WO2011103331A1 - Transducteurs sismiques dotés de semelles polygonales améliorées et procédés pour leur utilisation - Google Patents

Transducteurs sismiques dotés de semelles polygonales améliorées et procédés pour leur utilisation Download PDF

Info

Publication number
WO2011103331A1
WO2011103331A1 PCT/US2011/025302 US2011025302W WO2011103331A1 WO 2011103331 A1 WO2011103331 A1 WO 2011103331A1 US 2011025302 W US2011025302 W US 2011025302W WO 2011103331 A1 WO2011103331 A1 WO 2011103331A1
Authority
WO
WIPO (PCT)
Prior art keywords
baseplate
seismic
polygon
transducer apparatus
lower plate
Prior art date
Application number
PCT/US2011/025302
Other languages
English (en)
Inventor
Peter M. Eick
Joel D. Brewer
Shan SHAN
Original Assignee
Conocophillips Company
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US13/027,982 external-priority patent/US8167082B2/en
Application filed by Conocophillips Company filed Critical Conocophillips Company
Publication of WO2011103331A1 publication Critical patent/WO2011103331A1/fr

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • G01V1/00—Seismology; Seismic or acoustic prospecting or detecting
    • G01V1/02—Generating seismic energy
    • G01V1/143—Generating seismic energy using mechanical driving means, e.g. motor driven shaft
    • G01V1/155—Generating seismic energy using mechanical driving means, e.g. motor driven shaft using reciprocating masses

Definitions

  • the present invention relates generally to methods and systems for inducing seismic vibrations into an elastic medium. More particularly, but not by way of limitation, embodiments of the present invention include methods and systems for inducing seismic vibrations into subterranean formations utilizing improved seismic baseplates.
  • the reflected seismic waves are detected at the surface by a group of spaced apart receivers called geophones, accelerometers, seismometers or similar transducers. These transducers are collectively referred to as "geophones" herein following industry convention, but it is understood that they could be any sensor that converts seismic energy into some readable data.
  • the reflected seismic waves detected by the geophones are analyzed and processed to generate seismic data representative of the nature and composition of the subterranean formation at various depths, including the nature and extent of hydrocarbon deposits. In this way, the seismic information collected by geophones can be used to produce seismic reflection signals which can be processed to form images of the subsurface.
  • a vibrator It has become common in many cases to use, as the source of propagating elastic waves, a hydraulically-operated vibratory source more simply referred to as a vibrator.
  • energy sources for vibrators like electromechanical or pure electric. All of these systems typically generate vibrations or shock waves by using a reaction mass member that is actuated by a hydraulic or electric system and electrically controlled by a servo valve.
  • a vibrator comprises a double ended piston rigidly affixed to a coaxial piston rod. The piston is located in reciprocating relationship in a cylinder formed within a heavy reaction mass.
  • Means are included for alternately introducing hydraulic fluid under high pressure to opposite ends of the cylinder or for an electric coil and magnet type assembly to impart a reciprocating motion to the piston relative to the reaction mass.
  • the piston rod extending from the reaction mass is rigidly coupled to a baseplate, which is maintained in intimate contact with ground surface. Since the inertia of the reaction mass tends to resist displacement of the reaction mass relative to the earth, the motion of the piston is coupled through the piston rod and baseplate to impart vibratory seismic energy in the earth.
  • vibrators are transported by carrier vehicle, and it is also known to prevent decoupling of the baseplate from the ground by applying a portion of the carrier vehicle's weight to the baseplate during operation.
  • the weight of the carrier vehicle is frequently applied to the baseplate through one or more spring and stilt members, each having a large compliance, with the result that a static bias force is imposed on the baseplate, while the dynamic forces of the baseplate are decoupled from the carrier vehicle itself.
  • the hydraulic system forces the reaction mass to reciprocate vertically, at the desired vibration frequency, through a short vertical stroke.
  • This type of vibrational seismic exploration system typically uses a quasi-sinusoidal reference signal, or so-called pilot signal, of continuously varying frequency, selected band width, and selected duration to control the introduction of seismic waves into the earth.
  • the pilot signal is converted into a mechanical vibration in a land vibrator having a baseplate which is coupled to the earth.
  • the land vibrator is typically mounted on a carrier vehicle, which provides locomotion.
  • the baseplate is contacted with the earth's surface and the weight of the carrier vehicle is applied to the baseplate.
  • a servo-hydraulic piston connected to the baseplate is then excited by the pilot signal, causing vibration of the baseplate against the earth.
  • a significant problem with conventional systems employing a vibrating baseplate to impart seismic waves into the earth is that the actual motion of the baseplate, and thus the actual seismic energy imparted to the earth, is different from the ideal motion represented by the pilot signal.
  • This difference can be caused by a variety of factors, including (1) harmonic distortion or "ringing" of the baseplate, (2) decoupling of the baseplate from the earth's surface commonly referred to as bouncing or "pogo-sticking," and (3) flexure of the baseplate.
  • the differences between the pilot signal and the actual baseplate motion are problematic because, in the past, the pilot signal was used to pulse-compress the reflected seismic signal either through correlation or inversion.
  • the pulse-compressed reflected seismic signal that is produced by correlation or more modernly by inversion is inaccurate.
  • the present invention relates generally to methods and systems for inducing seismic vibrations into an elastic medium. More particularly, but not by way of limitation, embodiments of the present invention include methods and systems for inducing seismic vibrations into subterranean formations utilizing improved seismic baseplates.
  • An example of a method for inducing seismic energy waves in a subterranean formation comprises the steps of: providing a seismic transducer apparatus comprising a frame, a baseplate attached to the frame, the baseplate having a flat lower surface for engagement of a ground surface, the baseplate having a circumference; a reaction mass supported by the frame, and a driver configured to actuate the reaction mass in a reciprocating motion; wherein the circumference of the baseplate is in the form of a polygon, wherein the polygon comprises at least five sides; engaging the ground surface with the baseplate; actuating the reaction mass via the driver in a reciprocating motion; allowing vibratory energy to be imparted to the baseplate so as to propagate seismic energy waves in the subterranean formation; allowing the seismic energy waves to propagate through the subterranean formation so as to produce reflected and refracted seismic energy waves; and detecting one or more of the reflected and refracted seismic energy waves.
  • An example of a seismic transducer apparatus for inducing energy waves in an elastic medium comprises: a frame; a baseplate attached to the frame, the baseplate having a flat lower surface for engagement of a surface of an elastic medium, the flat lower surface having a perimeter, wherein the perimeter is in the form of a polygon, wherein the polygon comprises at least five sides; a reaction mass supported by the frame; and a driver configured to actuate the reaction mass in a reciprocating motion so as to impart vibratory energy to the baseplate.
  • An example of a seismic vibrator apparatus comprises: a frame; a baseplate attached to the frame, the baseplate having a lower surface for engagement of a ground surface, the lower surface having a perimeter, wherein the perimeter is in the form of a polygon, wherein the polygon comprises at least five sides; wherein the base plate is comprised of an upper plate, a lower plate, and one or more members that extend from the upper plate to the lower plate so as to couple the upper plate to the lower plate; a reaction mass supported by the frame; and a driver configured to actuate the reaction mass in a reciprocating motion so as to impart vibratory energy to the baseplate.
  • Figure 1 illustrates a side view of one example of a seismic exploration system in accordance with one embodiment of the present invention.
  • Figure 2 illustrates a side view of one example of a seismic transducer in accordance with one embodiment of the present invention.
  • Figure 3A illustrates a top view of an octagonal baseplate in accordance with one embodiment of the present invention.
  • Figure 3B illustrates a side view of an octagonal baseplate in accordance with one embodiment of the present invention.
  • Figure 4A illustrates a top view of a hexagonal baseplate in accordance with one embodiment of the present invention.
  • Figure 4B illustrates a side view of a hexagonal baseplate in accordance with one embodiment of the present invention.
  • Figure 5 illustrates a side view of a baseplate having a plurality of truss members in accordance with one embodiment of the present invention.
  • the present invention relates generally to methods and systems for inducing seismic vibrations into an elastic medium. More particularly, but not by way of limitation, embodiments of the present invention include methods and systems for inducing seismic vibrations into subterranean formations utilizing improved seismic baseplates.
  • seismic transducers in accordance with the present invention comprise a frame, a reaction mass supported by the frame, a driver, and a baseplate attached to the frame.
  • the driver actuates the reaction mass in a reciprocating motion, imparting a vibratory energy to the baseplate.
  • the baseplate is engaged with a ground surface during operation, the vibratory energy of the baseplate is imparted directly to the ground surface so as to propagate seismic waves into the subterranean formation.
  • the seismic waves are then reflected and refracted by the subsurface strata and geological features of the subterranean formation.
  • the reflected and refracted seismic waves may then be detected by a plurality of seismic detectors.
  • the detected seismic data is then interpreted to reveal seismic information representative of the surveyed subsea region of the earth.
  • baseplates of the present invention may include certain enhancements such as having a perimeter in the shape of a polygon, such as, for example, an octagon.
  • Advantages of such baseplate enhancements include, but are not limited to, a reduction of baseplate harmonics or ringing, enhanced baseplate strength so as to reduce baseplate fatigue, subsequent fracture, or failure, a reduction of baseplate flexure, and a consequent reduction of baseplate weight resulting in a baseplate more responsive to actuation,
  • FIG. 1 illustrates a side view of one example of a seismic exploration system in accordance with one embodiment of the present invention.
  • a pilot signal is generated in recorder/processor carrier vehicle 111 and sent by radio wave link 112 to a land vibrator 120.
  • Land vibrator 120 converts the pilot signal into mechanical motion that vibrates baseplate 130.
  • Baseplate 130 contacts ground surface 180 of the earth and is coupled to ground surface 180 by the weight of carrier vehicle 110.
  • Baseplate 130 induces seismic waves 162 into subsurface 182 of the earth. Induced seismic wave 162 travels downward through subsurface 182 and is altered (i.e., refracted and/or reflected) by subsurface strata 183.
  • Altered seismic waves 164 travels from subsurface strata 183 upward through subsurface 182 to surface 180.
  • Seismic receivers 185 such as geophones, located on surface 180, are generally spaced apart from each other and from land vibrator 120. Seismic receivers 185 measure altered seismic waves 164 at surface 180 and transmit an altered seismic signal indicating altered seismic wave 28 across geophone lines 184 to recorder/processor carrier vehicle 110. This communication may be accomplished via wires conventionally, or with autonomous recorders where the data is later collected and transcribed to the recording media. A baseplate signal is transmitted from land vibrator 120 via radio wave link 112 to recorder/processor carrier vehicle 110 for processing. In this way, seismic survey data is collected and interpreted so as to reveal the nature and the geology of subterranean formation 182.
  • FIG. 2 illustrates a side view of one example of a seismic transducer in accordance with one embodiment of the present invention.
  • Seismic transducer apparatus 200 utilizes a reciprocating motion of reaction mass 225 to impart vibratory energy to baseplate 230.
  • frame 222 supports and is rigidly connected to piston rod 223 and baseplate 230.
  • Driver 224 pumps or otherwise supplies hydraulic fluid to hydraulic cylinder 227 through ports 225. In this way, driver 224 actuates reaction mass 226 about piston rod 223.
  • reaction mass 226 is supported by frame 222, this reciprocating motion is transmitted to baseplate 230 via the inertia of reaction mass 226.
  • baseplate 230 corresponding to the motion of reaction mass 226.
  • Baseplate 230 then transmits the vibratory energy to a ground surface (such as ground surface 180 depicted in Figure 1) via flat lower surface 233.
  • baseplate 230 comprises angled edges along the perimeter of baseplate 230. These angled edges, e.g. edges that are deviated from the vertical or non-perpendicular) aid in the clearing of mud or other soil or sludge that may accumulate along the perimeter of baseplate 230.
  • baseplate 230 comprises one or more improvements for producing an enhanced baseplate.
  • Figure 3A illustrates a top view of an octagonal baseplate in accordance with one embodiment of the present invention.
  • perimeter 333 of baseplate 330 forms the shape of a polygon, having n sides, where n may be any integer greater than 4.
  • perimeter 333 of baseplate 330 is in the shape of an octagon.
  • baseplate 330 depicted in Figure 3A is shown here as an equilateral polygon, it is recognized that perimeter 333 of baseplate 330 may form an irregular polygon.
  • the octagonal shape of perimeter 333 of baseplate 330 reduces the flexure problems that are experienced particularly by circular baseplates, which is caused by the nature of their construction. This reduction in flexure of baseplate 330 reduces harmonics and ringing of baseplate 330. Likewise, the octagonal shape also dramatically reduces the fatigue and failure rate of baseplate 330. Additionally, the octagonal shape of baseplate 330 reduces the weight of baseplate 330 relative to a conventional rectangular or circular baseplate, which results in a more responsive baseplate.
  • FIG. 3B illustrates a side view of an octagonal baseplate in accordance with one embodiment of the present invention.
  • Baseplate 330 comprises upper plate 331, lower plate 332, and a plurality of walls 334. Walls 334 extend between upper plate 331 and lower plate 332 so as to join or otherwise couple upper plate 331 to lower plate 332.
  • upper plate 331, lower plate 332, and a plurality of walls 334 is formed as one integral unit, such as, being cast from a one or more dies or molds.
  • Forming baseplate 330 from a solid steel baseplate structure would impose a severe weight penalty on the vibrating mechanism.
  • baseplate 330 may be maintained within acceptable weight limitations and yet be capable of withstanding the large forces generated by a seismic transducer.
  • Figure 4A illustrates a top view of a hexagonal baseplate in accordance with one embodiment of the present invention.
  • perimeter 433 of baseplate 430 is in the shape of a hexagon.
  • this polygonal shape offers one or more of the aforementioned advantages over circular and rectangular baseplates.
  • the polygonal shape provides enhanced coupling of the baseplate with any organic surface layer that may be present on the ground (e.g. grass or other foliage).
  • the reduced surface area of the polygonal shape concentrates the force applied into a more limited surface area and offers enhanced compression of the organic layer to achieve the enhanced coupling of the baseplate and the ground surface.
  • baseplate 430 allows seismic transducers that incorporate baseplate 430 to operate at higher seismic frequencies ranges without producing substantial signal distortion or noise.
  • seismic transducers of the present invention operate at frequency ranges extending into the higher seismic frequency range of at least about 80 cycles per second, at least about 150 cycles per second, and/or at least about 250 cycles per second.
  • Figure 4B illustrates a side view of a hexagonal baseplate in accordance with one embodiment of the present invention.
  • upper plate 431 and lower plate 432 are in the shape of a polygon and more specifically, take the shape of a hexagon. It is recognized that the perimeter of upper plate 431 and/or lower plate 432 may take the form of a polygonal shape. In certain embodiments, only lower plate 432 takes the form of a polygon.
  • baseplate 430 is constructed from a plurality of parallel steel I- beams.
  • Each I-beam is formed from an upper flange 443, a lower flange 445, and a web 447 that joins upper flange 443 to lower flange 445.
  • the longitudinal axes of the I-beams are located parallel to one another and adjacent I-beams are oriented so the edges of their upper and lower flanges are abutting (the webs of the I-beams lie in vertical planes).
  • the I-beam flanges may be welded together so as to provide a unitary structure, which may be further reinforced by optional upper and lower reinforcing plates 431 and 432. It will be appreciated that this type of structure provides great resistance to stress exerted along the longitudinal axis of the I-beams, yet would be substantially lighter than a solid cast plate.
  • FIG. 5 illustrates a side view of a baseplate having a plurality of truss members in accordance with one embodiment of the present invention.
  • baseplate 530 is depicted comprising upper plate 531, lower plate 532, and a plurality of truss members 536.
  • Truss members 536 extend between upper plate 531 and lower plate 532 so as to join or otherwise couple upper plate 531 to lower plate 532.
  • upper plate 531 or lower plate 532 may be formed in the shape of the aforementioned polygons.
  • both upper plate 531 and lower plate 532 may be formed in the shape of the aforementioned polygons.

Abstract

L'invention concerne des procédés et des systèmes destinés à induire des ondes d'énergie sismique dans une formation souterraine. Plus précisément, l'invention concerne des transducteurs sismiques incorporant des semelles sismiques améliorées. Dans certains modes de réalisation, les semelles comportent certaines améliorations comme le fait de présenter un périmètre en forme de polygone, par exemple un hexagone ou un octogone. Dans d'autres modes de réalisation, le périmètre de la semelle peut prendre la forme d'un polygone à n côtés, n étant un entier quelconque supérieur à 4. Entre autres avantages de telles améliorations des semelles, on peut citer de façon non limitative une réduction des harmoniques de semelle ou tintement, une résistance renforcée de la semelle qui a pour effet de réduire la fatigue ou les ruptures de la semelle, une réduction de la flexion de la semelle et une réduction résultante du poids de la semelle, qui donne une semelle plus réactive. Ces avantages se traduisent finalement par des relevés sismiques améliorés, une plus haute résolution des formations explorées et des relevés atteignant des profondeurs plus importantes.
PCT/US2011/025302 2010-02-18 2011-02-17 Transducteurs sismiques dotés de semelles polygonales améliorées et procédés pour leur utilisation WO2011103331A1 (fr)

Applications Claiming Priority (12)

Application Number Priority Date Filing Date Title
US30569710P 2010-02-18 2010-02-18
US30569210P 2010-02-18 2010-02-18
US30568910P 2010-02-18 2010-02-18
US61/305,697 2010-02-18
US61/305,692 2010-02-18
US61/305,689 2010-02-18
US13/027,982 US8167082B2 (en) 2010-02-18 2011-02-15 Seismic transducers having improved polygonal baseplates and methods of use
US13/027,982 2011-02-15
US13/028,029 US8261875B2 (en) 2010-02-18 2011-02-15 Seismic transducers and baseplates having external dampeners and methods of use
US13/028,029 2011-02-15
US13/028,007 2011-02-15
US13/028,007 US8342288B2 (en) 2010-02-18 2011-02-15 Seismic transducers having reduced surface area baseplates and methods of use

Publications (1)

Publication Number Publication Date
WO2011103331A1 true WO2011103331A1 (fr) 2011-08-25

Family

ID=44483306

Family Applications (3)

Application Number Title Priority Date Filing Date
PCT/US2011/025302 WO2011103331A1 (fr) 2010-02-18 2011-02-17 Transducteurs sismiques dotés de semelles polygonales améliorées et procédés pour leur utilisation
PCT/US2011/025304 WO2011103333A1 (fr) 2010-02-18 2011-02-17 Transducteurs sismiques dotés de semelles d'aire surfacique réduite et procédés pour leur utilisation
PCT/US2011/025307 WO2011103336A1 (fr) 2010-02-18 2011-02-17 Transducteurs et semelles sismiques dotés d'amortisseurs externes et procédés pour leur utilisation

Family Applications After (2)

Application Number Title Priority Date Filing Date
PCT/US2011/025304 WO2011103333A1 (fr) 2010-02-18 2011-02-17 Transducteurs sismiques dotés de semelles d'aire surfacique réduite et procédés pour leur utilisation
PCT/US2011/025307 WO2011103336A1 (fr) 2010-02-18 2011-02-17 Transducteurs et semelles sismiques dotés d'amortisseurs externes et procédés pour leur utilisation

Country Status (1)

Country Link
WO (3) WO2011103331A1 (fr)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3427706A (en) * 1964-11-13 1969-02-18 Douglas Aircraft Co Inc Sandwich structures and method
US4406345A (en) * 1979-08-08 1983-09-27 Conoco Inc. Seismic transducer baseplate and housing assembly
US4676337A (en) * 1985-09-03 1987-06-30 Western Geophysical Company Of America Seismic vibrator baseplate
US4875544A (en) * 1989-02-02 1989-10-24 Atlantic Richfield Company Transducer for inducing seismic signals into an elastic medium
US20020149998A1 (en) * 2001-03-07 2002-10-17 Phillips Petroleum Company Method and apparatus for measuring seismic energy imparted to the earth

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2684352A (en) * 1953-10-12 1954-07-20 Us Rubber Co High impact strength thermoplastic composition containing polyvinyl acetal resin and butadiene elastomer
US4026383A (en) * 1974-11-04 1977-05-31 Texas Instruments Incorporated Gyroscopic vibrator
US4298086A (en) * 1979-10-09 1981-11-03 Atlantic Richfield Company Coupling means for horizontal vibrator
US4712641A (en) * 1984-03-19 1987-12-15 Bolt Technology Corporation Method and system for generating shear waves and compression waves in the earth for seismic surveying
GB8414907D0 (en) * 1984-06-12 1984-07-18 Shell Int Research Multisensor ground-force measuring means
US5292811A (en) * 1988-11-21 1994-03-08 Mitsui Petrochemical Industries, Ltd. Process for preparing thermoplastic elastomers
US6065562A (en) * 1998-07-27 2000-05-23 Industrial Vehicles International, Inc. System for imparting compressional and shear waves into the earth
FR2818754B1 (fr) * 2000-12-21 2004-06-18 Inst Francais Du Petrole Dispositif pour engendrer des ondes elastiques focalisees dans un milieu materiel tel que le sous-sol, et methode pour sa mise en oeuvre

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3427706A (en) * 1964-11-13 1969-02-18 Douglas Aircraft Co Inc Sandwich structures and method
US4406345A (en) * 1979-08-08 1983-09-27 Conoco Inc. Seismic transducer baseplate and housing assembly
US4676337A (en) * 1985-09-03 1987-06-30 Western Geophysical Company Of America Seismic vibrator baseplate
US4875544A (en) * 1989-02-02 1989-10-24 Atlantic Richfield Company Transducer for inducing seismic signals into an elastic medium
US20020149998A1 (en) * 2001-03-07 2002-10-17 Phillips Petroleum Company Method and apparatus for measuring seismic energy imparted to the earth

Also Published As

Publication number Publication date
WO2011103336A1 (fr) 2011-08-25
WO2011103333A1 (fr) 2011-08-25

Similar Documents

Publication Publication Date Title
US8167082B2 (en) Seismic transducers having improved polygonal baseplates and methods of use
EP1999490B1 (fr) Appareil et procédé pour générer un signal de source sismique
US7881158B2 (en) Seismic vibrator having multiple resonant frequencies in the seismic frequency band using multiple spring and mass arrangements to reduce required reactive mass
US7551518B1 (en) Driving means for acoustic marine vibrator
US6179084B1 (en) Underground acoustic wave transmitter, receiver, transmitting/receiving method, and underground exploration using this
US5080189A (en) Electro-hydraulic dipole vibrator
EP2363734B1 (fr) Transducteurs sismiques dotés de plaques de base de zone de surface réduite
EP2365357B1 (fr) Transducteurs sismiques dotés de plaques de base à surface réduite
US20110272206A1 (en) Matrix ground force measurement of seismic transducers and methods of use
KR101120485B1 (ko) 탄성파 탐사용 횡파 발생장치
WO2011103331A1 (fr) Transducteurs sismiques dotés de semelles polygonales améliorées et procédés pour leur utilisation
EP2365358B1 (fr) Transducteurs sismiques dotés de plaques à amortisseurs externes
CA2985482C (fr) Vibrateur a actionneurs multiples
EP3295217B1 (fr) Vibrateur à actionneurs multiples
US8689930B2 (en) Seismic vibrator having airwave suppression

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 11745252

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 11745252

Country of ref document: EP

Kind code of ref document: A1