US20120176863A1 - Portable device and method to generate seismic waves - Google Patents

Abstract

A portable seismic source for generating a seismic wave in the ground. The portable seismic source includes a casing containing an impulsive energy device; a base plate configured to be placed on the ground; and a stabilizing foot mechanism configured to be provided between the casing and the base plate. The stabilizing foot mechanism includes a stabilizer which is fixed relative to the casing and configured to be placed on the base plate and a stanchion that is configured to move relative to the stabilizer and to enter through the stabilizer and apply a force on the base plate when energy is applied from the impulsive energy device.

Description

CROSS REFERENCE TO RELATED APPLICATIONS
• The present application is related to and claims the benefit of priority of U.S. Provisional Application 61/431,963, having the title “Portable Device and Method to Generate Seismic Waves,” and being authored by J. Jurok et al., the entire content of which is incorporated herein by reference.
BACKGROUND
• 1. Technical Field
• Embodiments of the subject matter disclosed herein generally relate to methods and systems and, more particularly, to mechanisms and techniques for generating seismic waves.
• 2. Discussion of the Background
• During the past years, the interest in developing new oil and gas production fields has dramatically increased. Thus, the industry has now extended drilling to locations that are environmentally sensitive or with limited vehicular access (e.g., riparian areas), which appear to overlay oil and gas reserves. Traditionally, hand drilled explosives or heavy mechanized sources are used for surveying the subsurface. However, in the environmental sensitive areas, the use of explosives is restricted or banned. For those land areas that are difficult to be accessed by vehicles, the challenge of deploying the necessary equipment for producing the seismic waves is high. However, those undertaking the drilling in this area need to know where to drill in order to avoid a dry well.
• Seismic data acquisition and processing generate a profile (image) of the geophysical structure of the target area. While this profile does not provide an accurate location for the oil and gas, it suggests, to those trained in the field, areas where there is a likely presence or absence of oil and/or gas. Thus, providing a high resolution image of the structures (subsurface) under the surface of the Earth is an ongoing process.
• During a seismic gathering process, as shown inFIG. 1, avehicle10 tows aseismic source12 from location to location. At a given location as shown inFIG. 1, theseismic source12 is placed on theground14 such that aplate16 is in direct contact with the ground. Amechanism18 is actuated to drive theplate16 towards theground14 so that a seismic wave is generated. Theseismic wave20 propagates down into the Earth until it is reflected by areflector22. Then areflected wave24 is generated that propagates upward toward thesurface14 of the Earth. Asensor26 may be deployed away from thevehicle10 or next to thevehicle10 to measure thereflected wave24. Based on these measurements that are taken at various locations, a profile of thereflectors22 is determined.
• However, the traditionalseismic sources12 need to be deployed by avehicle10 as they weigh too much to be portable. As the environmentally sensitive areas prohibit or strictly limit the access of heavy duty equipment or vehicles, the existing methods for generating seismic waves are not suitable for these areas. Alternatives sources for generating the seismic waves, e.g., explosives, may also be restricted in these areas. Thus, there is a need to develop a new seismic source that overcomes the above noted problems and drawbacks.
SUMMARY
• According to one exemplary embodiment, there is a portable seismic source for generating seismic waves or energy in the ground. The portable seismic source includes an impact generator device configured to produce impulsive energy; a casing configured to house the impact generator device; a base plate configured to be placed on the ground; and a stabilizing foot mechanism configured to be provided between the casing and the base plate. The stabilizing foot mechanism includes a stabilizer which is fixed relative to the casing and configured to be placed on the base plate and a stanchion that is configured to move relative to the stabilizer when impacted by the impact generator device and to enter through the stabilizer and apply a force on the base plate.
• According to another exemplary embodiment, there is a portable seismic source for generating a seismic source underground. The portable seismic source includes a casing; a combustion chamber provided inside the casing; a piston provided inside the combustion chamber to divide the combustion chamber in a first chamber and a second chamber; compression means provided between the piston and a disk of the casing so that the piston is biased towards the first chamber; a base plate configured to be placed on the ground; and a stabilizing foot mechanism configured to be provided between the casing and the base plate. The piston is configured to prevent air from the second chamber moving into the first chamber through the piston and air from the first chamber moving into the second chamber through the piston.
• According to still another exemplary embodiment, there is a method for generating a seismic wave. The method includes injecting air and fuel in a combustion chamber; igniting the air and fuel to generate a high pressure in the combustion chamber; and displacing a piston provided inside the combustion chamber to transfer momentum to a base plate via a stanchion for generating the seismic wave. The piston divides the combustion chamber in first and second chambers and the piston is configured to prevent air from the second chamber moving into the first chamber through the piston and air from the first chamber moving into the second chamber through the piston.
BRIEF DESCRIPTION OF THE DRAWINGS
• The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate one or more embodiments and, together with the description, explain these embodiments. In the drawings:
• FIG. 1 is a schematic diagram of a conventional land seismic source;
• FIG. 2 is a schematic diagram of a portable seismic source according to an exemplary embodiment;
• FIG. 3 is a schematic diagram of a portable seismic source having a platform according to an exemplary embodiment;
• FIG. 4 is a schematic diagram of a portable seismic source according to another exemplary embodiment;
• FIG. 5 is a schematic diagram of various parts of a portable seismic source according to still another exemplary embodiment;
• FIG. 6 is a schematic diagram of a stabilizer mechanism of a seismic source according to an exemplary embodiment;
• FIG. 7 is a schematic diagram of a base plate and a stabilizer mechanism of a seismic source according to an exemplary embodiment;
• FIG. 8 is a flowchart illustrating a method for generating a seismic wave with a portable source according to an exemplary embodiment; and
• FIG. 9 is a cross-view of a portable seismic source according to an exemplary embodiment.
DETAILED DESCRIPTION
• The following description of the exemplary embodiments refers to the accompanying drawings. The same reference numbers in different drawings identify the same or similar elements. The following detailed description does not limit the invention. Instead, the scope of the invention is defined by the appended claims. The following embodiments are discussed, for simplicity, with regard to the terminology and structure of a portable propane powered seismic source. However, the embodiments to be discussed next are not limited to this structure, but may be applied to other structures that need to apply a force to the ground to provide a seismic source and also be portable.
• Reference throughout the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the subject matter disclosed. Thus, the appearance of the phrases “in one embodiment” or “in an embodiment” in various places throughout the specification is not necessarily referring to the same embodiment. Further, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.
• According to an exemplary embodiment there is a seismic source that is portable and does not require a vehicle to be carried to a desired destination. In addition, the novel seismic source does not use explosives. Thus, this novel seismic source complies with strict environmental requirements and can be transported by one or more persons to the desired location. In one application, the seismic source is a hammer that is activated by a fuel source, e.g., propane.
• According to an exemplary embodiment shown inFIG. 2, aseismic source40 includes acasing42, a stabilizingfoot mechanism44 and abase plate46. Thecasing42 is configured to house an impact generator device which will be discussed later. Thebase plate46 is configured to be placed in direct contact with thesurface48 of the Earth. Thecasing42 includes a power source and a hammer mechanism (to be discussed later) that is configured to act on thebase plate46 for generating the seismic waves. The stabilizingfoot mechanism44 is configured to keep a predetermined distance between thecasing42 and thebase plate46. The stabilizingfoot mechanism44 is provided at a lower end of thecasing42 while an exhaust and intake valve (to be discussed later) are provided at a head orupper end42aof thecasing42.
• FIG. 2 also shows thepower source50 that is attached to theseismic source40 and configured to provide fuel to a combustion chamber. Thepower source50 may be a gas tank, e.g., propane tank. Depending on the impact generator device, thepower source50 may be, alternatively, a combustion source, a pneumatic source, a hydraulic source, an electrical source, etc. Thus, the impact generator device may be, alternatively, a device that generates an impact by combustion means, pneumatic means, hydraulic means, electrical means, etc. In one application, thepower source50 may be provided inside thecasing42. The fuel from thepower source50 is delivered by agas delivery system52 to the combustion chamber. In one application, to be discussed later, a tank of compressed oxygen may be added and provided to the ignition chamber for increasing a power provided to the impact generator device. The fuel is mixed with air and/or the oxygen source as will be discussed later and ignited by anignition control module54.
• Before discussing the details of the combustion chamber and other various elements of theseismic source40, it is noted in another exemplary embodiment shown inFIG. 3 that aplatform60 may be removably attached to thecasing42. Theplatform60 may be made of metal (e.g., steel) and may have multiple purposes. One purpose is to provide a base for the operator of theseismic source40 from where to control the source. Another purpose is to increase a weight of theseismic source40 to counter balance a recoil that is produced in thecasing42 when the fuel is burnt in the combustion chamber and a momentum is transferred to thebase plate46 in a short amount of time.
• For preserving the portability of the entireseismic source40, theplatform60 may be easily removed from thecasing42 and may be carried by another person than the person that carries the remainder of theseismic source40. For illustrative purposes, a weight of theseismic source40 is between 50-100 lbs and a weight of theplatform60 is in the range of 5-15 lbs. Thus, as theseismic source40 may be transported by one person, and theplatform60 may be carried by another person, the novelseismic source40 is totally portable, does not necessarily require a motorized vehicle for transportation and also does not need explosives to function. Theplatform60 is foldable, i.e., may be folded from the position shown inFIG. 3 to a position in which a longitudinal axis of the platform is substantially parallel to a longitudinal axis of thecasing42.
• A cut-through view of theseismic source40 is shown inFIG. 4. This figure shows theplatform60 having twoextensions62 that connect to correspondingpins64 attached to thecasing40. In this embodiment, theplatform60 is not connected to thebase plate46. Theextensions62 have cuts that fit around thepins64. Thus, theplatform60 is easily removable from thecasing42, i.e., no screws or other fixtures or tools are necessary.
• Thecasing42 may be provided with ahandle70 for providing a point of stability to the operator that is on theplatform60 and operates theseismic source40. Inside thecasing42 there is thecombustion chamber72 in which apiston74 is provided.Piston74 divides thecombustion chamber72 into afirst chamber72aand asecond chamber72b. Fuel is handled by the gas delivery system52 (shown inFIGS. 2 and 3). The air/fuel is mixed in thefirst chamber72aas discussed later. Thegas delivery system52 includes solenoid valves that are controlled by a microprocessor control circuit for opening and closing.
• FIG. 5 schematically shows thepower source50 connected to apressure regulator78 and asolenoid valve80 that form thegas delivery system52. Thesolenoid valve80 is controlled by aprocessor82 and is provided with an electrical current from abattery84. The fuel is injected bynozzles86 directly into thefirst chamber72a. The air is provided via avalve90 provided at a top of thecasing42.Valve90 may be a solenoid valve and may be controlled to open and close by theprocessor82. By opening and closingvalves80 and90, the processor can control the combustion mixture air/fuel ratio to optimize the combustion under varying conditions. Optionally, anoxidizer tank160 may be provided to supply an oxidizer fluid to thefirst chamber72afor increasing the power produced by the ignition. The oxidizer fluid may be, for example, compressed oxygen. Similar to the power supply system, apressure regulator162, asolenoid valve164 and anozzle166 may be used to control the flow of the oxidizer fluid into thefirst chamber72a. Thesolenoid valve164 may be connected to thebattery84 and also to theprocessor82.Processor82 may be part of acontrol module92 that may also include amemory94 for storing computer instructions. The computer instructions may be provided to thememory94 via aninterface96. Theinterface96 may include one or more of a port, keyboards, mouse, touch screen, etc. Thecontrol module92 may be configured to operate the power source. For example, for a propane source, thecontrol module92 may be configured to compensate for ambient temperature, pressure, humidity, etc. Further, thecontrol module92 may be configured to control the impact generator device to perform a single impact, a plurality of impacts, a series of impacts with equal or unequal, predetermined time intervals, etc. Thecontrol module92 may be controlled by the operator for choosing one or more of the modes discussed above. For example, a switch may be provided outside thecasing42 that selects one of the modes. Thus, the operator may simply select a desired mode by providing the switch in a corresponding position.
• The control module may also be configured to store (e.g., memory94) information about one or more impacts. This information may be measured, for example, by one or more sensors (see150 inFIG. 6). These sensors may be provided in the base plate. Theinterface96 of thecontrol module92 may be configured to connect to a cable for transferring information to and from an outside seismic recorder unit. In one application, the seismic recorder unit is far away from theseismic source40. In this case, theinterface96 may include wireless communication means (e.g., a transceiver or a transmitter) for transmitting the data to and/or receiving information from the seismic recorder unit.
• In one application, both thenozzles86 and thevalve90 are provided at thehead42aof thecasing42.Plural holes98 are formed through thecombustion chamber72, in thesecond chamber72aso that the exhaust from the burning process is released outside the combustion chamber. Theignition control module54 is shown being connected to one ormore spark plugs100 that are in direct contact with an atmosphere insidefirst chamber72a. Theignition control module54 is also electrically linked to theprocessor82. Thus, theprocessor82 is able to control and coordinate the fuel supply, air intake, and the ignition of the mixture of air and fuel.
• Returning toFIG. 4, the position of thevalve90 is indicated at thehead42a. Thepiston74 is shown in contact with a first end of acompressible means110. The compressible means110 may be, for example, a spring. The compressible means110 has a second end that contacts astarting mechanism112. The startingmechanism112 may include adisk114 that contacts the second end of thecompressible means110.Disk114 is a collar/ring on which the compressible means110 sits.Disk114 may be a collar that freely moves up and down and is constrained from travelling towards the ground by an internal stop, e.g., a snap ring. It is noted that a top cap130 (shown inFIG. 6 and discussed later) goes through thedisk114 and is capable to move relative to thedisk114. Thus, when the device is fired, thepiston74 is accelerated downwards compressing the compressible means110 and ultimately directly contacting thetop cap130. Using ahandle116 the user can raise and lower thepiston74 to purge thecombustion chamber72ain the case of a misfire. Thevalve90 needs to be open to permit this action.Disk114 also acts as a ‘stop’ for the compressible means110 to prevent it from getting pushed out the lower end of thechamber42. Thehandle116 is attached to thedisk114 and thehandle116 is provided outside thecasing42 so that the operator of theseismic source40 may move thedisk114 up by means of slots (seeFIGS. 2,3 an4) incasing42 to initiate the first upward stroke of thepiston74.
• The stabilizingfoot mechanism44 is interposed betweendisk114 andbase plate46 as discussed next. As shown inFIG. 6, the stabilizingfoot mechanism44 is configured to stay on top of thebase plate46. Aflexible material120, e.g., rubber foam, may be inserted between the stabilizingfoot mechanism44 and thebase plate46. This flexible material suppresses most of the noises produced when hammering the stabilizing foot mechanism withpiston74. In other words, whenpiston74 is actuated by the ignition of the fuel in thefirst chamber72a, thepiston74 moves towards the stabilizingfoot mechanism44 and hits thetop cap130. Thus a more accurate seismic wave is generated by thebase plate46. Thebase plate46 may be formed of aluminum and theflexible material120 may be glued to thebase plate46.
• The stabilizingfoot mechanism44 includes thetop cap130 that is configured to interact withpiston74 as noted above. Thetop cap130 may be made of stainless steel. Thetop cap130 continues with astanchion132 that may be made of aluminum. In one application, thetop cap130 is fixedly attached to thestanchion132. Thestanchion132 together withtop cap130 may freely move through thering114. Thestanchion132 is configured to enter astabilizer134 that may be made of aluminum. Thestabilizer134 is configured to be optionally attached to thecasing42. For example, screws may be inserted through the tail end of thecasing42 intoholes136 formed in aneck portion138 of thestabilizer134. Alternately, the weight of the operator standing onplatform60 can be employed to hold thecasing42 in contact with the stabilized134. Thestanchion132 is configured to slide along direction Y relative to thestabilizer134.
• For reducing a frictional force between thestanchion132 and theneck portion138 of thestabilizer134, asleeve140 may be provided inside theneck portion138. Thesleeve140 may be made of Ultra-high-molecular-weight polyethylene (UHMW). Thestanchion132 is welded or attached by other means to thebase plate46. For maintaining thebase plate46 next to theflexible material120, askirt146, as shown inFIG. 7, may be provided between thebase plate46 and a bottom portion of thestabilizer134. Other means may be used for keeping these elements together in a loose manner, as will be discussed later. Theskirt146 may be made of a textile material and it is attached by screws or bolts or pins148aand148bon both thebase plate46 and the bottom portion of thestabilizer134. By being made of a textile material or other elastic material, the activation of thestanchion132 andbase plate46 do not pull thecasing42 along the Y direction. Theskirt146 may be removed so that thebase plate46 can be detached from thestabilizer134. The stabilizingfoot mechanism44 may also include, as shown inFIG. 6, asensor150 mounted to thebase plate46 for detecting an exact moment when thepiston74 strikes thebase plate46 and also to determine a ‘source signature’—or force signature—of the signal that will be transferred to the ground. This could be accomplished by either one (1) or two (2) sensors. Thesensor150 may be electrically connected to theprocessor82 shown inFIG. 5 so that data may be recorded in thememory94.
• An operation of the portableseismic source40 is now discussed with reference toFIG. 8. Instep800, fuel and air is provided in thefirst chamber72a. The fuel intake is controlled by thesolenoid valve80 and the air intake is controlled byvalve90. The mixture of air and fuel is then ignited instep802 by theignition control module54. The burning of the mixture in thefirst chamber72aproduces a sudden increase in pressure and thus, thepiston74 moves along the Y (vertical) direction with a predetermined force that is dictated by the size of the combustion chamber, the type of fuel, the amount of air, etc. Thepiston74, by moving downwards, strikes instep804 thetop cap130 of the stabilizingfoot mechanism44.
• Thestanchion132, by moving downward under the momentum from thetop cap130, forces thebase plate46 to be driven downwards on the ground and so produces a seismic wave instep806. The exhaust produced by the burnt fuel is primarily evacuated from the combustion chamber throughholes98 instep808. The exhaust is also evacuated when thepiston74 moves upwards, in the negative direction of the axis Y. This secondary evacuation takes place through thevalve90 and is coordinated byprocessor82. Air is inserted into thechamber72athrough thevalve90 which acts as a dual purpose air/exhaust port. The intake of air may be naturally aspirated or a mechanism for achieving forced air to assist in the evacuation of exhaust from the chamber above42amay be used. This mechanism may include the use of compressed air or a fan. The secondary evacuation is enhanced by thepiston74 moving upward under the bias provided by the compressible means110. In this regard, it is noted that the compressible means110 were compressed whenpiston74 moved downwards. In step810, the process is repeated for as long as the operator desires, or as programmed into the control circuit.
• The following features of the seismic source are noted. Thepiston74 does not have an internal valve and there is no mechanical means inside thefirst chamber72athat is activated bypiston74 for allowing the air and/or fuel to enter thefirst chamber72a. Theplatform60 attaches to thecasing42 and not to thebase plate46. There is aregulator78 that maintains the pressure of the fuel at a predetermined level when the pressure in thepower source50 decreases. Theseismic source40 may be considered to act as a hammer, i.e., thepiston74 moves downwards to hittop cap130 similar to a hammer hitting the head of a nail. This hammer action may be controlled by the operator to be continuous or in series, i.e., with a controlled time interval between two hammer actions. This interval is programmed into the control circuit.
• One or more of the exemplary embodiments discussed above advantageously provides a seismic source that exhibits a cycle time for 100 hits per 60 s, or maximizes an energy transfer between the piston, base plate and the ground, or improves a bandwidth of the signal to be about 75% of a typical hand drilled dynamite slot, or maintains a low weight so that the whole assembly may be carried by one or two persons, or eliminates secondary events. According to an exemplary embodiment a weight of the whole assembly may be around 50 kg and an average cycle time may be about 600-1000 ms.
• A cross-section view of a fully assembled portableseismic source200 is illustrated inFIG. 9. It is noted that the portableseismic source200 includes thecasing42, thevalve90, thepiston74 that separates thefirst chamber72afrom thesecond chamber72b, the compressible means110, thedisk114, thetop cap130, thestanchion132, thestabilizer134, and thebase plate46. This portableseismic source200 has apin210 that goes through thestanchion132 and theends210aand210bof thepin210 ride up and down inslots212 formed in thestabilizer134. Thus, thebase plate46 does not need theskirt146 shown inFIG. 7 as thebase plate46 is now attached to thestanchion132.
• The disclosed exemplary embodiments provide a portable system and a method for generating a seismic source that propagates underground. It should be understood that this description is not intended to limit the invention. On the contrary, the exemplary embodiments are intended to cover alternatives, modifications and equivalents, which are included in the spirit and scope of the invention as defined by the appended claims. Further, in the detailed description of the exemplary embodiments, numerous specific details are set forth in order to provide a comprehensive understanding of the claimed invention. However, one skilled in the art would understand that various embodiments may be practiced without such specific details.
• Although the features and elements of the present exemplary embodiments are described in the embodiments in particular combinations, each feature or element can be used alone without the other features and elements of the embodiments or in various combinations with or without other features and elements disclosed herein.
• This written description uses examples of the subject matter disclosed to enable any person skilled in the art to practice the same, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the subject matter is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims.

Claims (28)

1. A portable seismic source for generating seismic waves or energy in the ground, the portable seismic source comprising:

an impact generator device configured to produce impulsive energy;

a casing configured to house the impact generator device;

a base plate configured to be placed on the ground; and

a stabilizing foot mechanism configured to be provided between the casing and the base plate,

wherein the stabilizing foot mechanism includes a stabilizer which is fixed relative to the casing and configured to be placed on the base plate and a stanchion that is configured to move relative to the stabilizer when impacted by the impact generator device and to enter through the stabilizer and apply a force on the base plate.

2. The portable seismic source ofclaim 1, further comprising:

a flexible material provided between the stabilizer and the base plate.

3. The portable seismic source ofclaim 2, further comprising:

elastic means configured to maintain the base plate attached to the stabilizer.

4. The portable seismic source ofclaim 1, further comprising:

a pin extended through the stanchion and into the stabilizer.

5. The portable seismic source ofclaim 1, further comprising:

a top cap provided on top of the stanchion; and

at least one sensor attached to the stabilizer and configured to measure a time of contact between a piston and the top cap and/or a force signature of the impact.

6. The portable seismic source ofclaim 1, wherein the impact generator device is one of a pneumatic activated device, a hydraulic activated device, a propane activated device, or an electrical activated device.

7. The portable seismic source ofclaim 1, further comprising:

a combustion chamber provided inside the casing;

the impact generator device includes a piston provided inside the combustion chamber to divide the combustion chamber into a first chamber and a second chamber; and

compression means provided between the piston and a disk of the casing so that the piston is biased towards the first chamber,

wherein the piston is configured to transfer momentum to the stanchion when an ignition occurs in the first chamber.

8. The portable seismic source ofclaim 7, wherein the impact generator device further comprising:

a first valve configured to control an amount of fuel provided to the first chamber;

a second valve configured to control an amount of air provided to the first chamber;

an ignition control module configured to ignite the fuel inside the first chamber; and

exhaust holes provided in the second chamber and configured to release exhaust gases in the atmosphere around the portable seismic source.

9. The portable seismic source ofclaim 8, further comprising:

a control module configured to control a timing of the first valve, the second valve and the ignition control module.

10. The portable seismic source ofclaim 8, further comprising:

a power source connected to the first valve,

wherein the control module is configured to control an operation of the source.

11. The portable seismic source ofclaim 9, wherein the control module is configured to compensate for ambient temperature, pressure, humidity and to perform a single impact, multiple impacts, a series of impacts with equal intervals, or a series of impacts with variable intervals.

12. The portable seismic source ofclaim 9, wherein the control module is configured to store information related to one or more impacts of the impact generator device.

13. The portable seismic source ofclaim 9, wherein the control module is configured to communicate data to and/or receive data from a seismic recorder unit by cable or wireless.

14. The portable seismic source ofclaim 1, further comprising:

a platform configured to be detachably attached to the casing, wherein the platform is also configured to support a weight of a person operating the seismic source.

15. A portable seismic source for generating a seismic source underground, the portable seismic source comprising:

a casing;

a combustion chamber provided inside the casing;

a piston provided inside the combustion chamber to divide the combustion chamber in a first chamber and a second chamber;

compression means provided between the piston and a disk of the casing so that the piston is biased towards the first chamber;

a base plate configured to be placed on the ground; and

a stabilizing foot mechanism configured to be provided between the casing and the base plate,

wherein the piston is configured to prevent air from the second chamber moving into the first chamber through the piston and air from the first chamber moving into the second chamber through the piston.

16. The portable seismic source ofclaim 15, wherein the stabilizing foot mechanism comprises:

a stabilizer which is fixed relative to the casing and configured to be placed on the base plate; and

a stanchion that is configured to move relative to the stabilizer and to enter through the stabilizer and apply a force on the base plate.

17. The portable seismic source ofclaim 16, wherein the piston is configured to transfer momentum to the stanchion when an ignition occurs in the first chamber.

18. The portable seismic source ofclaim 16, further comprising:

a flexible material provided between the stabilizer and the base plate.

19. The portable seismic source ofclaim 16, further comprising:

elastic means configured to maintain the base plate attached to the stabilizer.

20. The portable seismic source ofclaim 16, further comprising:

a pin extended through the stanchion and into the stabilizer

21. The portable seismic source ofclaim 16, further comprising:

a top cap provided on top of the stanchion; and

a sensor attached to the stabilizer and configured to measure a time of contact between the piston and the top cap and/or a force signature of the impact.

22. The portable seismic source ofclaim 15, further comprising:

a first valve configured to control an amount of fuel provided to the first chamber;

a second valve configured to control an amount of air provided to the first chamber;

an ignition control module configured to ignite the fuel inside the first chamber; and

exhaust holes provided in the second chamber and configured to release exhaust gases in the atmosphere around the portable seismic source.

23. The portable seismic source ofclaim 22, further comprising:

a control module configured to control a timing of the first valve, the second valve and the ignition control module.

24. The portable seismic source ofclaim 23, wherein the control module is configured to compensate for ambient temperature, pressure, humidity and to perform a single impact, multiple impacts, a series of impacts with equal intervals, or a series of impacts with variable intervals.

25. The portable seismic source ofclaim 23, wherein the control module is configured to store information related to one or more impacts of the impact generator device.

26. The portable seismic source ofclaim 23, wherein the control module is configured to communicate data to and/or receive data from a seismic recorder unit by cable or wireless.

27. The portable seismic source ofclaim 15, further comprising:

a platform configured to be detachable attached to the casing, wherein the platform is also configured to support a weight of a person operating the seismic source.

28. A method for generating a seismic wave, the method comprising:

injecting air and fuel in a combustion chamber;

igniting the air and fuel to generate a high pressure in the combustion chamber; and

displacing a piston provided inside the combustion chamber to transfer momentum to a base plate via a stanchion for generating the seismic wave,

wherein the piston divides the combustion chamber in first and second chambers and the piston is configured to prevent air from the second chamber moving into the first chamber through the piston and air from the first chamber moving into the second chamber through the piston.

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