Abstract:
A downhole tool to make one or more downhole measurements of laser-induced vaporization and/or pyrolysis of hydrocarbons is provided and disposed at a desired location within a wellbore. A tool head of the downhole tool is brought into sealing engagement with the wellbore wall. The fluid within an interior region enclosed by the tool head and the wellbore wall is evacuated and a measurement spot is irradiated with a laser to generate volatile hydrocarbons and/or pyrolytic hydrocarbons. Measurements are made on the volatile hydrocarbons and/or pyrolytic hydrocarbons and one or more formation properties are inferred based on the measurements. A low level of laser radiation intensity, irradiating some or all of the wellbore wall enclosing the interior region, may be used to prevent measurement contamination, and both medium power and high power levels of laser radiation may be used to first vaporize and then pyrolyze the hydrocarbons.
Abstract:
An apparatus including a body having a central axis defined therethrough, at least one extendable arm coupled to the body, and a mechanical property tester coupled to the at least one extendable arm, the mechanical property tester configured to penetrate a surface of a borehole and to measure one or more mechanical properties of the surface of the borehole.
Abstract:
A drill string includes drill pipe and a modular fracturing sub. A processor can control the drill string to drill a wellbore to some desired depth. The drill string is positioned at a desired location in the wellbore and a section of the wellbore is hydraulically isolated, forming a cavity. Existing fluid may be evacuated from the cavity and fracturing fluid injected into the cavity until a desired level of fracturing is attained. Retrievable packers are used for the hydraulic isolation. A pump evacuates the existing fluid via ports in the fracturing sub. The ports may also be used when injecting fracturing fluid. Seismic sensors may be distributed along the drill string to monitor fracture growth. Logging-while-drilling tools may be integrated into the drill string. Fluid from the lower portion of the wellbore is blocked by a lower sealing unit on a bottomhole assembly.
Abstract:
A NMR logging tool is provided and disposed at some desired depth in a wellbore penetrating a subsurface formation. A first set of NMR measurements is made over a desired depth range and depth of investigation, wherein the first set of NMR measurements includes a first NMR signal intensity. Supercritical carbon dioxide is injected into the formation and a second set of NMR measurements is made over the desired depth range and depth of investigation, wherein the second set of NMR measurements includes a second NMR signal intensity. The first NMR signal intensity is compared to the second NMR signal intensity and one or more properties of the formation are inferred using the compared NMR measurements. A magnetic field gradient that varies a static magnetic field along a desired spatial dimension of a region of investigation may be provided to map a rate of fluid movement.
Abstract:
Systems and methods are described for controlling the location where a fracture initiates and the fracture direction at the initiation point. A mechanical device is positioned in a main wellbore or partially or fully in a side hole off of the main wellbore. The mechanical device is actuated so as to contact the formation walls and induce stress in the formation. According to some embodiments, fractures are also initiated using the mechanical device. A hydraulic fracturing process is then carried out to fracture and/or propagate fractures in locations and/or directions according to the actuation of the mechanical device.
Abstract:
Methods are provided for separating oil and water signals in multidimensional nuclear magnetic resonance (NMR) maps. In one embodiment, separate multidimensional NMR maps are provided for oil and water content. In another embodiment, an oil-water boundary and a water-gas boundary are generated on a D-T2 map. The boundaries may be curved boundaries or lines.