公开(公告)号：US20190113649A1

公开(公告)日：2019-04-18

申请号：US16157480

申请日：2018-10-11

Applicant: PetroChina Company Limited

Inventor： Hua TIAN ,  Shuichang ZHANG ,  Shaobo LIU ,  Caineng ZOU ,  Keyu LIU ,  Xuesong LU ,  Mengjun ZHAO ,  Lin JIANG ,  Xingzhi MA ,  Bin ZHANG ,  Junjia FAN ,  Peiqiang YANG

IPC: G01V3/32 ,  G01N24/08 ,  G01R33/561 ,  G01R33/44 ,  G01R33/54 ,  G01R33/483

Abstract: A method and an apparatus for measuring oil content of a tight reservoir based on nuclear magnetic resonance includes 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 two applied gradient magnetic fields 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. The method can accurately distinguish an oil phase nuclear magnetic resonance signal and a water phase nuclear magnetic resonance signal in nanopores of tight reservoir rock, thereby effectively improving the accuracy of the detection result of the oil content of the tight reservoir rock.