... wells waiting to be sidetracked were used for injection. Most injection has been performed in Tertiary shales in the overburden, but also horizontal wells in the chalk reservoirs have been used. The perforations have been placed mainly in Tertiary shales to reduce risk of screen-out. Leak-off taking...

... arise. Rock strength anisotropy in shale causes significant instability in high-angle wells. Misconceptions about instability mechanisms and reluctance to use higher mud weight (MW) often lead to wellbore instability and Non-Productive Time (NPT). Despite many wells being drilled through unstable shale...

... be as high as 100 kN. The more advanced rock mechanics model indicates there is a mechanism in an interval with fractured shales in Lower Hordaland formation where the problems occurred on the trips out. Fluid invasion into fractures, cyclic ECD pressure and gravity is driving the deformation. We see...

... Abstract Annular shale creep barriers which can guarantee long-term well integrity over the entire lifespan of the well can be stimulated by temperature elevation caused by artificial heating inside the wellbore. Prior work has shown that heating can significantly accelerate barrier formation...

... with machine learning. geology prediction clastic rock wellbore integrity geologist rock type sedimentary rock wellbore design geological subdiscipline gradient resistivity module shale reservoir characterization drilling petroleum engineer wellbore stability update example reservoir...

... The equations above are valid for a non-penetrating situation where the wellbore pressure is higher than the pore pressure due to the presence of a filter cake, or for shale, a high enough capillary entry pressure, on the wellbore wall. If the wellbore pressure drops below the pore pressure...

... without application of damaging weighting solids. The drilling fluid contributed to successful MPD and delivered wells with very good hole quality in the reservoir, which consisted of interbedded sandstone, coal stringers and shale. The shale stabilising properties of concentrated formate brine–based...

...-setting grouts (Type B), thermosetting polymers and composites (Type C), thermoplastic polymers and composites (Type D), elastomeric polymers and composites (Type E), rock formation (Type F), gels (Type G), glasses (Type H), metals (Type I) and modified in-situ materials (Type J). Using shale or salt...

... Abstract Several wells in the Gulf of Mexico were analyzed to understand the source of shale instability during drilling and wireline operations. In spite of the mud weight being above the borehole collapse pressure, the wells still exhibited signs of shale instability. As such, it was evident...

... out during the experiment, and the breakthrough pressure observed during the leak-off test at the end of the test. Experiment Annular Closure / Barrier Formation Time Permeability of shale barrier Breakthrough pressure during leak-off test Base Test 18.2 days 10.1 μD @ 10.5 days...

... for shale applications focusing on efficient cuttings removal, geometry B for proper fracture initiation and propagation, and geometry C combines the features from the other two geometries to improve both creation and removal of cuttings. The geometries were optimized for maximum rock cutting efficiency...

... pressure mud weight window overpressure drilling campaign minimum horizontal stress strength shale prognosis Upstream Oil & Gas prediction collapse gradient well path compartment vertical stress digitized uncertainty handling international association of drilling contractors fracture...

... To illustrate the challenge at hand, Fig.1 reproduces relatively recent advice by a major integrated service company (Stephens et al., 2009) on the selection of appropriate fluid-shale compatibility tests. Two key observations are made: (1) the recommended tests include conventional test...

... kobbe sequence 4 Upstream Oil & Gas pre-job modeling Reservoir Characterization LWD Kobbe lower kobbe sand unit OWC shale density image reservoir section sequence 3 kobbe 9 DDR inversion inclination resistivity kobbe 8 inversion wellbore Introduction Goliat field locates...

... Abstract Tor/Ekofisk wells drilled in the Danish sector of the North Sea have historically suffered from borehole instability problems when intersecting the Upper/Lower Lark and Horda shale formations using either water-based mud (WBM) or oil-based mud (OBM). An extensive wellbore stability...

... Reservoir Characterization pore pressure Pore Pressure Estimation pore pressure estimate reservoir geomechanics Efficiency drilling efficiency trendline mechanical specific energy DEMSE method pressure estimation method drilling efficiency differential pressure Upstream Oil & Gas shale...

... Abstract Polycrystalline Diamond Compact (PDC) fixed cutter drill bits have provided significant breakthrough to the drilling industry by extending the boundaries from softer formations, such as shale into harder rocks, such as limestone. The emphasis of this technology is on reducing costs...

... Intelligence Upstream Oil & Gas differential borehole pipe borehole cleaning sticking equation BHA international association of drilling contractors key seating mud weight shale formation pressure drill string prediction coefficient indication drilling fluid Background Stuck pipe...

... production loss and avoiding risk associated with well shut-in and start-up. drilling operation wellpath BHA drill-bit Conductor close proximity assembly weak formation collision trajectory shale directional operator sediment RSS system Upstream Oil & Gas flow rate rotation...

... conformed by a 9 5/8″ casing, 6-5/8″ screen, gravel, cement and borehole was built in a Finite Element Analysis Software (Plaxis). The target reservoir model consisted of turbidities sandstones with low permeability, with an impermeable shale layer inserted in between the sandstones. The input parameters...