JP3513758B2 - Visualization method of arbitrary section of ground - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for conducting various physical surveys by visualizing the ground by an image based on physical properties such as electric resistivity and elastic wave velocity, and particularly, forming a boring hole forming a survey line on the ground. The present invention relates to a method suitable for physical exploration, that is, velocity exploration, electrical logging, density logging, acoustic logging, resistivity tomography, elastic wave tomography, electromagnetic tomography and the like.

[0002]

2. Description of the Related Art Conventionally, various physical surveys have been carried out for exploring underground ground conditions, that is, stratum structures, artificial modification directly under existing structures, residual foreign substances, cavities, pollution, and the like.
With regard to such geophysical exploration, the exploration accuracy has been remarkably improved in combination with the rapid progress of sensor technology and computer technology, and it is also possible to visualize it by computer image so that the ground condition can be seen at a glance. .

[0003]

However, the improvement of the exploration accuracy and the visualization by the computer image are the advances accompanying the improvement of the sensor technology and the computer technology used for carrying out various physical explorations. The method of implementation itself has not improved, and it still follows the conventional method of implementation. This can be easily understood by considering, for example, the case where the existing geological condition directly under the obstacle such as the existing structure, the water system such as rivers and lakes, the road, the railway line is measured by the conventional physical survey.

That is, when there is an obstacle for measurement such as an existing structure, physical survey such as electric survey in which a survey line is provided on the ground surface approaches the obstacle because the obstacle interferes with the survey line. It is virtually impossible to explore the ground condition. On the other hand, in the case of geophysical exploration such as resistivity tomography and elastic wave tomography, since multiple boring holes that form the survey line are formed vertically while avoiding obstacles, it is likely that the geophysical exploration approached from the ground surface. It is relatively easy to visualize the ground condition in a vertical section (vertical section) without being restricted by various obstacles. However, even with these geophysical surveys, it is impossible to form a boring hole directly below the obstacle on the measurement, and when visualizing the ground condition in a horizontal cross section (horizontal cross section), It is necessary to form a pair of large vertical shafts that can secure the work space and the installation space for the excavating machine, etc., and also to excavate horizontal holes for arranging various sensors and vibration sources between the vertical shafts. In terms of human labor, a considerable burden is required.

Further, in addition to the cost burden and the like, the present physical exploration follows the conventional method of implementation, and thus limits the exploration accuracy. The reason is as follows. Generally, in natural ground, various layers are deposited with a predetermined regularity according to the rules of the natural world. Each of the deposited layers has, for example, a characteristic of a high specific resistance showing a high specific resistance to electric conduction, or a characteristic of a low specific resistance showing a low specific resistance, and the properties thereof are various. It possesses a tendency. Here, for example, as shown in FIG. 8, there is a ground consisting of three layers G1, G2 and G3 which are horizontally deposited.
Assume 3 is a high resistivity and layer G2 is a low resistivity. When the ground is measured along the line A-A ', it is difficult for electricity to flow through the layers G1 and G3, which are high-resistivity bodies, and the internal structures of the layers G1 and G3 and the layer G are generated due to generation of false images.
There is a problem that the existence of 2 cannot be accurately measured. Also, when measured along the line B-B ', electricity bypasses the layers G1 and G3, which are high-resistivity bodies, and concentrates in the layer G2, which is a low-resistivity body, which is more likely to flow. There is a problem that the internal structure of the layers G1 and G3 cannot be accurately measured due to generation or the like. Therefore, in order to eliminate the anisotropy of natural ground, which makes accurate analysis difficult as much as possible, and perform highly accurate measurement,
It is preferable to lay both A ′ and the survey line BB ′ and perform the measurement. However, the line A-
If A'and survey line BB 'are laid, a considerable burden is required in terms of cost and human labor.
If there is a measurement obstacle such as an existing structure on the ground surface directly above, it is virtually impossible to provide the survey line A itself by the conventional method, and there is a limit to the improvement of the survey accuracy. .

As for the anisotropy of natural ground, since the layers forming the ground are deposited with a predetermined regularity in accordance with the rules of the natural world as described above, if the history of natural phenomena occurring in the ground is traced, It is possible to infer an approximate outline of the layer structure, and in that sense, it is possible to make some post-hoc corrections by compensating the measurement results obtained by geophysical surveys. However, even if the problem of anisotropy of natural ground can be solved to some extent based on speculation, the layer G
1, such as when there is a cavity S in G3 (see Fig. 8) or when the natural ground is artificially modified, there are irregular elements in the ground that cannot be inferred from the natural rules alone. If it exists, as shown in FIG.
It is extremely difficult to perform an accurate survey unless both A ′ and survey line BB ′ are laid and measured. However, as described above, it is impossible to further improve the survey accuracy by the conventional method. difficult.

The present invention has been made against the background of the above-mentioned conventional techniques, and its purpose is to visualize the ground with an arbitrary cross section and with high accuracy regardless of the presence or absence of an obstacle for measurement such as an existing structure. It is to provide a method of performing geophysical exploration so as to be able to do so.

[0008]

In order to achieve this object, the present invention provides a drilling head having a nozzle hole for jetting a drilling liquid obliquely forward and a transmitting means for sending the position information of the drilling head. Of the plurality of rods connected along the direction, the rod is connected to the foremost end in the excavation direction, and while monitoring the position information from the transmitting means, the excavation head is rotated and the excavation liquid is discharged from the nozzle hole. By blasting the ground and digging the ground in any direction, a survey line hole is formed that goes in any direction at any depth, and the ground is visualized in the survey hole by physical properties such as electrical resistivity and elastic wave velocity. Provided is a method for visualizing an arbitrary cross section of a ground by laying a sensor, a vibration source, and the like necessary for carrying out a predetermined physical exploration and performing the physical exploration.

In the method for visualizing an arbitrary cross section of the ground according to the present invention, while the position information from the transmitting means provided in the excavation head is monitored, the excavation head is rotated and the excavation fluid is ejected from the nozzle hole in an arbitrary excavation direction. Excavate the ground to form a survey hole of any depth, direction and length.
Then, in the formed survey line, the sensors and vibration sources necessary for carrying out a predetermined physical survey to visualize the ground by physical properties such as electric resistivity and elastic wave velocity are laid, and the physical survey is performed. Carry out. Therefore, according to the method of the present invention, it is possible to form a survey hole in the underground in any manner regardless of the presence or absence of an obstacle for measurement such as an existing structure. Can be visualized with an arbitrary cross section and with high accuracy.

The method of visualizing an arbitrary cross section according to the present invention as described above is based on geotomography such as resistivity tomography, elastic wave tomography, electromagnetic wave tomography in which various sensors and vibration sources must be arranged so as to surround the cross section to be searched. It is particularly suitable for conducting exploration. These geophysical surveys are based on the existence of obstacles in measurement as described above for visualization of the ground condition immediately below obstacles such as existing structures and visualization of the ground condition in cross section (horizontal direction). It is impossible to provide a survey line due to the restriction of the physical cost and the cost and human labor. However, according to the above-mentioned present invention, an arbitrary survey line can be formed underground, which is conventionally impossible. It was possible to carry out exploration to visualize the ground condition with an arbitrary cross section, which greatly expands the scope of geophysical geophysical exploration, and significantly improves exploration accuracy. Is obtained. That is, in the arbitrary cross-section visualization method of the present invention, at least two pairs of the above-mentioned survey line holes are formed immediately below an existing structure, river or other measurement obstacle on the surface of the earth, and various geotomographic images are formed. Can be configured to perform a geophysical exploration.

The "cross section" visualized by the arbitrary cross section visualization method of the present invention does not mean only a two-dimensional cross section. That is, as described above, since the survey line can be formed in any manner in the arbitrary section visualization method of the present invention, for example, two upper survey lines that are parallel to each other and a deeper mutual survey line can be formed. By laying two parallel upper survey lines and performing various types of geotomography, it is possible to perform a three-dimensional, three-dimensional, three-dimensional visualization of the ground, not just a two-dimensional cross section. The “cross section” in the present invention is used as a term including a case where such three-dimensional visualization is made in three dimensions.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a method for visualizing an arbitrary section of the ground according to the present invention will be described below with reference to the drawings.

There have been various methods of physical exploration for visualizing the cross section of the ground condition under the ground. In this embodiment, an example in which the cross sectional visualization by resistivity tomography is applied will be described as an example. Of course, it can be applied not only to resistivity tomography but also to other geophysical surveys by forming survey line holes including elastic wave tomography, and electrical exploration to explore the ground condition by approaching from the surface without forming survey line holes. For geophysical exploration, etc., it is possible to form a survey hole in the shallow layer in the horizontal direction and apply it by simulating it as a ground surface.

FIG. 1 shows a schematic view of the implementation of the method for visualizing an arbitrary cross section according to this embodiment. In this embodiment, the ground condition immediately below the existing building 1 is visualized with an inclined cross section. On the ground surface on both sides of the existing building 1, the starting point h
i is formed by excavating measurement line holes 2 and 3 that open to the surface of the arrival port ho, and electrode cables 5 and 6 in which a plurality of electrodes 4 are connected at a predetermined interval are connected to each of the measurement line holes 2 and 3. Has been done. As shown in FIG. 1A, the electrode cable 5 is laid directly under the existing building 1, and the electrode cable 6 is laid below the electrode cable 6 with a predetermined depth interval d1. In addition, as shown in FIG. 1B, the electrode cable 5
Is laid so that the inclined portion 5a and the horizontal portion 5b connecting the electrode 4 are aligned with each other. On the other hand, in the electrode cable 6, the inclined portion 6 a is laid with a distance d2 from the electrode cable 5 by a predetermined distance.
The horizontal portion 6b following a is laid so as to be parallel to the electrode cable 5. After laying the electrode cables 5 and 6 in this manner, the exploration device 7 to which these electrode cables 5 and 6 are connected is operated on the ground to acquire, analyze, and image data necessary for resistivity tomography. By performing an exploration consisting of a series of operations, the ground condition can be visualized on the inclined section 8 immediately below the existing building 1 (see FIG. 2).

Next, a method of laying the electrode cables 5 and 6 as shown in FIG. 1 in order to visualize the inclined section 8 as described above will be described. The excavation performed in this embodiment is
The excavator 9 as shown in FIG. 3 is used. This excavating device 9 has a cylindrical main body 10 containing various devices.
And an excavation head 11 for excavating the ground.

The main body 10 is provided with a drive motor 12 for rotationally driving the excavation head 11. The drive motor 12 is connected to the rear end 11a of the excavation head 11 via a rotary shaft 12a and a connecting arm 13. Has been done. Reference numeral 14 denotes an excavation control unit, which includes an azimuth detection sensor 15 for detecting an excavation direction, an inclination angle detection sensor 16 for detecting an inclination angle with respect to the horizontal when the excavation device 9 is excavating, a transmitter 17, and an excavation operation. And a controller 18 that operates.

The excavation head 11 has an inclined surface on one side, and this inclined surface slides on the hole walls of the line-measuring holes 2 and 3 which are not weakened by the drilling mud W, whereby the excavation head 11 as a whole. Is guided to the ground portion weakened by the excavation mud W. Further, at the tip of the excavation head 11, there is a nozzle hole 1 for ejecting the drilling mud W obliquely forward.
1b is formed and one end of a flexible water supply pipe 19 is connected. At the rear end 11a of the excavation head 11,
An engagement flange 11c is formed and is engaged with the inward flange 10a of the main body 10.

In the excavation device 9 having the above-mentioned structure, the rear end 10b of the main body 10 is a cylindrical rod 2 formed of a rigid body such as metal.
It is linked to 0. A plurality of other rods are connected in series to the rear end of the rod 20, and the rod at the rearmost end is connected to a hydraulic unit (not shown) installed on the ground. Then, the propulsive force of the excavation head 11 is given through the frontmost rod 20 by the hydraulic unit pressing a series of rods. Further, the water supply pipe 19 extending from the excavator 9 and the excavation control unit 1
The signal line 14a extending from No. 4 and the power supply line 12b of the drive motor 12 are connected to the exploration device 7 provided on the ground through the inside of a series of rods. The exploration device 7 includes a tank or pump for supplying the drilling mud W to the water supply pipe 19, a hydraulic unit for laterally pressing the rod, measuring devices necessary for performing the resistivity tomography, and the excavation head 11. A control device and the like for monitoring the position and, if necessary, sending a control signal from the ground to the controller 18 are included.

In order to form the survey line hole 2 for the electrode cable 5 with the excavation device 9, the excavation device 9 is first excavated obliquely downward from the starting port hi. The starting port hi is sufficient as a space that is a trigger necessary for the tip of the excavation head 11 of the excavation device 9 to enter, and no large-scale excavation work is required. When the excavation is carried out obliquely downward, the drive motor 12 of the excavation device 9 receives a drive signal from the controller 18 to constantly rotate the excavation head 11 in the direction of the arrow R without stopping the excavation mud W from the nozzle hole 11b. Eject in all directions. As a result, the ground portion that stands in the direction of excavation is weakened, so that the excavation head 11 is pushed backward by the rod 20 and proceeds straight diagonally downward.

In this way, when the target depth distance is dug up to the distance of the length of the inclined portion 5a of the electrode cable 5, it is necessary to go horizontal in this time. The excavation head 11 is rotated in the arrow direction R so as to come to the upper position pu indicated by 4. As a result, the excavation mud W is ejected in a specific direction that is close to horizontal, so that the excavation head 11 gradually changes the excavation direction horizontally (obliquely upward with respect to the excavation direction).

In addition, according to the same principle as this, the excavation head 1
When 1 is to be moved diagonally to the right with respect to the excavation direction, it is to the right side position pr (see FIG. 4), and when it is to be moved diagonally to the left side, it is moved to the left side position pl, and when it is moved diagonally downward. The nozzle holes 11b may be located at the lower position pd by rotating the excavation head 11 respectively. Diagonally above right
In the case of downward or diagonally upward left / downward, the nozzle holes 11b may be similarly positioned in the desired direction. Also,
At the time of excavation, the excavation control unit 14
The excavation direction and the excavation angle detected by the azimuth detection sensor 15 and the inclination angle detection sensor 16 built in are sent by the controller 18 through the signal line 14a. Therefore, this is monitored and a different direction from the planned excavation direction. If it is moving to the position, the control signal is sent to the controller 18 so as to appropriately correct the traveling direction, and the controller 18 rotates the excavation head 11 to cause the nozzle hole 11 to move.
Finely adjust the position of b.

When the excavation in the horizontal direction is started, the excavation head 11 is constantly rotated this time so that the excavation mud W is ejected in all directions so as not to proceed in a specific direction. Then, when excavation is performed for a distance corresponding to the length of the horizontal portion 5b of the electrode cable 5 which is the target distance, the nozzle hole 1
1b is rotated to the upper position pu, and the excavation device 9 is advanced until reaching the arrival port 3 in the same manner as above.

In this way, the line measuring hole 2 for laying the electrode cable 5 is formed. Then, the work of pulling back the excavation device 9 to the starting port hi is performed in reverse, but at this time, the electrode cable 5 is attached to the excavation device 9 and the laying work is also performed at the same time. As described above, the laying work of the electrode cable 5 serving as the survey line is completed. Subsequently to this, in the same manner as described above, the measurement line hole 3 is formed and the work of laying the electrode cable 6 is performed. Then, finally, the exploration device 7 is operated to execute the underground exploration by resistivity tomography.

In the above embodiment, an example was shown in which the electrode cables 5 and 6 were laid vertically to visualize the ground condition in a vertical section (vertical section) (see FIG. 2). The excavation device 9 forms a survey hole so as to be laid at the same depth as the cable 6 (however, the horizontal distance d2 remains unchanged), and the ground condition is cross-sectional (horizontal cross-section).
It is of course possible to visualize with. An example thereof is shown in FIG. In the example of FIG. 5, in order to search the ground condition under the river 21, the river 21 starts from the riverbeds 22 and 23.
A pair of measuring line holes 2 so that they extend horizontally and parallel just below
4, 25 are formed in the same manner as in the above embodiment, and the electrode cables 26, 27 are laid there. Then, if the exploration device 7 to which the electrode cables 26 and 27 are connected is operated on the ground to conduct the exploration by the resistivity tomography, the ground condition can be visualized in the horizontal section 28 even just below the river 21.

In the above description, an example in which the ground is visualized in a two-dimensional cross section has been described. However, as shown in FIG. 6, for example, the ground can be visualized three-dimensionally in three dimensions.
FIG. 6 shows four measuring line holes 30, 31, 3 just below the road 29.
2 and 33 are formed to form electrode cables 34 and 3 respectively.
In this example, 5, 36 and 37 are laid. Then, if an exploration such as geotomography is performed in this way, it can be visualized three-dimensionally in three dimensions, and it can also be visualized in a number of two-dimensional cross sections. Even if the ground condition is highly likely to be modified, it will be possible to perform highly accurate exploration. Then, in order to carry out such highly accurate exploration, it is not necessary to stop traffic or to dig up the pavement, and the survey line holes 30, 31, 32, 33 from the side of the road 29.
Since it can be easily formed, it is possible to reduce not only the cost and labor, but also the obstacle caused by the work to the surrounding environment.

In the above embodiment, the measurement line holes 2, 3, 24,
After forming 25, the electrode cables 5, 6, 26, and 27 are arranged in the holes as they are. However, when the excavation device 9 is pulled back, the electrode cables 5, 6, 26, and 27 are attached to the excavation device 9.
Not only 6 but also a pipe material for protection such as protection may be laid at the same time.

Further, in the above embodiment, the excavation device 9
Of the azimuth data and the tilt angle data detected by the azimuth detection sensor 15 and the tilt angle detection sensor 16 of the controller 18
The signal is sent to the ground-based exploration device 7 through the signal line 14a, but not the signal line 14a but the transmitter 1
You may make it wirelessly transmit to the exploration apparatus 7 using 7.

Further, instead of the excavator 9 as shown in the above embodiment, an excavator 38 as shown in FIG. 7 can be used. The excavation device 38 includes an excavation head 39 and a main body 40, and the main body 40 has the rod 20 similar to that of the above-described embodiment. Body 40
Is only equipped with an electromagnetic wave transmitter 41 as a transmitting means having a coil inside, and has a simple internal configuration not equipped with the controller 18 and the like as in the above-described embodiment. Then, the position information of the excavation head 39 is acquired by receiving the electromagnetic wave transmitted from the ground on the ground. In this excavating device 38, the excavation head 39 does not rotate with respect to the main body 40. Therefore, in order to change the excavation direction of the excavator 38, the plurality of rods 20 and the excavation head 39 connected by the hydraulic unit provided on the ground are rotated. Even if the excavation device 38 has a simple structure, the arbitrary section visualization method according to each of the above-described embodiments can be implemented.

[0029]

According to the method of visualizing an arbitrary cross section of the ground of the present invention, it is possible to provide an innovative method of performing physical survey which cannot be achieved by the conventional physical survey. In particular, even under the existing structure, it becomes possible to visualize the ground condition at a desired cross section with various physical properties such as electrical resistivity and elastic wave velocity with high exploration accuracy. Can be expected to be utilized in.

[Brief description of drawings]

FIG. 1 is an explanatory diagram schematically showing an implementation outline of a method for visualizing an arbitrary section of the ground immediately below an existing building according to one embodiment, in which a sectional view (a) is a front sectional view and a sectional view (b) is a sectional view. (A)
FIG. 6 is a plan sectional view seen from the SA-SA line direction of FIG.

FIG. 2 is a side sectional view taken along the line SB shown in FIG.

FIG. 3 is an internal schematic diagram showing a schematic configuration of an excavation device used in the arbitrary section visualization method of FIG.

FIG. 4 is a side view taken along the line SC of FIG. 3 (a).

5A and 5B are diagrams schematically showing an implementation point of a method for visualizing an arbitrary section of the ground immediately below a river according to another embodiment, where FIG. 5A is a plan sectional view and FIG. 5B is an SD-SD line. Side sectional view.

FIG. 6 is a diagram schematically showing an implementation point of a method of visualizing an arbitrary section of the ground according to still another embodiment.

FIG. 7 is an explanatory diagram showing a schematic configuration of an excavation device according to another embodiment.

FIG. 8 is an explanatory diagram showing a ground condition.

[Explanation of symbols]

1 Existing building A few holes 7 exploration equipment 8 inclined section 9 Drilling equipment (drilling head) 11 Digging head 11b nozzle hole 17 Transmitter (Transmission means) 18 Controller (Transmission means) 20 rod 21 rivers 22,23 riverbed 24,25 survey line holes 28 horizontal section 29 road 30, 31, 32, 33 Survey line hole 38 Drilling equipment (drilling head) 39 digging head 40 body 41 Electromagnetic wave transmitter (transmitting means) W drilling fluid

─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Takehiko Imazato 658-2 Hongo-cho, Funabashi, Chiba Nihon Underground Exploration Co., Ltd. (72) Inventor Tsuyoshi Katsuta 27-22, Matsukaze-cho, Hiratsuka-shi, Kanagawa Lions Viale Shonan Matsukaze 208 (56) Reference JP 2000-310682 (JP, A) JP 54-35101 (JP, A) JP 2000-204883 (JP, A) JP 5-164855 (JP, A) JP JP 11-72323 (JP, A) JP 11-52062 (JP, A) JP 2001-64957 (JP, A) JP 2001-64956 (JP, A) JP 2001-116853 (JP, A) Japanese Patent Laid-Open No. 9-72192 (JP, A) Japanese Patent Publication No. 4-26397 (JP, B2) Patent 3404015 (JP, B2) Patent 3041426 (JP, B2) Munenori Hatanaka, Akihiko Uchida, Takehiko Imazato, Masahiro Matsumura, " Chemical liquid by resistance tomography Quantitative Evaluation of Improving Range ", Proceedings of Geotechnical Research Presentation, Japan, Society of Human Engineers Geotechnical Society, June 18, 1999, 34th-1999 (2 in 2 volumes)-, p. 1239-1240 Akihiko Uchida, Munenori Hatanaka, Masahiro Matsumura, Takehiko Imazato, "Quantitative evaluation of improvement range of chemical injection by resistivity tomography", Proceedings of underground space symposium, Japan, Japan Society of Civil Engineers, January 10, 1999, Volume 4, p. 269-274 Hiromasa Nakauchi, Mitsutoshi Hayashi, Ryoichi Hasegawa, Kazuyuki Ota, “Development of Intelligent Non-cutting Method”, Proc. Of the Japan Society for Geophysical Exploration Proceedings, Japan, October 2000, 103rd (Heisei 12 Autumn), p. 181-184 Hitoshi Yamauchi, Mitsuhiro Kasamikami, “Method for purification of soil and groundwater pollution using horizontal wells”, Journal of the Japan Sewage Society, Japan, Japan Society of Groundwater, November 30, 1998, Volume 40, No. 4. , P. 455-466 (58) Fields investigated (Int. Cl. ⁷ , DB name) G01V 1/00-3/40 E02D 1/00-1/08 E21B 47/00-49/10 E21D 9/00 -9/14 JISST file (JOIS)

Claims (3)

(57) [Claims] 1. An excavation head having a nozzle hole for ejecting the excavation liquid obliquely forward and a transmission means for transmitting the position information of the excavation liquid is connected to one another along the length direction, and the maximum number of rods in the excavation direction is selected. By connecting to the rod at the front end, while monitoring the position information from the transmitting means, by rotating the excavation head and ejecting the excavation fluid from the nozzle hole to excavate the ground in any direction of excavation , Existing structure
Things, the ground below the obstacle on measurements rivers, forming at least two survey lines holes toward any direction at any depth
Once formed a step, each survey line holes, soil electrical resistivity, implementing such sensors and excitation source necessary to predetermined geophysical survey to be visualized in physical properties such as acoustic wave velocity, drilling head and the rod
A laying worker who pulls it back and pulls it into the survey line hole to lay it
And the sensor and vibration source laid in each measurement hole
Any cross section visualization method of ground that perform the steps of performing said geophysical Te. 2. A sensor, a vibration source, etc. in the laying step
The method for visualizing an arbitrary cross section of the ground according to claim 1 , wherein a protective pipe for covering the ground is also laid . 3. An excavation head having a nozzle hole for ejecting the excavation liquid obliquely forward and a transmission means for transmitting the position information of the excavation liquid, the maximum number of rods in the excavation direction among a plurality of rods connected along the length direction. By connecting to the rod at the front end, while monitoring the position information from the transmitting means, by rotating the excavation head and ejecting the excavation fluid from the nozzle hole to excavate the ground in any direction of excavation, The process of forming at least two survey line holes in any direction at an arbitrary depth in the ground below existing obstacles such as structures and rivers, and if each survey hole is formed, the electrical resistivity of the ground , A laying process of laying a sensor and a vibration source, etc. necessary for performing a predetermined physical survey that visualizes the physical properties such as elastic wave velocity, and a protective tube that covers this inside the measurement line hole, and each measurement line hole The cell laid inside Any cross section visualization method of the ground to perform the step of performing the geophysical exploration using such service or excitation source.