阅读说明：本技术 一种六分量地震数据及绝对重力测量仪、测量方法 (Six-component seismic data and absolute gravity measuring instrument and measuring method ) 是由 陈彦钧 操玉文 曾卫益 朱兰鑫 李正斌 于 2020-12-07 设计创作，主要内容包括：本发明公开了一种六分量地震数据及绝对重力测量仪、测量方法。本方法为：1)将固定框架放置在待测位置；其中三个旋转地震计分别固定在该固定框架三个相互垂直的侧壁上,三个平移地震计分别固定在该固定框架三个相互垂直的侧壁上；2)将三个旋转地震计分别测量得到的三个正交的旋转分量θ-x、θ-y、θ-z发送给数据处理单元；将三个平移地震计分别测量得到的三个正交的平移分量d-x、d-y、d-z发送给数据处理单元；3)数据处理单元根据公式计算得到对重力加速度g；其中s＝j2πf,f为观测频率。本发明可实现绝对重力和六分量地震数据的同时获取,大大提升了数据采集效率,为勘探提供低成本、高效率方案。(The invention discloses a six-component seismic data and absolute gravity measuring instrument and a measuring method. The method comprises the following steps: 1) placing the fixed frame at a position to be measured; the three rotating seismometers are respectively fixed on three mutually vertical side walls of the fixed frame, and the three translation seismometers are respectively fixed on three mutually vertical side walls of the fixed frame; 2) three orthogonal rotation components theta obtained by respectively measuring three rotation seismic scores x 、θ y 、θ z Sending the data to a data processing unit; three orthogonal translation components d obtained by respectively measuring three translation seismic scores x 、d y 、d z Sending the data to a data processing unit; 3) the data processing unit is based on formula Calculating to obtain a gravity acceleration g; where s is j2 pi f, and f is the observation frequency. The invention can realize the simultaneous acquisition of absolute gravity and six-component seismic data, thereby greatly improving the dataThe acquisition efficiency provides a low-cost and high-efficiency scheme for exploration.)

1. A six-component seismic data and absolute gravity measuring instrument is characterized by comprising a fixed frame, three angular velocity type rotation seismometers and three velocity type translation seismometers; wherein

Three angular velocity type rotation seismometers are respectively fixed on three mutually vertical side walls of the fixed frame and are respectively used for measuring three orthogonal rotation components omega in six-component seismic data_x、ω_y、ω_zAnd sends it to the data processing unit;

three velocity type translation seismometers are respectively fixed on three mutually vertical side walls of the fixed frame and are respectively used for measuring three orthogonal translation components v in six-component seismic data_x、v_y、v_zAnd sends it to the data processing unit;

a data processing unit for processing the data according to a formulaCalculating to obtain gravity acceleration g; where s is j2 pi f, and f is the observation frequency.

2. A method for measuring six-component seismic data and absolute gravity comprises the following steps:

1) placing the fixed frame at a position to be measured; three angular velocity type rotation seismometers are respectively fixed on three mutually vertical side walls of the fixed frame, and three velocity type translation seismometers are respectively fixed on three mutually vertical side walls of the fixed frame;

2) three orthogonal rotation components omega obtained by respectively measuring three angular velocity type rotation seismographs_x、ω_y、ω_zSending the data to a data processing unit; three orthogonal translation components v obtained by respectively measuring three velocity type translation seismographs_x、v_y、v_zSending the data to a data processing unit;

3) the data processing unit is based on formulaCalculating to obtain a gravity acceleration g; where s is j2 pi f, and f is the observation frequency.

3. A six-component seismic data and absolute gravity measuring instrument is characterized by comprising a fixed frame, three rotating seismometers and three translation seismometers; wherein

Three rotational seismometers are respectively fixed on three mutually vertical side walls of the fixed frame and are respectively used for measuring three orthogonal rotational components theta in six-component seismic data_x、θ_y、θ_zAnd sends it to the data processing unit;

three translation seismometers are respectively fixed on three mutually vertical side walls of the fixed frame and are respectively used for measuring three orthogonal translation components d in six-component seismic data_x、d_y、d_zAnd sends it to the data processing unit;

a data processing unit for processing the data according to a formulaCalculating to obtain gravity acceleration g; where s is j2 pi f, and f is the observation frequency.

4. The six-component seismic data and absolute gravity survey meter of claim 3 wherein the rotational seismometer is an angular-type sensor, or an acceleration-type sensor and an integral computation module; the translation seismometer is a displacement type sensor or an angular acceleration type sensor and an integral operation module.

5. A method for measuring six-component seismic data and absolute gravity comprises the following steps:

1) placing the fixed frame at a position to be measured; the three rotating seismometers are respectively fixed on three mutually vertical side walls of the fixed frame, and the three translation seismometers are respectively fixed on three mutually vertical side walls of the fixed frame;

2) three orthogonal rotation components theta obtained by respectively measuring three rotation seismic scores_x、θ_y、θ_zSending the data to a data processing unit; three orthogonal translation components d obtained by respectively measuring three translation seismic scores_x、d_y、d_zSending the data to a data processing unit;

3) the data processing unit is based on formulaCalculating to obtain a gravity acceleration g; where s is j2 pi f, and f is the observation frequency.

6. The method of claim 5, wherein the rotating seismometer is an angular-type sensor, or an acceleration-type sensor and an integral operation module; the translation seismometer is a displacement type sensor or an angular acceleration type sensor and an integral operation module.

Technical Field

The invention relates to a six-component seismic data and absolute gravity measuring instrument and a measuring method, which can be used in the geophysical data observation field, such as the field of engineering and scientific research, including geophysical seismic wave field and gravity field observation, gravitational constant measurement, mineral resource development, geothermal resource development, geophysical exploration, earthquake and geological disaster early warning, and the like.

Background

Human detection of the earth underground space requires the use of geophysical data observation instruments, such as gravimeters (including absolute gravimeters and relative gravimeters; gravity refers to acceleration of gravity, the same applies below), magnetometers, resistivity meters, magnetotelluric instruments, seismographs, gamma meters, and the like, which can respectively detect different physical properties, thereby detecting underground information at different angles. However, due to the complexity of the geophysical structure, different geological structures sometimes acquire substantially the same geophysical observation data, which makes it difficult to obtain accurately representable subsurface structures during the interpretation of the geophysical data, which is the ambiguity of the geophysical problem.

Under the theoretical bottleneck of the multi-solution of the geophysical problem, the detection accuracy can be effectively improved and the adverse effect of the multi-solution can be reduced by adopting various physical observation data. The most common type of geophysical data at present is seismic wave data, which has the advantage of higher vertical resolution, but is affected by seismic blind areas, and has a poor effect on shallow exploration. The gravity exploration has the advantage of high transverse resolution, and can effectively improve the disadvantage of poor detection effect of shallow seismic parts and increase the sensitivity to local density abnormality by combining with seismic data.

The current method for acquiring multi-type geophysical data is to use multiple instruments to perform respective observation and then summarize. On one hand, the field working time is increased, and the exploration efficiency is reduced; on the other hand, different physical property observation instruments with different use principles can cause system errors and consistency errors due to different use methods, and the data precision is reduced.

Disclosure of Invention

Aiming at the current situation that only single physical data can be observed by a geophysical instrument at present, the invention provides an instrument and a measurement method which can be used for measuring six-component seismic data and absolute gravity. The acquisition of six-component seismic data and gravity data is integrated in the same instrument, so that the simultaneous acquisition of three components of absolute gravity, seismic translation and rotation can be realized, the data acquisition efficiency is greatly improved, and a low-cost and high-efficiency scheme is provided for geophysical combined exploration; on the other hand, the system error and the consistency error generated by the instrument can be reduced, and the quality of geophysical exploration data is improved. In addition, the simultaneous acquisition of seismic and gravity data can enhance the sensitivity of current seismic exploration to shallow detection and to density anomalies.

Figure 1 shows the principle of six-component seismic and absolute gravity measurements. The rotation seismometer and the translation seismometer with the sensitive axes in the x direction, the y direction and the z direction are respectively fixed on a frame, when the whole frame is placed at a point to be measured, the rotation seismometer in the x direction, the y direction and the z direction can measure the rotation seismic waves in the corresponding directions, and the translation seismometer in the x direction, the y direction and the z direction can measure the translation seismic waves in the corresponding directions, so that the acquisition work of the six-component seismic waves is completed.

For the translation seismometer in the x and y directions, the unit acceleration shock response H_x、H_yAs shown in formula (1):

where s is the complex frequency of the Laplace transform, k_x、k_yEquivalent spring damping of the translation seismometer in the x and y directions, respectively, c_x、c_yEquivalent viscous damping coefficient m of translation seismometer in x and y directions respectively_x、m_yEquivalent mass of the translation seismometer in the x direction and the y direction respectively.

Because the point to be measured has the translational motion and the rotational motion generated by natural earthquake and man-made noise, the point to be measured has the translational motion in the three directions of x, y and z, and the magnitudes are d respectively_x、d_y、d_z(all are displacement dimensions),the rotation motion exists in the three directions of x, y and z, and the angle is theta_x、θ_y、θ_z(all in an angular dimension), the equivalent mass of the x, y direction translational seismometer is the response delta generated by the translational motion and the rotational motion_x、δ_yComprises the following steps:

wherein g is the acceleration of gravity.

From formula (2):

where s is j2 pi f, f is the observation frequency, d_x、d_y、θ_x、θ_yAre all functions of f.

The translational seismometer is designed to be velocity type (namely the amplitude for acquiring three-component translational seismic data is proportional to the amplitude of the translational seismic wave velocity dimension) and the rotational seismometer is designed to be angular velocity type (namely the amplitude for acquiring three-component rotational seismic data is proportional to the amplitude of the rotational seismic wave angular velocity dimension) without loss of generality, and the velocity data measured by the translational seismometer with the sensitive axes of x, y and z in three directions are respectively v_x、v_y、v_zThe angular velocity data measured by the rotating seismometer with the sensitive axes in the x, y and z directions are respectively omega_x、ω_y、ω_z. The correlation properties according to equation (3) and laplace transform can be found:

as can be seen from equation (4), based on the six-component seismic data and the absolute gravimeter shown in FIG. 1, not only three orthogonal translational components (e.g., v) of the six-component seismic waves can be directly acquired_x、v_y、v_z) And three orthogonal rotational components (e.g.ω_x、ω_y、ω_z) The absolute gravity acceleration g can be calculated by the formula (4), so that the earthquake and the absolute gravity can be simultaneously observed.

An embodiment of the present invention is shown in the block diagram of fig. 2. Fixing a velocity type translation seismometer with the sensitive axes in the directions of x, y and z and an angular velocity type rotation seismometer with the sensitive axes in the directions of x, y and z on a fixed frame shown in the attached drawing 1, wherein output data is seismic translation three-component data v_x、v_y、v_zAnd rotational three-component data omega_x、ω_y、ω_z. Taking translational seismometer data v with sensitive axis in x direction_xAnd rotational seismometer data omega with y-direction sensitive axis_yOr translational seismometer data v with y-direction sensitive axis_yAnd rotational seismometer data omega with sensitive axis in x direction_xAnd the absolute gravity can be obtained in the data processing unit according to the formula (4), so that the simultaneous measurement of the six-component earthquake and the absolute gravity is realized.

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

the invention provides a measuring instrument and a measuring method capable of simultaneously observing six-component seismic data and absolute gravity, which firstly put forward that the six-component seismic data are integrated in the same instrument, and the six components are utilized to measure the absolute gravity, thereby improving the geophysical data acquisition efficiency and providing a low-cost and high-efficiency data acquisition instrument and measuring means for geophysical combined exploration; the data acquisition of earthquake and gravity is integrated in the same instrument, so that the system error and consistency error generated by the instrument can be reduced, and the quality of geophysical exploration data is improved; the simultaneous acquisition of seismic and gravity data can enhance the sensitivity of seismic exploration commonly used at present to shallow detection and density anomalies.

Drawings

FIG. 1 illustrates six-component seismic data and the principle of absolute gravity measurement.

FIG. 2 is a diagram of a six-component seismic data and absolute gravity measurement method.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings.

The principle of six-component earthquake and absolute gravity measurement is shown in fig. 1, a rotating seismometer and a translating seismometer with the sensitive axes of x, y and z respectively are fixed on a frame shown in the figure, and the fixed frame is placed at a point to be measured. The six-component earthquake and absolute gravity measurement method is shown in the attached figure 2, three translation seismometers measure earthquake translation three-component data, three rotation seismometers measure earthquake rotation three-component data, and absolute gravity can be resolved by using the translation seismometers and the rotation seismometers which are orthogonal to each other in the x direction and the y direction and inputting the data processing unit into the rotation seismometers.

Specifically, a velocity type translation seismometer with the sensitive axes in the x direction, the y direction and the z direction and an angular velocity type rotation seismometer with the sensitive axes in the x direction, the y direction and the z direction are fixed at corresponding positions of a fixed frame shown in the attached drawing 1. The rotating seismometer can use a fiber-optic gyroscope, and the translation seismometer can use a force balance type velocity seismometer. The fiber-optic gyroscope with the sensitive axes in the x, y and z directions can measure the rotating seismic waves in the corresponding directions, the force balance type velocity seismometer with the sensitive axes in the x, y and z directions can measure the translating seismic waves in the corresponding directions, and the six-component seismic waves are measured by combining the rotating seismic waves and the translating seismic waves. The absolute gravity can be obtained by using the formula (4) through the x-direction optical fiber gyro and the y-direction force balance type velocity seismometer or the y-direction optical fiber gyro and the x-direction force balance type velocity seismometer, so that the simultaneous measurement of the six-component seismic waves and the absolute gravity is realized.

The translational seismic waves and the rotational seismic waves related by the scheme can be natural seismic waves, can also be seismic waves generated by human activities, and can also be seismic waves excited by artificial equipment (such as explosive sources, hammering sources, source guns, electric spark and air gun sources, controllable sources and the like).

For the above implementation method, the velocity type translational seismometer can be replaced by an acceleration type sensor (such as an accelerometer) for obtaining a velocity type signal through integration, and the angular velocity type rotation sensor can be replaced by an angular acceleration type rotation sensor for obtaining an angular velocity type signal through integration.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.