can make all the difference in many situations. Technical Geosteering Technical geosteering is a computational signal-mapping task. Timely and depth-accurate logging while drilling formation evaluation (LWDFE) data is transformed—using a geometric location estimate of a marker bed—to plot on a representative stratigraphic type log. An acceptable “fit” suggests a good estimate of the marker bed location. Gamma Ray The most common LWDFE measurement applied to technical geosteering is omni-directional gamma ray. Gamma ray is chosen because of its relatively insensitive signal response to varying pore fluids, rock porosity, rock permeability, and circumferential borehole quality. Another favorable gamma ray attribute is a short depth of investigation (e.g., 4-6 inches); with less rock “seen” by the tool there is less chance for signal complication. In oil and gas geosteering applications the measured depth (MD) frequency of gamma ray data is typically 0.5 or 1 ft, which enables fault-crossing recognition. Some operations rely on focused gamma ray measurements (e.g., borehole high side and low side readings) to either outright drive technical geosteering or to augment interpretations relying primarily on omni-directional gamma ray measurements. 3D Curved World What complicates the software engine of technical geosteering is addressing the fact that both the well path (known-location) and the payzone (unknown-location) simultaneously change and curve in three-dimensional (3D) space. A two-dimensional (2D) technical geosteering analysis—one based on vertical section for example—inherently suppresses resolution and introduces distortion, especially with ‘3D’ wells and or ‘2D’ wells with thin payzones. 3D Technical Geosteering In 2006, Stoner Engineering LLC developed a 3D technical geosteering methodology that eliminates the shortcomings of 2D analysis. Two new geologic terms resulted from this work: 3DStratBlock and relative stratigraphic depth. There has been a steady progression in the vertical depth and horizontal departure length of ERD wells. In Saudi Arabia, development drilling programs increasingly require directionally drilled well trajectories to reach the bottom hole targets. Recent developments in horizontal well-placement and drilling technology enabled us to successfully drill and geosteer one of the longest openhole power water injector wells in Saudi Arabia. Complexities in the placement of this extended reach well located on the flank of a field included : 1) A target that was characterized by high formation dip and 2) No offset well control, leading to the reservoir having unknown structural dip and azimuth. It is also common for ERD-well paths to cross faults, sometimes with unfavorable displacements and orientations. Advance geosteering methods using 3D visualization and real-time borehole images were utilized to detect a sub-seismic fault, and successfully side track and steer the well to remain in good porosity for the entire horizontal section. Real-time images enabled an accurate depiction of the formation dip. Combined with 3D structural modeling updates, this approach proved invaluable in successfully placing this extended reach borehole. Figure 01. Geosteering Planned trajectory versus Drilled trajectory. Actually most of our specialist are working in Saudi Arabia, but they ara capable to perform services anywhere in the world. Please contact us for further details about our GEOSTEERING SPECIALIST Services.