阅读说明：本技术 一种应用核磁共振四边形解释图版识别流体性质的方法 (Method for identifying fluid property by applying nuclear magnetic resonance quadrilateral interpretation plate ) 是由 杨琳 唐家琼 尹平 唐谢 罗诚 罗异 赵磊 阮聪 刘达贵 曹玉 于 2020-05-22 设计创作，主要内容包括：本发明公开了一种应用核磁共振四边形解释图版识别流体性质的方法,涉及油气地质勘探录井解释评价技术领域,其步骤是：原始参数选择：选择四个用于建立解释图版的参数,分别是：分别是<Image he="22" wi="14" file="100004_DEST_PATH_IMAGE002.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>、<Image he="22" wi="14" file="973019DEST_PATH_IMAGE002.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>S<Sub>束缚水</Sub>、<Image he="22" wi="14" file="624580DEST_PATH_IMAGE002.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>S<Sub>可动水</Sub>、<Image he="22" wi="14" file="873159DEST_PATH_IMAGE002.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>S<Sub>气</Sub>；图版框架建立：该解释图版为四边形图版,以<Image he="22" wi="14" file="737210DEST_PATH_IMAGE002.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>值可取刻度范围为横轴一、<Image he="22" wi="14" file="535270DEST_PATH_IMAGE002.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>S<Sub>气</Sub>值可取刻度范围为横轴二,建立横坐标,以<Image he="22" wi="14" file="92153DEST_PATH_IMAGE002.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>S<Sub>束缚水</Sub>值可取刻度范围为纵轴一、<Image he="22" wi="14" file="93607DEST_PATH_IMAGE002.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>S<Sub>可动水</Sub>值可取刻度范围为纵轴二,建立纵坐标,两个横坐标与两个纵坐标相交围合形成四边形解释图版；数据分析步骤；核磁共振四边形解释图版建立步骤；核磁共振四边形解释图版解释步骤；本方法可高效、便捷地识别样品流体性质,为储层流体性质识别研究奠定了基础。(The invention discloses a method for identifying fluid properties by applying a nuclear magnetic resonance quadrilateral interpretation chart, which relates to the technical field of interpretation and evaluation of oil and gas geological exploration logging, and comprises the following steps: original parameter selection: four parameters for creating an interpretation plate were chosen, respectively: are respectively 、 S Bound water 、 S Movable water 、 S Qi (Qi) (ii) a Establishing a plate frame: the interpretation plate is a quadrangular plate to The scale range of the value can be taken as a horizontal axis, S Qi (Qi) The scale range of which the value can be taken is a second horizontal axis, and a horizontal coordinate is established so as to S Bound water The scale range of the value can be taken as the vertical axis, S Movable water The value scale range can be taken as a second longitudinal axis, a vertical coordinate is established, and the two horizontal coordinates and the two vertical coordinates are intersected and enclosed to form a quadrilateral interpretation plate; a data analysis step; establishing a nuclear magnetic resonance quadrilateral explanation plate; interpreting a nuclear magnetic resonance quadrilateral interpretation chart; the method can efficiently and conveniently identify the properties of the sample fluid, and lays a foundation for reservoir fluid property identification research.)

1. A method for identifying fluid properties by applying a nuclear magnetic resonance quadrilateral interpretation plate, characterized in that:

original parameter selection: four parameters for creating an interpretation plate were chosen, respectively: are respectively、S_{Bound water}、S_{Movable water}、S_{Qi (Qi)}；

Wherein:sample porosity measured for nmr logging, unit: percent;

S_{bound water}Sample irreducible water saturation measured for nmr logging, unit: percent;

S_{movable water}Sample mobile water saturation measured for nmr logging, unit: percent;

S_{qi (Qi)}The gas saturation of a sample for nuclear magnetic resonance measurement logging is as follows: percent;

establishing a plate frame: the interpretation plate is a quadrangular plate toThe scale range of the value can be taken as a horizontal axis,S_{Qi (Qi)}The scale range of which the value can be taken is a second horizontal axis, and a horizontal coordinate is established so as toS_{Bound water}The scale range of the value can be taken as the vertical axis,S_{Movable water}The value scale range can be taken as a second longitudinal axis, a vertical coordinate is established, and the two horizontal coordinates and the two vertical coordinates are intersected and enclosed to form a quadrilateral interpretation plate;

and (3) data analysis: taking a nuclear magnetic resonance sample of a certain work area as an example, obtaining the sample、S_{Bound water}、S_{Movable water}、S_{Qi (Qi)}Are respectively marked on the horizontal axis oneThe value is set as point A; on the longitudinal axis oneS_{Bound water}Setting the value as a B point; on the second transverse axisS_{Qi (Qi)}The value is set as point C; on the second longitudinal axisS_{Movable water}The value is set as point D; connecting the AC and the BD to obtain two broken lines which intersect at a point E, wherein the point E is an analysis point of the quadrilateral interpretation plate;

establishing a nuclear magnetic resonance quadrilateral interpretation plate: obtaining analysis points of a plurality of samples of nuclear magnetic resonance of a certain work area in a data analysis step mode, dividing a fluid property area according to specific positions of the analysis points of different oil testing results in a nuclear magnetic resonance quadrilateral explanation plate, and establishing the nuclear magnetic resonance quadrilateral explanation plate;

interpretation of nuclear magnetic resonance quadrilateral plates: and calculating analysis points of the porosity, the gas saturation, the bound water and the movable water of the nuclear magnetic resonance analysis of the sample according to the data analysis steps, then placing the analysis points in a nuclear magnetic resonance quadrilateral explanation plate, and judging the fluid property in the sample according to the area where the analysis points are located.

2. The method of claim 1, wherein the fluid property is identified using a nmr quadrilateral interpretation plate, the nmr quadrilateral interpretation plate comprising: and the scale ranges of the horizontal coordinate and the vertical coordinate control the maximum and minimum scale values of the coordinates according to the actual conditions of the work area.

3. The method of claim 1, wherein the fluid property is identified using a nmr quadrilateral interpretation plate, the nmr quadrilateral interpretation plate comprising: the coordinates are normal coordinates or logarithmic coordinates.

Technical Field

The invention relates to the technical field of interpretation and evaluation of oil and gas geological exploration logging, in particular to a nuclear magnetic resonance logging interpretation and evaluation method mainly suitable for natural gas reservoirs.

Background

Natural gas reservoir fluid property identification is an important task for guiding oil and gas exploration and development. In the drilling process, the fluid properties are mostly identified by adopting a logging interpretation technology, but in the prior art, logging parameters such as gas logging, drilling fluid and the like are mainly adopted for relevant analysis, and the parameters are easily influenced by uncertain factors such as working conditions, climate and the like, so that the logging interpretation is complex, and the fluid properties are difficult to identify effectively. The technology can quantitatively detect parameters such as sample porosity, fluid saturation and the like by analyzing the relaxation phenomenon of hydrogen atoms in a rock sample, and can effectively identify the fluid property.

Regarding the application of nuclear magnetic resonance logging parameters, the existing methods mostly directly adopt nuclear magnetic analysis parameters for relevant understanding, for example, a geological logging interpretation and evaluation method for petroleum drilling exploration, which is disclosed in chinese patent document with publication number CN101183154A and publication date of 2008, 5, 21. Some methods perform fluid property identification work after calculating original parameters, such as a method for performing reservoir evaluation by using nuclear magnetic resonance logging interpretation parameters disclosed in chinese patent literature with publication number CN101750633A and publication date of 2009, 12 and 15, and a method for performing reservoir evaluation by using a nuclear magnetic resonance logging interpretation chart disclosed in chinese patent literature with publication number CN101718878a and publication date of 2009, 12 and 15. Wherein: CN101718878A selects two parameters of oil saturation So and movable fluid saturation BVM, obtains M1 parameter by formula M1= BVM So, establishes phi-M1 explanation plate; calculating a movable oil saturation Smo parameter by using a formula Smo = BVM-Smw, obtaining an M2 parameter by using a formula M2= Smo phi, and establishing a So-M2 explanation plate; carrying out visual evaluation on the reservoir fluid category by adopting two interpretation charts; by adopting the method, the problems that the evaluated reservoir can not produce fluid and can produce fluid with certain properties can be solved, and the oil-containing condition of the reservoir and the oil production quantity can be solved. The method eliminates the factors of uncertain interpretation parameters caused by factors such as blocks, horizons, oil-containing characteristics and the like, and has universal applicability in the clastic rock oil-containing layer system.

However, in the prior art represented by the patent document with the publication number CN101718878A, two directly measured parameters in nuclear magnetic resonance or indirectly measured parameters obtained by formula calculation are mostly used to perform related interpretation work, however, in the art, the porosity, the gas saturation, the irreducible water saturation and the movable water saturation measured by the nuclear magnetic resonance logging of the natural gas reservoir are quantitative parameters of reservoir physical properties and fluid properties, and each of the parameters has very important geological significance.

Disclosure of Invention

The invention aims to provide a method for identifying fluid properties by applying a nuclear magnetic resonance quadrilateral interpretation plate aiming at the defects and shortcomings of the prior art, and solves the technical problem that the identification accuracy is still not high enough due to the fact that the prior art only adopts two directly measured parameters or indirectly measured parameters obtained after formula calculation to identify the fluid properties.

The invention is realized by adopting the following technical scheme:

a method for identifying fluid properties by applying a nuclear magnetic resonance quadrilateral interpretation plate, characterized in that:

original parameter selection: four parameters for creating an interpretation plate were chosen, respectively: are respectively、S_{Bound water}、S_{Movable water}、S_{Qi (Qi)}；

Wherein:sample porosity measured for nmr logging, unit: percent;

S_{bound water}Sample irreducible water saturation measured for nmr logging, unit: percent;

S_{movable water}Sample mobile water saturation measured for nmr logging, unit: percent;

S_{qi (Qi)}The gas saturation of a sample for nuclear magnetic resonance measurement logging is as follows: percent;

establishing a plate frame: the interpretation plate is a quadrangular plate toThe scale range of the value can be taken as a horizontal axis,S_{Qi (Qi)}The scale range of which the value can be taken is a second horizontal axis, and a horizontal coordinate is established so as toS_{Bound water}The scale range of the value can be taken as the vertical axis,S_{Movable water}The value scale range can be taken as a second longitudinal axis, a vertical coordinate is established, and the two horizontal coordinates and the two vertical coordinates are intersected and enclosed to form a quadrilateral interpretation plate;

and (3) data analysis: taking a nuclear magnetic resonance sample of a certain work area as an example, obtaining the sample、S_{Bound water}、S_{Movable water}、S_{Qi (Qi)}Are respectively marked on the horizontal axis oneThe value is set as point A; on the longitudinal axis oneS_{Bound water}Setting the value as a B point; on the second transverse axisS_{Qi (Qi)}The value is set as point C; on the second longitudinal axisS_{Movable water}The value is set as point D; connecting the AC and the BD to obtain two broken lines which intersect at a point E, wherein the point E is an analysis point of the quadrilateral interpretation plate;

establishing a nuclear magnetic resonance quadrilateral interpretation plate: obtaining analysis points of a plurality of samples of nuclear magnetic resonance of a certain work area in a data analysis step mode, dividing a fluid property area according to specific positions of the analysis points of different oil testing results in a nuclear magnetic resonance quadrilateral explanation plate, and establishing the nuclear magnetic resonance quadrilateral explanation plate;

interpretation of nuclear magnetic resonance quadrilateral plates: and calculating analysis points of the porosity, the gas saturation, the bound water and the movable water of the nuclear magnetic resonance analysis of the sample according to the data analysis steps, then placing the analysis points in a nuclear magnetic resonance quadrilateral explanation plate, and judging the fluid property in the sample according to the area where the analysis points are located.

And the scale ranges of the horizontal coordinate and the vertical coordinate control the maximum and minimum scale values of the coordinates according to the actual conditions of the work area.

The coordinates are common coordinates or logarithmic coordinates.

Compared with the prior art, the invention has the following beneficial effects:

1. compared with the prior art represented by the patent document with the publication number of CN101718878A, the method fully applies nuclear magnetic resonance logging parameters, and places four parameters of porosity, gas saturation, irreducible water saturation and movable water saturation in the same explanation plate to explain the fluid properties, so that the explanation accuracy is greatly improved compared with the prior art that two directly measured parameters in nuclear magnetic resonance or indirectly measured parameters obtained after formula calculation are adopted to carry out related explanation work.

2. The analysis point of the method is determined by the intersection line of four measurement parameters of nuclear magnetic resonance as described in data analysis, has definite geological significance, and can efficiently judge the nuclear magnetic resonance parameter characteristics of the fluid in the work area by directly knowing the analysis point.

In conclusion, the method provided by the invention is relatively comprehensively applied to the nuclear magnetic resonance logging parameters, can efficiently and conveniently identify the properties of the sample fluid, and lays a foundation for reservoir fluid property identification research.

Drawings

The invention will be described in further detail with reference to the following description taken in conjunction with the accompanying drawings and detailed description, in which:

FIG. 1 is a schematic diagram of a nuclear magnetic resonance quadrilateral interpretation plate framework setup;

FIG. 2 is a diagram of calculation of explanation parameters of an NMR quadrilateral interpretation plate;

FIG. 3 is a diagram of an explanatory diagram of a NMR quadrilateral created in a work area;

FIG. 4 is a diagram of a quadrilateral interpretation chart of NMR of a sample.

Detailed Description