JP3047453U - Physical inspection equipment in boreholes - Google Patents

Abstract

(57) [Summary] [Problem] A temperature sensor and a flow meter attached to the tip of a signal cable are held in the body of a physical inspection device and lowered into a borehole, so that groundwater (hot spring) can be measured with a flow meter.
The subject is to easily measure the subtle temperature change of the groundwater (hot spring) with the temperature sensor at the spring point of the spring. Kind Code: A1 A physical inspection device in a borehole for inspecting the temperature of groundwater flowing out from a crack in a rock in the borehole and the location of the groundwater discharge. Physical inspection device body 1
The temperature sensor 2 and the flow meter 3 are held, and the temperature sensor 2 and the flow meter 3 are connected to a signal cable 4 for extracting the temperature information signal and the flow information signal obtained from the temperature sensor 2 and the flow meter 3 to the ground. A physical inspection device in a boring hole, characterized by being connected and configured.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a physical inspection device in a borehole for inspecting a subtle temperature change of groundwater (hot spring) flowing from a crack in a rock in the borehole and a location of the groundwater discharge.

[0002]

[Prior art]

Conventionally, there are generally the following logging methods for physical logging in a borehole (physical inspection in a hole). (1) Resistivity logging As shown in FIG. 3, a boring hole H is drilled in the formation E, and an electrode A disposed at a predetermined lower position of the boring hole H and an electrode B disposed on the ground surface. between, a current flows from the power supply S, the electrodes _{M 1} at a position on 25cm from the electrode a, the electrode _{M 2} to 50cm upper position Ri by electrode a, further, the position of 100cm layer above electrode a the electrode _{M 3} is disposed, the electrodes _{M 1,} M 2, _{M 3} and the cable _C 1 between the electrode N which is disposed to the _surface, C 2, a voltmeter _{V 1} which is connected via a _{C 3} , V ₂ , and V ₃ , and measure the specific resistance in the borehole.

(2) Measurement of self-potential As shown in FIG. 4, a boring hole H is drilled in a formation E, and an electrode M provided at a predetermined lower layer position of the boring hole H and a boring hole H are provided on the ground surface. The potential difference is measured with a potentiometer P connected to the electrode N via a cable C. (3) Temperature logging This involves drilling a borehole in the formation and lowering a temperature sensor such as a thermistor connected to the cable into the borehole to measure the temperature in the borehole.

[0004]

[Problems to be Solved by the Invention] In the above-mentioned resistivity logging and self potential measurement, changes in lithology and stratum boundaries are well reflected, but there is no ability to search for small cracks due to the arrangement of electrodes and other factors. Therefore, there was a problem that it was difficult to explore groundwater (hot springs) that gushed out from fine rock fractures. Further, the above-mentioned temperature logging has a problem that it is difficult to detect spring water from a small temperature crack or a small crack. Therefore, this invention is based on the idea that the physical inspection equipment, which holds the temperature sensor and the flow meter (flow meter) connected to the end of the signal cable, is lowered into the boring hole and the temperature changes in the boring hole and the groundwater (hot spring) The purpose of the present invention is to provide a physical inspection device in a borehole capable of inspecting a well spot.

[0005]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention provides a physical inspection device in a borehole for inspecting a temperature of groundwater flowing out from a crack in rock in the borehole and a location of a groundwater discharge, and a hole diameter of the borehole. A physical inspection device made of a rod having a smaller outer diameter holds a temperature sensor 2 and a flow meter 3 in a main body 1 of the apparatus. The temperature information signal and the flow information signal obtained from the temperature sensor 2 and the flow meter 3 are grounded. A signal cable 4 for connection to the temperature sensor 2 and the flowmeter 3 is connected to a physical inspection device in a borehole. With such a physical inspection device in the boring hole, the temperature sensor 2 and the flow meter 3 attached to the tip of the signal cable 4 are lowered into the boring hole by being held by the physical inspection device body 1. The flowmeter 3 can measure the location of the spring of the groundwater (hot spring), and the temperature sensor 2 can measure the subtle temperature change of the groundwater (hot spring).

[0006]

[Embodiment of the invention]

 Hereinafter, an embodiment of the physical inspection device in the borehole according to the present invention will be described in detail with reference to the drawings. As shown in FIG. 1, the physical inspection device in the borehole of the present invention has a temperature sensor 2 in the middle of a physical inspection device body 1 made of a rod having an outer diameter smaller than the diameter of the borehole drilled in the formation. A signal for holding a flow meter (flow meter) 3 at the lower end of the physical inspection device main body 1 and extracting a temperature information signal and a flow information signal obtained from the temperature sensor 2 and the flow meter 3 to the ground. A cable (multi-core cable) 4 is connected to the temperature sensor 2 and the flow meter 3, and a hanging wire 6 is locked to the physical inspection device main body 1.

The physical inspection apparatus body 1 is made of a stainless steel round bar, but is not limited to this. Further, the holding positions of the temperature sensor 2 and the flow meter 3 on the physical inspection device main body 1 are not limited to the above-described embodiment. For example, the flow meter 3 is held at an intermediate portion of the physical inspection device main body 1. Alternatively, the temperature sensor 2 may be held at the lower end of the physical inspection device main body 1. The temperature sensor 2 converts the temperature into an electric signal and transmits the electric signal to the ground via a signal cable 4. The flow meter 3 is adjusted to move at a flow rate of 0.02 m / s to 10 m / s. The movement is converted into an electric signal by electromagnetic induction and transmitted to the ground via a signal cable. In order to hold the physical inspection device main body 1 at the center of the hole diameter in the boring hole, the center holding members 5, 5 having an outer diameter slightly smaller than the hole diameter of the boring hole are attached to the physical inspection device main body 1. It is provided on the outer periphery of the upper and lower parts.

The specific dimensions (size) of the physical inspection device in the boring hole according to the present invention are as follows: the overall length is 1500 mm, the outer diameter of the physical inspection device main body 1 is 35 mm, and the center holding member 5 Although the outer diameter is 70 mm, it is not limited to this size.

Since the physical inspection device in the borehole according to the present invention is configured as described above, the temperature sensor 2 and the flowmeter 3 held by the physical inspection device main body 1 and connected to the signal cable 4 are provided. As the water is lowered into the boring hole, the flow meter 3 can measure the location of the spring of the groundwater (hot spring), and the temperature sensor 2 can measure the subtle temperature change of the groundwater (hot spring). Figure 2 shows the determination example of spring water with temperature gradients and flow rate ratio according to go down the physical inspection device of the boring hole of this invention in the borehole (hot spring), the depth of L _{1 m} from the ground surface In, there is no change in the temperature gradient and the flow velocity ratio, and it can be seen that there is no groundwater flow in the hole. In addition, it can be seen that at the depth of L ₂ m from the surface of the earth, there is a change of (+) in the temperature gradient, there is no change in the velocity ratio, but only the change of lithology. In addition, at a depth of L ₃ m from the surface of the ground, it can be seen that there is a change in the temperature gradient (−), a change in the flow velocity ratio (+), and the inflow of low-temperature water. In addition, at the depth of L ₄ m from the surface of the ground, the temperature gradient and the flow velocity ratio change by (+), indicating that there is inflow of hot water.

[0010]

[Effect of the invention]

 As described above, the present invention is a physical inspection device in a borehole for inspecting the temperature of groundwater flowing out from a crack in rock in the borehole and the location of the groundwater discharge. A physical inspection device main body made of a rod having an outer diameter smaller than the diameter of the boring hole holds a temperature sensor and a flow meter, and transmits a temperature information signal and a flow information signal obtained from the temperature sensor and the flow meter to the ground. The temperature sensor and the flow meter are connected to a signal cable for taking out the battery. This was used as a physical inspection device in the borehole. The body of the physical inspection device is equipped with a temperature sensor and a flow meter attached to the end of the signal cable, which are lowered into the borehole. Temperature changes can be easily measured.

[Brief description of the drawings]

FIG. 1 is a side view of a physical inspection device in a borehole of the present invention.

FIG. 2 shows an example of determination of spring water (hot spring) based on the temperature gradient and the flow velocity ratio in the borehole by the physical inspection device in the borehole according to the present invention.

FIG. 3 is a diagram showing a method of resistivity logging according to a conventional example.

FIG. 4 is a diagram showing a method for measuring a self potential according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Physical inspection apparatus main body 2 Temperature sensor 3 Flow meter (flow meter) 4 Signal cable (multi-core cable) 5 Center holding member 6 Hanging wire

Claims (1)

[Utility model registration claims] 1. A physical inspection device in a borehole for inspecting a temperature of groundwater flowing out from a crack in a rock in the borehole and a location of the groundwater, wherein the rod has an outer diameter smaller than the diameter of the borehole. A temperature sensor (2) and a flow meter (3) are held in the manufactured physical inspection device body (1), and a temperature information signal and a flow information signal obtained from the temperature sensor (2) and the flow meter (3). Characterized in that a signal cable (4) for taking out the ground to the ground is connected to the temperature sensor (2) and the flow meter (3).