Estimating wear on bottom hole assembly (BHA) components utilizes a rock hardness index using analysis of drill cutting. Estimating the amount of wear on borehole assembly components comprises measuring the rock properties in drilled cuttings from a borehole. A hardness value is assigned to each mineral present in the drilled cuttings. A hardness index is calculated for a drilled borehole interval. A wear resistance factor is assigned to each BHA component of the BHA. The wear resistance factor depends on the wear resistance of each BHA component. A wear value for each BHA component is calculated based on the hardness index for the drilled borehole interval, the wear resistance of the BHA component, and drilling parameters.

Estimating wear on bottom hole assembly (BHA) components utilizes a rock hardness index using analysis of drill cutting. Estimating the amount of wear on borehole assembly components comprises measuring the rock properties in drilled cuttings from a borehole. A hardness value is assigned to each mineral present in the drilled cuttings. A hardness index is calculated for a drilled borehole interval. A wear resistance factor is assigned to each BHA component of the BHA. The wear resistance factor depends on the wear resistance of each BHA component. A wear value for each BHA component is calculated based on the hardness index for the drilled borehole interval, the wear resistance of the BHA component, and drilling parameters.

A drill hole logging system (5) incorporates a computing system (58) at the surface and a deployment mechanism (40) for conveying a logging tool (10) configured to measure one or more geophysical parameters into a drill hole (20). A transmission means (57) communicates commands and data representing the geophysical parameters between the surface computing system and the logging tool. A borehole caliper (300) is employed to profile the inside of the borehole.

A drill hole logging system (5) incorporates a computing system (58) at the surface and a deployment mechanism (40) for conveying a logging tool (10) configured to measure one or more geophysical parameters into a drill hole (20). A transmission means (57) communicates commands and data representing the geophysical parameters between the surface computing system and the logging tool. A borehole caliper (300) is employed to profile the inside of the borehole.

An object of the disclosure is to determine the remaining saturation of existing fluids in naturally fractured and/or homogeneous reservoirs, considering an unconventional tracer test, using the double tracer test method with pressure monitoring (PDTcMP®), which also integrates unused technical elements, in order to estimate more accurately the value of the remaining oil saturation (ROS) in naturally fractured reservoirs, unlike conventional methods used most commonly in homogeneous media. The disclosure substantially modifies the conventional tracer test, as it uses innovative technical elements, which reduce the uncertainty and/or ambiguity associated with conventional tracer tests, when they are applied in naturally fractured reservoirs.

An object of the disclosure is to determine the remaining saturation of existing fluids in naturally fractured and/or homogeneous reservoirs, considering an unconventional tracer test, using the double tracer test method with pressure monitoring (PDTcMP®), which also integrates unused technical elements, in order to estimate more accurately the value of the remaining oil saturation (ROS) in naturally fractured reservoirs, unlike conventional methods used most commonly in homogeneous media. The disclosure substantially modifies the conventional tracer test, as it uses innovative technical elements, which reduce the uncertainty and/or ambiguity associated with conventional tracer tests, when they are applied in naturally fractured reservoirs.

An x-ray based litho-density tool for measurement of simultaneous invaded and non-invaded formation surrounding a borehole is provided, the tool including at least an internal length comprising a sonde section, wherein sonde section further includes an x-ray source; at least one radiation measuring detector; at least one source monitoring detector; and a plurality of sonde-dependent electronics. In various embodiments, the tool uses x-rays to illuminate the formation surrounding a borehole, and a plurality of detectors are used to directly measure both invaded and non-invaded formation bulk densities. Detectors used to measure borehole standoff such that other detector responses may be compensated for tool standoff; long and ultra-long space detectors disposed in electromagnetic communication with a source located within a collimated tungsten radiation shield; and wear-pads disposed such that the source and detector assembly may be pressed against the side of the borehole to reduce borehole effects are also provided.

An x-ray-based cement evaluation tool for determining whether a cement bond exists between the casing and cement of a cemented borehole is provided, the tool including at least: an internal length comprising a sonde section, wherein said sonde section further comprises an x-ray source; a radiation shield for radiation measuring detectors; arrayed pixelated detectors; sonde-dependent electronics; and a plurality of tool logic electronics and PSUs. A method of using an x-ray-based cement evaluation tool for measuring a cement bond between a casing and the cement of a cemented borehole is also provided, the method including: producing x-ray in a conical beam to illuminate a well casing; measurement of the returning photons as a function of radial and axial offset; remapping the intensity of returning photons to a geometric response within the casing and cement; and determining whether an annulus is present between the casing and cement.

An x-ray based litho-density tool for measurement of formation surrounding a borehole is provided, the tool including at least an internal length comprising a sonde section, wherein said sonde section further comprises an x-ray source; at least one radiation measuring detector; at least one source monitoring detector; a plurality of sonde-dependent electronics; and a reference detector, wherein the reference detector is used to monitor the output of the x-ray source such that the reference detector's output effects corrections to the outputs of the detectors used to measure the density of the materials surrounding the borehole in order to correct for variations in the x-ray source output. Tool logic electronics, PSUs, and one or more detectors used to measure borehole standoff such that other detector responses may be compensated for tool standoff are also provided.

Shielding, through-wiring, wear-pads that improve the efficacy and tool functionality are also described and claimed.

Through-tubing, cased-hole sealed material density can be evaluated using gamma ray measurements. Density evaluation comprises detecting, by at least one detector positioned within a casing of a wellbore including a sealing material positioned between the casing and a subsurface formation, electromagnetic radiation generated in response to nuclear radiation being emitted outward toward the subsurface formation, determining an electromagnetic radiation count based on the detected electromagnetic radiation, selecting at least one of a first reference material having a density that is less than a density of the sealing material and a second reference material having a density that is greater than the density of the sealing material, adjusting the electromagnetic radiation count based on the density of the at least one of the first reference material and the second reference material, and determining a density of the sealing material based on the adjusted electromagnetic radiation count.