Stratum interface short source distance remote detection device, system and method

Abstract

The invention belongs to the field of petroleum engineering technology, and provides a formation interface short-distance and long-distance detection device, system and method in order to solve the problem of contradiction between detection depth and distance, the formation interface short-distance and long-distance detection device comprises a transmitting end and a receiving end, the transmitting end comprises a transmitting coil, and the receiving end comprises a receiving coil; the transmitting coil and the receiving coil are arranged on the drill rod at intervals; the transmitting coil and / or the receiving coil are / is a closed coil which is partially or completely shielded by a metal shielding layer; the system further comprises a signal processing device and a boundary generating device. The transmitting end transmits a magnetic field signal or an electric field signal to the stratum through the transmitting coil, the receiving end receives the electric field signal or the magnetic field signal returned from the stratum through the receiving coil, and a magnetic-electric mixed signal receiving and transmitting mode or a pure electric field signal receiving and transmitting mode is formed. Compared with a traditional method for transmitting and receiving signals by adopting an unshielded coil or an open coil, the method is simple and convenient in measurement, stable in measured signal and high in noise resistance.

Description

Technical Field

[0001] The present invention belongs to petroleum engineering technology, and in particular relates to a short-source long-distance detection device, system and method for formation interface. Background Art

[0002] Geosteering while drilling is an important means of oil and gas reservoir exploration and development. This technology is crucial to achieve accurate targeting of the target layer, avoid drilling risks in real time, and maximize the oil and gas production capacity of horizontal wells. Among them, the key to geosteering while drilling is whether it can achieve forward logging and timely discover formation interfaces or abnormal bodies. In the process of realizing the present invention, the inventors found that the electromagnetic wave forward logging instrument involved in the prior art usually has a detection range of tens of meters by means of multi-component magnetic field signal combination and modular structure design. However, the prior art also has the following problems: (1) The source distance between the transmitting and receiving antennas of the forward logging instrument is too long, which makes it difficult to synchronize the signals between different short sections; (2) The scattering signal of the measured magnetic field caused by the formation interface in front is weak and the signal-to-noise ratio is low; (3) In terms of data processing, there is too much prior information that depends on the inversion of the formation parameters in front of the drill bit, and high requirements are placed on field applications.

[0003] At present, forward-looking long-range detection is mainly based on tilted or orthogonally closed transmitting and receiving antennas. Its essence is to measure the magnetic field component excited by the magnetic dipole source. The long-range detection instruments designed based on this forward-looking long-range detection principle have many problems such as weak measurement signals, long source distances, and poor azimuth sensitivity. In addition, some long-range detection instruments use semicircular antennas (open-loop semi-coil) as transmitting antennas. The response information corresponding to this method is easily affected by the environment, and the measurement effect is poor. At the same time, the measurement results obtained using the semicircular antenna involve magnetic field information, which must rely on the rotation of the instrument to be extracted.

[0004] Therefore, how to use a shorter instrument size (≦5m) to achieve long-distance detection of geological anomalies in front of the drill bit (≧15m) is an inevitable requirement for the development of logging while drilling and a key issue that needs to be solved urgently. At the same time, solving this problem is of great significance to broadening the horizon of geosteering. Summary of the invention

[0005] The invention provides a stratum interface short source distance long detection device, which solves the contradiction between detection depth and source distance by receiving or transmitting electric field signals.

[0006] The present invention is achieved through the following technical solutions:

[0007] A short-source long-distance detection device for a stratum interface comprises a transmitting end and a receiving end, wherein the transmitting end comprises a transmitting coil and the receiving end comprises a receiving coil; the transmitting coil and the receiving coil are arranged on a drill pipe at intervals; the transmitting coil and / or the receiving coil are closed coils partially or completely shielded by a metal shielding layer.

[0008] Furthermore, the transmitting coil and the receiving coil are parallel to each other.

[0009] Furthermore, the included angle between the transmitting coil and the axis of the drill rod is 0 to 90°; the included angle between the receiving coil and the axis of the drill rod is 0 to 90°.

[0010] Furthermore, the range of partial shielding by the metal shielding layer is 1 / 4 to 1 / 2 of the circumference of the closed coil.

[0011] Furthermore, the metal shielding layer is a metal shielding cover.

[0012] Furthermore, the transmitting end includes an exciter, and the exciter is used to provide alternating current to the transmitting coil.

[0013] Furthermore, there are a plurality of transmitting ends and receiving ends, and the transmitting coils of the transmitting ends and the receiving coils of the receiving ends are arranged crosswise along the axis direction of the drill pipe.

[0014] Furthermore, the receiving end also includes an electromagnetic sensor; the electromagnetic sensors are evenly distributed on the receiving coil in a circumferential direction; one end of the electromagnetic sensor is fixedly connected to the drill pipe, and the other end passes through the receiving coil and is electrically connected to the measuring electrode.

[0015] Furthermore, the receiving end also includes a protective cover made of non-metallic material; the receiving coil and the electromagnetic sensor are located inside the protective cover, and the measuring electrode is located on the outer surface of the protective cover.

[0016] Furthermore, the protective cover is made of glass fiber reinforced plastic material.

[0017] The present invention also provides a short-source long-range detection system for a formation interface, comprising the short-source long-range detection device for the formation interface described in the present invention, and also comprising a signal processing device and a boundary generating device; the signal processing device is used to generate formation interface boundary information in real time according to the signal collected by the receiving end; the boundary generating device is used to generate the complete boundary distribution characteristics of the front formation interface according to the formation interface boundary information generated in real time.

[0018] The present invention also provides a short-source long-range detection method for a stratum interface, which adopts the short-source long-range detection system for a stratum interface of the present invention and includes the following steps: a transmitting end transmits a magnetic field signal or an electric field signal to the stratum through a transmitting coil, and a receiving end receives the electric field signal or the magnetic field signal returned from the stratum through a receiving coil, thereby forming a magnetic-electric mixed signal transmission and reception mode or a pure electric field signal transmission and reception mode.

[0019] Compared with the prior art, the beneficial effects of the present invention include:

[0020] 1. The metal shielding layer is used to shield the magnetic field signal of the coil, and the electric field signal takes the advantage, so that the coil presents electric field characteristics to the outside, realizes the reception or transmission of electric field signals, and utilizes the characteristics of high electric field signal intensity, slow attenuation and high signal-to-noise ratio to achieve the purpose of short source distance and long distance detection: the detection depth can be greater than or equal to 15m under the condition that the source distance is less than or equal to 5m.

[0021] 2. Compared with the traditional method of using non-shielded coils or open coils for signal transmission and reception, the present invention has simple measurement, stable measurement signals and strong noise resistance.

[0022] 3. When the present invention adopts a pure electric field signal receiving and transmitting method, it can also realize remote detection of the formation interface under non-rotating conditions, thereby effectively improving the formation description accuracy in front of and in front of the downhole drilling tool, and improving the efficiency of oil and gas exploration and development. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the overall structure;

[0024] Figure 2 A schematic diagram of the structure of the detection device;

[0025] Figure 3 It is a cross-sectional diagram of the transmitting end and the receiving end;

[0026] Figure 4 Schematic diagram of the potential distribution of the shielding coil. DETAILED DESCRIPTION

[0027] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0028] Compared with the prior art, the present invention solves the contradiction between the detection depth and source distance of the prior art instruments, and can realize the detection of formation interfaces at a longer distance under the condition of a shorter source distance. The present invention mainly adopts a magnetic coil method with a partially closed shielding portion to realize the detection of pseudo-electric field information, thereby realizing the detection of formation interfaces at a short source distance and a long distance.

[0029] like Figure 1As shown, a short-source long-range detection system for a formation interface includes a short-source long-range detection device for a formation interface, a signal processing device and a boundary generating device; the signal processing device is used to generate formation interface boundary information in real time according to the signal collected by the receiving end; the boundary generating device is used to generate the complete boundary distribution characteristics of the front formation interface according to the formation interface boundary information generated in real time.

[0030] A short-source long-distance detection device for a stratum interface comprises a transmitting end and a receiving end, wherein the transmitting end comprises a transmitting coil and the receiving end comprises a receiving coil; the transmitting coil and the receiving coil are arranged on a drill pipe at intervals; the transmitting coil and / or the receiving coil are closed coils partially or completely shielded by a metal shielding layer.

[0031] Preferably, the transmitting coil and the receiving coil are parallel to each other.

[0032] Preferably, the angle between the transmitting coil and the axis of the drill rod is 0 to 90°; the angle between the receiving coil and the axis of the drill rod is 0 to 90°.

[0033] Preferably, the range of partial shielding by the metal shielding layer is 1 / 4 to 1 / 2 of the circumference of the closed coil.

[0034] Preferably, the metal shielding layer is a metal shielding cover.

[0035] Preferably, the transmitting end includes an exciter, and the exciter is used to provide alternating current to the transmitting coil.

[0036] Preferably, there are a plurality of transmitting ends and receiving ends, and the transmitting coil of the transmitting end and the receiving coil of the receiving end are arranged crosswise along the axis direction of the drill pipe. Figure 2 As shown, a source distance array with four source distances (0.4m, 0.6m, 0.8m and 1.8m) and a multi-transmitting and multi-receiving antenna combination with three operating frequencies (100kHz, 500kHz and 2MHz) enables the stratum interface long-distance detection system to have a wider detection range in the current stratum, and the detection range can fully cover all stratum interface boundaries in the current stratum.

[0037] According to the design goal, a group of transmitting coils is constructed. The transmitting coil can be composed of one or more than two coils. The transmitting coil can be set on one side of the receiving coil or on both sides of the receiving coil.

[0038] According to the design goal, a set of receiving coils is constructed, and the receiving coils can be one or more than two.

[0039] Preferably, the receiving end further includes an electromagnetic sensor; the electromagnetic sensors are evenly distributed on the receiving coil in a circumferential direction; one end of the electromagnetic sensor is fixedly connected to the drill pipe, and the other end passes through the receiving coil and is electrically connected to the measuring electrode.

[0040] The receiving coil is used to measure the first potential of the longitudinal position of the receiving end, that is, the potential Vh of the receiving coil. The measuring electrode is used to measure the potential strength information in space, and the electromagnetic sensor converts the potential strength information to generate corresponding potential parameters, thereby obtaining the second potentials in multiple circumferential directions.

[0041] Preferably, the receiving end further comprises a protective cover made of non-metallic material; the receiving coil and the electromagnetic sensor are located inside the protective cover, and the measuring electrode is located on the outer surface of the protective cover.

[0042] Preferably, the protective cover is made of glass fiber reinforced plastic material.

[0043] A short-source long-range detection method for a stratum interface adopts a stratum interface short-source long-range detection system and comprises the following steps: a transmitting end transmits a magnetic field signal or an electric field signal to a stratum through a transmitting coil, and a receiving end receives the electric field signal or the magnetic field signal returned from the stratum through a receiving coil, thereby forming a magnetic-electric mixed signal transmission and reception mode or a pure electric field signal transmission and reception mode.

[0044] The signal processing device converts the signal collected by the receiving end into the electric potential information of the stratum interface, and generates the boundary information of the stratum interface according to the electric potential information of the stratum interface.

[0045] Preferably, the signal processing device is further used to respectively calculate the potential difference between two pairs of electromagnetic sensors having a symmetrical position relationship, and obtain an intermediate potential used to represent the potential of the receiving end using the following expression, so as to generate the formation interface boundary information according to the intermediate potential combined with the first potential:

[0046] Ve=sqrt(△V1 2 +△V2 2 )

[0047] Among them, Ve represents the intermediate potential, △V1 and △V2 represent two sets of potential differences respectively, and sqrt represents the square root sign.

[0048] Preferably, the signal processing device is further used to combine the first potential and the intermediate potential using the following expression to obtain the amplitude change relationship characteristics between the two, and then obtain the formation interface boundary information according to the amplitude change relationship characteristics:

[0049] Att=abs(Ve / Vh)

[0050] Here, Att represents the amplitude ratio, Vh represents the first potential, and abs represents the absolute value sign.

[0051] Example 1

[0052] In this embodiment, the transmitting coil of the formation interface short-source long-range detection device is a closed coil partially shielded by a metal shielding layer, and the shielding range is 1 / 2 of the circumference of the closed coil. Its receiving coil is a closed coil partially shielded by a metal shielding layer, and the shielding range is 1 / 2 of the circumference of the closed coil.

[0053] The transmitting coil and the receiving coil are parallel to each other, and the angle between the receiving coil and the axis of the drill pipe is 45°.

[0054] The metal shielding layer is a metal shielding cover covering the shielding range.

[0055] The transmitting end includes an exciter, which is used to provide alternating current with a frequency of 50 kHz to the transmitting coil.

[0056] A short-source long-range detection system for a formation interface comprises the short-source long-range detection device for the formation interface of this embodiment, and also comprises a signal processing device and a boundary generating device; the signal processing device is used to generate formation interface boundary information in real time according to the signal collected by the receiving end; the boundary generating device is used to generate the complete boundary distribution characteristics of the front formation interface according to the formation interface boundary information generated in real time.

[0057] A method for short-source long-range detection of stratum interfaces adopts the short-source long-range detection system of the stratum interface of this embodiment and includes the following steps: a transmitting end transmits an electric field signal to the stratum through a transmitting coil, and a receiving end receives the electric field signal returned from the stratum through a receiving coil, thereby forming a pure electric field signal transmission and reception mode.

[0058] The exciter provides alternating current to the transmitting coil, causing the transmitting coil to induce a magnetic field. Since the transmitting coil is partially shielded, the magnetic field signal is intercepted in the metal shielding layer, and then the metal shielding layer induces an electric field, causing the transmitting coil to transmit an electric field signal to the formation. The formation forms an electric field. The formation interface in the formation has high conductivity compared to the non-formation interface, so it can transmit the electric field signal to the receiving coil. Similarly, due to the existence of the metal shielding layer, the metal shielding layer induces an electric field in the receiving coil, and the entire receiving coil presents a pseudo-electric field characteristic to the outside.

[0059] The signal processing device converts the electrical signal collected by the receiving device into the electric potential information of the formation interface, and generates the boundary information of the formation interface according to the electric potential information of the formation interface.

[0060] In circuit implementation, the potential information is obtained by measuring the voltage. There are different measurement methods. One is to determine a zero voltage position, a ground position, and the other is to use a differential circuit to obtain the voltage.

[0061] Example 2

[0062] In this embodiment, the transmitting coil of the formation interface short-source long-range detection device is a closed coil partially shielded by a metal shielding layer, and the shielding range is 1 / 4 of the circumference of the closed coil. Its receiving coil is a closed coil partially shielded by a metal shielding layer, and the shielding range is 1 / 4 of the circumference of the closed coil.

[0063] The transmitting coil and the receiving coil are parallel to each other, and the angle between the receiving coil and the axis of the drill pipe is 60°.

[0064] The metal shielding layer is a wire mesh that wraps around the shielding area on the closed coil.

[0065] The transmitting end includes an exciter, which is used to provide alternating current with a frequency of 2 MHz to the transmitting coil.

[0066] The exciter provides alternating current to the transmitting coil, causing the transmitting coil to induce a magnetic field. Since the transmitting coil is partially shielded, the magnetic field signal is intercepted in the metal shielding layer, and then the metal shielding layer induces an electric field, causing the transmitting coil to transmit an electric field signal to the formation. The formation forms an electric field. The formation interface in the formation has high conductivity compared to the non-formation interface, so it can transmit the electric field signal to the receiving coil. Similarly, due to the existence of the metal shielding layer, the metal shielding layer induces an electric field in the receiving coil, and the entire receiving coil presents a pseudo-electric field characteristic to the outside.

[0067] The signal processing device converts the electrical signal collected by the receiving device into the electric potential information of the formation interface, and generates the boundary information of the formation interface according to the electric potential information of the formation interface.

[0068] In circuit implementation, the potential information is obtained by measuring the voltage. There are different measurement methods. One is to determine a zero voltage position, a ground position, and the other is to use a differential circuit to obtain the voltage.

[0069] Example 3

[0070] In this embodiment, the transmitting coil of the formation interface short-source long-range detection device is a closed coil completely shielded by a metal shielding layer, that is, the shielding range is the circumference of the closed coil, and its receiving coil is a closed coil completely shielded by a metal shielding layer, that is, the shielding range is the circumference of the closed coil.

[0071] The included angle between the transmitting coil and the axis of the drill pipe is 90°, and the included angle between the receiving coil and the axis of the drill pipe is 0°.

[0072] The metal shielding layer is a metal foil, such as tin foil or aluminum foil, that wraps the shielding area on the closed coil.

[0073] The transmitting end includes an exciter, and the exciter is used to provide alternating current to the transmitting coil.

[0074] The transmitting end includes an exciter, which is used to provide alternating current with a frequency of 1 MHz to the transmitting coil.

[0075] The exciter provides alternating current to the transmitting coil, causing the transmitting coil to induce a magnetic field. Since the transmitting coil is partially shielded, the magnetic field signal is intercepted in the metal shielding layer, and then the metal shielding layer induces an electric field, causing the transmitting coil to transmit an electric field signal to the formation. The formation forms an electric field. The formation interface in the formation has high conductivity compared to the non-formation interface, so it can transmit the electric field signal to the receiving coil. Similarly, due to the existence of the metal shielding layer, the metal shielding layer induces an electric field in the receiving coil, and the entire receiving coil presents a pseudo-electric field characteristic to the outside.

[0076] Example 4

[0077] In this embodiment, the transmitting coil of the formation interface short-source long-range detection device is a closed coil partially shielded by a metal shielding layer, and the shielding range is 1 / 3 of the circumference of the closed coil. Its receiving coil is a closed coil (no metal shielding layer is set).

[0078] The included angle between the transmitting coil and the axis of the drill pipe is 60°, and the included angle between the receiving coil and the axis of the drill pipe is 30°.

[0079] The metal shielding layer is a metal foil, such as tin foil, that wraps around the shielding area on the closed coil.

[0080] The transmitting end includes an exciter, which is used to provide alternating current with a frequency of 800 kHz to the transmitting coil.

[0081] The exciter provides alternating current to the transmitting coil, causing the transmitting coil to induce a magnetic field. Since the transmitting coil is partially shielded, the magnetic field signal is intercepted in the metal shielding layer, and then the metal shielding layer induces an electric field, causing the transmitting coil to transmit an electric field signal to the formation. The formation forms an electric field. The formation interface in the formation has high conductivity compared with the non-formation interface, so it can transmit the electric field signal to the receiving coil. The receiving coil simultaneously induces electric field signals and magnetic field signals through electromagnetic induction. Compared with the receiving coil with a metal shielding layer, the induced electric field signal is weakened, but since the formation directly transmits the electric field signal, the signal attenuation is less, and the receiving coil can still be guaranteed to have a higher electric field signal.

[0082] The signal processing device converts the electrical signal collected by the receiving device into the electric potential information of the formation interface, and generates the boundary information of the formation interface according to the electric potential information of the formation interface.

[0083] In circuit implementation, the potential information is obtained by measuring the voltage. There are different measurement methods. One is to determine a zero voltage position, a ground position, and the other is to use a differential circuit to obtain the voltage.

[0084] Example 5

[0085] refer to Figure 3 As shown, in this embodiment, the transmitting coil 2 of the stratum interface short-source long-range detection device is a closed coil (without a metal shielding layer), and its receiving coil 3 is a closed coil partially shielded by a metal shielding layer 4, and the shielding range is 1 / 2 of the circumference of the closed coil.

[0086] The transmitting coil and the receiving coil are parallel to each other, and the angle between the receiving coil and the axis of the drill rod 1 is 90°.

[0087] The metal shielding layer is a metal foil, such as tin foil or aluminum foil, that wraps the shielding area on the closed coil.

[0088] The receiving end further comprises a protective cover 5 made of non-metallic material; the receiving coil 3 is located inside the protective cover 5; and the protective cover 5 is made of glass fiber reinforced plastic material.

[0089] The transmitting end includes an exciter, which is used to provide alternating current with a frequency of 500 kHz to the transmitting coil.

[0090] The exciter provides alternating current to the transmitting coil, causing the transmitting coil to induce a magnetic field and transmit electromagnetic signals to the formation in the form of electromagnetic waves. The formation interface in the formation has high conductivity compared to the non-formation interface, so it can transmit the electromagnetic signal to the receiving coil. Since the receiving coil is partially shielded, the magnetic field signal is intercepted in the metal shielding layer, and then the metal shielding layer induces an electric field, and the receiving coil as a whole exhibits electric field characteristics.

[0091] The signal processing device converts the electrical signal collected by the receiving device into the electric potential information of the formation interface, and generates the boundary information of the formation interface according to the electric potential information of the formation interface.

[0092] In circuit implementation, the potential information is obtained by measuring the voltage. There are different measurement methods. One is to determine a zero voltage position, a ground position, and the other is to use a differential circuit to obtain the voltage.

[0093] Although the embodiments disclosed in the present invention are as above, the contents described are only embodiments adopted for facilitating the understanding of the present invention and are not intended to limit the present invention. Any technician in the technical field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

[0094] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0095] In the description of the present invention, unless otherwise specified, the terms "upper", "lower", "left", "right", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0096] The above technical scheme is only a specific implementation method of the present invention. For those skilled in the art, it is easy to make various types of improvements or modifications based on the principles disclosed in the present invention, and it is not limited to the technical scheme described in the above specific embodiments of the present invention. Therefore, the above description is only preferred and does not have a restrictive meaning.

Claims

1. A short-source long-distance detection device for stratum interface, characterized in that: It comprises a transmitting end and a receiving end, wherein the transmitting end comprises a transmitting coil, and the receiving end comprises a receiving coil; the transmitting coil and the receiving coil are arranged on the drill rod at intervals; the transmitting coil and / or the receiving coil are closed coils partially or completely shielded by a metal shielding layer.

2. The stratum interface short-source long-distance detection device according to claim 1, characterized in that: The transmitting coil and the receiving coil are parallel to each other.

3. The stratum interface short-source long-distance detection device according to claim 1 or 2, characterized in that: The included angle between the transmitting coil and the axis of the drill pipe is 0 to 90°; the included angle between the receiving coil and the axis of the drill pipe is 0 to 90°.

4. The stratum interface short-source long-distance detection device according to claim 1, characterized in that: The range of partial shielding by the metal shielding layer is 1 / 4 to 1 / 2 of the circumference of the closed coil.

5. The stratum interface short-source long-distance detection device according to claim 1, characterized in that: The metal shielding layer is a metal shielding cover.

6. The short-source long-distance detection device for stratum interface according to claim 1, characterized in that: The transmitting end includes an exciter, and the exciter is used to provide alternating current to the transmitting coil.

7. The short-source long-distance detection device for stratum interface according to claim 1 is characterized in that: There are a plurality of transmitting ends and receiving ends, and the transmitting coils of the transmitting ends and the receiving coils of the receiving ends are arranged crosswise along the axis direction of the drill rod.

8. The short-source long-distance detection device for stratum interface according to claim 1 is characterized in that: The receiving end also includes an electromagnetic sensor; the electromagnetic sensors are evenly distributed on the receiving coil in a circumferential direction; one end of the electromagnetic sensor is fixedly connected to the drill pipe, and the other end passes through the receiving coil and is electrically connected to the measuring electrode.

9. The short-source long-distance detection device for stratum interface according to claim 8, characterized in that: The receiving end also includes a protective cover made of non-metallic material; the receiving coil and the electromagnetic sensor are located inside the protective cover, and the measuring electrode is located on the outer surface of the protective cover.

10. The short-source long-distance detection device for stratum interface according to claim 9, characterized in that: The protective cover is made of glass fiber reinforced plastic material.

11. A short-source long-range detection system for stratum interface, characterized in that: It comprises a short-source long-range detection device for formation interfaces as described in any one of claims 1 to 10, and also comprises a signal processing device and a boundary generating device; the signal processing device is used to generate formation interface boundary information in real time according to the signal collected by the receiving end; the boundary generating device is used to generate the complete boundary distribution characteristics of the front formation interface according to the formation interface boundary information generated in real time.

12. A method for detecting stratum interface with short source and long distance, characterized in that: The short-source long-range detection system for the formation interface as described in claim 11 is used, and includes the following steps: the transmitting end transmits a magnetic field signal or an electric field signal to the formation through a transmitting coil, and the receiving end receives the electric field signal or the magnetic field signal returned from the formation through a receiving coil, thereby forming a magnetic-electric mixed signal transmission and reception mode or a pure electric field signal transmission and reception mode.

13. The method for detecting stratum interface with short source and long distance according to claim 12, characterized in that: The signal processing device converts the signal collected by the receiving device into the electric potential information of the formation interface, and generates the boundary information of the formation interface according to the electric potential information of the formation interface.

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