Abstract: An optical fiber (FD) that can be used for measuring pressure is arranged as follows. The optical fiber (FD) comprises a core (CO) and a cladding (CL) surrounding and contacting the core (CO). A stress-applying arrangement (SE1, SE2), which is embedded in the cladding (CL), applies constant anisotropic stress on the core (CO). This causes the core (CO) to exhibit a deformation. A pressure conversion arrangement (HO1, H02), which is also embedded in the cladding (CL), converts isotropic external pressure applied to the optical fiber (FD) into pressure-dependent anisotropic stress applied to the core (CO). The pressure conversion arrangement (HO1, H02) is disposed with respect to the stress-applying arrangement (SE1, SE2) so that the pressure-dependent anisotropic stress enhances the deformation of the core (CO) caused by the constant anisotropic stress.

Abstract: The present invention provides means to seal voids and cracks in subterranean-formation rock that contains carbonate minerals, thereby minimizing or stopping fluid flow between the formation rock and the wellbore of a subterranean well. The methods comprise pumping a solution of one or more lattices that contain at least one carboxylated monomer down a well and allowing it to enter voids (e.g., pores, fractures, vugs and caverns) in the carbonate-containing formation, whereupon it reacts with divalent cations liberated by the carbonates and forms a gel.

Abstract: An improved apparatus and a method to insert a wireline through a blow out preventer to log an underbalanced open hole well without killing the well or causing formation damage while maintaining well control during the process. A dual throated blow out preventer (10) provides a moveable sealing element (1210, 1402) to allow a wireline (13) and a drill string (25) to be placed in a well for assembly, then seals off the dual throat to isolate the drill string from the wireline, thereby permitting pressure to be maintained on both the wireline through a standard packoff arrangement (1218) and on the drill string using the rams of the blow out preventer (10).

Abstract: A system for real-time data surveillance in an oilfield operation includes a data collection system deployed at a well site for collecting oilfield data; an office-based computer system for storing and analyzing the oilfield data; a portable device, wherein the portable device includes at least one program for communicating with the office-based computer system, for surveying the oilfield data stored in the office-based computer system, and for causing the office-based computer system to perform a process implemented on the office-based computer system; and a communication system providing communication links among the data collection system, the office-based computer system, and the portable device.

Abstract: A drilling fluid delivery system for use in drilling boreholes with a drill bit, the system comprising: a primary flow circuit having a relatively high flow rate for transferring drilling fluid to and from the drill bit; a secondary flow circuit having a relatively low flow rate for transferring drilling fluid to and from the primary flow circuit; and a cuttings transfer system, such as a hydrocyclone or a rotating filter, between the primary and secondary flow circuits which, in use, receives fluid containing cuttings from the primary circuit, separates the fluid into a first stream that contains substantially no cuttings and a second stream containing cuttings, the first stream being returned to the primary flow circuit and the second stream being directed to the secondary flow circuit.

Abstract: A method and system is disclosed for automatically correcting for depth errors in measurements taken from a drill-string during the drilling phase of the construction of a hydrocarbon wellbore. The correction is based on a stress profile which in turn is based on the states of the drilling rig, drill string description length spec, borehole description trajectory, friction factor and weight on bit.

Abstract: Apparatus for drilling operations in underground boreholes, comprises: a drilling assembly that can be located in a borehole and is moved along the borehole during the drilling operation; a flexible fluid supply line connected to and in fluid communication with the drilling assembly and extending from the drilling assembly to the surface when the drilling assembly is in the borehole; and an electric cable for providing electric power to the drilling assembly and extending from the drilling assembly to the surface when the drilling assembly is in the borehole; the fluid line and the electric cable are separate, and the electric cable being outside the fluid line. A method for conducting drilling operations using an apparatus as defined above, comprises operating the drilling assembly and directing fluid between the surface and the drilling assembly via the flexible fluid line.