JP2005114446A - Efficient electric exploration method by radio-controlled electric field measuring system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problems, wherein in executing three-dimensional electric exploration in particular, large amount of labor is needed for wire connection to electrodes, when examination area extends over a wide range or when inter-electrode connection is difficult due to landform or vegetation and that measurement quality is lowered by noise getting mixed in data, when transmitting a signal via a cable, these being caused by conventional methods in which electrodes installed within the limits of examination have all been wire-connected for potential or electric field measurement. <P>SOLUTION: In this system, a small-sized measuring instrument is placed for each of measurement point groups, only adjoining electrodes are wire-connected with each other to measure a difference in the potential, thereby finding the magnitude of an electric field, and all the small-sized measuring instruments are radio controlled at a measurement headquarters, to solve defects caused by wire connection. In this system, two-dimensional electric field distribution on a ground surface, corresponding to current-carrying spots, is obtained by measuring the magnitude of electric fields of two orthogonal components at each observation spot to analyze underground three-dimensional electric characteristics. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electric exploration method for measuring underground electrical characteristics.

  In the conventional electrical exploration method, all the electrodes installed in the survey area are connected by wire, and various potential combinations are used to measure the potential or electric field at other electrodes when energized from one electrode. When the survey area is wide, or when it is difficult to connect the electrodes due to topography, vegetation, etc., it takes a lot of labor to connect the electrodes, and in addition, it is mixed in the measurement data when transmitting the signal through the cable. Measurement data quality was degraded due to noise.

  In particular, in the three-dimensional electrical exploration method, a large number of electrodes must be installed on the surface of the survey area, so wired connection has been a major obstacle.

  The problems of the prior art to be solved by the present invention are that, particularly when performing three-dimensional electrical exploration, the point that labor is required for the connection between the electrodes, and the quality deteriorates due to the noise mixed in during signal transmission. It is.

  When measuring potential, it is necessary to connect to a fixed reference point. However, since the magnitude of the electric field is obtained from the potential difference between adjacent electrodes, a small measuring instrument is installed at each measurement point. The problem is solved by connecting only the electrodes, measuring the potential difference, obtaining the magnitude of the electric field, and controlling all small measuring instruments wirelessly at the measurement headquarters.

  In the case of three-dimensional exploration, on the ground surface that includes the exploration target range, a two-dimensional electric field distribution is obtained by measuring the magnitude of the electric field in two orthogonal directions according to the current application point, By analyzing the underground three-dimensional electrical property distribution, the data obtained by the above measurement method can be used effectively.

1. Large-scale electric exploration represented by three-dimensional electric exploration method will be possible at practical cost and time.

2. Electrical exploration is possible even when the connection is difficult due to topography.

3. Three-dimensional electrical exploration is possible at a practical cost and time, and it is difficult to remove the influence of seawater in two-dimensional exploration, such as mountainous areas, complicated geographical features, complex and heterogeneous regions, and coastal areas. It becomes possible to apply the electric exploration method to various areas.

  The measurement system consists of a small measuring instrument with a function to measure the potential difference between adjacent electrodes arranged at each measurement point and a wireless data transmission function, and a wireless control / recorder installed at the measurement headquarters. The Thereby, the electric field distribution on the ground surface according to the current conduction point can be measured.

  Analyzing the electrical characteristics of the underground from the measured electric field distribution data, the analysis method using the pole dipole method electrode arrangement is used for two-dimensional exploration, and the two-dimensional exploration analysis method is extended for three-dimensional exploration. Use the method.

FIG. 3 shows an embodiment of the present invention, which shows a measuring device used for measurement. The measuring instrument arranged at each observation point includes a potential measuring function, a wireless receiving function, a trigger function by power reception, Modulation function of measurement potential, wireless transmission function of modulation signal, wireless control / recorder installed at measurement headquarters has function as wireless base station, modulation signal restoration function, digitization function, and recording function .

The flow of measurement work is
1. 1. After starting energization, call from the wireless base station to each potential measuring instrument to secure the communication line. 2. The electric field measurement signal at each point is modulated using the call signal as a trigger and wirelessly transmitted to the base station; 3. Restoring and recording the signal modulated at the base station. Repeat by moving the energization point sequentially.

  Fig. 4 shows the analysis method for three-dimensional exploration, and extends the analysis method of pole dipole method arrangement in two-dimensional exploration as orthogonal electric field distribution data obtained on the ground surface for each of various current conduction points. Analyzes the three-dimensional electrical property distribution in the underground.

It is the structure of the conventional electric survey measuring apparatus. It is the structure of the electrical survey measuring apparatus by the implementation method of this invention. Fig. 4 illustrates a measurement flow and functions built into the apparatus according to an embodiment of the present invention. Fig. 3 shows a flow of analysis according to an embodiment of the present invention.

Claims (2)

  In the electric exploration method that measures the distribution of electrical characteristics of the underground from the potential distribution or electric field distribution on the ground surface when current flows from any point on the ground surface, a measuring instrument with potential measurement function and wireless transmission function A measurement method that solves the problems caused by wired connections by measuring the electric field distribution on the surface of the earth by controlling it wirelessly from a measurement headquarters installed at a different location. The electric exploration method according to claim 1, particularly in the three-dimensional electric exploration method for analyzing the three-dimensional distribution of underground electrical characteristics, measuring the magnitude of electric fields in two orthogonal directions on the ground surface including the exploration target range. 3D electric exploration method to analyze underground 3D electrical property distribution by inverse analysis of 2D electric field distribution obtained by the above.

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