Device for measuring distribution depth and water pressure of multi-layer confined aquifer

Abstract

The utility model belongs to the field of multi-layer confined aquifer exploration in water-power engineering, and particularly relates to a device for measuring the distribution depth and water pressure of a multi-layer confined aquifer. According to the utility model, the design thought of drilling through one layer, isolating one layer and measuring one layer is adopted, and the positions of the top interface and the bottom interface of the confined aquifer are determined by using data measured by the aquifer interface detection sensor and the drainage condition of the outer end of the axial through hole of the drill rod; the measured drilling depth S1 and the measured drilling depth S2 correspond to the depth of the top interface of the confined water layer and the depth of the bottom interface of the confined water layer respectively. When the water pressure P1 and the water pressure P2 of the confined water layer are measured, the drill hole is sealed through the first annular air bag and the second annular air bag in advance, a sealed measurement environment can be provided for the water pressure measurement sensor, and the accuracy of a measurement result is fully ensured. The multi-layer confined aquifer distribution depth and water pressure measurement while drilling can be achieved at the same time, the measurement result is accurate, and the multi-layer confined aquifer distribution depth and water pressure measurement while drilling device has important significance on hydropower station construction.

Description

Technical Field

[0001] This utility model belongs to the field of surveying multi-layer confined aquifers in hydropower engineering, and more specifically relates to a device for measuring the distribution depth and water pressure of multi-layer confined aquifers. Background Technology

[0002] Some complex strata contain multiple confined aquifers, and the distribution of these confined aquifers has a significant impact on the selection of dam sites, reservoir leakage, and dam seepage prevention in hydropower projects.

[0003] The depth and pressure of multiple confined aquifers pose significant challenges to groundwater measurement. Existing technologies for measuring confined aquifer levels primarily include stop-drilling stratified logging, multi-stage monitoring wells, and geophysical methods. Stop-drilling stratified logging isolates the target aquifer by installing a packer system. When drilling through multiple aquifers, casing is installed and cemented. The confined head is measured by injecting / pumping water into the target layer. This method is inefficient, costly, and cannot provide real-time measurements while drilling. Multi-stage monitoring wells install multiple independent screens in parallel within the same borehole, each corresponding to an aquifer. Measurements are taken using wellhead gauges or downhole sensors, allowing for long-term continuous monitoring of multiple aquifer levels. However, this method requires prior knowledge of the confined aquifer distribution and involves complex well construction. Geophysical methods are limited in accuracy due to the influence of mineral composition and depth.

[0004] Existing patent literature on confined water level measurement mainly focuses on measuring the water pressure of confined water, and there is no method for simultaneously measuring the depth of the confined water layer. The relevant patent literature found is as follows:

[0005] Chinese patent document CN117738653A (publication date: March 22, 2024) discloses a device and method for measuring water pressure while drilling. The device includes an inlet / outlet allowing fluid to enter and exit, a flow test chamber connected to the inlet / outlet, a sealing measurement unit for sealing the inlet / outlet and measuring borehole inflow pressure, a packer for sealing the borehole, a hydraulic control unit for controlling the packer to close or open the borehole, a piston, and a pusher ring. This invention can measure borehole inflow pressure and fluid flow in real time at different locations by controlling the closing or opening of the borehole, eliminating the need for unnecessary actions such as lifting the drill string and changing drill collars. The main feature of the above solution is the improvement of the measurement while drilling and the water pressure measurement device. Its measurement object is the water pressure at the inflow point and location, and it cannot measure the distribution depth and water pressure of multiple confined aquifers.

[0006] Chinese patent document CN106192971A (published on December 7, 2016) discloses a structure for a confined aquifer level observation well and a method for multi-layer water level observation. The well structure consists of an observation hole and a well pipe placed outside the observation hole. Core sampling is performed through the observation hole into the confined aquifer, and the well pipe is placed within a water-stopping layer above the confined aquifer, allowing observation of the water level within the confined aquifer. To observe the water level of a lower confined aquifer, drilling continues within the observation hole to the lower confined aquifer, and two layers of confined aquifer level observation well pipes are inserted between the observation hole and the well pipe. This allows observation of the water level elevation and pressure head of two or more confined aquifers from a single well. However, this solution primarily improves upon the multi-layer water level observation well structure, requiring knowledge of the distribution depth of multiple confined aquifers before observing the confined water pressure. It cannot directly and simultaneously measure the distribution depth and pressure of multiple confined aquifers. Utility Model Content

[0007] The technical problem to be solved by this utility model is to provide a device for measuring the distribution depth and water pressure of multi-layer confined aquifers, which can simultaneously achieve relatively accurate measurement of the distribution depth and water pressure of multi-layer confined aquifers.

[0008] To solve the above-mentioned technical problems, this utility model adopts the following technical solution: a device for measuring the distribution depth and water pressure of multi-layered confined aquifers, including a drill bit, a drill rod, an air pump, and a ground monitoring system. The drill bit and the drill rod are coaxially and fixedly connected together. An aquifer interface detection sensor is fixedly installed on the outer circumferential surface of the drill rod at a position close to the drill bit. The aquifer interface detection sensor includes at least a lateral resistivity sensor and a spontaneous potential sensor. A first annular airbag, a water pressure measuring sensor, and a second annular airbag are fixedly arranged on the outer circumferential surface of the drill rod on the side of the aquifer interface detection sensor away from the drill bit. The first annular airbag, the water pressure measuring sensor, and the second annular airbag are arranged along the axial direction of the drill rod. The three components are arranged in a specific configuration, with the first annular airbag being closest to the aquifer interface detection sensor. The first annular airbag, the second annular airbag, and the drill rod are arranged coaxially. The first and second annular airbags are connected to the air pump via inflation and deflation pipelines. The first annular airbag has a first state where it can seal the borehole when inflated and a second state where it cannot seal the borehole when deflated. The second annular airbag also has a first state where it can seal the borehole when inflated and a second state where it cannot seal the borehole when deflated. The aquifer interface detection sensor and the water pressure measurement sensor are electrically connected to the ground monitoring system via wires. The drill rod has an axial through hole, which is connected to the outer surface of the drill bit via a connecting hole.

[0009] The preferred embodiment is that the drill pipe is composed of multiple drill pipe units that are coaxially fixedly connected, and a closed connection structure is formed between the side walls of two adjacent drill pipe units. The air filling and emptying pipelines are connected by pipe joints in the area corresponding to the connection of two adjacent drill pipe units, and the wires are connected by line joints in the area corresponding to the connection of two adjacent drill pipe units.

[0010] A preferred embodiment is that the sidewall of the axial through hole of the drill pipe is fixedly provided with a gas pipe laying pipe for laying gas filling and defilling pipelines and a wire laying pipe for laying wires.

[0011] A preferred embodiment is that multiple water pressure measuring sensors are arranged in a circular array around the axis of the drill rod, and multiple water pressure measuring sensors located on the same vertical distribution line on the outer circumference of the drill rod are located on the same independently set measuring line.

[0012] A preferred embodiment is that the aquifer interface detection sensor also includes a temperature sensor.

[0013] A preferred embodiment is that multiple lateral resistivity sensors are arranged in a circular array around the axis of the drill rod, and multiple lateral resistivity sensors located on the same vertical distribution line on the outer surface of the drill rod are located on the same independently set measurement line; multiple natural potential sensors are arranged in a circular array around the axis of the drill rod, and multiple natural potential sensors located on the same vertical distribution line on the outer surface of the drill rod are located on the same independently set measurement line; multiple temperature sensors are arranged in a circular array around the axis of the drill rod, and multiple temperature sensors located on the same vertical distribution line on the outer surface of the drill rod are located on the same independently set measurement line.

[0014] The specific implementation of this utility model includes the following steps:

[0015] Step 1: The first and second annular airbags are both in the second state beforehand, and the drill rod and drill bit are drilled vertically as a whole; the measurement data of the aquifer interface detection sensor are observed in real time using the ground monitoring system;

[0016] Step 2: When the aquifer interface detection sensor shows a decrease in resistivity and a negative SP curve, stop drilling, switch the second annular airbag to the first state, and wait for 10 to 15 minutes. If groundwater continuously flows out from the outer end of the axial through hole of the drill rod, and the color of the groundwater gradually becomes lighter until it is close to clear water, it is determined that the drill bit has entered the confined aquifer. At this time, record the drilling depth S1 of the drill bit and proceed to step 3; otherwise, repeat steps 1 and 2. It is preferable to use a scheme in which the aquifer interface detection sensor also includes a temperature sensor. In this case, the prerequisite for stopping drilling in step 2 is that when the aquifer interface detection sensor shows a decrease in resistivity and a negative SP curve, and the temperature measured by the temperature sensor decreases.

[0017] Step 3: The second annular airbag returns to the second state, and the drill bit continues to drill to the set depth until the water pressure measurement sensor enters the confined aquifer. At this time, both the first and second annular airbags are switched to the first state, and the water pressure P1 of the confined aquifer is measured by the water pressure measurement sensor.

[0018] Step four: The first and second annular airbags are both restored to the second state, and the drill bit continues to drill. The measurement data of the aquifer interface detection sensor is observed in real time using the ground monitoring system.

[0019] Step 5: When the aquifer interface detection sensor shows an increase in resistivity and a positive anomaly in the SP curve, stop drilling, switch the first annular airbag to the first state, and wait for 10 to 15 minutes. If the groundwater stabilizes and no longer flows out from the outer end of the axial through hole of the drill rod, it is determined that the drill bit has left the confined aquifer. At this time, record the drilling depth S2 of the drill bit and proceed to step 6; otherwise, repeat steps 4 and 5. When the aquifer interface detection sensor also includes a temperature sensor, the prerequisite for stopping drilling in step 5 is that the aquifer interface detection sensor shows an increase in resistivity and a positive anomaly in the SP curve, and the temperature measured by the temperature sensor increases.

[0020] Step 6: Switch the second annular airbag to the first state as well, and use the water pressure measurement sensor to measure the water pressure P2 of the confined water layer;

[0021] Step 7: Repeat steps 1 through 6 until the drill bit reaches the designed hole depth.

[0022] The beneficial effects of this invention are as follows: Adopting an overall design concept of "drilling through one layer, isolating one layer, and measuring one layer," when the drill bit penetrates the top interface of the confined aquifer, the data measured by the aquifer interface detection sensor will show characteristics such as decreased resistivity, a negative SP curve anomaly, and a decrease in temperature. Simultaneously, after the second annular airbag seals the borehole, groundwater will continuously flow out from the outer end of the axial through-hole of the drill rod. The drilling depth S1 measured at this time is the depth of the top interface of the confined aquifer. When the drill bit penetrates the bottom interface of the confined aquifer, the data measured by the aquifer interface detection sensor will show characteristics such as increased resistivity, a positive SP curve anomaly, and an increase in temperature. Simultaneously, after the first annular airbag seals the borehole, the groundwater will stabilize and will not flow out from the outer end of the axial through-hole of the drill rod. The drilling depth S2 measured at this time is the depth of the bottom interface of the confined aquifer. When measuring the water pressure P1 and P2 of the confined aquifer, pre-sealing the borehole through the first and second annular airbags provides a closed measurement environment for the water pressure measurement sensor, fully ensuring the accuracy of the measurement results. This invention can simultaneously measure the depth and water pressure of multiple confined aquifers while drilling, and the measurement results are relatively accurate, which is of great significance for the construction of hydropower stations. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0025] Figure 2 yes Figure 1 A schematic diagram of the AA cross-sectional structure;

[0026] Figure 3 yes Figure 1 A schematic diagram of the BB cross-sectional structure.

[0027] The components in the diagram are labeled as follows: Drill bit 1, aquifer interface detection sensor 2, lateral resistivity sensor 21, natural potential sensor 22, temperature sensor 23, first annular airbag 3, water pressure measurement sensor 4, second annular airbag 5, drill rod 6, drill rod axial through hole 61, ground monitoring system 7, air pump 8, air inflation / deflation pipeline 9, wire 10, air pipe laying pipe 11, wire laying pipe 12. Detailed Implementation

[0028] The technical solutions in the embodiments of this utility model will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0029] Please see Figures 1 to 3 This utility model discloses a device for measuring the distribution depth and water pressure of multiple confined aquifers, including a drill bit 1, a drill rod 6, an air pump 8, and a ground monitoring system 7. The drill bit 1 and the drill rod 6 are coaxially fixed together. An aquifer interface detection sensor 2 is fixedly installed on the outer circumferential surface of the drill rod 6, adjacent to the drill bit 1. The aquifer interface detection sensor 2 includes at least a lateral resistivity sensor 21 and a natural potential sensor 22. In a preferred embodiment, the aquifer interface detection sensor 2 also includes a temperature sensor 23. A first annular airbag 3, a water pressure measuring sensor 4, and a second annular airbag 5 are fixedly arranged on the outer circumferential surface of the drill rod 6 on the side of the aquifer interface detection sensor 2 away from the drill bit 1. The three are arranged sequentially along the axial direction of the drill rod 6, with the first annular airbag 3 being closest to the aquifer interface detection sensor 2. The first annular airbag 3, the second annular airbag 5, and the drill rod 6 are arranged coaxially. The first annular airbag 3 and the second annular airbag 5 are connected to the air pump 8 through the inflation and deflation pipelines 9, respectively. The first annular airbag 3 has a first state in which it can seal the borehole when inflated and a second state in which it does not seal the borehole when deflated. The second annular airbag 5 also has a first state in which it can seal the borehole when inflated and a second state in which it does not seal the borehole when deflated. The aquifer interface detection sensor 2 and the water pressure measurement sensor 4 are electrically connected to the ground monitoring system 7 through the wires 10, respectively. The drill rod 6 has an axial through hole 61, which is connected to the outer surface of the drill bit 1 through a connecting hole.

[0030] To improve the accuracy of measurement data, multiple aquifer interface detection sensors 2 and water pressure measurement sensors 4 can be arranged. Specifically, multiple water pressure measurement sensors 4 are arranged in a circular array around the axis of the drill rod 6, and multiple water pressure measurement sensors 4 located on the same vertical distribution line on the outer surface of the drill rod 6 are located on the same independently set measurement line; multiple lateral resistivity sensors 21 are arranged in a circular array around the axis of the drill rod 6, and multiple lateral resistivity sensors 21 located on the same vertical distribution line on the outer surface of the drill rod 6 are located on the same independently set measurement line; multiple natural potential sensors 22 are arranged in a circular array around the axis of the drill rod 6, and multiple natural potential sensors 22 located on the same vertical distribution line on the outer surface of the drill rod 6 are located on the same independently set measurement line; multiple temperature sensors 23 are arranged in a circular array around the axis of the drill rod 6, and multiple temperature sensors 23 located on the same vertical distribution line on the outer surface of the drill rod 6 are located on the same independently set measurement line. This is equivalent to arranging multiple sensor measurement strips evenly spaced along the circumference of the drill pipe 6. Each sensor measurement strip has multiple corresponding sensors spaced along the axial direction of the drill pipe 6. Taking the aquifer interface detection sensor 2 as an example, in the preferred embodiment shown in the attached figure, there are 2 symmetrically arranged lateral resistivity sensor measurement strips, 2 symmetrically arranged spontaneous potential sensor measurement strips, and 2 symmetrically arranged temperature sensor measurement strips spaced along the annular direction, totaling 6 sensor measurement strips. The adjacent sensor measurement strips are evenly spaced (i.e., the corresponding central angle distance is 60°). The lateral resistivity sensor 21 is the Rt sensor, and the spontaneous potential sensor 22 is the SP sensor. In specific implementation, the lateral resistivity sensor 21 and spontaneous potential sensor 22 are mainly used for measurement, while the temperature sensor 23 is mainly used for auxiliary verification. The lateral resistivity sensor 21 can achieve detection within a radial range of 1m to 2m through the "focused electrode array + four-electrode method + mud correction" method; the spontaneous potential sensor 22 can suppress drilling fluid interference through intrusion correction, salinity calibration, etc., thereby effectively ensuring the accuracy of the measurement results. The water pressure measurement sensor 4 is mainly used to measure the water pressure of stable pressurized water. Various high-precision water pressure measurement sensors that meet design requirements can be selected. With the above structural design, on the one hand, it avoids the entire circuit from malfunctioning due to a single measurement circuit failure; on the other hand, under normal circumstances, multiple measurement circuits can measure simultaneously, and the accuracy of the measurement can be improved by combining all the data for evaluation.

[0031] The first annular airbag 3 and the second annular airbag 5 can generally be made of pressure-resistant rubber bladders. After inflation, they can seal the corresponding borehole section and isolate the aquifer interface. This invention is mainly used for low-pressure (0.1 MPa~1.0 MPa) and medium-pressure (1.0 MPa~10.0 MPa) confined aquifers. When the pressure of the confined aquifer is too high, the weight of the drilling rig is difficult to balance the water pressure. The second annular airbag 5 is mainly used to isolate the hydrostatic pressure of the drilling fluid and to prevent measurement interference from the water pressure of other confined aquifers above; the first annular airbag 3 is mainly used to close the reverse circulation channel to avoid measurement errors caused by the continuous discharge of the measured confined aquifer to the surface.

[0032] To facilitate drilling, drill rod 6 is generally composed of multiple drill rod units fixedly connected coaxially. A closed connection structure is formed between the sidewalls of adjacent drill rod units. Correspondingly, the air filling / defilling pipeline 9 is connected via a pipe joint in the area corresponding to the connection between adjacent drill rod units, and the wire 10 is connected via a line connector in the area corresponding to the connection between adjacent drill rod units. It is understood that the specific connection structure involved in the airtight connection between the sidewalls of adjacent drill rod units can be implemented using common knowledge known to those skilled in the art; for example, two drill rod units can be connected and fixed using a fixing ring and bolt connection assembly, and a sealing ring can be installed at the joint to ensure a tight seal. The inflation and deflation of the airbag can be achieved using the inflation / deflation pipeline 9, which can be implemented using common knowledge known to those skilled in the art. For example, the inflation / deflation pipeline 9 can share the same air pipe, and an inflation / deflation connector can be installed at the ground surface. The inflation / deflation connector can be in the form of an air nozzle (refer to the inflation / deflation method of items such as footballs and basketballs). In some alternative embodiments, the inflation / deflation connector can also be in the form of a three-way valve, with one port for connecting to the corresponding airbag, one port for connecting to the air pump 8, and the other port for connecting to an openable / closable exhaust port. Of course, in some alternative embodiments, the inflation / deflation pipeline 9 can also be provided with separate inlet and exhaust pipes, and openable / closable shut-off valves can be installed on the inlet and exhaust pipes respectively. The inlet pipe is used to connect to the air pump 8.

[0033] The air filling / defilling pipe 9 and the wire 10 can generally be laid and connected through the axial through hole 61 of the drill pipe. The air filling / defilling pipe 9 can generally adopt a flexible hose structure. In order to better protect the air filling / defilling pipe 9 and the wire 10, an air pipe laying pipe 11 for laying the air filling / defilling pipe 9 and a wire laying pipe 12 for laying the wire 10 can also be fixedly installed on the side wall of the axial through hole 61 of the drill pipe.

[0034] The specific implementation of this utility model includes the following steps:

[0035] Step 1: The first annular airbag 3 and the second annular airbag 5 are both in the second state beforehand, and the drill rod 6 and the drill bit 1 are drilled vertically as a whole; the ground monitoring system 7 is used to observe the measurement data of the aquifer interface detection sensor 2 in real time.

[0036] Step 2: When the measurement data of the aquifer interface detection sensor 2 shows a decrease in resistivity and a negative anomaly in the SP curve, stop drilling, switch the second annular airbag 5 to the first state, and wait for 10 to 15 minutes. If groundwater continuously flows out from the outer end of the axial through hole 61 of the drill rod, and the color of the groundwater gradually becomes lighter until it is close to clear water, it is determined that the drill bit 1 has entered the confined aquifer. At this time, record the drilling depth S1 of the drill bit 1 and proceed to step 3; otherwise, repeat steps 1 and 2. It is preferable to use a scheme in which the aquifer interface detection sensor 2 also includes a temperature sensor 23. In this case, the prerequisite for stopping drilling in step 2 is that when the measurement data of the aquifer interface detection sensor 2 shows a decrease in resistivity and a negative anomaly in the SP curve, and the temperature measured by the temperature sensor 23 decreases.

[0037] Step 3: The second annular airbag 5 returns to the second state, and the drill bit 1 continues to drill to the set depth (the specific drilling depth can be determined according to the axial distance between the drill bit 1 and the water pressure measuring sensor 4 in the device) until the water pressure measuring sensor 4 enters the confined water layer. At this time, the first annular airbag 3 and the second annular airbag 5 are both switched to the first state, and the water pressure P1 of the confined water layer is measured by the water pressure measuring sensor 4.

[0038] Step four: The first annular airbag 3 and the second annular airbag 5 are both restored to the second state, and the drill bit 1 continues to drill. The ground monitoring system 7 is used to observe the measurement data of the aquifer interface detection sensor 2 in real time.

[0039] Step 5: When the measurement data of the aquifer interface detection sensor 2 shows an increase in resistivity and a positive anomaly in the SP curve, stop drilling, switch the first annular airbag 3 to the first state, and wait for 10 to 15 minutes. If the groundwater stabilizes and no longer flows out from the outer end of the axial through hole 61 of the drill rod, it is determined that the drill bit 1 has left the confined aquifer. At this time, record the drilling depth S2 of the drill bit 1 and proceed to step 6; otherwise, repeat steps 4 and 5. When the aquifer interface detection sensor 2 preferably includes a temperature sensor 23, the prerequisite for stopping drilling in step 5 is that when the measurement data of the aquifer interface detection sensor 2 shows a decrease in resistivity and a negative anomaly in the SP curve, and the temperature measured by the temperature sensor 23 decreases.

[0040] Step 6: Switch the second annular airbag 5 to the first state and use the water pressure sensor 4 to measure the water pressure P2 of the pressurized water layer.

[0041] Step 7: Repeat steps 1 through 6 until drill bit 1 has drilled to the designed hole depth.

[0042] "Negative SP curve anomaly" refers to a negative deviation of the SP (Self-Potential) curve relative to the baseline in spontaneous potential logging; "positive SP curve anomaly" refers to a positive deviation of the SP (Self-Potential) curve relative to the baseline in spontaneous potential logging. It is understood that the deviation magnitudes corresponding to "negative SP curve anomaly" and "positive SP curve anomaly" can be reasonably determined by those skilled in the art based on actual operating conditions. Similarly, the resistivity control thresholds corresponding to "resistivity decrease" and "resistivity increase" mentioned above can be reasonably determined by those skilled in the art based on actual operating conditions, as can the temperature control thresholds corresponding to "temperature decrease" and "temperature increase."

[0043] The overall design concept of this utility model is "drill through one layer, isolate one layer, and measure one layer." When the drill bit 1 drills into the top interface of the confined aquifer, the data measured by the aquifer interface detection sensor 2 will show characteristics such as decreased resistivity, negative SP curve anomaly, and decreased temperature. Simultaneously, after the second annular airbag 5 seals the borehole, groundwater will continuously flow out from the outer end of the axial through-hole 61 of the drill rod. The drilling depth S1 measured at this time is the depth of the top interface of the confined aquifer. When the drill bit 1 drills into the bottom interface of the confined aquifer, the data measured by the aquifer interface detection sensor 2 will show characteristics such as increased resistivity, positive SP curve anomaly, and increased temperature. Simultaneously, after the first annular airbag 3 seals the borehole, the groundwater will stabilize and will not flow out from the outer end of the axial through-hole 61 of the drill rod. The drilling depth S2 measured at this time is the depth of the bottom interface of the confined aquifer. When measuring the water pressure P1 and P2 of the confined aquifer, pre-sealing the borehole through the first annular airbag 3 and the second annular airbag 5 provides a closed measurement environment for the water pressure measuring sensor 4, fully ensuring the accuracy of the measurement results.

[0044] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0045] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A device for measuring the distribution depth and water pressure of multiple confined aquifers, comprising a drill bit (1), a drill rod (6), and a ground monitoring system (7), wherein the drill bit (1) and the drill rod (6) are coaxially and fixedly connected together, characterized in that, The system includes an air pump (8), and a water-bearing interface detection sensor (2) is fixedly installed on the outer periphery of the drill rod (6) at a position close to the drill bit (1). The water-bearing interface detection sensor (2) includes at least a lateral resistivity sensor (21) and a natural potential sensor (22). On the outer periphery of the drill rod (6), a first annular airbag (3), a water pressure measurement sensor (4), and a second annular airbag (5) are fixedly arranged on the side of the water-bearing interface detection sensor (2) away from the drill bit (1). The first annular airbag (3), the water pressure measurement sensor (4), and the second annular airbag (5) are arranged sequentially along the axial direction of the drill rod (6), and the first annular airbag (3) is closest to the water-bearing interface detection sensor (2). (3) The second annular airbag (5) and the drill rod (6) are arranged coaxially; the first annular airbag (3) and the second annular airbag (5) are connected to the air pump (8) through the inflation and deflation pipeline (9), the first annular airbag (3) has a first state that can seal the borehole when inflated and a second state that does not seal the borehole when deflated, the second annular airbag (5) has a first state that can seal the borehole when inflated and a second state that does not seal the borehole when deflated; the aquifer interface detection sensor (2) and the water pressure measurement sensor (4) are electrically connected to the ground monitoring system (7) through the wire (10); the drill rod (6) has an axial through hole (61), and the axial through hole (61) is connected to the outer surface of the drill bit (1) through the connecting hole.

2. The device for measuring the distribution depth and water pressure of multiple confined aquifers according to claim 1, characterized in that, The drill rod (6) is composed of multiple drill rod units that are coaxially fixedly connected. A closed connection structure is formed between the side walls of two adjacent drill rod units. The air filling and emptying pipeline (9) is connected to the corresponding area of ​​the connection part of two adjacent drill rod units through a pipe joint. The wire (10) is connected to the corresponding area of ​​the connection part of two adjacent drill rod units through a line joint.

3. The device for measuring the distribution depth and water pressure of multiple confined aquifers according to claim 1, characterized in that, The side wall of the axial through hole (61) of the drill rod is fixedly provided with a gas pipe laying pipe (11) for laying the gas filling and discharging pipeline (9) and a wire laying pipe (12) for laying the wire (10).

4. The device for measuring the distribution depth and water pressure of multiple confined aquifers according to claim 1, characterized in that, The water pressure measuring sensor (4) is provided with multiple water pressure measuring sensors (4) arranged in a ring array around the axis of the drill rod (6). Multiple water pressure measuring sensors (4) located on the same vertical distribution line on the outer circumference surface of the drill rod (6) are located on the same independently set measuring line.

5. The apparatus for measuring the distribution depth and water pressure of multiple confined aquifers according to any one of claims 1 to 4, characterized in that, The aquifer interface detection sensor (2) also includes a temperature sensor (23).

6. The apparatus for measuring the distribution depth and water pressure of multiple confined aquifers according to claim 5, characterized in that, The lateral resistivity sensor (21) is arranged in a ring array around the axis of the drill rod (6). The multiple lateral resistivity sensors (21) located on the same vertical distribution line on the outer peripheral surface of the drill rod (6) are located on the same independently set measurement line. The natural potential sensor (22) is arranged in a ring array around the axis of the drill rod (6). The multiple natural potential sensors (22) located on the same vertical distribution line on the outer peripheral surface of the drill rod (6) are located on the same independently set measurement line. The temperature sensor (23) is arranged in a ring array around the axis of the drill rod (6). The multiple temperature sensors (23) located on the same vertical distribution line on the outer peripheral surface of the drill rod (6) are located on the same independently set measurement line.

Images