CN101086534A - Demodulator probe secondary localization method - Google Patents

Abstract

The demodulator probe secondary positioning method of offshore oil earthquake starts with the looking for a demodulator probe location. Calibration of the demodulator probe based on the data of the location's data, if it is pulled in the best position, the coordinate of the point is the actual coordinate of the demodulator probe. It improves the existing speed over 7 times, with positioning precision significantly improved. It can reduce working load of relevant personnel, saving a lot of working time.

Description

Demodulator probe secondary localization method

Technical field

The present invention relates to the petroleum geology exploration operating technique, is a kind of demodulator probe secondary localization method in the petroleum seismic of neritic area, beach.

Background technology

In neritic area, beach oil geology seismic prospecting construction, need the wave detector sinking be arrived the seabed with ship, generally by the terrestrial coordinate of satnav (GPS) equipment records geophone station, this process is the one-time positioning of geophone station usually during sinking.If the position of geophone station is accurate, after the road collection data of geophone station were done linear normal moveout correction in the information of seismological observation collection, the first arrival ski-jump should be evened up (as Fig. 1).When seismological observation is gathered accurately the geophone station position be the necessary condition that data is prospected in high-quality earthquake, be the condition that obtains high-quality stacked section and end result section.

In actual observation, because the enforcement state of ship, sinking operation and stormy waves, morning and evening tides, influences such as trench can cause the wave detector offset, make that the first arrival ski-jump can not be evened up (as Fig. 2) after the linear normal moveout correction, like this, the reflected signal that can not guarantee same reflection horizon when road collection data are done overlap-add procedure reduces the resolution of stacked section with superimposed, has a strong impact on the quality of final processing achievement section.So need carry out second positioning to the geophone station position.

Demodulator probe secondary is positioned with two kinds of methods at present: radiocoustic position finding method and primary wave localization method, " petroleum exploration " 2003 the 4th phases disclose " the round crossing localization method " of employing, principle such as Fig. 3.R is the physical location of the geophone station that will ask for, and sonar is tied up on wave detector during radiocoustic position finding; S1 during the primary wave location, S2, S3 are the sp locations; During radiocoustic position finding, S1, S2, S3 are the positions of radiocoustic position finding ship.

With S1, S2 is the center of circle, with speed (V1 respectively, V2) multiply by the time (T1 T2) is that radius draws circle, when V1*T1+V2*T2 greater than the absolute value of S1S2 and V1*T1-V2*T2 during less than S1S2, two circles have two intersection points, and the point that has in two intersection points is exactly the physical location of geophone station; Equally, respectively with S1, S3 is the center of circle, (V1 multiply by the time V3) that (T1 T3) is that radius draws circle with speed, when V1*T1+V3*T3 greater than the absolute value of S1S3 and V1*T1-V3*T3 during less than S1S3, two circles have two intersection points, the point that has in two intersection points is exactly the physical location of geophone station; Work as S1, S2, the position of S3 is accurate, and V1, V2, V3, T1, T2, T3 be accurately the time, and S1 and S2 intersect, and S1 and S3 are crossing to have a public intersection point, and this public intersection point is exactly the physical location of geophone station.

In addition, when the absolute value that equals S1S2 or V1*T1-V2*T2 as V1*T1+V2*T2 equals S1S2, with S1, S2 is the center of circle, and (V1 V2) multiply by the time (T1 with speed, T2) draw circle for radius, two circles will have an intersection point, and this intersection point is exactly the physical location of geophone station.Wherein: when doing the primary wave location, speed V1, V2, V3 are the comprehensive speeds of seismic wave, and time T 1, T2, T3 are the first break times of seismic wave; When doing the sonar location, speed V1, V2, V3 are the velocity of propagation of sound wave in water, and time T 1, T2, T3 are the single way time of sound wave at water transmission.

This method in actual applications, S1, S2, the position of S3 and V1, V2, V3, T1, T2, T3 is not an absolutely accurate, so, three circles generally do not have public intersection point when intersecting in twos, can not be by the position of intersecting the second positioning point of determining geophone station of 3 circles, which also to finish: 1) all definite circles in the sp location relevant with this geophone station (radiocoustic position finding ship position) are carried out computing, will judge that simultaneously which circle has intersection point, the no intersection point of circle by following two steps, and will consider that two circles intersect the time, the relative position of two circles by the computing of intersecting in twos, obtains a plurality of intersection points (point looses) to influence of the error of calculation or the like; 2) a plurality of intersection points (point looses) that obtain being done the computing of asking " center of gravity ", should " center of gravity " position be exactly the position of the second positioning point of this geophone station.

As seen, the operand of existing " round crossing localization method " is big, and the man power and material who takies is a lot, and simultaneously, when the computing of location, the relative position of two circles can exert an influence to bearing accuracy, makes it to be difficult to obtain higher second positioning.

Summary of the invention

The object of the invention provides a kind of demodulator probe secondary localization method that can improve locating speed and precision effectively.

The invention provides following technical scheme, adopt following steps:

1) adopts conventional method that acquiring seismic data is observed in the construction area, carry out the first break time of shot gather data and pick up, obtain the first break time T of each shot point to geophone station;

2) adopt conventional method to set up the velocity field of construction area, obtain the seismic wave propagation speed V of shot point to geophone station;

3) the one-time positioning point position with geophone station is the center, and area dividing is on every side become grid, the length of side 2*DS of net region, and the grid number on every limit is: m=2*int (DS/d), d are the interval of grid, DS is the deviation range of geophone station;

4) with a grid node position as the geophone station position, the road collection data of this geophone station are done the line school, and calculate first arrival and even up effect;

With a grid node position XX[j], YY[k] as the geophone station position, calculate the linear dynamic correction value in each road and the difference of this road first break time $\frac{\sqrt{{(X\left[i\right]-\mathrm{XX}\left[j\right])}^2+{(Y\left[i\right]-\mathrm{YY}\left[k\right])}^2}}{V\left[i\right]}-T\left[i\right]$ , after this difference was exactly linear normal moveout correction, the first arrival ski-jump in this road departed from the deviation of 0 datum line;

In the formula: j=1,2 ... m+1; K=1,2 ... m+1 represents (m+1) * (m+1) individual grid node is calculated;

$\sqrt{{(X\left[i\right]-\mathrm{XX}\left[j\right])}^2+{(Y\left[i\right]-\mathrm{YY}\left[k\right])}^2}$ Be i shot point (X[i], Y[i]) to the distance of this geophone station assumed position (XX[j], YY[k]);

$\frac{\sqrt{{(X\left[i\right]-\mathrm{XX}\left[j\right])}^2+{(Y\left[i\right]-\mathrm{YY}\left[k\right])}^2}}{V\left[i\right]}$ Being seismic wave propagates into the used time of this geophone station desired location (XX[j], YY[k]) from i shot point (X[i], Y[i]);

T[i] to be seismic wave propagate into used time of this geophone station physical location, i.e. first break time from i shot point (X[i], Y[i]);

Effect SDT[j is evened up in first arrival] [k] be the absolute value sum that the first arrival ski-jump departs from the deviation of 0 datum line after the linear normal moveout correction in each road,

$\mathrm{SDT}\left[j\right]\left[k\right]=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}(\frac{\sqrt{{(X\left[i\right]-\mathrm{XX}\left[j\right])}^2+{(Y\left[i\right]-\mathrm{YY}\left[k\right])}^2}}{V\left[i\right]}-T\left[i\right]);$

Wherein: i=1,2 ... n represents all data tracks of this geophone station are calculated;

5) obtain first arrival and even up effect S DT[j] [k] (j=1,2 ... m+1; K=1,2 ... m+1) a S DT[j0 of minimum in] [k0], its XX[j0], YY[k0] be the second positioning point position coordinates of geophone station.

The invention provides following technical scheme, in the described step 3), the interval d bearing accuracy as requested of grid is determined; The deviation range DS of geophone station determines according to the bearing accuracy of one-time positioning point.

Second positioning repeating step 3 to all geophone stations of construction area) to 5) step.

More traditional " the round crossing localization method " of speed that the present invention does the second positioning computing improved more than 7 times, bearing accuracy also is significantly improved simultaneously. for example: at the about big gun more than 3300 of a bunch, have in the construction of 960 geophone stations, carry out the second positioning computing with this method and need 60 minutes, need 420 minutes and utilize traditional " round crossing localization method " to do the location computing, alleviate related personnel's working strength, saved a large amount of working times.

Description of drawings

Fig. 1 for the geophone station position when accurate behind the line school first arrival even up design sketch;

Fig. 2 for the geophone station position when inaccurate behind the line school first arrival even up design sketch;

Fig. 3 is round crossing localization method schematic diagram.

Embodiment

The present invention is based on the demodulator probe secondary localization method that the first arrival of line school is evened up, find the position of a geophone station earlier, if after with the data of this location point the road collection data of this geophone station being done linear normal moveout correction, it is best that effect is evened up in first arrival, and then the coordinate of this point is exactly the actual position coordinate of geophone station.

Concrete steps are as follows:

1) adopts conventional method that acquiring seismic data is observed in the construction area, carry out the first break time of shot gather data and pick up, obtain the first break time T of each shot point to geophone station;

2) adopt conventional method to set up the velocity field of construction area, obtain the seismic wave propagation speed V of shot point to geophone station;

3) the one-time positioning point position with geophone station is the center, and area dividing is on every side become grid, the length of side 2*DS of net region, and the grid number on every limit is: m=2*int (DS/d), d are the interval of grid, DS is the deviation range of geophone station;

4). with a grid node hypothesis on location is the geophone station position, and the road collection data of this geophone station are done the line school, and calculates first arrival and even up effect;

With each grid node position XX[j], YY[k] be assumed to be the geophone station position, calculate the linear dynamic correction value in each road and the difference of this road first break time $(\frac{\sqrt{{(X\left[i\right]-\mathrm{XX}\left[j\right])}^2+{(Y\left[i\right]-\mathrm{YY}\left[k\right])}^2}}{V\left[i\right]}-T\left[i\right]),$ After this difference was exactly linear normal moveout correction, the first arrival ski-jump in this road departed from the deviation of 0 datum line, and the absolute value sum of the deviate in all roads can represent that first arrival evens up effect SDT[j] [k].

SDT[j] [k] be the absolute value sum that the first arrival ski-jump departs from the deviation of 0 datum line after the linear normal moveout correction in each road.This value is more little, and more near 0, it is good more to illustrate that effect is evened up in first arrival.

$\mathrm{SDT}\left[j\right]\left[k\right]=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}(\frac{\sqrt{{(X\left[i\right]-\mathrm{XX}\left[j\right])}^2+{(Y\left[i\right]-\mathrm{YY}\left[k\right])}^2}}{V\left[i\right]}-T\left[i\right]);......\left(1\right)$

In the expression formula (1):

SDT[j] [k] middle j=1,2 ... m+1; K=1,2 ... m+1 represents (m+1) * (m+1) individual grid node is calculated; $\sqrt{{(X\left[i\right]-\mathrm{XX}\left[j\right])}^2+{(Y\left[i\right]-\mathrm{YY}\left[k\right])}^2}$ Be i shot point (X[i], Y[i]) to the distance of this geophone station assumed position (XX[j], YY[k]); $\frac{\sqrt{{(X\left[i\right]-\mathrm{XX}\left[j\right])}^2+{(Y\left[i\right]-\mathrm{YY}\left[k\right])}^2}}{V\left[i\right]}$ Being seismic wave propagates into used time of this geophone station assumed position (XX[j], YY[k]), promptly linear dynamic correction value from i shot point (X[i], Y[i]);

T[i] to be seismic wave propagate into used time of this geophone station physical location, i.e. first break time from i shot point (X[i], Y[i]);

T[i] 5) first arrival of alternative line school evens up effect SDT[j] [k] (j=1,2 ... m+1; K=1,2 ... m+1), find minimum value wherein, the position coordinates of the grid node of this minimum value correspondence is exactly the demodulator probe secondary elements of a fix.

Find SDT[j] [k] (j=1,2 ... m+1; K=1,2 ... m+1) SDTmin of minimum in;

SDTmin＝SDT[1][1]；

SDTmin＝min(SDTmin，SDT[j][k])…………(2)

In the expression formula (2): j=1,2 ... m+1; K=1,2 ... m+1

Suppose: work as j=j0, during k=k0, SDT[j] [k] be worth minimum, so, XX[j0], YY[k0] be exactly the second positioning point position coordinates of geophone station.

6) all geophone stations are repeated 3,4,5 steps, finish the second positioning work of all geophone stations.

In certain shallow sea prospection project, a bunch has 3300 big guns, has 960 geophone stations, utilizes method of the present invention as follows to the process that geophone station carries out second positioning:

1. 3300 big guns are carried out first break time and pick up, obtained the first break time of each shot point to geophone station;

2. set up the velocity field of construction area, obtain the seismic wave propagation speed of shot point to geophone station;

3. the position area dividing on every side of once putting with a geophone station becomes grid;

As: this geophone station has received the data of n shot point, and n the data track of acceptance point altogether promptly arranged;

The coordinate of each shot point is: X[i], Y[i] (i=1,2 ... n);

Each shot point to the first break time of geophone station is: T[i] (i=1,2 ... n);

Each shot point to the seismic wave propagation speed of geophone station is: V[i] (i=1,2 ... n);

The coordinate of the one-time positioning point of this geophone station is: (X0, Y0);

The positioning error that requires is 1m;

The deviation range of geophone station is 50m, and promptly physical location and deviation once are in 50m, and (X0 is that grid is divided at the center Y0) with the one-time positioning point of this geophone station; The scope of net region is the Probability Area at the physical location place of this geophone station, so, the length of side 100m of net region, grid be spaced apart 1, so the grid number on every limit is: 100; Obtain the individual grid node of (101) * (101), XX[j], YY[k] (j=1,2 ... 101; K=1,2 ... 101);

4. be the geophone station position with a grid node hypothesis on location, the road collection data of this geophone station are done the line school and calculated first arrival and even up effect;

With each grid node position XX[j], YY[k] be assumed to be the geophone station position, road collection data are done the line school, obtain first arrival and even up effect SDT[j] [k], SDT[j] [k] be the absolute value sum that the first arrival ski-jump departs from the deviation of 0 datum line after the linear normal moveout correction in each road.This value is more little, and more near 0, it is good more to illustrate that effect is evened up in first arrival.

$\mathrm{SDT}\left[j\right]\left[k\right]=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}(\frac{\sqrt{{(X\left[i\right]-\mathrm{XX}\left[j\right])}^2+{(Y\left[i\right]-\mathrm{YY}\left[k\right])}^2}}{V\left[i\right]}-T\left[i\right]);$

In the expression formula: j=1,2 ... 101; K=1,2 ... 101 expressions are calculated 101 * 101 grid nodes;

5. effect SDT[j is evened up in the first arrival of alternative line school] [k] (j=1,2 ... 101; K=1,2 ... 101), find minimum value wherein, the position coordinates of the grid node of this minimum value correspondence is exactly the demodulator probe secondary elements of a fix.

Find SDT[j] [k] (j=1,2 ... 101; K=1,2 ... 101) SDTmin of minimum in;

SDTmin＝SDT[1][1]；

SDTmin＝min(SDTmin，SDT[j][k])

In the expression formula: j=1,2 ... 101; K=1,2 ... 101

Suppose: work as j=j0, during k=k0, SDT[j] [k] be worth minimum, so, XX[j0], YY[k0] be exactly the second positioning point position coordinates of geophone station.

Step 3,4,5 has been finished the second positioning computing of a geophone station.

6. all geophone stations are repeated 3,4,5 steps, finish the second positioning work of all geophone stations.

Claims (3)

1, a kind of demodulator probe secondary localization method is characterized in that adopting following steps:

1) adopts conventional method that acquiring seismic data is observed in the construction area, carry out the first break time of shot gather data and pick up, obtain the first break time T of each shot point to geophone station;

2) adopt conventional method to set up the velocity field of construction area, obtain the seismic wave propagation speed V of shot point to geophone station;

3) the one-time positioning point position with geophone station is the center, and area dividing is on every side become grid, the length of side 2*DS of net region, and the grid number on every limit is: m=2*int (DS/d), d are the interval of grid, DS is the deviation range of geophone station;

4) with a grid node position as the geophone station position, the road collection data of this geophone station are done the line school, and calculate first arrival and even up effect;

With a grid node position XX[j], YY[k] as the geophone station position, calculate the linear dynamic correction value in each road and the difference of this road first break time $\frac{\sqrt{{\left(X\right[i]-\mathrm{XX}[j\left]\right)}^2+{\left(Y\right[i]-\mathrm{YY}[k\left]\right)}^2}}{V\left[i\right]}-T\left[i\right]$ After this difference was exactly linear normal moveout correction, the first arrival ski-jump in this road departed from the deviation of 0 datum line;

In the formula: j=1,2 ... m+1; K=1,2 ... m+1 represents (m+1) * (m+1) individual grid node is calculated;

$\sqrt{{\left(X\right[i]-\mathrm{XX}[j\left]\right)}^2+{\left(Y\right[i]-\mathrm{YY}[k\left]\right)}^2}$ Be i shot point (X[i], Y[i]) to the distance of this geophone station assumed position (XX[j], YY[k]);

$\frac{\sqrt{{\left(X\right[i]-\mathrm{XX}[j\left]\right)}^2+{\left(Y\right[i]-\mathrm{YY}[k\left]\right)}^2}}{V\left[i\right]}$ Being seismic wave propagates into the used time of this geophone station desired location (XX[j], YY[k]) from i shot point (X[i], Y[i]);

T[i] to be seismic wave propagate into used time of this geophone station physical location, i.e. first break time from i shot point (X[i], Y[i]);

Effect SDT[j is evened up in first arrival] [k] be the absolute value sum that the first arrival ski-jump departs from the deviation of 0 datum line after the linear normal moveout correction in each road, $\mathrm{SDT}\left[j\right]\left[k\right]=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}(\frac{\sqrt{{\left(X\right[i]-\mathrm{XX}[j\left]\right)}^2+{\left(Y\right[i]-\mathrm{YY}[k\left]\right)}^2}}{V\left[i\right]}-T\left[i\right]);$

Wherein: i=1,2 ... n represents all data tracks of this geophone station are calculated;

5) obtain first arrival and even up effect SDT[j] [k] (j=1,2 ... m+1; K=1,2 ... m+1) SDT[j0 of minimum in] [k0], its XX[j0], YY[k0] be the second positioning point position coordinates of geophone station.

2, demodulator probe secondary localization method according to claim 1 is characterized in that: in the step 3), the interval d of grid determines according to the bearing accuracy that known exploration requires; The deviation range DS of geophone station determines according to the bearing accuracy of known one-time positioning point.

3, demodulator probe secondary localization method according to claim 1 is characterized in that: repeating step 3) to 5) step finishes the second positioning of all geophone stations of construction area.

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