Seismic Source Installation/Anchoring System and Method

Abstract

A vehicle hitch or tow bar can be used as an attachment point to a vehicle to provide weight to a seismic source system which includes at least one vibratory seismic source mounted to a shaft of pole and a mechanism for raising and/or lowering the shaft or pole for use in coupling a seismic source to the earth in conjunction with acoustic receivers for determining the lithology and for acoustic imaging of the subsurface of the earth.

Claims

1. A seismic source system apparatus comprising: at least one vibratory seismic source mounted to a shaft or pole; a means of raising and/or lowering the shaft or pole; and a means for attaching the seismic source system to a motor vehicle.

2. The seismic source system according to claim 1 wherein the seismic source is a rotary vibrator.

3. The seismic source system according to claim 1 wherein the seismic source is a linear vibrator.

4. The seismic source system according to claim 1 wherein the seismic source is a rotary vibratory system that produces linear vibratory motion.

5. The seismic source system according to claim 1 wherein the seismic source is a hydraulically-driven piston-reaction mass device.

6. The seismic source system according to claim 1 wherein the shaft or pole has a stiff plate at the lower end.

7. The seismic source system according the claim 6 wherein as the plate at the lower end of the shaft or pole is lowered it eventually makes contact with the earth/ground, and further lowering causes an increasing portion of the weight of the motor vehicle to be transferred to the shaft/plate.

8. The seismic source according to claim 6 further comprising an instrument for measuring and providing an indication of the force holding the plate against the ground.

9. The seismic source according the claim 1 wherein the means of raising and lowering the shaft or pole is via one or more hydraulic actuators.

10. The seismic source according to claim 1 wherein the means of raising and lowering the movable shaft or pole is via one or more electrical actuators.

11. The seismic source according to claim 1 wherein the means of raising and lowering the movable shaft is via a hand operated jacking system.

12. The seismic source according to claim 1 wherein the means of attaching the source system to a motor vehicle is a via a receiver trailer hitch that is affixed to the vehicle.

13. The seismic source according to claim 1 wherein the means of attaching the source system to a motor vehicle is via a tow bar that is affixed to the vehicle.

14. The seismic source according to claim 1 that includes vibration isolators between the vibratory seismic source and the moveable shaft or pole.

15. A seismic source system apparatus comprising: at least one vibratory seismic source mounted to a shaft or pole; a means of raising and/or lowering the shaft or pole; and a means for attaching the seismic source system to a trailer towable by a motor vehicle.

16. A method, comprising the steps of: creating an acoustic coupling between a ground surface and a stiff plate by mounting at least one vibratory seismic source to a movable shaft which is attached both to the stiff plate and to a movable structure; and causing the movable shaft to move so that weight of the movable structure applies a force through the movable shaft to hold the stiff plate against the ground surface; wherein the movable structure is comprised of a motor vehicle or an object towable by the motor vehicle.

17. The method of claim 16 wherein said at least one vibratory seismic source is not permanently mounted to the motor vehicle.

18. The method of claim 16, wherein said at least one vibratory seismic source is not mounted to the movable structure.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] FIG. 1 illustrates a system according to the present invention attached to the front of a typical pickup truck.

[0020] FIG. 2 illustrates a trailer hitch that can provide an attachment mechanism for use with the present invention.

[0021] FIGS. 3 and 4 illustrate to different possible configurations with some details of the present invention, FIG. 3 illustrating where the vibratory seismic source is located above an attachment point relative to a ground plate, FIG. 4 illustrating where the vibratory seismic source is located below an attachment point relative to a ground plate.

[0022] FIG. 5 is similar to FIG. 2, although it also illustrates use of a vibration isolator.

[0023] FIG. 6 illustrates a tow bar that can provide an attachment mechanism for use with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0024] For this invention a vibratory seismic source is mounted on a moveable shaft that is attached to the front or back of a standard pickup truck, sport utility vehicle, or other work vehicle preferably via a standard receiver trailer hitch. In the preferred embodiment, the vibratory seismic source/moveable shaft assembly are designed to be easily removable from the hitch assembly when not in use (i.e., highway traveling, etc.) The moveable shaft can be raised or lowered manually (similar to a car jack), via hydraulic actuator. The bottom of the moveable shaft includes a stiff plate, designed to provide the acoustic coupling to the earth. As the plate is lowered for operation of the seismic source, it will eventually contact the earth/ground. As it is lowered further, a portion of the weight of the vehicle will be transferred to the plate. Thus the weight of the vehicle provides the counterweight to ensure good seismic coupling with the earth. Once the desired amount of force is achieved, the position of the shaft will be locked in place, and the seismic source energized.

[0025] FIG. 1 illustrates a vibratory seismic source (labelled MicroVib) mounted at the top of the moveable shaft. The source can be mounted at the top, bottom, or anywhere in-between on the moveable shaft. A front-mounted receiver trailer hitch provides the attachment method for the system to the vehicle. An example of such a hitch is shown in FIG. 2.

[0026] FIGS. 3 and 4 are possible configurations with some of the details of a system in accordance with the present invention. The locations for the seismic source, hydraulic actuator, etc., are provided as examples only. One skilled in the art realizes that they can be rearranged to multiple other locations without affecting the operation of the system. And, a hydraulic actuator system is shown, however, as stated previously, this represents just one possible means of moving the shaft. A receiver trailer hitch is an especially preferred method for attaching the system to a motor vehicle, however, another option is to use a tow bar at the front of the motor vehicle.

[0027] While the invention has been described herein with reference to certain preferred embodiments, those embodiments have been presented by way of example only, and not to limit the scope of the invention. Additional embodiments thereof will be obvious to those skilled in the art having the benefit of this detailed description.

[0028] Accordingly, it will be apparent to those skilled in the art that still further changes and modifications in the actual concepts described herein can readily be made without departing from the spirit and scoped of the disclosed inventions.