CN1003057B - Wide frequence range underwater coupling shock source array and application - Google Patents
Wide frequence range underwater coupling shock source array and application Download PDFInfo
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Abstract
Three or more marine seismic sources (1-4) are positioned with critical inter-source spacing (D) to produce, when fired in the water, an acoustic pulse whose ''primary to bubble ratio'' for a given recording band width is substantially maximized. The sources of the array are adapted and positioned so that each produces when fired a bubble of substantially equal maximum radius (R). In one preferred embodiment, the array includes four sources positioned approximately at the vertices of a square having side length equal to 2ROOT 2 R, where R is the maximum radius of the bubble that would be produced by each source in the array if fired alone. In all embodiments, the critical spacing between each source and the source nearest thereto will be not less than 1.2 times the maximum bubble radius and not greater than the quantity 2R. In another embodiment, two or more sets of sources are employed, with the sources in each set being positioned and oriented in the water to produce when fired bubbles of substantially equal maximum radius, and such that each source in each set is separated from the other sources nearest thereto in the set by the critical spacing.
Description
Put it briefly, the present invention is relevant with seismic prospecting.More particularly, the present invention relates to focus array in a kind of water of forming by the some single focus of an apart critical distance, also relate to the method that focus in the some water that utilize apart such critical distance produces seismic pulse.
In water during seismic prospecting, be placed on one or several focus in the water body and ignite, make it Xiang Shuizhong and discharge acoustic energy, thereby produce seismic pulse, vibration wave in other words.Propagate in their subsurface geology rock stratum below water body.These pulses are through propagating in the geological formations of water body below water body and reflecting with the sound wave form.An array of being made up of wave detector, nautical receiving set or other similar devices detects these reflective sound waves and converts them to electric signal.These electric signal are noted the usefulness that is provided with the post analysis explanation.Can draw the structure of subsurface geology rock stratum and the oil storage body in these rock stratum by analysis to these tracer signals.
The implication that reaches in the claims " water " word that uses here comprises that the natural pond selects the water in water, mud, low, the wetland, thereby and contains any other liquid that enough water can be operated focus in the used water of the present invention therein.
In the method for seismic prospecting of a kind of land, focus in the water is placed in the on-swimmer's pool or suction pit that uses in the drilling operation at ordinary times.Detect the reflective sound wave pulse that focus produces in the water by being placed on ground wave detector.In near also can being placed on wave detector the wellhole.In a variant of this technology, come the detection of reflected sound wave pulse by the nautical receiving set that is placed in pond or the suction pit.
Many focus in traditional water of water body generation sound wave pulse that are used for are arranged.For example, can utilize explosive (as trinitrotoluene) to produce the high power pulse that enters rock stratum under the water body.Focus is the group capacitor discharge that utilizes by a undersurface electrode in another kind of traditional water, produces an explosive bubble that immediately disappears.When the method for this generation sound wave pulse is used in hope usually when the near surface geological formations obtains the response of high resolution.
Using damp (for example potpourri of propane and AIR MIXTURES or propane and oxygen) to produce in the water of sound wave pulse focus when igniting is admitted widely.The main type of explosive air gun comprises: (1) its working method is to ignite combination gas in the back of a flexible baffle, and this dividing plate contacts with water, thereby produces sound wave pulse.US-3800907 has provided a kind of vibrating membrane structure of the displaceable of using in seismic oscillation transmission, specifically, a kind ofly be used to transmit the metal of the strong energy pulse that the seismic origin produces or synthetic vibrating membrane; (2) its method of work is that the bubble that allows gas burst produce directly imports in the water.Before a kind of description of an example of air gun see 3,658, No. 149 patents of the U.S. that were presented to people such as Neal on April 25th, 1972, the description of a kind of air gun example is then seen and was presented to the United States Patent (USP) 4,193,472 of Kirby on March 18th, 1980.
Utilize gases at high pressure to replace the various sound wave energy of explosive mixed gas also to be admitted widely in industry member.The modular design of opening exhaust compressed air gun was issued 3,653, No. 460 patents of the U.S. of Chelminski and was issued 4,141, No. 431 patents of the U.S. of Baird on February 27th, 1979 on April 2nd, 1.A typical compressed air gun that is used for the water seismic prospecting comprises an outer cover, and it contains an air chamber, is used under high pressure closing amount of compressed gas.Air chamber is equipped with a valve, and when the pressure in the air chamber increased, this valve was closed.In case air gun is by " ignition ", valve is promptly opened rapidly, so pressure gas is expanded outwardly from air chamber, enters surrounding medium through the vent port on the outer cover, thereby produces a sound wave pulse.
A kind of special compressed air gun-air cannon-be widely used as seismic energy source in the water.Typical air cannon has above-described compressed air gun structure, and the compression gases at high pressure that only are to use are air.In typical case, the pressurized air in this air cannon produces in being discharged into water and keeps before the required sound wave pulse its pressure 2000 to 6000 pounds/square inch level.
Habitual air cannon generally includes a cylindrical sleeve, and the plurality of rows pore is arranged above, and when the valve open in the air gun, pressure gas just discharges by these vent ports.These under water the vent structure of compressor gun can be diversified.In a kind of general structure, 4 vent ports are arranged on the surface of compressed air gun cylindrical sleeve symmetrically.The PAR that can buy from Bai Er stunt art company (Bolt Technolgy Inc. is located at the Norwalk of the Connecticut State)
Air cannon is the example that the air cannon of 4 symmetrical distribution vent ports is housed.In another kind of structure, by a vent port release pressurized air that extends 360 degree around the compressed air gun periphery.The examples of air cannon that this 360 degree vent ports are housed are the outer bell-type air cannons by geophysics service company (Geophysical Services Inc. is located at the Dallas in De Kelongsi state) design.Outside in the bell-type air cannon, one is slided along sleeve outer surface with the coaxial reciprocating type valve of air gun sleeve, in order to open and close this 360 degree vent port.
The array of forming with two or more underwater sources finishes that seismic prospecting has had history for a long time in the water.For example, 3,437, No. 170 patents of the U.S. that were presented to people such as Brock on April 8th, 1969 have been described the technology of focus in some water of igniting simultaneously in the array.According to people's such as Brock technology, the shape of the energy frequency spectrum of the acoustic signals that is produced by this array is to be determined by the bubble that each focus place produces.Have some to merge in these bubbles, other then do not merge.The bubble that each merging forms produces one and is different from the spectrum component that those single isolated bubbles of being merged into this bubble can produce in energy frequency spectrum.People such as Brock do not disclose any method and improve the inhibition ability of any bubble persistent oscillation intensity that is produced (for the intensity of the initial component of the acoustic signals that is produced or " primary " component).Particularly Brock etc. had not both given advice and had not advised any best critical focus spacing that can improve primary component with the ratio of the strong component amplitude of the persistent oscillation of association of the signal that produces yet.In this article, this amplitude ratio will be called " primary with bubble amount estranged than " (" primary to bubble ratio ") sometimes.
Proposed some array design, be intended to suppress secondary bubble oscillation with respect to the primary signal that is produced.For example, be presented to the U.S. 4 of Ruehle May 10 nineteen eighty-three, 382, No. 468 patent has been described a kind of air gun arrays, the volume ratio in space between selected air cannon and rifle in this array, with the noise that reduces to be produced by secondary bubble oscillation, the constraint condition that need satisfy is that the yardstick of whole array wants enough little so that constitute one " point source " simultaneously.Ruehle proposes, and the distribution of each air gun should make its spacing enough big in the array, does not interact so that consequent each bubble is separate.He also proposes, and should select the air cannon volume ratio according to a specific equation, so that with array " tuning ", thereby forces down because the noise that bubble oscillation produces.
Also proposed another kind of array design, it uses a plurality of single air cannons and a plurality of rifle group that is made of the isometric(al) air cannon simultaneously, and each air gun is each other at a distance of enough near, so that the bubble merging that each air gun produces in rifle group in each rifle group.Primary and the bubble amount estranged of the sound wave pulse that this design produces is the single air cannon of each single rifle volume sum in the rifle group acoustic signals of giving birth to primary and steep amount ratio estranged when replacing each rifle group than having surpassed with volume.When describing this design, point out,, must unite and use some single air cannons and some rifle groups in order to improve the overall response of array.Understand this class array, can consult article " air gun arrays designed system the method " (geophysical survey of B.F.Giles etc., 21, the 77-101 page or leaf, 1973) and W.R.Cotton " application in the focus array in water of outer bell-type air gun " (, reading out in the 46th meeting of the Europe exploration gelphysicist association that in June, 1984,19-22 held) in the London.Yet, prior art never discloses or advises even also do not know the following fact so far: be suitable for producing the focus of the essentially identical bubble of its maximum radius at a distance of the critical distance described in a application if make, the sound wave pulse that is produced will have the very high primary and bubble amount estranged that never reckons with than (hereinafter with under the condition that describes in detail so, when recording frequency band is the 5-880 hertz, can reach 49: 1), and particularly useful for the seismic prospecting of laying focus at superficial part (for example the degree of depth is less than 10 feet).
Be presented to Blake on November 27th, 1956, described the another kind of array design that reduces secondary bubble oscillation in 2,771, No. 961 patents of the U.S. of Jr..Blake, the array of Jr. comprise two explosive sources with definite relative potential ratio, and separately two shot bubbles merging that enough big distance is produced to prevent are perpendicular to one another.Blake, Jr. point out that the best vertical interval D of these two explosive sources should satisfy relational expression (A
1+ A
2)≤D≤3/2(A
1+ A
2), A here
1Equal the shot bubble maximum radius that first explosive source produces, and A
2Equal the shot bubble maximum radius that second explosive source produces.Blake, Jr. point out that this array constitutes the energy that will make secondary bubble oscillation owing to the interaction between two shot bubbles and disappears.By Blake, the explosive source array that certain vertical interval is arranged that Jr. proposes is unsuitable for the exploration operation in shallow water; For those exploration operations that requires broadband signal (its main energy component is in up in 250 hertz the frequency range), this array can not produce suitable acoustic signals.
Focus array comprises focus in three or more the water in the water of the present invention, and they are suitable for locating in water body, to produce the bubble with basic maximum radius R that equates when igniting.Each of other focus that each focus is nearest with it is all at a distance of a selected critical distance D, makes the primary and bubble amount ratio estranged of the signal that this array produces reach maximum value.In all embodiments, the D value will be not less than 1.2R, be not more than 2R.We are characterized by " intercoupling " (" interdependent's ") to the focus that separates with critical gap in institute's invention array.In an optimum implementation, comprise four focus in the array, APPROXIMATE DISTRIBUTION is about a length of side
On foursquare four summits of R.In another optimum implementation, array comprises three focus, and APPROXIMATE DISTRIBUTION is having two length of sides to be similar to
On the summit of the level triangle of R.
When producing bubble less than 10 inches source depth, the method advantageous particularly of in above-mentioned array, igniting each focus simultaneously of the present invention.
Fig. 1 is a skeleton view of implementing focus array in the water of the present invention.This array comprises four to each other apart from being the air cannon of required critical distance and the framework that is used for fixing air cannon.
Fig. 2 provides the time domain characteristic curve of a sound wave pulse.This sound wave pulse is that the array that an optimum implementation according to the present invention is made up of four air cannons produces.The volume of each air cannon is 40 cubic inches, ignites under 2000 pounds/square inch pressure, and 5 feet depths produce bubble in water body.
Fig. 3 provides the frequency field family curve of the sound wave pulse that same an array of being used to produce the pulse that is characterized by Fig. 2 produces when operation.
Fig. 4 is the simplified perspective view of the another embodiment of array of the present invention.This array comprises four groups of focus, and every group has four focus.Each four source group all is the array of type as shown in Figure 1.
Fig. 5 is a synoptic diagram, and drawing maximum radius is four bubbles of R, and each bubble all is to be produced by the ignition of focus in the water in a kind of embodiment of array of the present invention.Comprise four focus in this scheme, be distributed in length of side D and equal
On foursquare four summits of R.
Equipment of the present invention comprises focus in three or more the water, and when focus being arranged in the array of the present invention and detonate in a certain water body, each focus all is applicable to and produces the bubble that maximum radius is R.That can buy on the market has the basic volume that equates and can make the interior gas of rifle reach the air cannon of basic phase pressure applicable to optimum implementation of the present invention.Array implement scheme of the present invention shown in Figure 1 comprises the air cannon (being designated as air cannon 1,2,3 and 4) that four this volumes equate substantially.Each air cannon comprises one or more vent ports 10, so that gas discharges along all directions outside the air gun Y.Flange (flange) 12 stretches out from each air gun, is used for an air gun is linked to each other with other air guns, or links to each other with support 5.As shown in FIG., similar support parts such as chain 8 or cable are installed among every pair of flange 12, are used for air gun 1-4 is linked together, and similar support parts such as chain 6 or cable are installed between flange 12 and 14, stretch out from support 5, air gun 1-4 and support 5 are coupled together.Support 5 can be used in a certain holder (storage as canoe, barge, the buoyancy aid that links with the anchor chain and the bottom, buoyancy aid, dock, protruding dike or the harbour etc. of free-floating) in the water and links to each other, and support 5 is remained on the desired position with respect to the water surface.Sometimes will be called " fixing device " (" positioningunit ") to support 5, chain 6 and chain 8 and flange 12 and 14 altogether hereinafter.Obviously, the fixing device of other many types can be arranged also, be used for making array air gun remain on needed relative position each other and with respect to the water surface.
Fixing device should have suitable size, and has suitable orientation with respect to the water surface, be approximately equal to the bubble of R so that each focus in the array produces a maximum radius in water when igniting, and make the spacing of each nearest focus in each focus and its array equal critical distance D.Preferably include four focus in the embodiment of Fig. 1, be placed in foursquare four jiaos, the spacing of each focus and other nearest focus is critical distance D, and its value is approximately equal to 2R.In this embodiment, this foursquare orientation is in the water on the same degree of depth L initial center position of the bubble that is produced.
The initial center of each bubble that the focus in the array of the present invention produces is also nonessential in (promptly on the same degree of depth) on the same surface level.On the contrary, each focus is in position in the water when igniting should make the difference of degree of adding of initial center position of each single air gun enough little, so that the maximum radius of each bubble that is produced is basic identical, and this scope of the present invention just.For example, be exactly the interior example of the scope of the invention below; Utilize 1 array same as shown in Figure 1, the longitudinal axis of rifle 1 and rifle 2 (vent port 10 is a center line with this axle) is on the degree of depth different with the longitudinal axis of rifle 3 and rifle 4, and the maximum radius of each bubble of generation is basic identical.Another belongs to the embodiment of the scope of the invention: utilize one to similar array shown in Figure 1, when igniting, rifle 1,2,3 and 4 vent port 10 all is that the maximum radius of each bubble that is produced is basic identical on the essentially identical degree of depth.
We find, in the embodiment depicted in fig. 1, the sound wave pulse that is produced by focus array of the present invention is not subjected to the influence that one or several air gun rotates in the array basically, after rotating, the distance between the bubble initial center that the residing reposition of each air gun can guarantee to be produced is preceding basic identical with rotation.
The size that is appreciated that the largest air bubbles radius R depends on a plurality of parameters, comprises the various characteristics of focus in bubble initial center degree of depth L and the used water.Can expect that other focus except that air gun also can be used in the equipment of the present invention.In a kind of optimum implementation of using air cannon, the size of R depends on the air chamber volume in the current mode that everybody knows and the pressure in the air chamber when being about to ignite.For example, can consult by the associating member of manager office of geophysics company (United Geophysical Corporation) and edit, " the nineteen sixty-eight seismic energy source handbook " delivered in the 38th annual meeting of exploration gelphysicist association of holding in Denver, the state of Colorado in October nineteen sixty-eight wherein explained and how to have been estimated the largest air bubbles radius R by known air cannon characteristic.
We find, be 40 cubic inches, be inflated to four arrays that outer bell-type air cannon is formed of 2000 pounds/square inch that the optimum array structure of 5 feet depths operations (thereby the bubble initial center that makes generation is positioned at about 5 feet depths) is that focus is placed on the about 22 1/2 inches square vertices of the length of side in water by the hyperbaric chamber volume.Table 1 provides this array estimated value (its recording frequency band width is the 5-880 hertz) of the average primary and bubble amount ratio estranged when 20,15,10 and 5 feet depths operations respectively.
| The degree of depth (foot) | Ignite |
1,2 and 3 | 1 and 2 | 1 and 3 | 1 |
| 2015105 | 12132545 | 10121728 | 9101320 | 571013 | 34610 |
Being used for generation table 1 array of data is type shown in Figure 1, but replaces each 4 hole air cannon among the figure with outer bell-type air gun.The data that left column comprises in the table 1 are the results that obtain when igniting whole four air guns shown in the array simultaneously.The data that comprise of secondary series are the results that only ignite 1,2 and No. 3 air gun (air gun of press among Fig. 1 is numbered) simultaneously from left to right.Similarly, other each row comprise and ignite air gun 1 and 2,1 and 3 and the result when only igniting air gun 1 simultaneously.Array be placed on orientation in the water be make each air gun the longitudinal axis vertically, the vent port of each air gun all is placed on the same plane of designated depth.
Fig. 2 has represented in order to collect the time domain characteristic that table 1 data are placed on the air gun vent port sound wave pulse that produces when 5 feet depths are ignited the array air gun simultaneously.Passage of time (with millisecond meter) after transverse axis is represented to ignite, igniting constantly is the t=100 millisecond.Curve representation is positioned at acoustic signals pressure that the detecting device of 183 meters depths below the focus array receives over time, if its value normalizes to apart from being the equivalent pressure of 1 meter when measuring by industrial mode commonly used.
Fig. 3 provides the frequency field characteristic of a sound wave pulse, and this sound wave pulse and the pulse that provided time domain characteristic by Fig. 2 are by producing in same mode with an array.Especially meaningfully, spectral amplitude shown in Figure 3 demonstrates a level and smooth broadband.We find, preferably the air cannon in the array of being invented are placed on the depths that is no more than 10 inches and ignite, so that obtain being better than the time sense of conventional air gun arrays.For the shallow like this degree of depth, will can not occur unusual sinking on 250 hertz the frequency being lower than, and 1 millisecond of record is to be the receptible standard minimal value of optimum utilization focus array.
Fig. 5 draws the synoptic diagram of four bubbles that overlap each other, and each bubble here all is to be produced by a focus in the embodiment of igniting array of the present invention.The bubble that shows among the figure is just in moment of the maximum radius R that has expanded.Focus in Fig. 5 array is laid in the length of side and equals
On foursquare four summits of R.Overlapping zone by bubble is not difficult to find out that if four focus in the array are ignited basically simultaneously, four bubbles that produced will take place by significant the interaction.
The focus number is not equal to four array and also belongs in the scope of the invention in the water.For example, three focus in an optimum implementation, have been utilized, the bubble that each can produce a maximum radius is R in water.This with aforementioned different optimum implementation in, three focus are by a fixing device support, make it each and produce the bubble that maximum radius is R when igniting, and focus have been placed on two length of sides and are
Near the vertex of a triangle of R.Following proposal also belongs to the scope of the invention; The bubble initial center position that the installation position of these three focus makes it to produce when igniting is near leg-of-mutton three summits, and this triangle has at least the length D on two limits to be in 1.2R≤D≤2R scope.
An optimum implementation of three focus arrays can realize by removing an air gun in the array shown in Figure 1 and igniting other three air guns simultaneously.Four air guns in array shown in Figure 1 are only ignited three simultaneously, and the 4th do not ignited, and this point also belongs within the scope of the invention.If can keep distance between previously described best rifle, just can strengthen inhibition ability to secondary pulse.For example, the secondary series data show in the table 1, equal 28: 1 with the primary of three resulting pulse signals of rifle scheme of the present invention and bubble amount ratio estranged.
Also within the scope of the invention, here, the location of the focus in the array, producing equal-volume bubble (maximum radius is R), and the spacing of each focus and other nearest focus is a critical distance as described herein in the array more than the array of four focus in use.In one embodiment, six focus are arranged in two parallel row, three focus of every row, and the spacing of each focus and other nearest focus is about
R.
The type that the best critical distance of every kind of embodiment depends on the concrete property of focus and is used for focus is fixed on the fixing device of desired location.When operation, for a given array, be preferably in 1.2R and the 2R scope (comprising 1.2R and 2R) to select between different sources distance to carry out several groups of continuous coverages, thereby determine best critical source spacing from.For given recording frequency band width, when getting best critical gap, will reach maximum primary and bubble amount ratio estranged.
Utilization comprises that the array of two " groups " or many " group " focus also is within the scope of the present invention, wherein every group of concrete enforcement that focus all is an array of the present invention.For example, comprise four groups of focus in the scheme shown in Figure 4, every group all is four focus type arrays shown in Figure 1.First group of focus comprises focus 111,112,113 and 114.Other three groups of focus comprise 115-118,119-122 respectively, reach 123-126.These focus are fixed on the desired location with respect to framework 110 by chain 130 and chain-like thereof, and focus group chain 131 and chain-like thereof in every group are fixed on the needed position toward each other.
In a kind of variant of Fig. 4 scheme, its array comprises the approximately equalised air cannon of volume, and they are inflated to approximately equalised pressure.The orientation of array in water should make the initial center degree of depth of the bubble that focus produces within an enough narrow scope, thereby makes the maximum radius of the bubble that each single focus produces in the array basic identical.In another kind of scheme, every group of focus of array is approximate isometric air gun, (volume and the pressure of respectively organizing air cannon can differ from one another to be inflated to approximately equalised pressure, also identical volume and pressure can be arranged), and the yardstick that each group is fixed on the fixing device on the certain position is different from device shown in Figure 4, make the mean depth of the bubble that first group of focus produce be different from the mean depth of the bubble that second group of focus produce.In the scheme of this a kind of distortion in back, the bubble that is produced by first group of focus can have different maximum radius with the bubble that second group of focus produces, and also identical maximum radius can be arranged.Below this also be within the scope of the present invention: each group can comprise various dissimilar focus (as not isometric air cannon), as long as the bubble that produces when each focus is ignited in each group has essentially identical maximum radius (maximum radius of each group can be different), and the focus spacing in every group is the critical distance corresponding to the largest air bubbles radius.The length that connects the frame part 160 of each focus group preferably can enough be lacked, so that array has the characteristic of point source.In some applications, the length of framework ingredient 160 can be selected to such an extent that make each focus group separate basically.
The maximum radius of the bubble that each focus group produces can be identical, also can each group differ from one another.In one embodiment, utilize many group air cannons, the air cannon that each group comprises has same volume, and the ratio of respectively organizing the volume of air cannon can be determined according to any known air gun arrays " tuning " technology.
In implementing any array approaches as described herein, thereby the sound wave pulse of bubble oscillation has been depressed (these sound wave pulses are almost to ignite the focus that closes mutually in the array simultaneously to produce in water) with respect to the primary pulse height of sound wave pulse has made the amplitude of the downward Propagation of Energy of primary pulse reach maximum value.For example, in a kind of embodiment of array of the present invention, three groups of focus are arranged, each group is placed degree of depth difference, but makes the bubble center degree of depth that produces when respectively group is ignited in 10 feet scopes, and focus is preferably in the selected moment ignition in about 2 milliseconds of time periods.In this example, the placement location of three groups of focus makes the center of the bubble that is produced respectively at degree of depth L, L-5 foot and L+5 foot, and each is organized and preferably ignites successively with 1 ms interval.
Claims (12)
1, a kind of method that in water body, produces seismic pulse, implementation step comprises:
(a) in water, arrange focus in one group of water of at least three, each focus is suitable for producing the bubble that a maximum radius is substantially equal to R in water, its focus is placed on the appropriate depth, so that each focus produces the bubble that maximum radius is R when igniting, its focus is the identical substantially air cannon of gas chamber volume, and these air cannons are worked under the pressure that equates substantially;
(b) ignite each focus basically simultaneously in water, to produce a seismic pulse;
It is characterized in that, it is critical distance D to this distance of organizing each nearest with it in focus focus that the layout of focus makes each focus, here 1.2R≤D≤2R, the selection of D value enables fully to reach with respect to its primary pulse and suppresses to greatest extent owing to ignite the back persistent oscillation of these sound wave pulses that focus produces.
2, comprise four according to one group of focus the process of claim 1 wherein, our laying mode makes that the center initial position of consequent four bubbles is approximate and is in foursquare four summits.
3, according to the method for claim 2, wherein distance D is approximately equal to value
R.
4, according to the method for claim 1, one group of focus wherein comprises three focus, their laying mode makes that the center initial position of consequent three bubbles is approximate and is in leg-of-mutton three summits that this triangle has at least the length of side on two limits respectively to equal
R.
5, a kind of underwater seismic air gun arrays comprises:
One group of air cannon of at least three, each air cannon can be to produce the bubble under water that a maximum radius is substantially equal to R in the water of M in the degree of depth; A fixing device is used for air cannon is fixed to basically the non-colinear array of determining of being made up of isolated air cannon, and making each rifle and other spacing of two rifles on it is D, here 1.2R≤D≤2R; A device that is used for described stationary installation is remained on the substantially constant degree of depth.
6, underwater seismic air gun arrays according to claim 5, wherein M≤10 foot.
7, underwater seismic air gun arrays according to claim 5, array wherein comprises at least four air cannons, its fixing device is used for air cannon is fixed on the foursquare summit that the length of side is D.
8, underwater seismic air cannon according to claim 5, wherein D is approximately equal to
R.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US74533385A | 1985-06-14 | 1985-06-14 | |
| US745,333 | 1985-06-14 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN86103768A CN86103768A (en) | 1986-12-31 |
| CN1003057B true CN1003057B (en) | 1989-01-11 |
Family
ID=24996265
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN86103768A Expired CN1003057B (en) | 1985-06-14 | 1986-06-12 | Wide frequence range underwater coupling shock source array and application |
Country Status (9)
| Country | Link |
|---|---|
| JP (1) | JPH0713660B2 (en) |
| CN (1) | CN1003057B (en) |
| AU (1) | AU580422B2 (en) |
| CA (1) | CA1263470A (en) |
| ES (1) | ES8801735A1 (en) |
| FR (1) | FR2583525B1 (en) |
| GB (1) | GB2176605B (en) |
| NL (1) | NL190995C (en) |
| NO (1) | NO169566C (en) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4858205A (en) * | 1988-08-24 | 1989-08-15 | Halliburton Geophysical Services, Inc. | Multi-barrel air gun module |
| GB9920593D0 (en) * | 1999-09-02 | 1999-11-03 | Geco Prakla Uk Ltd | A method of seismic surveying, a marine vibrator arrangement, and a method of calculating the depths of seismic sources |
| GB2393513A (en) * | 2002-09-25 | 2004-03-31 | Westerngeco Seismic Holdings | Marine seismic surveying using a source not having a ghost at a non-zero frequency |
| GB2400662B (en) | 2003-04-15 | 2006-08-09 | Westerngeco Seismic Holdings | Active steering for marine seismic sources |
| US7489590B2 (en) * | 2005-04-08 | 2009-02-10 | Westerngeco L.L.C. | Method and apparatus for source and receiver side wave field separation |
| US9025417B2 (en) | 2010-08-24 | 2015-05-05 | Westerngeco L.L.C. | Systems and methods for optimizing low frequency output from airgun source arrays |
| GB2490787B (en) | 2011-05-11 | 2015-02-11 | Cggveritas Services Sa | Compact broadband source and method |
| NL2016387B1 (en) * | 2016-03-08 | 2017-09-27 | Fugro N V | Seismic source array and survey ship |
| CN106443764B (en) * | 2016-10-17 | 2020-02-11 | 辉禄美（北京）科技有限公司 | Prying type seismic source module |
| CN112180432B (en) * | 2020-09-01 | 2023-10-20 | 中国科学院深圳先进技术研究院 | High-efficiency electric spark source system based on corona discharge and setting method |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB688384A (en) * | 1949-07-02 | 1953-03-04 | Charles Frederick Urschel | Improvements in or relating to apparatus for seismic prospecting |
| US3437170A (en) * | 1966-12-12 | 1969-04-08 | Texas Instruments Inc | Control of energy spectrum in marine seismic exploration |
| NO144253C (en) * | 1975-02-28 | 1981-07-22 | Mobil Oil Corp | PROCEDURE AND SYSTEM FOR SEISMIC INVESTIGATIONS |
| GB1542261A (en) * | 1976-04-07 | 1979-03-14 | British Petroleum Co | Method of operating a seismic source |
| US4382486A (en) * | 1981-02-05 | 1983-05-10 | Mobil Oil Corporation | Tuned air gun array |
| EP0066423B1 (en) * | 1981-05-29 | 1988-01-13 | Britoil Plc | Method of determining the signatures of arrays of marine seismic sources, and of accumulating data for use in such methods |
-
1986
- 1986-02-17 NO NO860575A patent/NO169566C/en unknown
- 1986-05-21 CA CA000509617A patent/CA1263470A/en not_active Expired
- 1986-06-10 GB GB8614037A patent/GB2176605B/en not_active Expired
- 1986-06-12 CN CN86103768A patent/CN1003057B/en not_active Expired
- 1986-06-13 ES ES556022A patent/ES8801735A1/en not_active Expired
- 1986-06-13 JP JP61138033A patent/JPH0713660B2/en not_active Expired - Lifetime
- 1986-06-13 FR FR868608563A patent/FR2583525B1/en not_active Expired - Lifetime
- 1986-06-13 AU AU58728/86A patent/AU580422B2/en not_active Ceased
- 1986-06-16 NL NL8601549A patent/NL190995C/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| NL8601549A (en) | 1987-01-02 |
| ES8801735A1 (en) | 1988-02-16 |
| GB8614037D0 (en) | 1986-07-16 |
| AU5872886A (en) | 1986-12-18 |
| NO169566B (en) | 1992-03-30 |
| NO860575L (en) | 1986-12-15 |
| CA1263470A (en) | 1989-11-28 |
| AU580422B2 (en) | 1989-01-12 |
| FR2583525A1 (en) | 1986-12-19 |
| NL190995B (en) | 1994-07-01 |
| NL190995C (en) | 1994-12-01 |
| JPS61290380A (en) | 1986-12-20 |
| CN86103768A (en) | 1986-12-31 |
| FR2583525B1 (en) | 1990-03-02 |
| GB2176605A (en) | 1986-12-31 |
| ES556022A0 (en) | 1988-02-16 |
| JPH0713660B2 (en) | 1995-02-15 |
| NO169566C (en) | 1994-04-18 |
| GB2176605B (en) | 1989-07-12 |
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