阅读说明：本技术 一种浅水条件下***子波测量装置和方法 (Air gun wavelet measuring device and method under shallow water condition ) 是由 米立军 张金淼 王建花 朱振宇 刘志鹏 王艳冬 于 2020-07-28 设计创作，主要内容包括：本发明涉及一种浅水条件下气枪子波测量装置和方法,包括依次连接的海底电缆,数据处理单元,垂直缆和浮体单元；海底电缆包括相互垂直的若干条海底电缆,各条海底电缆上均间隔相同距离设置若干第一种检波器组合,第一种检波器组合为包括磁电式检波器和压电检波器的双检检波器,用于检测平面内的气枪子波信号；垂直缆与海底电缆所在的平面垂直,且垂直缆上均匀设置若干水听器组合,用于检测垂直方向上的气枪子波信号；数据处理单元采集海底电缆和垂直缆采集的气枪子波信号,并对气枪子波信号进行分析处理；浮体单元用于使测量装置漂浮在水面上,从而确定测量装置位置。其更适用于浅水条件下远场子波采集,能够实现立体观测,测量精度显著提高。(The invention relates to a device and a method for measuring airgun wavelets under shallow water conditions, which comprises a submarine cable, a data processing unit, a vertical cable and a floating body unit which are connected in sequence; the submarine cable comprises a plurality of submarine cables which are vertical to each other, a plurality of first detector combinations are arranged on each submarine cable at the same interval, and each first detector combination comprises a magnetoelectric detector and a piezoelectric detector and is used for detecting air gun wavelet signals in a plane; the vertical cable is vertical to the plane of the submarine cable, and a plurality of hydrophone combinations are uniformly arranged on the vertical cable and used for detecting air gun wavelet signals in the vertical direction; the data processing unit acquires air gun wavelet signals acquired by the submarine cable and the vertical cable and analyzes and processes the air gun wavelet signals; the float unit is used for floating the measuring device on the water surface, thereby determining the position of the measuring device. The method is more suitable for far-field wavelet acquisition under the shallow water condition, can realize three-dimensional observation, and obviously improves the measurement precision.)

1. The air gun wavelet measuring device under the shallow water condition is characterized by comprising a submarine cable, a vertical cable, a data processing unit and a floating body unit which are sequentially connected;

the submarine cables comprise a plurality of submarine cables which are vertical to each other, a plurality of first detector combinations are arranged on each submarine cable at equal intervals, and each first detector combination comprises a magnetoelectric detector and a piezoelectric detector and is used for detecting air gun wavelet signals in a plane;

the vertical cable is vertical to the plane of the submarine cable, and a plurality of hydrophone combinations are uniformly arranged on the vertical cable and used for detecting air gun wavelet signals in the vertical direction;

the data processing unit acquires air gun wavelet signals acquired by the submarine cable and the vertical cable and analyzes and processes the air gun wavelet signals;

the floating body unit is arranged on the top of the vertical cable and used for floating the vertical cable on the water surface to determine the position of the vertical cable.

2. The air gun wavelet measuring device under shallow water conditions as claimed in claim 1, wherein said vertical cable comprises an operating section and a connecting section, said operating section comprises a vertical cable and a plurality of hydrophone assemblies disposed on said vertical cable and distributed at equal intervals, and said connecting section is sleeved outside each of said hydrophone assemblies.

3. The apparatus of claim 2, wherein the hydrophone assembly comprises at least two of the hydrophones, the hydrophones being piezoelectric geophones.

4. The air gun wavelet measuring device under shallow water conditions of claim 2 wherein said connecting segment is a high strength titanium alloy protective sleeve.

5. The airgun wavelet measuring device under shallow water conditions of claim 1 wherein an attitude sensor is provided in said float unit, said attitude sensor being connected to said data processing unit for controlling the inclination of the measuring device with respect to the vertical.

6. The air gun wavelet measuring device under shallow water conditions as claimed in claim 5, wherein said data processing unit comprises a seismic data acquisition module, a temperature sensor, a pressure sensor, a GPS positioning system and a power supply module, said seismic data acquisition module acquires data acquired by said temperature sensor, said pressure sensor and said GPS positioning system, said power supply module supplies power to said data processing unit.

7. The air gun wavelet measuring device under shallow water conditions as claimed in claim 6, wherein said seismic data acquisition module comprises a master control board, a first seismic data acquisition board, a second seismic data acquisition board, a third seismic data acquisition board, a temperature pressure acquisition board, an inclination data acquisition board and a GPS and power control board; the system comprises a first seismic data acquisition board, a second seismic data acquisition board, a third seismic data acquisition board, a temperature pressure acquisition board, a GPS and a power supply control board, wherein the first seismic data acquisition board, the second seismic data acquisition board and the third seismic data acquisition board are respectively used for acquiring wavelet signals of a vertical cable, a first submarine cable and a second submarine cable, the temperature pressure acquisition board is connected with the temperature sensor and the pressure sensor to realize acquisition and control of temperature and pressure, the inclination angle data acquisition board is connected with an attitude sensor to realize acquisition and control of an inclination angle of the device, the GPS is connected with the power supply control board, a GPS positioning system and the power supply module are used for positioning and supplying power to the device, and the master control board is connected with each acquisition board and the.

8. The air gun wavelet measuring device under shallow water conditions as claimed in claim 6, wherein a metal base is provided at the bottom of said data processing unit; the side walls of the data processing unit are respectively provided with a watertight connector of the data processing unit, which is used for watertight connection with the vertical cable and the submarine cable.

9. The shallow water air gun wavelet measuring device according to any one of claims 1-8, wherein a polyurethane solid material is filled between said submarine cable and said first geophone combination, and a polyurethane solid material is filled between said vertical cable and said hydrophone combination; the submarine cable and the vertical cable are both wrapped by polyamide materials, and Kevlar fibers are mixed in the polyamide materials.

10. A method for measuring airgun wavelet under shallow water condition, which comprises the following steps:

s1, testing the submarine cable and the vertical cable, and assembling the measuring device;

s2, after reaching a to-be-detected place, firstly putting the vertical cable and the floating body unit into water, then sinking the data processing unit into the sea, dragging one submarine cable to a specified position by using a boat, pulling the rope to slowly place the submarine cable to the sea, and then putting the other submarine cable to the specified position in the same way;

s3, determining and recording the position offset of the measuring device according to the changes of the tidal flow direction and the water depth in the area to be measured;

and after the S4 device is placed, the device activates a gas gun seismic source, digital-to-analog conversion is carried out on the acquired and received analog signals through the data processing unit, and the converted digital signals are fed back to the upper computer for storage and recording.

Technical Field

The invention relates to a device and a method for measuring air gun wavelets under shallow water conditions, and belongs to the technical field of seismic exploration.

Background

The far-field wavelet of the air gun seismic source is an important index for measuring the performance of the seismic source and is also important input data in seismic data processing. The far-field wavelet of the air gun source can relatively simply obtain the signal characteristics of the seismic air gun source, is easy to visualize and understand and is an important standard for measuring the performance of the source. Under shallow water conditions, the precision of the measured air gun wavelet is seriously influenced by complex multiple waves, guided waves, tides, surge and other special interference waves and water body structures, but the precision of the obtained data is lower because the measurement device which is commonly used at present under the shallow water conditions is a high-resolution multi-channel horizontal cable, and the resolution ratio of the measurement device is only capable of meeting the requirements of seismic exploration of middle-deep or shallow engineering and cannot meet the requirements of high-precision seismic exploration due to the fact that the measurement device is close to the sea level. The other method is a method for extracting from a shallow earthquake or a shallow stratum section, and the method has the defects of weak energy, poor anti-interference capability and the like, and cannot obtain accurate far-field wavelets of an air gun seismic source. In summary, it is difficult to obtain airgun wavelets through actual measurements in shallow water conditions.

Disclosure of Invention

In view of the above problems, an object of the present invention is to provide a device and a method for measuring airgun wavelets in shallow water, which are more suitable for far-field wavelet acquisition in shallow water, and can realize stereo observation with significantly improved measurement accuracy.

In order to achieve the purpose, the invention adopts the following technical scheme: a measuring device for airgun wavelets under shallow water conditions comprises a submarine cable, a vertical cable, a data processing unit and a floating body unit which are sequentially connected; the submarine cable comprises a plurality of submarine cables which are vertical to each other, a plurality of first detector combinations are arranged in each submarine cable at the same interval, and each first detector combination is a combination of a magnetoelectric detector and a piezoelectric detector and is used for detecting air gun wavelet signals in a plane; the vertical cable is vertical to the plane of the submarine cable, and a plurality of hydrophone combinations are uniformly arranged on the vertical cable and used for detecting air gun wavelet signals in the vertical direction; the data processing unit acquires air gun wavelet signals acquired by the submarine cable and the vertical cable and analyzes and processes the air gun wavelet signals; the float unit is used for floating the measuring device on the water surface, thereby determining the position of the measuring device.

Further, the vertical cable comprises a working section and a connecting section, the working section comprises the vertical cable and a plurality of hydrophone combinations which are distributed on the vertical cable at equal intervals, and the connecting section is sleeved outside each hydrophone combination.

Further, the second type of detector assembly is a hydrophone assembly, comprising at least two spaced apart piezoelectric detectors.

Further, the connecting section is a high-strength titanium alloy protective sleeve.

Further, an attitude sensor is arranged in the floating body unit, and the attitude sensor is connected with the data processing unit and used for controlling the inclination angle of the measuring device relative to the vertical direction

Furthermore, the data processing unit comprises a seismic data acquisition module, a temperature sensor, a pressure sensor, a GPS positioning system and a power module, the seismic data acquisition module acquires data acquired by the temperature sensor, the pressure sensor and the GPS positioning system, and the power module supplies power to the data processing unit.

Further, the seismic data acquisition module comprises a master control board, a first seismic data acquisition board, a second seismic data acquisition board, a third seismic data acquisition board, a temperature and pressure acquisition board, an inclination data acquisition board, a GPS and power control board; the system comprises a first seismic data acquisition board, a second seismic data acquisition board, a third seismic data acquisition board, a temperature pressure acquisition board, a power supply control board, a GPS (global positioning system) and a power supply module, wherein the first seismic data acquisition board, the second seismic data acquisition board and the third seismic data acquisition board are respectively used for acquiring wavelet signals of a vertical cable, a first submarine cable and a second submarine cable, the temperature pressure acquisition board is connected with the temperature sensor and the pressure sensor to realize acquisition and control of temperature and pressure, the inclination angle data acquisition board is connected with an attitude sensor to realize acquisition and control of an inclination angle of the device, the GPS is connected with the power supply control board, the GPS positioning system and the power supply module are used for positioning and supplying power to the device.

Further, a metal base is arranged at the bottom of the data processing unit; the side walls of the data processing unit are respectively provided with a watertight connector of the data processing unit for connecting with the watertight connectors of the vertical cable and the submarine cable.

Further, polyurethane solid materials are filled between the submarine cables and the first type of detector combination, and polyurethane solid materials are filled between the vertical cables and the second type of detector combination; the submarine cable and the vertical cable are both wrapped by polyamide materials, and Kevlar fibers are mixed in the polyamide materials.

The invention also discloses a method for measuring the air gun wavelet under the shallow water condition, which adopts any one of the air gun wavelet measuring devices under the shallow water condition and comprises the following steps: s1, testing the submarine cable and the vertical cable, and assembling the measuring device; s2, after reaching a to-be-detected place, firstly putting the vertical cable and the floating body unit into water, then sinking the data processing unit into the sea, dragging one submarine cable to a specified position by using a boat, pulling the rope to slowly place the submarine cable to the sea, and then putting the other submarine cable to the specified position in the same way; s3, determining and recording the position offset of the measuring device according to the changes of the tidal flow direction and the water depth in the area to be measured; and after the S4 device is placed, the device activates a gas gun seismic source, digital-to-analog conversion is carried out on the acquired and received analog signals through the data processing unit, and the converted digital signals are fed back to the upper computer for storage and recording.

Due to the adoption of the technical scheme, the invention has the following advantages: 1. a stereo observation mode is adopted, so that the measurement precision of the air gun wavelet under the shallow water condition is improved; 2. the change rule of the air gun wavelet can be monitored in the transverse direction and the longitudinal direction by adopting a combined measuring mode of a submarine cable and a vertical cable, so that richer and more complete air gun wavelet data can be obtained; 3. noise interference is relatively less, and the vertical cable and the submarine cable are far away from the sea surface, so that the influence of wave and surge noise is reduced; 4. the attitude sensor is arranged, so that the influence of the attitude of the measuring device on the wavelet can be corrected, and the measuring error is reduced; 5. the temperature and pressure sensors are arranged, so that temperature and pressure information during wavelet measurement can be acquired; 6. when analog signals are converted into digital signals, the time sampling rate is high and can reach 1/32ms, and the selectable sampling rate is more: 1/32ms, 1/16ms, 1/8m, 1/4ms, and 1/2 ms; the pre-amplification gain can be selectively controlled, and 12dB, 24dB, 36dB and 48dB can be selected.

Drawings

FIG. 1 is a schematic structural diagram of an air gun wavelet measuring device under shallow water conditions according to the present invention;

FIG. 2 is a schematic diagram of the structure of a hydrophone module in a vertical cable according to the invention;

FIG. 3 is a schematic diagram of the structure of a data processing unit of the present invention;

FIG. 4 is a top view of the data processing unit of the present invention;

fig. 5 is a schematic structural view of the floating body unit of the present invention.

Reference numerals:

1-a submarine cable; 11-a first detector combination; 12-a first submarine cable; 13-a second submarine cable; 2-vertical cables; 21-a hydrophone combination; 22-a connecting segment; 23-a hydrophone; 3-a data processing unit; 31-a seismic data acquisition module; 311-total control board; 312-a first seismic data acquisition panel; 313-a second seismic data acquisition board; 314-a third seismic data acquisition panel; 315-temperature pressure acquisition plate; 316-GPS and power control board; 32-a temperature sensor; 33-a pressure sensor; 34-a GPS positioning system; 35-a power supply module; 36-a metal base; 4-a floating body unit; 41-attitude sensor; 5-watertight joint.

Detailed Description

The present invention is described in detail by way of specific embodiments in order to better understand the technical direction of the present invention for those skilled in the art. It should be understood, however, that the detailed description is provided for a better understanding of the invention only and that they should not be taken as limiting the invention. In describing the present invention, it is to be understood that the terminology used is for the purpose of description only and is not intended to be indicative or implied of relative importance.