Method and apparatus for measuring oil content of tight reservoir based on nuclear magnetic resonance

An apparatus for measuring oil content of a tight reservoir based on nuclear magnetic resonance, comprising:

• a pulse sequence and magnetic field application module configured to execute a pulse sequence and magnetic field application step:
• applying a pulse sequence to a tight reservoir rock, and after applying a first pulse and a last pulse in the pulse sequence, applying a gradient magnetic field to the tight reservoir rock, respectively, directions of the applied gradient magnetic field applied twice being opposite to each other, wherein the pulse sequence is composed of three 90° pulses;
• a nuclear magnetic resonance signal acquisition module configured to acquire a nuclear magnetic resonance signal of the tight reservoir rock;
• a tight reservoir rock oil content determination module configured to determine oil content of the tight reservoir rock according to an intensity of the nuclear magnetic resonance signal;
• a signal type judgment unit configured to judge whether a type of the nuclear magnetic resonance signal is an echo signal;
• and
• an oil phase nuclear magnetic resonance signal determination unit configured to determine that the nuclear magnetic resonance signal is an oil phase nuclear magnetic resonance signal, if the type of the nuclear magnetic resonance signal is an echo signal.

An electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable in the processor, wherein when executing the computer program, the processor realizes steps of a method for measuring oil content of a tight reservoir based on nuclear magnetic resonance, comprising:

• a pulse sequence and magnetic field application step:
• applying a pulse sequence to a tight reservoir rock, and after applying a first pulse and a last pulse in the pulse sequence, applying a gradient magnetic field to the tight reservoir rock, respectively, directions of the gradient magnetic field applied twice being opposite to each other, wherein the pulse sequence is composed of three 90° pulses;
• acquiring a nuclear magnetic resonance signal of the tight reservoir rock;
• and
• determining oil content of the tight reservoir rock according to an intensity of the nuclear magnetic resonance signal,
• wherein before determining oil content of the tight reservoir rock according to an intensity of the nuclear magnetic resonance signal, the method includes
• judging whether a type of the nuclear magnetic resonance signal is an echo signal;
• and
• if yes, determining that the nuclear magnetic resonance signal is an oil phase nuclear magnetic resonance signal.

A computer readable storage medium which stores a computer program, wherein when being executed by a processor, the computer program realizes steps of a method for measuring the oil content of the tight reservoir based on nuclear magnetic resonance, comprising:

• a pulse sequence and magnetic field application step:
• applying a pulse sequence to a tight reservoir rock, and after applying a first pulse and a last pulse in the pulse sequence, applying a gradient magnetic field to the tight reservoir rock, respectively, directions of the gradient magnetic field applied twice being opposite to each other, wherein the pulse sequence is composed of three 90° pulses;
• acquiring a nuclear magnetic resonance signal of the tight reservoir rock;
• and
• determining oil content of the tight reservoir rock according to an intensity of the nuclear magnetic resonance signal,
• wherein before determining oil content of the tight reservoir rock according to an intensity of the nuclear magnetic resonance signal, the method includes
• judging whether a type of the nuclear magnetic resonance signal is an echo signal;
• and
• if yes, determining that the nuclear magnetic resonance signal is an oil phase nuclear magnetic resonance signal.

A system for measuring the oil content of the tight reservoir based on nuclear magnetic resonance, comprising a control component, and a nuclear magnetic resonance spectrometer communicatively connected to the control component;

• the nuclear magnetic resonance spectrometer is provided therein with a sample compartment that contains a tight reservoir rock;
• the control component is configured to send a control signal to the nuclear magnetic resonance spectrometer;
• the nuclear magnetic resonance spectrometer executes a pulse sequence and a magnetic field application step on the tight reservoir rock according to the control signal:
• applying a pulse sequence to a tight reservoir rock, and after applying a first pulse and a last pulse in the pulse sequence, applying a gradient magnetic field to the tight reservoir rock, respectively, directions of the gradient magnetic field applied twice being opposite to each other, wherein the pulse sequence is composed of three 90° pulses;
• acquiring a nuclear magnetic resonance signal of the tight reservoir rock;
• sending the nuclear magnetic resonance signal to the control component;
• the control component is further configured to determine oil content of the tight reservoir rock according to an intensity of the nuclear magnetic resonance signal,
• wherein the control component is further configured to judge whether a type of the nuclear magnetic resonance signal is an echo signal;
• and if the nuclear magnetic resonance signal is the echo signal, determine that the nuclear magnetic resonance signal is an oil phase nuclear magnetic resonance signal, and determine the oil content of the tight reservoir rock according to the intensity of the oil phase nuclear magnetic resonance signal.