CN104747170A - Magnetic positioning method for determining position of target point of drilling well - Google Patents

Abstract

The invention discloses a magnetic positioning method for determining the position of a target point of a drilling well. The method includes the following steps that two magnetic flux gates on a measurement exploring tube of a drilled well collect magnetic field data generated at the position of the target point of the drilling well, and the two magnetic flux gates have the same direction and have a fixed height difference; the magnetic field data, collected by the two magnetic flux gates, of the position of the target point serve as input of a magnetic positioning direction; the maximum magnetic field intensity, the minimum magnetic field intensity, the maximum magnetic field intensity component value and the minimum magnetic field intensity component value of the magnetic field data collected by each magnetic flux gate in each period are worked out; according to the magnetic direction relation between each magnetic flux gate and the maximum magnetic field intensity and the minimum magnetic field intensity at the position of the target point in each period, the position coordinates of the position of the target point relative to each magnetic flux gate are obtained; coordinate values of the position of the target point are determined in the combination of the fixed height between the two magnetic flux gates. The position of the target point of the drilling well can be determined accurately and uniquely, and the distance and direction between the drilling well and the drilled well are detected through the method.

Description

A kind of magnetic positioning method determining positive drilling well point of impact on target position

Technical field

The present invention relates to connected well, anti-collision range finding and the technical field of relief well, particularly in a kind of drilling process, determine the magnetic positioning method of positive drilling well point of impact on target position.

Background technology

Oil, equal energy source field, ore deposit, drilling engineering is a key link of development of resources.Such as find and confirm containing structure of oil field, obtain industry stream oil, verify certified oil gas structure containing area and reserves, obtain the geologic information about oil field and development data, finally crude oil is got ground to come etc. from underground, be difficult not come by drilling well.Along with going deep into of In Oil Field Exploration And Development work, more and more higher to the requirement of drilling engineering technology, drilling engineering has developed the various complex structural wells such as horizontal well, extended reach well, multilateral well, connected well, and complex structural well is as large in directional well input cost, positioning precision is high, have higher requirement to well logging drilling technology, as directional well, connected well require that the precision that hits is high.

Traditional well logging level only provides orientation and the inclination angle of drilling tool, the relative position parameter of drill bit and target spot can not be directly provided, be difficult to avoid error accumulation, therefore cannot meet that complex structural well drilling technology is highly reliable, high accuracy guide-localization and jamproof technical need.Although proposed the scheme calculating positive drilling well point of impact on target position in existing calculating, but because target spot rotates clockwise one week, its magnetic field intensity there will be two groups of maximum values and minimum value at this one-period, therefore the magnetic azimuth of required target spot does not have uniqueness, be difficult to the position accurately determining target spot,, easily there is the accumulation of error, cause the defects such as precision is low that hit in the position of clear and definite positive drilling well target spot.

Summary of the invention

The object of the invention is to overcome the shortcoming of prior art and deficiency, a kind of magnetic positioning method of determination positive drilling well point of impact on target position that can be accurate and unique is provided, positive drilling well and the distance between drilling well and orientation is detected by the method, the position of clear and definite positive drilling well target spot, and then instruct positive drilling well to creep into, finally reach positive drilling well and be communicated with or avoid the object that positive drilling well is communicated with drilling well with drilling well.

Object of the present invention is achieved through the following technical solutions: a kind of magnetic positioning method determining positive drilling well point of impact on target position, comprises the following steps:

On the measurement inserting tube of step 1, drilling well, two groups of fluxgates gather the magnetic field data that positive drilling well point of impact on target position produces simultaneously; On the measurement inserting tube of wherein drilling well, the orientation of two groups of fluxgates is identical and have level altitude difference;

Step 2, the target position magnetic field data that gathered by two groups of fluxgates in step 1 as the input in magnetic orientation orientation, and calculate according to the input in magnetic orientation orientation and often organize magnetic field data that fluxgate the gathers component value when the minimum value of the maximum value of each periodic magnetic field intensity, magnetic field intensity, maximum field strength time-division value and magnetic field intensity minimum value;

Step 3, according to the magnetic azimuth Relation acquisition target position often organized when fluxgate and each periodic magnetic field intensity in target position place get maximum value and minimum value relative to the position coordinates often organizing fluxgate;

Step 4, according to target position relative to the position coordinates often organizing fluxgate, in conjunction with the final position coordinate of the level altitude determination target position between two groups of fluxgates.

Preferably, the fluxgate of three components is included in described often group fluxgate, three the Component of magnetic flux doors wherein often organized are mutually orthogonal between two, orthogonal direction is respectively X-direction, Y direction and Z-direction, the left and right directions that wherein X-direction refers to above-below direction, Y direction refers to, Z-direction is fore-and-aft direction.

Further, described step 3 point of impact on target position is asked for by following formula relative to the position coordinates (x, y, z) of wherein one group of fluxgate:

Wherein Bx0, By0 and Bz0 are that the magnetic field data of this group fluxgate collection is when the minimum value BTmin of each periodic magnetic field intensity, to the component value should organizing in fluxgate the magnetic field intensity that three fluxgates gather, namely during minimum-B configuration intensity, X, Y and Z tri-magnetic field strength component value of axle; Wherein Bx1, By1 and Bz1 are that the magnetic field data of this group fluxgate collection is when the maximum value BTmax of each periodic magnetic field intensity, to the component value should organizing in fluxgate the magnetic field intensity that three fluxgates gather, namely during maximum magnetic field strength, X, Y and Z tri-magnetic field strength component value of axle; R is the distance between this group fluxgate and target spot; θ is the angle often organizing line between fluxgate and target spot and target spot direction of advance; The direction in magnetic field and the angle of target spot direction of advance when α is the maximum magnetic field strength of this group fluxgate acquisition;

Wherein

$r=\sqrt[3]{\frac{{\mathrm{\μ}}_{0}m}{4\mathrm{\π}\left|\mathrm{BT}\min \right|}};$

$\mathrm{\θ}=\frac{1}{2}\·\arccos \left(\frac{5-2\·{\left(\frac{\mathrm{BT}\max x}{\mathrm{BT}\min }\right)}^2}{3}\right);$

$\mathrm{\α}=\arcsin \left(\frac{{\left(\frac{\mathrm{BT}\max }{\mathrm{BT}\min }\right)}^2-2}{\left(\frac{\mathrm{BT}\max }{\mathrm{BT}\min }\right)}\right);$

Described step 3 point of impact on target position is asked for by following formula relative to the position coordinates (x ', y ', z ') of another group fluxgate:

Wherein the magnetic field data that gathers for this group fluxgate of Bx0 ', By0 ' and Bz0 ' is when the minimum value BTmin ' of each periodic magnetic field intensity, to the component value should organizing in fluxgate the magnetic field intensity that three fluxgates gather, namely during minimum-B configuration intensity, X, Y and Z tri-magnetic field strength component value of axle; Wherein the magnetic field data that gathers for this group fluxgate of Bx1 ', By1 ' and Bz1 ' is when the maximum value BTmax of each periodic magnetic field intensity, to the component value should organizing in fluxgate the magnetic field intensity that three fluxgates gather, namely during maximum magnetic field strength, X, Y and Z tri-magnetic field strength component value of axle; R ' is the distance between this group fluxgate and target spot; The angle that θ ' is the line between this group fluxgate and target spot and target spot direction of advance; The direction in magnetic field and the angle of target spot direction of advance during the maximum magnetic field strength that this group fluxgate of α ' obtains;

Wherein

$r^{\′}=\sqrt[3]{\frac{{\mathrm{\μ}}_{0}m}{4\mathrm{\π}\left|\mathrm{BT}\mathrm{mi}{n}^{\′}\right|}};$

${\mathrm{\θ}}^{\′}=\frac{1}{2}\·\arccos \left(\frac{5-2\·{\left(\frac{\mathrm{BT}{\max }^{\′}x}{\mathrm{BT}{\min }^{\′}}\right)}^2}{3}\right);$

${\mathrm{\α}}^{\′}=\arcsin \left(\frac{{\left(\frac{\mathrm{BT}{\max }^{\′}}{\mathrm{BT}{\min }^{\′}}\right)}^2-2}{\left(\frac{\mathrm{BT}{\max }^{\′}}{\mathrm{BT}{\min }^{\′}}\right)}\right);$

Wherein μ ₀=4 π * 10 ^-7for magnetic constant, be a fixed value, m is the magnetic moment of magnetic dipole.

Further, the unique coordinate values of described step 4 point of impact on target position obtains in the following manner:

Step 4-1, by step 3 obtain target position be updated to in following formula relative to the position coordinates often organizing fluxgate:

$\left\{\begin{array}{c}x=x^{\′}+h\\ y=y^{\′}\\ z=z^{\′}\end{array}\right.;$

Wherein h is that the level altitude of two groups of magnetic field intensities is poor;

Step 4-2, the target position meeting above-mentioned formula is defined as the final position coordinate of target spot relative to the position coordinates often organizing fluxgate.

Further, the magnetic field data in described step 1 after two groups of fluxgate collections is re-used as the input in magnetic orientation orientation after using bandpass filter to carry out filtering.

Because target spot rotates clockwise one week, its magnetic field intensity there will be two groups of maximum values and minimum value at this one-period, therefore the target position obtained in step 3 of the inventive method is relative to the position coordinates (x of wherein one group of fluxgate, y, z) there are two kinds of result (x, y, z)=(a1, b1, and (x c1), y, z)=(e1, f1, g1), the target position obtained equally relative to another group fluxgate position coordinates (x ', y ', z ') also exist two kinds of results (x ', y ', z ')=(a2, b2, c2) and (x ', y ', z ')=(e2, f2, g2), by (x, y, z)=(a1 in the step 4 of the inventive method, b1, c1) and (x, y, z) time=(e1, f1, g1) and (x ', y ', z ')=(a2, b2, c2) and (x ', y ', z ')=(e2, f2, g2) be updated to respectively in the formula of step 4-1 time, using meet the result of equation in step 4-1 corresponding as (x, y, z) and (x ', y ', z ') final result, i.e. the final position coordinate of target spot, to get the unique positions coordinate of target position.

The present invention has following advantage and effect relative to prior art:

The present invention has level altitude difference by two groups on the measurement inserting tube of drilling well and the identical fluxgate in orientation gathers the magnetic field data that positive drilling well point of impact on target position produces simultaneously, the relative position coordinates of target position and two groups of fluxgates is got according to the magnetic field data of fluxgate collection, then finally unique position coordinates of target position is determined by the level altitude difference between two groups of fluxgates, thus finally determine the target position in positive drilling well, know positive drilling well and the distance between drilling well and orientation, the position of clear and definite positive drilling well, under the scope not affecting certainty of measurement, accurately calculate the position of positive drilling well point of impact on target, for positive drilling well and drilling well theoretical foundation is provided.In petroleum logging system, realize the connection of two mouthfuls of wells by the accurate location of target spot magnetic azimuth of the present invention or avoid being communicated with, improving oil gas well yield and recovery ratio, can also relief well etc. be used as.

Accompanying drawing explanation

Fig. 1 is the inventive method is the process schematic that two wells are communicated with.

Fig. 2 is the two groups of fluxgate position relationship schematic diagrames drilling measuring inserting tube installed in the inventive method.

Fig. 3 a and 3b is the survey calculation schematic diagram of each two groups of fluxgates and target spot in the inventive method respectively.

Detailed description of the invention

Below in conjunction with embodiment and accompanying drawing, the present invention is described in further detail, but embodiments of the present invention are not limited thereto.

Embodiment

Present embodiment discloses a kind of magnetic positioning method determining positive drilling well point of impact on target position, comprise the following steps:

Step 1, as shown in Figure 1, the magnetic field data that the magnetic frock (i.e. target position) that on the measurement inserting tube 2 of drilling well 3, two groups of fluxgates gather drill bit 1 in positive drilling well 4 simultaneously produces, and use bandpass filter to carry out filtering process to the magnetic field data often organizing fluxgate collection, to carry out filtering to ambient noise.As shown in Figure 2, the two groups of fluxgates 31, the 33 measurement inserting tube 2 of drilling well 3 installed have level altitude difference h and orientation is identical; Wherein often organize in fluxgate the fluxgate including three components in the present embodiment, three the Component of magnetic flux doors often organized are mutually orthogonal between two, orthogonal direction is respectively X-direction, Y direction and Z-direction, wherein X-direction refers to above-below direction, the left and right directions that Y direction refers to, Z-direction is fore-and-aft direction.

Step 2, two groups of fluxgates in step 1 are gathered and target position magnetic field data after filtering process as the input in magnetic orientation orientation, and calculate according to the input in magnetic orientation orientation and often organize magnetic field data that fluxgate the gathers component value when the minimum value of the maximum value of each periodic magnetic field intensity, magnetic field intensity, maximum field strength time-division value and magnetic field intensity minimum value.

Step 3, according to the magnetic azimuth relation often organized when fluxgate and each periodic magnetic field intensity in target position place get maximum value and minimum value, acquisition target position is relative to the position coordinates often organizing fluxgate, and concrete acquisition process is as follows:

This step point of impact on target position is asked for by following formula relative to the position coordinates (x, y, z) of wherein one group of fluxgate:

Wherein Bx0, By0 and Bz0 are that the magnetic field data of this group fluxgate collection is when the minimum value BTmin of each periodic magnetic field intensity, to the component value should organizing in fluxgate the magnetic field intensity that three fluxgates gather, namely during minimum-B configuration intensity, X, Y and Z tri-magnetic field strength component value of axle; Wherein Bx1, By1 and Bz1 are that the magnetic field data of this group fluxgate collection is when the maximum value BTmax of each periodic magnetic field intensity, to the component value should organizing in fluxgate the magnetic field intensity that three fluxgates gather, namely during maximum magnetic field strength, X, Y and Z tri-magnetic field strength component value of axle; As shown in Figure 3 a, r refers to the distance between this group fluxgate and target spot, θ is the angle of line between this group fluxgate 31 and target spot 32 and target spot direction of advance, α be this group fluxgate 31 obtain maximum magnetic field strength time the direction in magnetic field and the angle of the direction of advance of target spot, shown in the arrow that the direction of advance of its point of impact on target 32 is set out as the target position in Fig. 3 a;

Wherein

$r=\sqrt[3]{\frac{{\mathrm{\μ}}_{0}m}{4\mathrm{\π}\left|\mathrm{BT}\min \right|}};$

$\mathrm{\θ}=\frac{1}{2}\·\arccos \left(\frac{5-2\·{\left(\frac{\mathrm{BT}\max x}{\mathrm{BT}\min }\right)}^2}{3}\right);$

$\mathrm{\α}=\arcsin \left(\frac{{\left(\frac{\mathrm{BT}\max }{\mathrm{BT}\min }\right)}^2-2}{\left(\frac{\mathrm{BT}\max }{\mathrm{BT}\min }\right)}\right);$

Wherein μ ₀=4 π * 10 ^-7for magnetic constant, be a fixed value, m is the magnetic moment of magnetic dipole.

This step point of impact on target position is asked for by following formula relative to the position coordinates (x ', y ', z ') of another group fluxgate:

Wherein the magnetic field data that gathers for this group fluxgate of Bx0 ', By0 ' and Bz0 ' is when the minimum value BTmin ' of each periodic magnetic field intensity, to the component value should organizing in fluxgate the magnetic field intensity that three fluxgates gather, namely during minimum-B configuration intensity, X, Y and Z tri-magnetic field strength component value of axle; Wherein the magnetic field data that gathers for this group fluxgate of Bx1 ', By1 ' and Bz1 ' is when the maximum value BTmax of each periodic magnetic field intensity, to the component value should organizing in fluxgate the magnetic field intensity that three fluxgates gather, namely during maximum magnetic field strength, X, Y and Z tri-magnetic field strength component value of axle; As shown in Figure 3 b, r ' is the distance between this group fluxgate and target spot; The angle that θ ' is the line between this group fluxgate 33 and target spot 32 and target spot direction of advance; The direction in magnetic field and the angle of target spot direction of advance during the maximum magnetic field strength that this group fluxgate 33 of α ' obtains, shown in the arrow that the direction of advance of its point of impact on target 32 is set out as the target position in Fig. 3 b.

Wherein

$r^{\′}=\sqrt[3]{\frac{{\mathrm{\μ}}_{0}m}{4\mathrm{\π}\left|\mathrm{BT}\mathrm{mi}{n}^{\′}\right|}};$

${\mathrm{\θ}}^{\′}=\frac{1}{2}\·\arccos \left(\frac{5-2\·{\left(\frac{\mathrm{BT}{\max }^{\′}x}{\mathrm{BT}{\min }^{\′}}\right)}^2}{3}\right);$

${\mathrm{\α}}^{\′}=\arcsin \left(\frac{{\left(\frac{\mathrm{BT}{\max }^{\′}}{\mathrm{BT}{\min }^{\′}}\right)}^2-2}{\left(\frac{\mathrm{BT}{\max }^{\′}}{\mathrm{BT}{\min }^{\′}}\right)}\right);$

Wherein μ ₀=4 π * 10 ^-7for magnetic constant, be a fixed value, m is the magnetic moment of magnetic dipole.

Step 4, according to target position relative to the position coordinates often organizing fluxgate, the coordinate value in conjunction with the level altitude determination target position between two groups of fluxgates:

Step 4-1, by step 3 obtain target position be updated to in following formula relative to the position coordinates often organizing fluxgate:

$\left\{\begin{array}{c}x=x^{\′}+h\\ y=y^{\′}\\ z=z^{\′}\end{array}\right.;$

Wherein h is that the level altitude of two groups of magnetic field intensities is poor;

Step 4-2, the target position meeting above-mentioned formula is defined as the final position coordinate of target spot relative to the position coordinates often organizing fluxgate, to determine positive drilling well and the distance between drilling well and orientation, the position of clear and definite positive drilling well, and then instruct positive drilling well to creep into.

Because target spot rotates clockwise one week, its magnetic field intensity there will be two groups of maximum values and minimum value at this one-period, namely the target position obtained in step 3 is relative to the position coordinates (x of wherein one group of fluxgate, y, z) there are two kinds of result (x, y, z)=(a1, b1, and (x c1), y, z)=(e1, f1, g1), the target position obtained equally relative to another group fluxgate position coordinates (x ', y ', z ') also exist two kinds of results (x ', y ', z ')=(a2, b2, c2) and (x ', y ', z ')=(e2, f2, g2), by (x, y, z)=(a1 in the present embodiment step 4, b1, c1) and (x, y, z) time=(e1, f1, g1) and (x ', y ', z ')=(a2, b2, c2) and (x ', y ', z ')=(e2, f2, g2) be updated to respectively in the formula of step 4-1 time, using meet the result of equation in step 4-1 corresponding as (x, y, z) and (x ', y ', z ') final result, i.e. the final position coordinate of target spot, to get the unique positions coordinate of target position.Such as (x, y, z)=(a1, b1, and (x ', y ', z ')=(a2 c1), b2, c2) when meeting in step 4-1 equation, then target position is defined as (x relative to the final position coordinate of wherein one group of fluxgate, y, z)=(a1, b1, c1), the final position coordinate organizing fluxgate relative to another is defined as (x ', y ', z ')=(a2, b2, c2).

The field signal that the present embodiment aligns dynamic rotary magnetic dipole in drilling well (i.e. magnetic frock or target position) by two groups of six fluxgates bored on borehole measurement inserting tube gathers, by the analysis of the inventive method to field signal, the position of determination magnetic dipole that just can be unique, just can determine the distance and bearing of positive drilling well target spot by the position of magnetic dipole.By the position of the clear and definite positive drilling well target spot of the present embodiment method, detect positive drilling well and the distance between drilling well and orientation, and then instruct positive drilling well to creep into, finally reach positive drilling well and be communicated with or avoid the object that positive drilling well is communicated with drilling well with drilling well, improve oil gas well yield and recovery ratio, can also relief well etc. be used as.

Above-described embodiment is the present invention's preferably embodiment; but embodiments of the present invention are not restricted to the described embodiments; change, the modification done under other any does not deviate from Spirit Essence of the present invention and principle, substitute, combine, simplify; all should be the substitute mode of equivalence, be included within protection scope of the present invention.

Claims (5)

1. determine a magnetic positioning method for positive drilling well point of impact on target position, it is characterized in that, comprise the following steps:

On the measurement inserting tube of step 1, drilling well, two groups of fluxgates gather the magnetic field data that positive drilling well point of impact on target position produces simultaneously; On the measurement inserting tube of wherein drilling well, the orientation of two groups of fluxgates is identical and have level altitude difference;

Step 2, the target position magnetic field data that gathered by two groups of fluxgates in step 1 as the input in magnetic orientation orientation, and calculate according to the input in magnetic orientation orientation and often organize magnetic field data that fluxgate the gathers component value when the minimum value of the maximum value of each periodic magnetic field intensity, magnetic field intensity, maximum field strength time-division value and magnetic field intensity minimum value;

Step 3, according to the magnetic azimuth Relation acquisition target position often organized when fluxgate and each periodic magnetic field intensity in target position place get maximum value and minimum value relative to the position coordinates often organizing fluxgate;

Step 4, according to target position relative to the position coordinates often organizing fluxgate, in conjunction with the final position coordinate of the level altitude determination target position between two groups of fluxgates.

2. the magnetic positioning method determining positive drilling well point of impact on target position according to claim 1, it is characterized in that, the fluxgate of three components is included in described often group fluxgate, three the Component of magnetic flux doors wherein often organized are mutually orthogonal between two, orthogonal direction is respectively X-direction, Y direction and Z-direction, wherein X-direction refers to above-below direction, the left and right directions that Y direction refers to, Z-direction is fore-and-aft direction.

3. the magnetic positioning method determining positive drilling well point of impact on target position according to claim 2, is characterized in that, described step 3 point of impact on target position is asked for by following formula relative to the position coordinates (x, y, z) of wherein one group of fluxgate:

Wherein Bx0, By0 and Bz0 are that the magnetic field data of this group fluxgate collection is when the minimum value BTmin of each periodic magnetic field intensity, to the component value should organizing in fluxgate the magnetic field intensity that three fluxgates gather, namely during minimum-B configuration intensity, X, Y and Z tri-magnetic field strength component value of axle; Wherein Bx1, By1 and Bz1 are that the magnetic field data of this group fluxgate collection is when the maximum value BTmax of each periodic magnetic field intensity, to the component value should organizing in fluxgate the magnetic field intensity that three fluxgates gather, namely during maximum magnetic field strength, X, Y and Z tri-magnetic field strength component value of axle; R is the distance between this group fluxgate and target spot; θ is the angle often organizing line between fluxgate and target spot and target spot direction of advance; The direction in magnetic field and the angle of target spot direction of advance when α is the maximum magnetic field strength of this group fluxgate acquisition;

Wherein

$r=\sqrt[3]{\frac{{\mathrm{\μ}}_{0}m}{4\mathrm{\π}\left|\mathrm{BT}\min \right|}};$

$\mathrm{\θ}=\frac{1}{2}\·\arccos \left(\frac{5-2\·{\left(\frac{\mathrm{BT}\max x}{\mathrm{BT}\min }\right)}^2}{3}\right);$

$\mathrm{\α}=\arcsin \left(\frac{{\left(\frac{\mathrm{BT}\max }{\mathrm{BT}\min }\right)}^2-2}{\left(\frac{\mathrm{BT}\max }{\mathrm{BT}\min }\right)}\right);$

Described step 3 point of impact on target position is asked for by following formula relative to the position coordinates (x ', y ', z ') of another group fluxgate:

Wherein the magnetic field data that gathers for this group fluxgate of Bx0 ', By0 ' and Bz0 ' is when the minimum value BTmin ' of each periodic magnetic field intensity, to the component value should organizing in fluxgate the magnetic field intensity that three fluxgates gather, namely during minimum-B configuration intensity, X, Y and Z tri-magnetic field strength component value of axle; Wherein the magnetic field data that gathers for this group fluxgate of Bx1 ', By1 ' and Bz1 ' is when the maximum value BTmax of each periodic magnetic field intensity, to the component value should organizing in fluxgate the magnetic field intensity that three fluxgates gather, namely during maximum magnetic field strength, X, Y and Z tri-magnetic field strength component value of axle; R ' is the distance between this group fluxgate and target spot; The angle that θ ' is the line between this group fluxgate and target spot and target spot direction of advance; The direction in magnetic field and the angle of target spot direction of advance during the maximum magnetic field strength that this group fluxgate of α ' obtains;

Wherein

$r^{\′}=\sqrt[3]{\frac{{\mathrm{\μ}}_{0}m}{4\mathrm{\π}\left|\mathrm{BT}{\min }^{\′}\right|}};$

${\mathrm{\θ}}^{\′}=\frac{1}{2}\·\arccos \left(\frac{5-2\·{\left(\frac{\mathrm{BT}{\max }^{\′}x}{\mathrm{BT}{\min }^{\′}}\right)}^2}{3}\right);$

${\mathrm{\α}}^{\′}=\arcsin \left(\frac{{\left(\frac{\mathrm{BT}{\max }^{\′}}{\mathrm{BT}{\min }^{\′}}\right)}^2-2}{\left(\frac{\mathrm{BT}{\max }^{\′}}{\mathrm{BT}{\min }^{\′}}\right)}\right);$

Wherein μ ₀=4 π * 10 ^-7for magnetic constant, be a fixed value, m is the magnetic moment of magnetic dipole.

4. the magnetic positioning method determining positive drilling well point of impact on target position according to claim 3, is characterized in that, the unique coordinate values of described step 4 point of impact on target position obtains in the following manner:

Step 4-1, by step 3 obtain target position be updated to in following formula relative to the position coordinates often organizing fluxgate:

$\left\{\begin{array}{c}x=x^{\′}+h\\ y=y^{\′}\\ z=z^{\′}\end{array}\right.;$

Wherein h is that the level altitude of two groups of magnetic field intensities is poor;

Step 4-2, the target position meeting above-mentioned formula is defined as the final position coordinate of target spot relative to the position coordinates often organizing fluxgate.

5. the magnetic positioning method determining positive drilling well point of impact on target position according to claim 3, is characterized in that, the magnetic field data in described step 1 after two groups of fluxgate collections is re-used as the input in magnetic orientation orientation after using bandpass filter to carry out filtering.