Composition for preparing a seismic physical model, seismic physical model and method for preparing the same

Abstract

The present invention discloses a composition for preparing an earthquake physical model, an earthquake physical model, and a preparation method thereof. The composition for preparing an earthquake physical model is characterized in that, in parts by weight, it comprises 100 parts by weight of an epoxy resin, 50 parts by weight of a curing agent, and 1-100 parts by weight of nano-mica powder. The present invention can prepare a physical model material with a longitudinal and transverse wave velocity ratio lower than 2.2 and a distribution range between 1.91 and 2.19 by doping the epoxy resin with nano-mica powder in different proportions. This reduces the longitudinal and transverse wave velocity ratios of the physical model material to a limited extent, improves the similarity with the actual formation velocity, and can greatly expand the application space of earthquake physical simulation technology.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of geophysical exploration, and particularly relates to a composition for preparing a seismic physical model, a seismic physical model and a preparation method thereof. BACKGROUND

[0002] Seismic physical simulation is a method of making a geological model in a laboratory according to a scale reduction of field geological structure and geological body, and using ultrasonic waves to simulate seismic waves to perform forward simulation of field seismic exploration. In the 1950s, with the development of ultrasonic technology, a seismic simulation experiment system began to be established. The United States and the Soviet Union have successfully conducted seismic experiments using ultrasonic technology. Subsequently, China has also gradually established its own seismic simulation laboratory. With the continuous deepening of oil and gas exploration and development work, the exploration objects and development environments are becoming more and more complex, the exploration difficulty is becoming greater and greater, and the refinement requirement of exploration results is becoming higher and higher, which means that there are higher requirements for the physical model materials.

[0003] At present, domestic colleges and institutes mainly use the method of epoxy resin casting to prepare physical models. Epoxy resin has high bonding strength, is non-toxic and has low cost, and meets the needs of high-speed strata, so it is widely used. Among them, the propagation speed of longitudinal wave in epoxy resin is about 2600 m / s, and the propagation speed of transverse wave is about 1100 m / s. With the change of simulation target to deep and ultra-deep layers, the actual longitudinal wave speed of the stratum can reach 6400 m / s, and the transverse wave speed can reach 3000 m / s. Even if the model is made according to the speed ratio of 1:2, the wave speed of epoxy resin cannot meet the requirements. In order to improve the longitudinal and transverse wave speeds of the physical model, fillers such as talc powder are often added to the epoxy resin. Although the longitudinal wave speed can be increased from about 2600 m / s to about 3100 m / s, the transverse wave speed does not increase significantly after adding fillers. In addition, the actual longitudinal and transverse wave speed ratio of the stratum is between 1.6 and 2.0, while the longitudinal and transverse wave speed ratio of the current physical model material is often greater than 2.2, which is quite different from the actual value. In physical simulation, the longitudinal and transverse wave speed ratio is a very important parameter, which can determine the AVO characteristics of the reservoir. Therefore, obtaining a model material close to the actual longitudinal and transverse wave speed ratio of the stratum can not only improve the accuracy of simulation, but also greatly expand the application space of seismic physical simulation technology. SUMMARY

[0004] In order to solve the problems in the prior art, the present application provides a composition for preparing a seismic physical model, a seismic physical model and a preparation method thereof.

[0005] The inventors of the present application found that by doping different proportions of nano-mica powder in epoxy resin, a physical model material with a ratio of longitudinal wave speed to transverse wave speed lower than 2.2 and a distribution range of 1.91 to 2.19 can be prepared, effectively reducing the ratio of longitudinal wave speed to transverse wave speed of the physical model material, improving the similarity with the actual formation velocity ratio, and greatly expanding the application space of seismic physical simulation technology.

[0006] In a first aspect, the present application provides a composition for preparing a seismic physical model.

[0007] As a specific embodiment, the composition for preparing a seismic physical model comprises, by weight, 100 parts by weight of epoxy resin, 50 parts by weight of curing agent, and 1-100 parts by weight of nano-mica powder.

[0008] Mica powder is a layered structure silicate with good adhesion and dispersibility, and is widely used in many fields. Compared with traditional modified materials, the use of nano-mica powder to dope and modify epoxy resin significantly reduces the ratio of longitudinal wave speed to transverse wave speed of the physical model material, improves the similarity with the actual formation, and expands the application space of seismic physical simulation technology.

[0009] Preferably, the composition comprises 100 parts by weight of epoxy resin, 50 parts by weight of curing agent, and 5-40 parts by weight of nano-mica powder.

[0010] Preferably, the viscosity of the epoxy resin ranges from 11000 to 14000 mPas; and / or

[0011] The curing agent is an R-2269 type curing agent.

[0012] Preferably, the R-2269 type curing agent comprises isophorone diamine 50-60 wt.%, benzyl alcohol 20-25 wt.% and epoxy resin 20-25 wt.%.

[0013] In a second aspect, the present application provides a seismic physical model formed using the composition of the first aspect.

[0014] Preferably, the ratio of longitudinal wave speed to transverse wave speed of the seismic physical model ranges from 1.91 to 2.19.

[0015] In a third aspect, the present application provides a method for preparing a seismic physical model.

[0016] As a specific embodiment, the method comprises the following steps:

[0017] 2) Mix the epoxy resin, the nano-mica powder and the R-2269 type curing agent, inject into the mold of step 1), and cure and demold.

[0018] Preferably, the following step is performed before step 2):

[0019] 1) Apply silicone rubber as a release coating on the surface of the mold, and cure and dry the coating.

[0020] Preferably, the epoxy resin is preheated before mixing in step 2), preferably at a temperature of 30-60°C for 0.5-2 hours; and / or

[0021] After mixing in step 2), the mixed material is vacuumed to remove air bubbles therefrom, preferably for a duration of 10 minutes.

[0022] Effects of the present application

[0023] The present application can prepare a physical model material with a ratio of P-wave velocity to S-wave velocity lower than 2.2 and a distribution range of 1.91 to 2.19 by doping different proportions of nano-mica powder in the epoxy resin, thereby reducing the ratio of P-wave velocity to S-wave velocity of the physical model material, improving the similarity to the actual formation velocity, and greatly expanding the application space of seismic physical simulation technology. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 Figure for the relationship between the P-wave velocity of the physical model material of the present application and the content of nano-mica powder.

[0025] Figure 2 Figure for the relationship between the S-wave velocity of the physical model material of the present application and the content of nano-mica powder.

[0026] Figure 3 Figure for the relationship between the ratio of P-wave velocity to S-wave velocity of the physical model material of the present application and the content of nano-mica powder. DETAILED DESCRIPTION

[0027] The embodiments of the present application will be described in detail below with reference to the examples, which facilitate better understanding of the present application, but do not limit the present application. The raw materials or components used in the present application can be obtained by market channels or conventional methods.

[0028] 1. Mold pretreatment

[0029] After the mold is made, a layer of silicone rubber material is applied as a release coating on the inner surface of the mold. After the coating is cured, the treated mold is placed in a dry and ventilated place for standby.

[0030] 2. Material pretreatment

[0031] To facilitate the stirring and mixing of the skeleton material and the powder filler, the epoxy resin can be preheated in a 50°C oven for 1 hour to reduce the fluid viscosity.

[0032] 3. Material configuration

[0033] The required materials are weighed according to the requirements of the formula, a certain amount of nano-mica powder is added to the epoxy resin and stirred until uniform, then the curing agent is added and stirred until uniform.

[0034] 4. Model pouring

[0035] The prepared material is vacuumed to remove air bubbles in the fluid, and after 10 minutes of vacuum treatment, it is poured into a standby mold and placed in a flat place to cure the model.

[0036] 5. Curing and demolding

[0037] After the model material is completely cured, the mold can be removed, and the curing time is determined by the room temperature and the size of the model.

[0038] The ingredients and amounts of the compositions in the comparative example and each example, and the longitudinal wave velocity, transverse wave velocity, and longitudinal-to-transverse wave velocity ratio data of the physical models prepared are shown in Table 1.

[0039] Table 1

[0040]

[0041] wherein EP represents an epoxy resin, R-2269 represents a R-2269 type curing agent, Vp represents the longitudinal wave velocity, Vs represents the transverse wave velocity, and Vp / Vs represents the longitudinal-to-transverse wave velocity ratio.

[0042] In this embodiment, the viscosity of the epoxy resin is 12000 mPas, and the curing agent is a R-2269 type curing agent, which includes isophorone diamine 50-60 wt.%, benzyl alcohol 20-25 wt.% and epoxy resin 20-25 wt.%.

[0043] As can be seen from the table, the epoxy resin doped with different proportions of nano-mica powder according to the present application can prepare a physical model material with a longitudinal-to-transverse wave velocity ratio of less than 2.2 and a distribution range of 1.91 to 2.19, which reduces the longitudinal-to-transverse wave velocity ratio of the physical model material and improves the similarity with the actual formation velocity, greatly expanding the application space of seismic physical simulation technology.

[0044] Any numerical values recited herein include all values from the lower value and up to the upper value. Values that are recited herein also include values that are "framed" by the recited values. For example, if a concentration range is stated as 1% to 50%, it is intended that values such as 25%, 30%, and 35% are expressly enumerated. All integer values are used "open ended" such that "50%" really means "50% to 50%". The same principle applies to ranges recited as being "between" two values. Discrete, non-integer values can be assumed within the stated ranges. These are only a few of the specific examples that are given. In the application, all possible combinations of numerical values between the lowest value and the highest value enumerated, are to be considered to be expressly stated in this application.

[0045] It is to be understood that the embodiments described above are merely illustrative of the application and do not limit the scope of the application. The application has been described with reference to the example embodiments thereof while the words used are words of description necessary to provide a practical teaching of the application. It is to be understood that no limitation of the scope of the application is thereby intended. Such descriptions used are used only to provide one or more practical examples of the application and to exemplify the best mode of practicing the application in its specific aspects. It is to be understood that the application is not limited to particular embodiments described, and is intended to cover any and all alternatives, modifications, variations, improvements and / or adaptations thereof. Although the application has been described with reference to particular methods, materials and embodiments, it is not intended to be limited to the particulars disclosed herein; rather it extends to all functionally equivalent structures, methods and uses.

Claims

1. Use of the composition for forming an earthquake physical model, characterized in that: In parts by weight, the composition comprises 100 parts by weight of epoxy resin, 50 parts by weight of curing agent and 1-100 parts by weight of nano-mica powder; The longitudinal and transverse wave velocity ratios of the earthquake physics model range from 1.91 to 2.

19.

2. The use according to claim 1, characterized in that The composition comprises 100 parts by weight of epoxy resin, 50 parts by weight of curing agent and 5-40 parts by weight of nano-mica powder.

3. The use according to claim 1 or 2, characterized in that The epoxy resin has a viscosity in the range of 11000-14000 mPas; and / or The curing agent is R-2269 curing agent.

4. The use according to claim 3, characterized in that The R-2269 curing agent includes 50-60 wt.% of isophorone diamine, 20-25 wt.% of benzyl alcohol and 20-25 wt.% of epoxy resin.

5. The use according to claim 1 or 2, characterized in that: The method for preparing the earthquake physical model comprises the following steps: 2) Mix epoxy resin, nano-mica powder and curing agent, inject into the mold, cure and demould.

6. The use according to claim 5, characterized in that Before step 2), perform the following steps: 1) Apply silicone rubber as a release coating on the mold surface and allow the coating to cure and dry.

7. The use according to claim 5, characterized in that Before mixing in step 2), preheating the epoxy resin; and / or After mixing in step 2), the mixed material is vacuumed to remove air bubbles.

8. The use according to claim 7, characterized in that The preheating temperature is 30-60°C and the preheating time is 0.5-2 hours; and / or The vacuuming time is 10 minutes.

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