CN105484739A - Carbonate rock formation pore pressure testing method and device - Google Patents

Abstract

The invention discloses a method and a device for testing the pore pressure of a carbonate formation. In this method, under the conditions of fixed temperature and confining pressure and changing pore pressure, different fractured-cavity carbonate rock models are tested by sound waves, and when different pore pressures are obtained, the axial The standard curve cluster formed by the relationship between stress, shear wave, and longitudinal wave; then obtain the measurement curve of the relationship between the axial stress, shear wave, and longitudinal wave of the actual carbonate formation; compare the measurement curve with the standard curve cluster, The formation pore pressure of the fractured-cavity carbonate model corresponding to the curve closest to the measured curve in the standard curve cluster is determined to be the pore pressure of the actual carbonate formation. The method utilizes the test data of different fracture-cavity carbonate rock models and the acoustic logging data of the carbonate rock formation, and the actual formation pore pressure of the carbonate rock can be obtained from the chart. The device enables the automation of the method.

Description

Carbonate formation pore pressure testing method and device

technical field

The present invention relates to the technical field of methods or equipment specially used for drilling deep complex carbonate rocks or fracture-cavity formations in order to obtain the acoustic-mechanical response characteristics of fracture-cavity carbonate rocks, in particular to a carbonate rock formation Pore pressure testing method and apparatus.

Background technique

Worldwide, carbonate reservoirs account for 52% of proven oil reserves and 60% of total oil and gas production. At present, the marine carbonate formations in the major blocks in my country are dominated by fracture-cavity reservoirs of carbonate rocks, with strong lithology heterogeneity, well-developed fractures and caves, coexistence of deep oil and gas reservoirs and multi-pressure systems, and drilling geological environmental factors. It is difficult to identify, easy to leak, and serious damage to the reservoir. One of the main reasons for the accident is that the pore pressure of the carbonate rock formation cannot be accurately determined, which seriously restricts the strength of my country's oil exploration and development.

The development of fractures, dissolved pores, and dissolved caves in marine carbonate rocks, the complex characteristics of formation pore pressure and stress distribution, such as great differences, poor regularity, and strong uncertainty, lead to poor quality of geophysical prospecting and seismic data. It is difficult to accurately identify and predict the rock mass mechanical characteristic parameters and formation pressure system, and the predictability in the drilling process is poor, resulting in a low success rate in the drilling process, which seriously restricts the process of oil and gas exploration and development.

At present, the "sedimentary compaction theory" of clastic rocks is used, and most of them use acoustic wave velocity and geophysical data to predict formation pressure, but no substantial breakthrough has been made in theory.

To predict the pore pressure of fractured-vuggy carbonate formations, the acoustic and mechanical response characteristics of the simulated fractured-vuggy carbonate rocks are analyzed indoors. The individual differences of fractured-vuggy carbonate rocks in the original formation are huge, and it is difficult to Describe the structure of cracks and pores in detail. A better method to study the acoustic and mechanical response characteristics of fractured-cavity carbonate rocks is to use artificially prepared samples to simulate different fracture and pore characteristics.

At present, the following problems exist in the use of natural fractured-cavity carbonate rocks:

Due to the complex environment during the deposition of fractured carbonate rocks and multiple tectonic movements, the differences between the samples taken are huge, and the distribution of internal fractures and the degree of pore development are difficult to grasp. Testing is expensive and difficult to bear. If the original rock samples are used to test the characteristics of acoustic and mechanical responses, the comparability of test results will be greatly reduced, which is not conducive to the summary and analysis of regularity.

To sum up, there are many insurmountable congenital deficiencies in using natural carbonate rock samples for testing, and it is difficult to grasp the accuracy of the test results.

Contents of the invention

In view of this, the present invention provides a method and device for testing the pore pressure of carbonate rock formations, the method utilizes the test data of different fracture-cavity carbonate rock models, and, the sonic logging data of carbonate rock formations, The actual formation pore pressure of carbonate rock can be obtained from the chart, and the test accuracy is high.

In order to achieve the above-mentioned first object, the technical scheme of the carbonate formation pore pressure testing method provided by the present invention is as follows:

The carbonate formation pore pressure testing method provided by the invention comprises the following steps:

Prepare different models of fractured-cavity carbonate rocks;

The different fracture-cavity carbonate rock models are respectively placed in the rock mechanics testing machine;

Under the condition that the temperature and confining pressure are fixed and the pore pressure changes, the different fractured-cavity carbonate rock models are tested by sound waves, and when different pore pressures are obtained, each of the fractured-cavity carbonate rock models The standard curve cluster composed of the relationship among axial stress, shear wave and longitudinal wave;

Obtain the measurement curve of the relationship between the axial stress, shear wave and longitudinal wave of the actual carbonate formation by using the acoustic logging data of the carbonate formation;

Comparing the measurement curve with the standard curve cluster, it is determined that the formation pore pressure of the fractured-cavity carbonate rock model corresponding to the curve closest to the measurement curve in the standard curve cluster is the actual carbon Pore pressure in salt rock formations.

The method for testing the pore pressure of carbonate formations provided by the present invention can also be further realized by adopting the following technical measures.

Preferably, the relationship between the axial stress, the transverse wave and the longitudinal wave includes the relationship between the axial stress and the transverse wave, and/or the relationship between the axial stress and the longitudinal wave, and/or the relationship between the transverse wave and the longitudinal wave relationship between.

Preferably, for the same pore pressure condition of the same fractured-cavity carbonate model, the standard curve of the relationship between the axial stress, shear wave and longitudinal wave of the fracture-cavity carbonate model is plotted in the same chart.

As preferably, for different pore pressure conditions of the same fracture-cavity carbonate rock model, the standard curve of the relationship between the axial stress, shear wave and longitudinal wave of the fracture-cavity carbonate rock model is drawn in the same chart, The different pore pressure conditions are distinguished by different legends.

As preferably, for the same pore pressure condition of different fracture-cavity carbonate rock models, the standard curve of the relationship between the axial stress, shear wave and longitudinal wave of the fracture-cavity carbonate rock model is drawn in the same chart, The different fractured-cavity carbonate rock models are distinguished by different legends.

Preferably, in the same graph, the axial stress is the abscissa, the transverse wave is the first ordinate, and the longitudinal wave is the second ordinate.

Preferably, the pore pressure, axial stress, shear wave, and longitudinal wave data are collected by a data acquisition module; and/or, the standard curve cluster is drawn by a curve drawing module; and/or, the The comparison between the measurement curve and the standard curve cluster is obtained by comparison with the comparison module; and/or, the fracture-cavity carbonate rock model corresponding to the curve closest to the measurement curve in the standard curve cluster is identified The formation pore pressure is the pore pressure of the actual carbonate rock formation, which is obtained through the judgment module.

Preferably, the fractured-cavity carbonate rock model is a standard sample, and the diameter of the standard sample is 50mm and the height is 100mm.

Preferably, the fractured-cavity carbonate rock model includes aggregate, hole simulation parts, and rock mass crack simulation parts;

The mass and number ratio of each component of the aggregate is: cement: quartz sand: barite powder: water=(2～3): (1.5～2.5): (0.5～1): (0.4～1);

The hole simulation parts are distributed in the aggregate;

The rock mass crack simulator is also distributed in the aggregate.

Preferably, the rock mass crack simulation piece is sulfuric acid paper, or sketch paper.

Preferably, the hole simulation part is spherical.

Preferably, the spherical objects are polystyrene particles with different particle sizes.

As preferably, it is characterized in that, comprising the following steps:

filling the aggregate, hole simulation parts, and rock mass crack simulation parts in a mold according to the distribution law;

Standing for a predetermined time under predetermined temperature and humidity conditions, so that physical and chemical reactions between the aggregates can fully occur;

The mold is removed to obtain the fractured-cavity carbonate rock model.

Preferably, before the step of filling the aggregate, hole simulation piece and rock mass crack simulation piece in a mold according to the distribution law, it also includes the step of brushing lubricant on the inner wall of the mold.

As preferably, filling the aggregate, the hole simulation piece, and the rock mass crack simulation piece in a mold according to the distribution law includes the following steps:

preparing the aggregate and hole simulation parts, and fully stirring the aggregate and hole simulation parts, so that the aggregate and hole simulation parts form a mixture;

Adding the mixture into the mold in layers;

The crack simulator is added between the layers of the mix.

Preferably, when adding the mixture into the mold in layers, after the addition of each layer of the mixture is completed, a step of tamping the added mixture is also included.

Preferably, after the step of compacting the added mixture is completed, the step of roughening is also included.

Preferably, the step of adding the mixture into the mold in layers is realized by paving the mixture in the mold.

Preferably, after the step of filling the aggregate, hole simulation piece and rock mass crack simulation piece in a mold according to the distribution law, the step of scraping the mixture beyond the opening surface of the mold is also included.

Preferably, after the step of scraping off the mixture beyond the opening surface of the model is completed, a step of smoothing is also included.

Preferably, after the leveling step is completed, a compacting step is further included, and after the compacting step, the exposed mixture forms a flat surface.

In order to achieve the above-mentioned second purpose, the technical scheme of the carbonate formation pore pressure testing device provided by the present invention is as follows:

The carbonate formation pore pressure testing device provided by the present invention includes a rock mechanics testing machine, a data acquisition module, a curve drawing module, a comparison module, and a judgment module,

The rock mechanics testing machine is used to load different fracture-cavity carbonate rock models, and provides test conditions for temperature, confining pressure fixed, and pore pressure change;

The data acquisition module is used to obtain the axial stress, shear wave, and longitudinal wave test data of each of the fractured-cavity carbonate rock models at different pore pressures; and, acoustic logging data of carbonate rock formations;

When the curve drawing module is used to draw different pore pressures, a standard curve cluster composed of the relationship between the axial stress, shear wave, and longitudinal wave of each of the fractured-cavity carbonate rock models; and, the actual carbonate The measurement curve of the relationship between the axial stress, shear wave and longitudinal wave of the rock formation;

The comparison module is used to compare the measurement curve with the standard curve cluster, and obtain the closeness between the measurement curve and each curve in the standard curve cluster;

According to the proximity, the judging module determines that the formation pore pressure of the fractured-cavity carbonate model corresponding to the curve closest to the measurement curve in the standard curve cluster is the actual carbonate formation. pore pressure.

The carbonate formation pore pressure testing device provided by the present invention can also be further realized by adopting the following technical measures.

Preferably, the closeness includes numerical closeness, and trend closeness.

The method for testing the pore pressure of carbonate formations provided by the present invention firstly prepares different models of fracture-cavity carbonate rocks; Experiment, drawing a standard curve cluster composed of the relationship between the axial stress, shear wave and longitudinal wave of each fractured-cavity carbonate rock model; The curves in the cluster are compared; finally, the actual formation pore pressure of carbonate rock is obtained. The method utilizes the test data of different fracture-cavity carbonate rock models and the acoustic logging data of the carbonate rock formation, and the actual formation pore pressure of the carbonate rock can be obtained from the chart.

The carbonate formation pore pressure testing device provided by the present invention is based on the carbonate formation pore pressure testing method provided by the present invention, and data collection, curve drawing, proximity comparison, and pore pressure identification are all automatically realized by computer , not only the work efficiency is higher, but also the error of human operation and comparison can be eliminated.

Description of drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiment. The drawings are only for the purpose of illustrating a preferred embodiment and are not to be considered as limiting the invention. Also throughout the drawings, the same reference numerals are used to designate the same components. In the attached picture:

Fig. 1 is the flow chart of the steps of the carbonate formation pore pressure testing method that the embodiment of the present invention 1 provides;

Fig. 2 is a flow chart of the steps of the preparation method of the fractured-cavity carbonate rock model applied in the carbonate formation pore pressure testing method provided by the embodiment of the present invention 23;

Fig. 3 is the flow chart of the steps of the preparation method of the fractured-cavity carbonate rock model applied in the carbonate formation pore pressure testing method provided by the embodiment of the present invention 24;

Fig. 4 is a schematic diagram of the signal flow of the carbonate formation pore pressure testing device provided by Embodiment 26 of the present invention.

detailed description

In order to solve the problems existing in the prior art, the invention provides a method and device for testing the pore pressure of carbonate formations.

In order to further explain the technical means and effects of the present invention to achieve the intended purpose of the invention, the following in conjunction with the accompanying drawings and preferred embodiments, the specific implementation of the carbonate rock formation pore pressure testing method and device proposed according to the present invention Mode, structure, feature and effect thereof are as follows in detail. In the following description, different "one embodiment" or "embodiment" do not necessarily refer to the same embodiment. Furthermore, the particular features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.

The term "and/or" in this article is just an association relationship describing associated objects, which means that there can be three relationships, for example, A and/or B. The specific understanding is: A and B can be included at the same time, and A and B can be included separately. A exists, B may exist alone, and any of the above three situations can be met.

Example 1

The carbonate formation pore pressure testing method provided by the invention comprises the following steps:

Step 1: Prepare different fracture-cavity carbonate rock models;

Step 2: Put different fracture-cavity carbonate rock models in the rock mechanics testing machine;

Step 3: Under the conditions of fixed temperature and confining pressure and changing pore pressure, use acoustic waves to test different fractured-cavity carbonate rock models, and obtain different pore pressures by the axis of each fracture-cavity carbonate rock model. The standard curve cluster composed of the relationship among the axial stress, shear wave and longitudinal wave;

Step 4: Obtain the measurement curve of the relationship between the axial stress, shear wave and longitudinal wave of the actual carbonate formation by using the acoustic logging data of the carbonate formation;

Step 5: Compare the measured curve with the standard curve cluster, and determine that the formation pore pressure of the fractured-cavity carbonate rock model corresponding to the curve closest to the measured curve in the standard curve cluster is the pore pressure of the actual carbonate rock formation .

The method for testing the pore pressure of carbonate formations provided by the present invention firstly prepares different models of fracture-cavity carbonate rocks; Experiment, drawing a standard curve cluster composed of the relationship between the axial stress, shear wave and longitudinal wave of each fractured-cavity carbonate rock model; The curves in the cluster are compared; finally, the actual formation pore pressure of carbonate rock is obtained. The method utilizes the test data of different fracture-cavity carbonate rock models and the acoustic logging data of the carbonate rock formation, and the actual formation pore pressure of the carbonate rock can be obtained from the chart.

Wherein, the relationship among axial stress, shear wave and longitudinal wave includes the relationship between axial stress and transverse wave, and/or the relationship between axial stress and longitudinal wave, and/or the relationship between transverse wave and longitudinal wave .

Among them, for the same pore pressure condition of the same fractured-vuggy carbonate rock model, the standard curve of the relationship among the axial stress, shear wave and longitudinal wave of the fractured-vuggy carbonate rock model can be drawn in the same chart. In this case, the relationship among axial stress, shear wave and longitudinal wave of the same fractured-cavity carbonate rock model under the same pore pressure condition can be shown in the same chart, and the results reflected in this chart are more abundant.

Among them, for the different pore pressure conditions of the same fractured-cavity carbonate rock model, the standard curve of the relationship between the axial stress, shear wave and longitudinal wave of the fracture-cavity carbonate rock model can be drawn in the same chart, and different pore Pressure conditions are distinguished by different legends. In this case, multiple curves appear in the graph. Among them, each legend corresponds to the relationship between the axial stress, shear wave and longitudinal wave of the fractured-cavity carbonate rock model under a certain pore pressure condition; combining the multiple curves, the same fracture-cavity The relationship between multiple curves of the carbonate rock model under different pore pressure conditions, thus, the relationship between pore pressure and axial stress, shear wave, and longitudinal wave can also be obtained, and the relationship between pore pressure and axial stress, shear wave , The impact of longitudinal waves.

Among them, for the same pore pressure condition of different fractured-vuggy carbonate rock models, the standard curve of the relationship between the axial stress, shear wave and longitudinal wave of the fractured-vuggy carbonate rock models can be drawn in the same chart, and different Cave carbonate models are distinguished by different legends. In this case, multiple curves appear in the graph. Among them, each legend corresponds to the relationship between the axial stress, shear wave, and longitudinal wave of a certain fractured-vuggy carbonate rock model under the pore pressure condition; The relationship between multiple curves of the salt rock model under the same pore pressure condition, thus, the relationship between the fracture-cavity carbonate rock model and axial stress, shear wave, longitudinal wave, and, the fracture-cavity Effects of carbonate rock models on axial stress, shear waves, and compressional waves.

Wherein, in the same graph, the axial stress can be represented by the abscissa, the transverse wave can be represented by the first ordinate, and the longitudinal wave can be represented by the second ordinate. In this case, the axial stress is the independent variable, the shear wave is the first dependent variable, and the longitudinal wave is the second dependent variable. In the case of the same legend, a curve can be used in the same graph to reflect the relationship between the axial stress and the shear wave. relationship, use another curve to reflect the relationship between the axial stress and the longitudinal wave. Thus, the relationship between the shear wave and the longitudinal wave can also be obtained when the axial stress is the same.

Wherein, the data of pore pressure, axial stress, shear wave, and longitudinal wave are collected by the data acquisition module; and/or, the standard curve cluster is drawn by the curve drawing module; and/or, the measurement curve is compared with the standard curve cluster The comparison is obtained by comparing the comparison modules; and/or, the formation pore pressure of the fractured-cavity carbonate model corresponding to the curve closest to the measured curve in the standard curve cluster is determined to be the pore pressure of the actual carbonate formation It is obtained through the judgment module. In this case, data acquisition, curve drawing, proximity comparison, and pore pressure determination are all automatically realized by computer, which not only has high work efficiency, but also eliminates errors in human operation and comparison.

Among them, the fractured-cavity carbonate rock model is the standard sample, the diameter of the standard sample is 50mm, and the height is 100mm. The sample of this size is a standard sample for rock mechanics testing machine, and the historical data is also richer, and more valuable test data can be obtained.

The fractured-cavity carbonate rock model used in the carbonate formation pore pressure testing method provided by Examples 2 to 22 of the present invention includes aggregate, hole simulation piece, and rock mass crack simulation piece; the quality of each component of the aggregate The ratio of parts is: cement: quartz sand: barite powder: water = (2~3): (1.5~2.5): (0.5~1): (0.4~1); the hole simulation parts are distributed in the aggregate; the rock Bulk crack simulations are also distributed in the aggregate. In this embodiment, 425 type Portland cement is used as cement. Wherein, the rock mass crack simulation piece can be sulfuric acid paper, or sketch paper. Among them, the characteristics of sulfuric acid paper are: high strength, good transparency, light resistance, high temperature resistance, high hardness, and it is not easy to deform when used as a simulation piece of fractured carbonate rock mass; The strength is slightly lower, and there are two specifications of thin and thick for selection. Wherein, the hole simulation part may be a spherical object, and in this embodiment, the spherical object is polystyrene particles with different particle diameters.

Embodiment 2-22

Example 23

Referring to accompanying drawing 1, the preparation method of the fracture-cavity carbonate rock model of application in the carbonate formation pore pressure test method that the embodiment of the present invention 23 provides comprises the following steps:

Step 1: Fill aggregates, hole simulation parts, and rock mass crack simulation parts into a mold according to the distribution law; in this embodiment, the model mold used in this embodiment is a cylindrical stainless steel mold. The stainless steel mold consists of 2 pieces of stainless steel plates firmly and tightly assembled together by bolts, 1 piece of steel plate forms the upper and lower bottom surfaces of the cylinder, and, 1 circumferential side, the upper side is vacated for adding the mixture, Form a cylindrical space with a diameter of 50mm and a height of 100mm.

Step 2: Stand for a predetermined time under predetermined temperature and humidity conditions, so that physical and chemical reactions between aggregates can fully occur;

Step 3: Remove the mold to obtain the fractured-cavity carbonate rock model.

Example 24

Referring to accompanying drawing 3, the preparation method of the fractured-cavity carbonate rock model that embodiment 24 of the present invention provides also includes the following steps:

Before the step 1 of filling aggregates, hole simulation parts and rock mass crack simulation parts in a mold according to the distribution law, step 10 is also included: the step of brushing lubricant on the inner wall of the mold. In this case, the separation between the mold and the porous carbonate pattern is easier when performing step 3, removal of the mold. In this embodiment, the lubricant is lubricating oil, in addition, other lubricants with lubricating effect and good brushing performance can also be selected.

Wherein, step 1 fills the aggregate, the hole simulation piece, and the rock mass crack simulation piece in a mold according to the distribution law, including the following steps:

Step 11: Prepare the aggregate and hole simulation piece, and fully stir the aggregate and hole simulation piece, so that the aggregate and hole simulation piece form a mixture;

Step 12: layering the mixture into the mold;

Step 13: Add the crack simulator between the layers of the mix.

Wherein, when step 12 is adding the mixture into the mold layer by layer, after adding the mixture of each layer, it also includes the step of compacting the added mixture.

Wherein, after the step of compacting the added mixture is completed, the step of roughening is also included, so as to ensure good adhesion between the layered prefabricated layers.

Wherein, the step of layering the mixture into the mold is realized by paving the mixture in the mold. In this case, when arranging the rock mass crack simulation piece, the rock mass crack simulation piece can be laid flat on the mixture layer, which can avoid too many folds or damage of the rock mass crack simulation piece.

Wherein, after the step 1 of filling aggregates, hole simulation parts and rock mass crack simulation parts in a mold according to the distribution law, step 14 is also included: scraping off the mixture beyond the opening surface of the model.

Wherein, after the step 14 of scraping off the mixture beyond the opening surface of the model is completed, the step 15 is also included.

Wherein, after the leveling step of step 15 is completed, the step of compacting in step 16 is also included, and after the step of compacting, the exposed mixture forms a flat surface.

The fractured-vuggy carbonate rock model provided by the invention can be used for testing the corresponding characteristics of the fractured-vuggy carbonate rock mass in terms of acoustics and mechanics.

The fractured-vuggy carbonate rock model prepared by the method provided by the present invention is based on the physical and mechanical characteristics of natural fractured-vuggy carbonate rocks, using industrial CT end-face scanning technology to describe its internal structure finely, and to identify cracks, pores, The size and distribution of structures such as holes, the mass ratio of each component of the aggregate is selected as follows: cement: quartz sand: barite powder: water = (2 ~ 3): (1.5 ~ 2.5): (0.5 ~ 1) : (0.4～1), and the aggregate is mixed with cavity simulation pieces and rock mass crack simulation pieces, which are not limited by the difficulty of natural carbonate rock collection, and can be simulated by adjusting pores and cracks as required A regular test block with a specific distribution of pores and cracks can be produced. When it is used in testing the acoustic and mechanical characteristics of fractured-vuggy carbonate rock mass, it avoids the test error caused by uneven stress during the loading process, thereby improving the accuracy of the analysis of test results.

Example 25

First of all, it is necessary to make a model mold and a compacting tool suitable for the present invention. The manufacturing method can be seen from the foregoing content, and will not be repeated here. And prepare sulfuric acid paper and polypropylene particle balls for simulation of fracture-cavity structure.

Considering the rock physical and mechanical properties of fractured-cavity carbonate rocks and the requirements of similarity theory in physical simulation tests, cement, quartz sand and barite powder were selected as aggregates, and the mass ratio was cement:quartz sand:barite powder : water=1.6:1.5:0.4:0.4. The production process is as follows:

(1) According to the production needs of the model size, weigh 32kg of 42.5 Portland cement, 30kg of quartz sand, and 8kg of barite powder in sequence, and put them into the batching box and mix evenly;

(2) Materials for simulating the pores of carbonate rock mass: polystyrene particles, two types of particles with a particle size less than 2mm and between 2mm and 5mm, the ratio of the two particle sizes is calculated as 2:1, and the prepared porosity is 8%. For the model sample, measure 8mL of polystyrene particles with a diameter of less than 2mm, measure 1250mL of polystyrene particles with a diameter of 2mm to 5mm, add them to the batching box and mix evenly;

(3) Take by weighing 0.08kg of pure water, pour it into the batching box, continue to stir evenly, and form a model raw material that can be used for laying;

(4) Take an appropriate amount of model mixture and pour it into a cylindrical stainless steel mold with a diameter of 50 mm and a height of 100 mm, and spread it evenly;

(5) tamping with self-made tamping tools;

(6) Cut the sulfuric acid paper according to the crack orientation and length set inside the set model sample, then use a utility knife to prefabricate the tamped sample, put the sulfuric acid paper, and then add a small amount of mixing material to Prefabricated cracks for filling;

(7) Then tamp, and use a utility knife to lightly scrape the tamped surface for planing;

(8) Continue to use the methods of adding, paving, prefabricating cracks, adding sulfuric acid paper, adding materials, compacting and planing to make subsequent layers until the model raw material exceeds the upper surface of the mould;

(9) Scrape off the raw materials that exceed the upper surface of the mold, and level them so that the upper surface forms a plane;

(10) Place the mold with the model material of the prefabricated slit hole in an environment with a constant temperature of 25°C and a relative humidity of 90% for curing. After 24 hours, remove the mold to obtain a molded mold with a diameter of 50 mm and a height of 100 mm. The cylinder model sample can be seen in Figure 2. Keep the same temperature and humidity conditions, and after curing for 28 days, it is used for temperature and confining pressure fixed, and acoustic wave response characteristics test under different pore fracturing.

Embodiment 25 of the present invention provides a method for making indoor simulated carbonate rock pores, fracture-cavity rock mass acoustic and mechanical testing test geological body models, by selecting raw materials similar to the physical and mechanical properties of natural carbonate rocks to simulate Carbonate rocks are manufactured with fractures of predetermined orientation and length and a certain porosity model, which is not limited by the difficulty of grasping the internal structure of natural carbonate rocks. Different fracture distributions and different porosity can be obtained by making model molds according to needs. The cube test block avoids the differences in the internal structure of each sample of natural carbonate rock, thereby improving the accuracy of the analysis of the final test results. Example 25 of the present invention can analyze the response characteristics of different factors to the joint action of acoustics and mechanics by changing the particle size and content of polypropylene particles in the material, as well as the number, orientation and length of simulated cracks, avoiding the natural experiment. The interference to the test results caused by the discreteness of the physical and mechanical properties of samples is beneficial to the comparison and analysis of the test results and provides the practicability of the present invention. The invention has clear steps, is simple and easy to implement, not only reduces the test cost, but also improves the test efficiency, and at the same time ensures the accuracy of the test data.

Example 26

The carbonate formation pore pressure testing device provided in Embodiment 26 of the present invention includes a rock mechanics testing machine, a data acquisition module, a curve drawing module, a comparison module, and a judgment module,

The rock mechanics testing machine is used to load different fracture-cavity carbonate rock models, and provides test conditions for temperature, confining pressure fixed, and pore pressure change;

The data acquisition module is used to obtain the axial stress, shear wave, and longitudinal wave test data of each fractured-cavity carbonate rock model at different pore pressures; and, acoustic logging data of carbonate rock formations;

The curve drawing module is used to draw the standard curve cluster composed of the relationship between the axial stress, shear wave and longitudinal wave of each fracture-cavity carbonate rock model at different pore pressures; and, the axis of the actual carbonate rock formation The measurement curve of the relationship between axial stress, shear wave and longitudinal wave;

The comparison module is used to compare the measurement curve with the standard curve cluster, and obtain the closeness between the measurement curve and each curve in the standard curve cluster;

According to the proximity, the judging module determines that the formation pore pressure of the fractured-cavity carbonate model corresponding to the curve closest to the measurement curve in the standard curve cluster is the pore pressure of the actual carbonate formation.

In this embodiment, the rock mechanics testing machine is the MTS815.03 pressure testing system produced by MTS Company of the United States, which is mainly used for conventional mechanical tests of electro-hydraulic servo control of materials such as rocks and concrete. Shaft pressurization and measurement system.

The carbonate rock formation pore pressure testing device provided in Embodiment 26 of the present invention is based on the carbonate rock formation pore pressure testing method provided in any one of Embodiments 1 to 25 of the present invention. Data collection, curve drawing, proximity The comparison and determination of pore pressure are all automatically realized by computer, which not only has high work efficiency, but also eliminates the errors of human operation and comparison.

Among them, the closeness includes numerical closeness, and trend closeness. Through these two dimensions, the closest carbonate formation pore pressure can be guaranteed to be selected. This ensures the accuracy of the test results.

While preferred embodiments of the invention have been described, additional changes and modifications to these embodiments can be made by those skilled in the art once the basic inventive concept is appreciated. Therefore, it is intended that the appended claims be construed to cover the preferred embodiment as well as all changes and modifications which fall within the scope of the invention.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (10)

1. a For Pore Pressure on Carbonate Rock Formation method of testing, is characterized in that, comprises the following steps:

Prepare different seam hole acid carbonate rock models;

Described different seam hole acid carbonate rock model is placed in rock mechanics experiment machine respectively;

Fix in temperature, confined pressure, under the condition of pore pressure change, utilize seam hole acid carbonate rock models different described in sonic test, when obtaining different aperture pressure, the calibration curve bunch be made up of the relation between the axial stress of each described seam hole acid carbonate rock model, shear wave, compressional wave;

Utilize carbonate formation sound wave measuring well curve, obtain the experiment curv of the relation between the axial stress of actual carbonate formation, shear wave, compressional wave;

Described experiment curv and described calibration curve bunch are compared, assert that the formation pore pressure of seam hole acid carbonate rock model corresponding with the immediate curve of described experiment curv in described calibration curve bunch is the pore pressure of described actual carbonate formation.

2. For Pore Pressure on Carbonate Rock Formation method of testing according to claim 1, it is characterized in that, relation between described axial stress, shear wave, compressional wave comprises, relation between axial stress and shear wave, and/or, relation between axial stress and compressional wave, and/or, the relation between shear wave and compressional wave.

3. For Pore Pressure on Carbonate Rock Formation method of testing according to claim 2, it is characterized in that, for the same pore pressure condition of same seam hole acid carbonate rock model, the Specification Curve of Increasing of the relation between the axial stress of described seam hole acid carbonate rock model, shear wave, compressional wave is in same chart.

4. For Pore Pressure on Carbonate Rock Formation method of testing according to claim 2, it is characterized in that, for the different aperture pressure condition of same seam hole acid carbonate rock model, the Specification Curve of Increasing of the relation between the axial stress of described seam hole acid carbonate rock model, shear wave, compressional wave is in same chart, and the different legend of described different aperture pressure condition is distinguished.

5. For Pore Pressure on Carbonate Rock Formation method of testing according to claim 2, it is characterized in that, for the same pore pressure condition of difference seam hole acid carbonate rock model, the Specification Curve of Increasing of the relation between the axial stress of described seam hole acid carbonate rock model, shear wave, compressional wave is in same chart, and the different legend of described difference seam hole acid carbonate rock model is distinguished.

6., according to described For Pore Pressure on Carbonate Rock Formation method of testing arbitrary in claim 3 ~ 5, it is characterized in that, in described same icon, described axial stress is abscissa, and described shear wave is the first ordinate, and described compressional wave is the second ordinate.

7. For Pore Pressure on Carbonate Rock Formation method of testing according to claim 1, is characterized in that, described pore pressure, axial stress, shear wave, P wave data are obtained by data collecting module collected; And/or described calibration curve bunch is drawn by Drawing of Curve module and is obtained; And/or described experiment curv and described calibration curve bunch being compared to be compared by comparison module is obtained; And/or, assert that the formation pore pressure of seam hole acid carbonate rock model corresponding with the immediate curve of described experiment curv in described calibration curve bunch is that the pore pressure of described actual carbonate formation is obtained by judge module.

8. For Pore Pressure on Carbonate Rock Formation method of testing according to claim 1, is characterized in that, seam hole acid carbonate rock model is standard specimen, and the diameter of described standard specimen is 50mm, is highly 100mm;

As preferably, described seam hole acid carbonate rock model comprises aggregate, hole simulating piece, Rockmass fractures simulating piece;

The ratio of quality and the number of copies of each component of described aggregate is, cement: quartz sand: blanc fixe: water=(2 ~ 3): (1.5 ~ 2.5): (0.5 ~ 1): (0.4 ~ 1);

Described hole simulating piece is distributed in described aggregate;

Described Rockmass fractures simulating piece is also distributed in described aggregate;

As preferably, described Rockmass fractures simulating piece is template, or, sketching paper;

As preferably, described hole simulating piece is sphere;

As preferably, described sphere is the different granules of polystyrene of particle diameter.

9. For Pore Pressure on Carbonate Rock Formation method of testing according to claim 8, is characterized in that, the preparation method of described seam hole acid carbonate rock model comprises the following steps:

Described aggregate, hole simulating piece, Rockmass fractures simulating piece are filled in a mould according to the regularity of distribution;

Under predetermined temperature and humidity condition, leave standstill the scheduled time, make fully physical reactions and chemical reaction to occur between described aggregate;

Remove described mould, obtain described seam hole acid carbonate rock model;

As preferably, before described aggregate, hole simulating piece, Rockmass fractures simulating piece are filled in the step in a mould according to the regularity of distribution, be also included in the step of brushing sliding agent on described mould inner wall;

As preferably, described aggregate, hole simulating piece, Rockmass fractures simulating piece are filled in a mould according to the regularity of distribution and comprise the following steps:

Prepare described aggregate and hole simulating piece, and fully stir described aggregate and hole simulating piece, make described aggregate and hole simulating piece form mixture;

Described mixture layering is joined in described mould;

Described results of fracture simulation part is joined described mixture between layers;

As preferably, when described mixture layering being joined in described mould, after every layer of described mixture has added, also comprise the step that the described mixture added is tamped;

As preferably, after the step tamped the described mixture added completes, also comprise the step of hacking;

As preferably, be that the mode by being paved in the mold by described mixture realizes by the described mixture layering step joined in described mould;

As preferably, after described aggregate, hole simulating piece, Rockmass fractures simulating piece are filled in the step in a mould according to the regularity of distribution, also comprise the step struck off by the mixture exceeding described model opening surface;

As preferably, after the step that the mixture exceeding described model opening surface strikes off being completed, also comprise smooth step;

As preferably, after described smooth step completes, also comprise the step of compacting, after the step of described compacting, be exposed to outer described mixture and form a burnishing surface.

10. a For Pore Pressure on Carbonate Rock Formation testing arrangement, is characterized in that, comprises rock mechanics experiment machine, data acquisition module, Drawing of Curve module, comparison module, judge module,

Described rock mechanics experiment machine, for loading different seam hole acid carbonate rock models, provides temperature, confined pressure fixes, the test conditions of pore pressure change;

When described data acquisition module is for obtaining different aperture pressure, axial stress, shear wave, the compressional wave experimental data of each described seam hole acid carbonate rock model; With, carbonate formation sound wave measuring well curve;

When described Drawing of Curve module is for drawing different aperture pressure, the calibration curve bunch be made up of the relation between the axial stress of each described seam hole acid carbonate rock model, shear wave, compressional wave; With the experiment curv of the relation between the axial stress of, actual carbonate formation, shear wave, compressional wave;

Described comparison module is used for described experiment curv and described calibration curve bunch to compare, and the degree of approach of each curve in obtaining described experiment curv and described calibration curve bunch;

Described judge module, according to the described degree of approach, assert that the formation pore pressure of seam hole acid carbonate rock model corresponding with the immediate curve of described experiment curv in described calibration curve bunch is the pore pressure of described actual carbonate formation;

As preferably, it is close that the described degree of approach comprises numerical value, and tendency is close.