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.
Abstract:
Processes for determining formation salinity and/or processes for identifying oil bearing and/or water bearing zones in freshwater or relatively low salinity formations. In some embodiments, the process for determining formation water salinity can include measuring resistivity of a formation fluid sample at a first temperature (T1) and at a second temperature (T2), where T1 and T2 can be separated by a temperature difference (ΔT). The process can also include calculating a resistivity factor value based on the resistivities measured at T1 and T2. The process can also include determining a salinity of the formation fluid sample based on the resistivity factor value and the ΔT. The process can also include initiating a downhole operation using the determined salinity of the formation fluid sample.
Abstract:
Processes for characterizing reservoir formation parameters such as water salinity and water saturation. In some embodiments, the process can include directing a heat impulse into a formation sample that can include a matrix component and a fluid component at an input location. The heat impulse can be allowed to pass through the formation sample such that a matrix impulse forms through the matrix component and a fluid impulse forms through the fluid component. The matrix and fluid impulses can convolve at a measurement location to provide a convolved impulse. A derivative analysis of the convolved impulse can be performed to derive thermal transient measurements. A fluid thermal model can be developed using the thermal transient measurements. The fluid thermal model can be integrated with one or more downhole logs and/or input parameters to create an integrated model. One or more reservoir parameters can be determined from the integrated model.
Abstract:
Processes for characterizing reservoir formations and directing downhole operations based on the characterized reservoir formations. In some embodiments, the process can include combining at least two downhole logs into input data. An interpretation method can be used to convert the input data into interpretative data. Elemental analysis can be used to convert the interpretative data into at least one formation model. Formation properties can be acquired from the at least one formation model. A reservoir quality classification can be created from the formation properties. The process can also include directing downhole operations using the reservoir quality classification to select a preferred downhole operation location.
Abstract:
Methods and systems are provided for characterizing connate water salinity and resistivity of a subsurface formation. Well log data including resistivity and spontaneous potential (SP) log data are measured by at least one downhole tool disposed within a borehole. The resistivity and SP log data are inverted to determine a resistivity model and an SP model, which are used to determine connate water resistivity. The connate water resistivity is used to determine connate water salinity. The connate water salinity derived from the inversion of resistivity log data and SP log data (or derived from a trained ML system supplied with such log data) can be used as a baseline measure of connate water salinity, and this baseline measure can be evaluated together with the connate water salinity estimates derived from pulsed neutron tool measurements over time-lapsed periods of production to monitor variation in connate water salinity due to production.
Abstract:
A method can include receiving downhole formation testing time series data acquired at a location along a borehole in a subsurface region during a formation testing operation performed by a downhole tool; processing the downhole formation testing time series data using a machine learning model to generate smoothed time series data; resampling the smoothed time series data; generating fluid and formation characteristics with respect to time based on the smoothed time series data; and outputting the fluid and formation characteristics with respect to time.
Abstract:
A method can include receiving petrophysics data acquired along a borehole in a subsurface region; generating test location recommendations along the borehole using the petrophysics data as input to a machine learning model; and outputting, based on the test location recommendations, selected locations for performing tests using a downhole tool disposed in the borehole
Abstract:
Methods and systems are provided that employ a combination of dielectric dispersion measurement(s) and Nuclear Magnetic Resonance (NMR) measurement(s) to determine data that characterizes tortuosity of rock and data that characterizes tortuosity of fluid phases in the rock independently from one another.
Abstract:
Methods and systems are provided that employ a combination of dielectric dispersion measurement(s) and Nuclear Magnetic Resonance (NMR) measurement(s) to determine data that characterizes tortuosity of rock and data that characterizes tortuosity of fluid phases in the rock independently from one another. t,?
Abstract:
Methods and systems are provided for clay detection, clay typing, and clay volume quantification using downhole electromagnetic measurements conducted by a downhole logging tool on a formation at a low frequency less than 5000 Hz. The downhole electromagnetic measurements are used to determine permittivity data that characterizes permittivity of the formation at the low frequency less than 5000 Hz. The downhole low frequency electromagnetic measurements are nondestructive, and the results indicate it is with high sensitivity to the existence of clays.