A distributed device and method for detecting groundwater based on nuclear magnetic resonance are provided. The device includes an excitation apparatus, multiple polarization apparatuses, an aerial reception apparatus, and a control apparatus. The aerial reception apparatus includes an array cooled coil sensor. For each of the multiple polarization apparatuses, a position analysis module determines, together with a second position analysis module of the polarization apparatus, a position of the array cooled coil sensor relative to a polarization coil in the polarization apparatus. A polarization transmitter in the polarization apparatus switches to a mode of waiting for output in a case that the array cooled coil sensor is in coverage of the polarization coil. The polarization transmitter in the polarization apparatus remains in a standby mode in a case that the array cooled coil sensor is beyond coverage of the polarization coil.

A distributed device and method for detecting groundwater based on nuclear magnetic resonance are provided. The device includes an excitation apparatus, multiple polarization apparatuses, an aerial reception apparatus, and a control apparatus. The aerial reception apparatus includes an array cooled coil sensor. For each of the multiple polarization apparatuses, a position analysis module determines, together with a second position analysis module of the polarization apparatus, a position of the array cooled coil sensor relative to a polarization coil in the polarization apparatus. A polarization transmitter in the polarization apparatus switches to a mode of waiting for output in a case that the array cooled coil sensor is in coverage of the polarization coil. The polarization transmitter in the polarization apparatus remains in a standby mode in a case that the array cooled coil sensor is beyond coverage of the polarization coil.

An NMR logging system is disclosed which continues logging without interruption despite switching activation sets to adapt to changes in formation properties. Based on detection of an approaching or encountered geological boundary, an appropriate activation set is transmitted to the downhole NMR tool while the NMR tool continues logging. This system optimizes NMR data collection for each formation and associated formation fluid properties while reducing the need to stop the tool string movement while switching the activation set, and reduces incomplete collection of NMR and non-NMR logging tool data.

An NMR logging system is disclosed which continues logging without interruption despite switching activation sets to adapt to changes in formation properties. Based on detection of an approaching or encountered geological boundary, an appropriate activation set is transmitted to the downhole NMR tool while the NMR tool continues logging. This system optimizes NMR data collection for each formation and associated formation fluid properties while reducing the need to stop the tool string movement while switching the activation set, and reduces incomplete collection of NMR and non-NMR logging tool data.

A method and microfluidic device to perform reservoir simulations using pressure-volume-temperature (“PVT”) analysis of wellbore fluids.

A method and microfluidic device to perform reservoir simulations using pressure-volume-temperature (“PVT”) analysis of wellbore fluids.

Systems and methods for developing a reservoir that include obtaining well log data (conducting nuclear magnetic resonance (NMR), gamma ray (GR), and resistivity logging operations to generate corresponding NMR, GR and formation true resistivity logs for one or more wells in the reservoir), determining rock property data based on the well log data, determining a “water-zone baseline” based on the rock property data (e.g., based on a cross-plot of rock properties determined from the NMR and GR logs and resistivity values), and determining water saturation data based on the water-zone baseline.

Systems and methods for developing a reservoir that include obtaining well log data (conducting nuclear magnetic resonance (NMR), gamma ray (GR), and resistivity logging operations to generate corresponding NMR, GR and formation true resistivity logs for one or more wells in the reservoir), determining rock property data based on the well log data, determining a “water-zone baseline” based on the rock property data (e.g., based on a cross-plot of rock properties determined from the NMR and GR logs and resistivity values), and determining water saturation data based on the water-zone baseline.

In some embodiments, a method includes selecting a flip angle of refocusing pulses of a pulse sequence equal to a tip angle of an excitation pulse of the pulse sequence, wherein the flip angle is selected based on a lateral motion parameter of a nuclear magnetic resonance (NMR) sensor of a logging tool positioned in a wellbore formed in a subsurface formation. The method further includes emitting, from a transmitter of the logging tool into the subsurface formation, the pulse sequence comprising the tip angle and selected flip angle, and acquiring, by the NMR sensor, transversal NMR relaxation data generated in response to the emitted pulse sequence. The method also includes processing the transversal NMR relaxation data to assess a petrophysical parameter.

In some embodiments, a method includes selecting a flip angle of refocusing pulses of a pulse sequence equal to a tip angle of an excitation pulse of the pulse sequence, wherein the flip angle is selected based on a lateral motion parameter of a nuclear magnetic resonance (NMR) sensor of a logging tool positioned in a wellbore formed in a subsurface formation. The method further includes emitting, from a transmitter of the logging tool into the subsurface formation, the pulse sequence comprising the tip angle and selected flip angle, and acquiring, by the NMR sensor, transversal NMR relaxation data generated in response to the emitted pulse sequence. The method also includes processing the transversal NMR relaxation data to assess a petrophysical parameter.