An experimental device and experimental method for simulating lithospheric flexural deformation

Abstract

The application discloses an experimental device and an experimental method for simulating flexural deformation of a lithosphere, and the experimental device comprises an experimental sand box and a tectonic deformation motion control device, experimental materials are laid in the experimental sand box, and an active push plate which can move up and down and left and right is arranged, the active push plate is connected with a driving device, and the driving device controls synchronous movement of the active push plate in horizontal and vertical directions to extrude the experimental materials. Different experimental materials can simulate different layers of the lithosphere, glycerol and sugar syrup can simulate a soft asthenosphere, different granular materials and a mixture of silica gel in different proportions can simulate the lithospheric mantle and a weak layer or a strong hard layer in the lithosphere, and the granular materials and the mixture can simulate the crust, so that tectonic physical simulation of flexural deformation of the lithosphere with different rheological structures is completed. The application realizes geological evolution processes caused by flexural deformation of the lithosphere, such as converging plate collision subduction, basin and mountain system evolution and formation of a foreland basin. The experimental method is simple, convenient to operate and wide in application range.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of tectonic physical simulation experimental device and experimental method, more particularly to a kind of tectonic deformation physical simulation device and method under the control of lithospheric flexural deformation. BACKGROUND

[0002] Lithospheric flexural deformation refers to the absorption of external force by the lithosphere in the geological time scale (> 10 5 yr), and the lithosphere can recover to the initial state when the external force is unloaded. Lithospheric flexural deformation is widely developed in continental orogenic belt foreland basin, subduction trench and other geological environments. It is of great significance to explain the geometry of continental sedimentary basin and plate subduction, the distribution of earthquakes in subduction zone, and postglacial rebound and other geological phenomena. Tectonic deformation physical simulation experiment is a method that can simulate large-scale geological tectonic deformation in the laboratory, and has wide applicability. Since the 1980s, the establishment of lithospheric scale tectonic physical simulation experiment, in recent decades, scholars at home and abroad have carried out physical simulation of lithospheric plate deformation, and have made important progress in the research fields of rift extension, collision and subduction deformation. Therefore, the use of tectonic physical simulation to study lithospheric flexural deformation has important scientific significance for explaining related geological scientific problems.

[0003] The degree of lithospheric flexural deformation is represented by the effective elastic thickness of the lithosphere, and the most important control factor is the rheological structure of the lithosphere in profile. However, the current model design in the lithospheric scale tectonic physical simulation experiment at home and abroad is simple, which cannot meet the complex rheological structure of the lithosphere in profile in actual geological conditions. The experimental device can only simulate horizontal compression, which does not conform to the vertical bending deformation in the process of lithospheric flexural deformation. Therefore, the existing tectonic physical simulation experiment method and device are difficult to simulate the influence of the difference of different lithospheric rheological structures on lithospheric flexural deformation. SUMMARY

[0004] The first purpose of the present application is to provide a lithospheric flexural deformation physical simulation experiment device that can fully consider the difference of different plate rheological structures, and the second purpose of the present application is to provide a simulation experiment method using the device, to help researchers complete the geological tectonic processes such as collision and subduction, and basin and mountain system evolution under the control of lithospheric flexure in the laboratory.

[0005] Technical solution: The experimental device for simulating the flexural deformation of the lithosphere comprises an experimental sand box and a tectonic deformation motion control device; the experimental sand box is internally provided with an experimental model, which comprises a crust, a lithospheric mantle and a soft flow layer in the longitudinal direction; the simulation materials used in each layer can be adjusted according to the rheological structure of different lithospheres; the tectonic deformation motion control device comprises a movable push plate for extruding the experimental model, a horizontal extrusion mechanism for pushing the movable push plate, a driving device for synchronous movement of the vertical lifting mechanism, and a device for realizing the flexural deformation of the lithosphere.

[0006] Further, the experimental model comprises two plates or a plurality of plates in the transverse direction.

[0007] Further, the horizontal extrusion mechanism and the vertical lifting mechanism for pushing the movable push plate are driven by hydraulic cylinders.

[0008] Further, the driving device comprises a horizontal hydraulic cylinder, a vertical hydraulic cylinder, a first translation connecting plate, a first lifting slide rail, a first lifting slide block, and a translation slide rail; the first lifting slide block is fixedly connected to the movable push plate through the translation slide rail; the first translation connecting plate is fixedly connected to the movable push plate; the vertical hydraulic cylinder and the horizontal hydraulic cylinder drive the movable push plate to move along the first lifting slide rail and the translation slide rail to realize the extrusion of the experimental material.

[0009] Further, the horizontal extrusion mechanism and the vertical lifting mechanism move synchronously, and the speed of the vertical hydraulic cylinder and the horizontal hydraulic cylinder can be adjusted individually to control the angle of the flexure of the lithosphere.

[0010] Further, the lifting mechanism comprises a second lifting slide block and a second lifting slide rail; the movable push plate is fixedly connected to the second lifting slide rail; when the movable push plate moves for extrusion, the horizontal hydraulic cylinder moves along the second lifting slide rail through the second lifting slide block for adjustment.

[0011] Further, the experimental sand box and the vertical hydraulic cylinder are fixed on the experimental table through a support mechanism; the horizontal hydraulic cylinder is fixed on the experimental table through a support mechanism; and the experimental table is fixed on the ground through a rack fixing mechanism.

[0012] Further, the inside top end and the inner wall of the experimental sand box are provided with an image acquisition device and a three-dimensional terrain scanner.

[0013] An experimental method using the experimental device for simulating the flexural deformation of the lithosphere as described above, characterized by comprising the following steps:

[0014] S1: Based on the tectonic background of the flexural deformation of the lithosphere, the rheological characteristics of each layer in the lithospheric profile are analyzed by using geophysics, geology and mineral physics, and a rheological structure model of the research area is established.

[0015] S2: According to the rheological structure model of the research area and the similarity principle of the tectonic physical simulation, an experimental model is established, and the experimental materials of each layer of the lithosphere in the simulation experiment are determined.

[0016] S3: Then, the movable push plate is adjusted to a proper height through the lifting device. Then, glycerol is poured into the experimental box first to simulate the asthenosphere, and then the lithospheric mantle and the crust are laid in sequence.

[0017] S4: The experimental control terminal and the experimental control cabinet are opened, and the horizontal hydraulic cylinder and the vertical hydraulic cylinder are started. During the operation, the high-resolution camera and the three-dimensional terrain scanner are used to record the deformation process of the model plane and section, and the data are observed and collected.

[0018] Further, the simulation materials of each layer in the experimental model are selected according to the rheological structure of different lithospheres. The simulation material of the asthenosphere is glycerol, syrup and honey. The simulation material of the lithospheric mantle is a mixture of silica gel and granular material, and the mixing ratio is changed according to the rheological structure of different lithospheres. The simulation material of the crust is brittle granular material and its mixture. When there is a weak lower crust in the continental lithosphere, the simulation material is a mixture of silica gel and granular material.

[0019] Beneficial effects: Compared with the prior art, the experimental model is divided into the crust, the lithospheric mantle and the asthenosphere in the section. By changing the experimental materials and the mixing ratio, different rheological structure models of the lithosphere, that is, plates with different effective elastic thicknesses, can be simulated. Therefore, the phenomena observed and the data collected during the experiment can be used to study the deflection deformation caused by the lithosphere with different rheological structures, and the tectonic processes such as collision subduction and basin and mountain system evolution can be studied in detail. The experimental device and the experimental method of the present application are not limited to the study of the deflection deformation of the lithosphere, but can also simulate the deformation of the continental lithosphere with complex rheological structures such as weak zones or strong hard zones. The experimental device structure is simple and cost-saving. BRIEF DESCRIPTION OF DRAWINGS

[0020] Fig. 1 It is a side view of the experimental device of the present application;

[0021] Fig. 2 It is a top view of the experimental device of the present application;

[0022] Fig. 3 It is a right view of the experimental sand box of the present application. DETAILED DESCRIPTION

[0023] The technical solutions of the present application will be further described below in combination with embodiments.

[0024] For example, Figs. 1-3As shown, the experimental device for simulating the flexural deformation of the lithosphere of the present application comprises an experimental sand box 1 and a tectonic deformation motion control device. The experimental sand box 1 is laid with an experimental model, and the lithosphere experimental model comprises a crust 6, a lithospheric mantle 5 and a soft flow zone 4. By changing the experimental materials of different layers in the experimental model, different rheological structure models of the lithosphere are simulated. The horizontal hydraulic cylinder 2 and the vertical hydraulic cylinder 16 are synchronously moved to drive the movable push plate 12 to extrude the experimental materials forward, so that the flexural deformation of the lithosphere can be completed, and the influence of the inhomogeneous rheological properties on the tectonic deformation of the lithosphere in the same plate can also be simulated, such as the influence of the weak zone and the hard zone in the plate on the deformation of the land.

[0025] The experimental sand box 1 is fixed on the experimental bench 3 through the support mechanism 7, and the experimental bench 3 is fixed on the floor through the bench fixing mechanism 10. The movable push plate 12 is arranged on one side of the experimental sand box 1, and the movable push plate 12 is fixed on the first translation connecting plate 11 on one side, the first translation connecting plate 11 is fixed on the vertical hydraulic cylinder 16, the movable push plate 12 is connected with the translation sliding rail 17 on the other side, the other end of the translation sliding rail 17 is connected with the second translation connecting plate 14, the second translation connecting plate 14 is fixed on the first lifting sliding block 9, and the first lifting sliding block 9 can move up and down on the first lifting sliding rail 8. When the vertical hydraulic cylinder 16 and the horizontal hydraulic cylinder 2 synchronously control the movable push plate 12 to extrude the experimental materials, the movable push plate 12 can be driven to move up and down along the first lifting sliding rail 8, and the movable push plate 12 can be adjusted to move horizontally along the translation sliding rail 17. When the movable push plate 12 extrudes the experimental materials, the horizontal hydraulic cylinder 2 is moved along the second lifting sliding rail 15 through the second lifting sliding block 18 by using the lifting device. The image acquisition device is installed on the top and side of the experimental box.

[0026] The tectonic deformation motion control device is connected with the computer installed with the experimental sand box control software, and the distance, speed and time required for the horizontal hydraulic cylinder and the vertical hydraulic cylinder to control the movable push plate 12 during the experiment are set in the experimental sand box control software, so as to control the movable push plate 12 to extrude the experimental materials.

[0027] Experimental principle:

[0028] By using the tectonic physical simulation motion control device and the rheological properties of different experimental materials, the flexural deformation process of the lithosphere caused by different rheological structures of the lithosphere is simulated. The rheological structure of the lithosphere under different geological backgrounds is different, that is, the effective elastic thickness of the plate is different, so that the geological evolution processes caused by the flexural deformation of the lithosphere, such as lithospheric collision and subduction and basin and mountain system evolution, are realized.

[0029] Experimental method:

[0030] Before the experiment, firstly, the flexural deformation of the lithosphere in the study area is analyzed, and the rheological characteristics of each layer on the lithospheric profile are analyzed by using geophysics, geology and mineral physics, and a rheological structure model of the study area is established.

[0031] Then, according to the similarity principle of structural physical simulation experiment, different experimental materials and proportions are selected to simulate different layers of the lithosphere. Glycerol, syrup, honey, etc. can be used to simulate the asthenosphere, low-viscosity silica gel and particle material mixture can be used to simulate the weak layer in the weak lithosphere, high-viscosity silica gel and particle material mixture can be used to simulate the strong layer in the strong lithosphere, the mixing ratio can be changed according to the rheological properties of different layers in the lithosphere, quartz sand, feldspar sand, silica powder and their mixtures can be used to simulate the crust, the vertical and horizontal hydraulic cylinders are connected with the movable push plate, the movable push plate is adjusted to the appropriate height, and the experimental materials such as soft flow layer, lithospheric mantle and crust are laid in the experimental sand box in turn, and the experimental preparation work is completed.

[0032] Start the horizontal and vertical hydraulic cylinders to move synchronously, and drive the movable push plate to extrude the experimental materials. During the experiment, high-resolution cameras and three-dimensional terrain scanners are used to record the deformation process of the plane and profile. After the experiment, quantitative analysis can be carried out according to the data of photography and scanning, and the experimental results can be compared with the geological model to further study the flexural deformation and evolution of the lithosphere.

Claims

1. An experimental apparatus for simulating the flexural deformation of the lithosphere, characterized by: The experimental sand box and the tectonic deformation motion control device are included; the experimental model is laid in the experimental sand box (1), and the experimental model includes the crust (6), the lithospheric mantle (5) and the soft flow core (4) in the longitudinal direction; the simulation materials used by each layer can be adjusted according to the rheological structure of different lithospheric mantle; the tectonic deformation motion control device includes the movable push plate (12) for extruding the experimental model and the driving device, the driving device includes the horizontal hydraulic cylinder (2), the vertical hydraulic cylinder (16), the first translation connecting plate (11), the first lifting slide rail (8), the first lifting sliding block (9) and the translation slide rail (17); one side of the movable push plate (12) is on the first translation connecting plate (11), the first translation connecting plate (11) is fixed on the vertical hydraulic cylinder (16), the other side of the movable push plate (12) is connected with the translation slide rail (17), the other end of the translation slide rail (17) is connected with the second translation connecting plate (14), the second translation connecting plate (14) is fixed on the first lifting sliding block (9), the first lifting sliding block (9) can make lifting movement on the first lifting slide rail (8), when the vertical hydraulic cylinder (16) and the horizontal hydraulic cylinder (2) control the movable push plate (12) to extrude the experimental material synchronously, the movable push plate (12) makes lifting movement along the first lifting slide rail (8) and makes translation movement adjustment along the translation slide rail (17) at the same time; the movable push plate (12) is fixedly connected with the second lifting slide rail (15), when the movable push plate (12) makes extrusion movement, the horizontal hydraulic cylinder (2) moves along the second lifting slide rail (15) through the second lifting sliding block (18) for adjustment; the speed of the vertical hydraulic cylinder (16) and the horizontal hydraulic cylinder (2) can be adjusted individually.

2. The experimental device for simulating the deformation of the lithospheric flexure according to claim 1, characterized in that: The experimental model includes two plates or multiple plates in the lateral direction.

3. The experimental device for simulating the deformation of the lithospheric flexure according to claim 1, characterized in that: The experimental sand box (1) and the vertical hydraulic cylinder (16) are fixed on the experimental table (3) through the first support mechanism (7), the horizontal hydraulic cylinder (2) is fixed on the experimental table (3) through the second support mechanism (13), and the experimental table (3) is fixed on the ground through the rack fixing mechanism (10).

4. The experimental device for simulating the deformation of the lithospheric flexure according to claim 1, characterized in that: The inside top end and the inner wall of the experimental sand box (1) are provided with the image acquisition device and the three-dimensional terrain scanner.

5. The experimental device for simulating the deformation of the lithospheric flexure according to claim 1, wherein, The simulation material of the soft flow core (4) is glycerol, syrup or honey; the simulation material of the lithospheric mantle (5) is the mixture of silica gel and granular material, and the mixing ratio is changed according to the rheological structure of different lithospheric mantle; the simulation material of the crust (6) is brittle granular material and its mixture, and when the weak lower crust exists in the continental lithospheric mantle, the simulation material is the mixture of silica gel and granular material.

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