A device suitable for long-term observation of basement water pressure and slip velocity in mountain glaciers

Abstract

This invention discloses a measuring device for measuring the base water pressure and slip velocity of mountain glaciers suitable for long-term observation. Belonging to the field of measurement, it includes an armored cable, an upper spherical cover, a lower sphere, a rubber sleeve, a partition, a water pressure sensor, a friction screw, an encoder, a reel mounting plate, a cable reel, and a slip ring. The upper spherical cover and lower sphere are fixedly connected to form a hollow sphere, inside which is housed the cable reel. When the armored cable slips with the glacier, it is released from the measuring device, thus solving the problem of cable breakage due to glacier movement and enabling long-term observation. Simultaneously, the encoder on the cable reel measures the release speed of the armored cable, thereby obtaining the glacier base slip velocity. The measuring device is filled with low-temperature resistant silicone oil, eliminating the need for a sealed pressure chamber for electrical components, resulting in a simple structure and low cost. The measuring device provided by this invention does not change its measuring position due to rapid glacier movement, enabling fixed-point observation of the water pressure beneath the ice.

Description

Technical Field

[0001] This invention belongs to the field of measurement and relates to a device for measuring the water pressure and slip velocity of glacier basement, and in particular to a device for measuring the water pressure and slip velocity of mountain glaciers that can be observed over a long period of time. Background Technology

[0002] The cryosphere is a vital freshwater resource for Earth, serving as the source of many of the world's major rivers. Its changes are inextricably linked to human life and social development. Most meltwater generated on the glacier surface flows to the glacier floor through crevasses and vertical shafts, and then to the glacier terminus via subglacial drainage systems. The residence time and discharge pathways of meltwater within glaciers significantly impact watershed runoff processes. Sudden discharges of water stored within glaciers can trigger flash floods, glacial lake outbursts, and debris flows, directly affecting public welfare. Research indicates a complex relationship between subglacial water pressure and the flow path of meltwater beneath glaciers. Drainage systems dominated by subglacial cavities may be associated with high water pressure, promoting rapid glacial sliding by reducing ice-rock interface coupling. Conversely, the evolution of channel-dominated drainage systems may be accompanied by relatively lower water pressure, leading to slower glacial sliding. Therefore, measuring the water pressure of subglacial water systems can indirectly reflect the subglacial hydrological characteristics of mountain glaciers. Currently, the commonly used method for observing subglacial water pressure involves drilling a full-depth borehole into the glacier and then inserting a water pressure sensor inside to observe changes in the water level. However, due to the extremely low temperature of the glacier, the liquid water inside the borehole will freeze and close due to the cooling effect of the glacier ice, making this method unsuitable for long-term observation. Furthermore, because the glacier is constantly moving, the water level sensor inside the borehole will move with the glacier, resulting in changes in the measurement location and making fixed-point observation of subglacial water pressure impossible. Long-term observation of subglacial water pressure remains a significant challenge. Summary of the Invention

[0003] The purpose of this invention is to solve the problem that the base water pressure and slip velocity of mountain glaciers cannot be observed for a long time, and to provide a long-term observation device for measuring the base water pressure and slip velocity of mountain glaciers.

[0004] The technical solution adopted by this invention to achieve the above objectives is: a device suitable for long-term observation of water pressure and slip velocity at the base of mountain glaciers, characterized in that it comprises: an armored cable, an upper spherical cover, a lower sphere, a rubber sleeve, a partition, a heating plate, a water pressure sensor, a friction screw, an encoder, a reel mounting plate, a cable reel, and a slip ring. The upper spherical cover and the lower sphere are fixedly connected together to form a hollow sphere, the interior of which is filled with low-temperature resistant silicone oil, the density of which is greater than that of water. The upper spherical cover has an axially penetrating central hole. The rubber sleeve is installed in the central hole of the upper spherical cover. One end of the armored cable passes through the rubber sleeve and is wound around the cable reel, and is electrically connected to the slip ring. The other end is connected to surface power supply and signal acquisition equipment. A space is left between the rubber sleeve and the armored cable for glacial water to enter. The slits in the sphere; the partition is coaxially disposed inside the sphere; the heating plate is bonded to the lower surface of the partition, and both the heating plate and the partition have through holes evenly distributed, the through holes on the heating plate and the through holes on the partition being identical in shape and number, and corresponding one-to-one; the reel mounting plate is fixed above the partition by screws, and the reel mounting plate has shaft holes; the two ends of the rotating shaft of the cable reel are rotatably mounted in the shaft holes of the reel mounting plate by bearings; a friction screw is installed on the top of the reel mounting plate, used to adjust the clamping force of the friction screw on the rotating shaft of the cable reel by rotating the friction screw, thereby adjusting the rotational torque of the cable reel; the encoder and slip ring are respectively installed at both ends of the rotating shaft of the cable reel; the water pressure sensor is installed below the heating plate; the encoder, heating plate and water pressure sensor are electrically connected to the slip ring.

[0005] Furthermore, the armored cable has a steel wire armor layer or a Kevlar fiber armor layer.

[0006] Furthermore, a limiting step is formed between the upper ball cover and the lower ball, and the upper ball cover and the lower ball are fixed together by countersunk screws.

[0007] Furthermore, an inner step is formed on the inner surface of the lower sphere for placing the partition and the heating plate, and the fixing ring is disposed on the inner wall of the lower sphere for pressing and fixing the partition and the heating plate.

[0008] Furthermore, the upper ball cover, lower ball, and retaining ring are connected by countersunk screws.

[0009] Furthermore, the water pressure sensor is mounted below the heating plate via a clamp, and the clamp, heating plate, and partition are fixed together with screws.

[0010] Through the above design scheme, the present invention can bring the following beneficial effects:

[0011] 1. The mountain glacier basement water pressure and slip velocity measuring device provided by the present invention, which is suitable for long-term observation, is placed directly in the bedrock or sediment under the ice. The rapid movement of the glacier will not change the measuring position of the measuring device, and can realize fixed-point observation of the water pressure under the ice.

[0012] 2. The measuring device for measuring the water pressure and slip velocity of the base of a mountain glacier, which is suitable for long-term observation, provided by the present invention is equipped with a cable reel. When the armored cable inside the ice slips with the glacier, the armored cable is released from the measuring device, thereby solving the problem of cable breakage caused by glacier movement and enabling long-term observation. At the same time, the encoder on the cable reel can measure the release speed of the armored cable, thereby obtaining the slip velocity of the glacier base.

[0013] 3. The measuring device for measuring the base water pressure and slip velocity of mountain glaciers, which is suitable for long-term observation, provided by this invention is filled with low-temperature silicone oil to protect the electrical components, eliminating the need for a sealed pressure chamber for the electrical components. This results in a simple structure and low cost. The heating plate arranged inside the measuring device can heat the measuring device to ensure that the surrounding environment of the measuring device is in a meltwater environment, effectively ensuring the accuracy of the water pressure measurement. Attached Figure Description

[0014] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and are used to understand the invention. They do not constitute an improper limitation of the invention. In the drawings:

[0015] Figure 1 This is an external schematic diagram of a device suitable for long-term observation of the basement water pressure and slip velocity of a mountain glacier.

[0016] Figure 2 A cross-sectional view from the first direction of a measuring device suitable for long-term observation of basement water pressure and slip velocity in mountain glaciers;

[0017] Figure 3 This is a cross-sectional view from the second direction of a measuring device suitable for long-term observation of basement water pressure and slip velocity in mountain glaciers.

[0018] Figure 4 Axonometric view of a measuring device suitable for long-term observation of basement water pressure and slip velocity in mountain glaciers;

[0019] Figure 5 A schematic diagram of a device for measuring the basement water pressure and slip velocity of mountain glaciers suitable for long-term observation.

[0020] The markings in the diagram are as follows: 1-Armored cable; 2-Upper ball cover; 3-Counterhead screw; 4-Lower ball; 5-Rubber sleeve; 6-Retaining ring; 7-Partition plate; 8-Heating plate; 9-Clamping plate; 10-Water pressure sensor; 11-Friction screw; 12-Encoder; 13-Roller mounting plate; 14-Cable reel; 15-Slip ring. Detailed Implementation

[0021] To more clearly illustrate the present invention, the following description, in conjunction with preferred embodiments and accompanying drawings, further clarifies the invention. Those skilled in the art should understand that the specific description below is illustrative rather than restrictive and should not be construed as limiting the scope of protection of the invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains.

[0022] To avoid obscuring the essence of this invention, well-known methods, processes, procedures, components, and circuits are not described in detail.

[0023] like Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, a device for measuring the base water pressure and slip velocity of a mountain glacier suitable for long-term observation includes an armored cable 1, an upper ball cover 2, a countersunk screw 3, a lower ball 4, a rubber sleeve 5, a fixing ring 6, a partition 7, a heating plate 8, a clamping plate 9, a water pressure sensor 10, a friction screw 11, an encoder 12, a reel mounting plate 13, a cable reel 14, and a slip ring 15.

[0024] The upper spherical cover 2, the lower spherical body 4, and the fixing ring 6 are connected by countersunk screws 3. A limiting step is formed between the upper spherical cover 2 and the lower spherical body 4 to achieve positioning and ensure that the overall shape of the measuring device is spherical. An inner step is formed on the inner surface for placing the partition 7 and the heating plate 8. The fixing ring 6 is set inside the lower spherical body 4, and a gap is left between it and the inner step of the lower spherical body 4 to fix the partition 7 and the heating plate 8.

[0025] The reel mounting plate 13 is fixed to the upper surface of the partition plate 7 by screws, and the reel mounting plate 13 has shaft holes. The two ends of the rotating shaft of the cable reel 14 are rotatably mounted in the shaft holes of the reel mounting plate 13 by bearings, so that the cable reel 14 can rotate freely. A friction screw 11 is installed on the top of the reel mounting plate 13. By rotating the friction screw 11, a certain clamping force can be applied to the cable reel 14 to prevent the armored cable 1 from being released from the cable reel 14 during the lowering of the measuring device. An encoder 12 and a slip ring 15 are respectively connected to the two ends of the rotating shaft of the cable reel 14. The partition plate 7 is coaxially arranged inside the sphere, and the partition plate 7 divides the interior of the measuring device into upper and lower spaces. The heating plate 8 is bonded to the lower part of the partition plate 7. The heating plate 8 and the partition plate 7 are placed on the step inside the lower sphere 4 and pressed and fixed by the fixing ring 6. The water pressure sensor 10 is installed below the heating plate 8 by a clamping plate 9, and the clamping plate 9, the heating plate 8 and the partition plate 7 are fixed together by screws. Through holes are evenly provided on the partition plate 7 and the heating plate 8. The through holes on the heating plate 8 are the same in shape and number as those on the partition plate 7. At the same time, the through holes on the heating plate 8 correspond one-to-one with those on the partition plate 7 and are arranged vertically opposite each other to allow power supply and signal lines to pass through. They also serve as a connecting channel between the upper and lower spaces inside the measuring device, so that the entire space inside the measuring device forms a connected cavity, which facilitates the transmission of liquid pressure to the water pressure sensor 10.

[0026] The upper ball cover 2 has an axially penetrating central hole. The rubber sleeve 5 is installed in the central hole of the upper ball cover 2. One end of the armored cable 1 passes through the rubber sleeve 5 and is wound around the cable reel 14, and is electrically connected to the slip ring 15. The other end is connected to the ground power supply and signal acquisition equipment. The encoder 12, the heating plate 8, and the water pressure sensor 10 are respectively electrically connected to the slip ring 15.

[0027] When the armored cable 1 is not extended, the measuring device is filled with low-temperature resistant silicone oil. The density of the low-temperature resistant silicone oil should be greater than that of water to prevent damage to the encoder 12, heating plate 8, and water pressure sensor 10 due to glacial meltwater intrusion. The low-temperature resistant silicone oil is a commercially available silicone oil with a temperature range of -40℃, such as phenyl silicone oil, and a density greater than that of water, such as phenyl silicone oil.

[0028] When the armored cable 1 is released from the measuring device, the internal volume of the measuring device increases and the silicone oil level drops. At this time, a small amount of external glacial water will enter the measuring device through the gap between the armored cable 1 and the rubber sleeve 5 and float on the silicone oil with a higher density, thereby further ensuring that the electrical components are protected from the influence of glacial water.

[0029] A gap is left between the rubber sleeve 5 and the armored cable 1, through which the pressure of the water system under the ice can be transmitted to the silicone oil inside the measuring device, and further transmitted to the water pressure sensor 10 inside the measuring device, and measured by the water pressure sensor 10.

[0030] Furthermore, the upper ball cover 2 and the lower ball 4 are made of transparent engineering plastics such as plexiglass to reduce the weight of the measuring device and provide good corrosion resistance. The spherical shape formed by the connection of the upper ball cover 2 and the lower ball 4 ensures that it has good pressure resistance.

[0031] Furthermore, the clamping force of the friction screw 11 on the rotating shaft of the cable reel 14 should be appropriate. On the one hand, it is necessary to prevent the armored cable 1 from being released from the cable reel 14 when the measuring device is lowered. On the other hand, after the measuring device is installed in place, when the armored cable 1 moves with the glacier, it is necessary to ensure that the armored cable 1 can be released from the cable reel 14 in an orderly manner.

[0032] Furthermore, the armored cable 1 should have a steel wire armor layer or a Kevlar fiber armor layer to ensure that the armored cable located at the interface between the glacier and the substrate will not break as it moves with the glacier.

[0033] The encoder 12, heating plate 8 and water pressure sensor 10 mentioned above are all existing devices, therefore, their specific models and specifications are not described in detail.

[0034] Figure 5 A schematic diagram of the working process of a mountain glacier basement water pressure and slip velocity measuring device suitable for long-term observation is shown. A and B show two working states of the device. According to the layout direction of the attached diagram, the operation should be performed in the direction indicated by the arrows in the diagram: A represents the state of the mountain glacier basement water pressure and slip velocity measuring device suitable for long-term observation, in which the measuring device is lowered into the bedrock or sediment borehole under the ice through a drill hole; B represents the state of the mountain glacier basement water pressure and slip velocity measuring device suitable for long-term observation, in which after the glacier slips, the armored cable 1 in the ice slips with the glacier, and the measuring device is still in the bedrock borehole to monitor the water pressure at the initial point.

[0035] Working principle of the invention:

[0036] Before deployment, the long-term observation-suitable mountain glacier basement water pressure and slip velocity measuring device provided by this invention should first be drilled in the glacier and subglacial bedrock or sediment. Then, the device should be lowered into the drilled hole in the subglacial bedrock or sediment. Power should be supplied to the measuring device. At this time, the subglacial liquid water will transmit pressure to the silicone oil inside the measuring device through the gap between the rubber sleeve 5 and the armored cable 1, and the pressure will be measured by the water pressure sensor 10.

[0037] After deployment, the mountain glacier basement water pressure and slip velocity measuring device, suitable for long-term observation, only requires a continuous power supply to transmit data to the surface for recording in real time, without the need for personnel supervision. During long-term observation, the water inside the ice borehole gradually freezes and closes the borehole, freezing the armored cable 1 inside the ice. The measuring device, located at the warm ice-rock interface, is always surrounded by meltwater when subglacial water systems are present, enabling long-term observation of subglacial water pressure.

[0038] When glacier slip occurs, the armored cable 1 frozen in the ice slips along with the entire glacier. At this time, the cable reel 14 will slowly rotate under the tension of the armored cable 1. Since the release speed of the armored cable 1 is consistent with the slip speed at the bottom of the glacier, the release speed of the armored cable 1 measured by the encoder 12 installed on one side of the cable reel 14 is the slip speed at the bottom of the glacier.

[0039] In the cold winter, the water system at the bottom of the glacier may freeze. At this time, the power supply of the heating plate 8 can be turned on so that the area around the measuring device is still in the meltwater environment, preventing the measuring device from being damaged by the excessive frost heave.

Claims

1. A device for measuring the basement water pressure and slip velocity of mountain glaciers suitable for long-term observation, characterized in that, include: The cable includes an armored cable (1), an upper spherical cover (2), a lower spherical body (4), a rubber sleeve (5), a retaining ring (6), a partition (7), a heating plate (8), a water pressure sensor (10), a friction screw (11), an encoder (12), a reel mounting plate (13), a cable reel (14), and a slip ring (15). The upper spherical cover (2) and the lower spherical body (4) are fixedly connected together to form a hollow sphere. The sphere is filled with low-temperature resistant silicone oil, and the density of the low-temperature resistant silicone oil is greater than that of water. Density, the upper spherical cover (2) has an axially penetrating central hole; the rubber sleeve (5) is installed in the central hole of the upper spherical cover (2); one end of the armored cable (1) passes through the rubber sleeve (5) and is wound on the cable reel (14), and is electrically connected to the slip ring (15), while the other end is connected to the surface power supply and signal acquisition equipment; a gap is left between the rubber sleeve (5) and the armored cable (1) for glacial water to enter the sphere; the partition (7) is coaxially arranged inside the sphere; the heating plate (8) The heating plate (8) and the partition plate (7) are both bonded to the lower surface of the partition plate (7). Both the heating plate (8) and the partition plate (7) have through holes evenly distributed. The through holes on the heating plate (8) and the through holes on the partition plate (7) are identical in shape and number and correspond one-to-one. The reel mounting plate (13) is fixed above the partition plate (7) by screws. The reel mounting plate (13) has a shaft hole. The two ends of the rotating shaft of the cable reel (14) are rotatably installed in the shaft hole of the reel mounting plate (13) by bearings. Friction bearings are installed on the top of the reel mounting plate (13). The screw (11) is used to adjust the clamping force of the friction screw (11) on the rotating shaft of the cable reel (14) by rotating the friction screw (11), thereby adjusting the rotational torque of the cable reel (14); the encoder (12) and the slip ring (15) are respectively installed at both ends of the rotating shaft of the cable reel (14); the water pressure sensor (10) is installed below the heating plate (8); the encoder (12), the heating plate (8) and the water pressure sensor (10) are electrically connected to the slip ring (15).

2. The measuring device for measuring the basement water pressure and slip velocity of mountain glaciers suitable for long-term observation according to claim 1, characterized in that: The armored cable (1) has a steel wire armor layer or a Kevlar fiber armor layer.

3. The measuring device for measuring the basement water pressure and slip velocity of mountain glaciers suitable for long-term observation according to claim 1, characterized in that: A limiting step is formed between the upper ball cover (2) and the lower ball (4), and the upper ball cover (2) and the lower ball (4) are fixed together by countersunk screws (3).

4. The measuring device for measuring the basement water pressure and slip velocity of mountain glaciers suitable for long-term observation according to claim 3, characterized in that: The inner surface of the lower sphere (4) has an inner step for placing the partition (7) and the heating plate (8). The fixing ring (6) is set on the inner wall of the lower sphere (4) and is used to press and fix the partition (7) and the heating plate (8).

5. The measuring device for measuring the basement water pressure and slip velocity of mountain glaciers suitable for long-term observation according to claim 4, characterized in that: The upper ball cover (2), the lower ball (4) and the fixing ring (6) are connected by countersunk screws (3).

6. The measuring device for measuring the basement water pressure and slip velocity of mountain glaciers suitable for long-term observation according to claim 1, characterized in that: The water pressure sensor (10) is installed below the heating plate (8) via a clamp (9), and the clamp (9), heating plate (8) and partition (7) are fixed together by screws.

Images