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Study Of Structural Characteristics And Oil-gas Perspective In Boli-Jixi Basin

Posted on:2010-07-27Degree:DoctorType:Dissertation
Country:ChinaCandidate:Y X LiuFull Text:PDF
GTID:1100360272496152Subject:Solid Earth Physics
Abstract/Summary:PDF Full Text Request
Boli basin and Jixi basin located at our country Daqing Oil field prospecting region periphery, have the superiority region superiority and the exploration prospect. Strengthens to two basin geological data research, is advantageous in Daqing periphery prospecting region oil gas reserves investigation thorough expansion. Had the geologist to conduct the petroleum geology characteristic research to these two basins, but is related the geophysics material is more limited. This article studies the Boli basin and the Jixi basin gravitational field characteristic through the regional gravity data, and divides the faulted structure using the gravity reduction data computation basis depth, the union earth electromagnetism depth sounding material carries on the geophysics and the geologic interpretation. Is for the purpose of verifying two basins the basis nature, the basin boundary, the break position and the reciprocity, for geological duties and so on optimal advantageous exploration strategy target area provides the geophysics field the evidence. The research process including the method and the geologic interpretation two aspects, mainly studies the content to be as follows.1.In recent years, the wavelet analysis method became in the signal processing when -frequency analysis new method, but was few in number the first generation of wavelet and the promotion wavelet application in the potential field data denoising aspect's literature. Because includes the noise jamming frequently in the gravity actual signal, only then the rejection noise can the signal useful information performance. This article expected that applies the first generation of wavelet and the promotion wavelet carries on processing to the gravity measured data, thus enhances the actual data the application effect.In the article has related in detail the wavelet analysis correlation theories, discussed the Fourier transformation and the wavelet transformation time - frequency analysis characteristic and wavelet promotion method own superiority. In the numerous wavelet primary functions, the orthogonal wavelet decomposition has the auto-adapted time - frequency localization function, the biorthogonal wavelet has the good restructuring signal function, the promotion wavelet can, in does not consume the memory under the condition to accelerate the wavelet transformation, is the wavelet transformation highly effective algorithm. In view of the fact that the above several kind of wavelet primary function's characteristic, this article selects the orthogonal db4 wavelet and the biorthogonal bior3.5 wavelet carries on the letter chirp separation to the gravity data.2.Because the gravity measured data may the packet of energy include the sudden change signal, therefore divides into the gravity anomaly model the steady signal and the non-steady signal two parts, take this analysis wavelet primary function regarding the different signal's adaptation degree, and using the signal-to-noise ratio, the magnitude of error, the standard deviation and the image similarity does as the denoising effect measurable.Discovered through the model experiment that regarding the steady signal, the Fourier transformation, based on Brige-Massart the strategy determination threshold value's db4 wavelet, the bior3.5 wavelet and is biggest based on the promotion algorithm soft threshold value's bior3.5 wavelet to the signal-to-noise ratio promotion scope, their reconstruction effect is similar, is quite ideal.Regarding non-steady signal, but the packet of energy includes the sudden change information, some high frequency exceptionally often with the noise signal dopes in together. The model experiment indicated that the traditional Fourier transformation method cannot satisfy the non-steady signal the filter processing request, because this method cannot differentiate by the noise production high-frequency unit and the high-frequency unit which produces by the shallow layer geologic body. Because can not be able to attend to one thing without losing track of another thing purely to the frequency range filter, outside bandpass frequency spectrum is not differentiated filters. But in the wavelet transformation the noise signal and the unusual signal high frequency have the different threshold value level, may the selective discrimination not use the origin according to this characteristic high frequency exceptionally. The orthogonal wavelet and the biorthogonal wavelet have the very strong separating capacity regarding the noise signal and the high frequency signal, may restructure in the elimination noise foundation high frequency exceptionally. Is best based on the promotion algorithm soft threshold value's biorthogonal wavelet bior3.5 restructuring effect, may raise the counting yield during separation letter chirp.3.Through to the wavelet analysis in filter's research, used based on the promotion algorithm soft threshold value bior3.5 wavelet has processed Boli and the Jixi basin observed gravity data. When carries on the computation using the Euler deconvolution, if is not good using the letter chirp separation effect, the inversion result will receive the noise jamming to produce many separate spots, will create some break position insufficient centralism, the resolution is bad, will thus affect to the break position division. But after using the wavelet analysis in method's promotion wavelet bior3.5 carries on the denoising, some do not restrain the inversion point position obtains the elimination, enables the break division the accuracy to have the enhancement.4.0n the study of Boli basin and Jixi basin, uses the region Bouguer gravity anomaly, the derivative chart and in the upward continuation chart division research area faulted structure, M discontinuity's depth and carries on the analysis contact surface fluctuation shape using Park the law computation basin. Has carried on the division to the basin deposition scope, has selected the basin boundary, and has analyzed the gravitational field change rule. Synthesis massive geology and geophysics material, analysis peripheral faulted structure to basin influence. The analysis result indicated that Boli and the Jixi two basins have the close gravitational field characteristic, and structurally receives the peripheral deep big break the influence, once some scholars thought that Boli and Jixi have the same thing source, is the unified prototype basin has carried on the inference to the eastern basin. Therefore looked from the gravity angle that Boli and the Jixi basin should for the unified prototype basin, this regarding analyze both's oil gas potential to have the important geological significance.5.0n the study of the two basins important boundary structure belt and controls the trough break the geophysics field characteristic. Carries on the restraint using the neighboring area Hulin basin's three seismic cross-section to the gravity basis inversion result, based on this calculates three gravity reductions using the linear method of inversion the basis depth, divides the section plane using the Euler deconvolution computation's result and the electrical method material union the faulted structure. And the DB2 section plane located at the Boli basin east end, uses this section plane gravity data recognition Boli basin the south reason and north the reason boundary breaks each two, these breaks are affecting the Boli basin deposition scope and the conformation. The earth electromagnetism depth sounding material demonstrated that after entering the Boli basin, the electric properties have the obvious change, from this may distinguish the basin boundary break similarly. Discovered in the parsing process that the sincere dense break presents group of fault zones in the gravity and in the earth electromagnetism depth sounding material the mop shape. The DB3 section plane passes through two basins, located at the Boli basin middle. May distinguish Boli and the Jixi basin boundary break using the gravity data, has the change similarly in this position electric properties. The DB4 section plane located at the Boli basin's west end, distinguishes the Boli basin using the gravity and the electrical method material the west reason boundary break. The analysis thought that - Yitong breaks the similar performance located at Boli west of the basin is the same group of fault zone shape.6. Based on the gravitational and magnetotelluric data, we divided structural divisions in the sections. We also divided setion DB2 of Danbizhen, Dadingshan uplift, Dunmi subsidence, Mishan uplift, Boli basin, Fenshuigang uplift, Baoqing subsidence.The deepest depth of the gravity floor is 3 km.Then divided setion DB3 of Suiyang uplift, Dunmi subsidence, Muling uplift, Jixi Basin, Nadanhada uplift, Qitaihe uplift, Boli Basin, Qitaihe uplift, Beixing depression and Qixingzhen uplift. The deepest depth of the gravity floor is 5 km in Dunmi subsidence. We also divided setion DB4 of Xiaoxinganling uplift, Tangyuan subsidence, Yilan subsidence, Guokuishan uplift and Boli Basin. The deepest depth of the gravity floor is 2km in Tangyuan subsidence. Studyed the gravitational and magnetotelluric data, we analysics the area which have differed density and resistivity. We made an emphasis study the gravity anomaly, gravity floor and the variation of resistivity.7. Because the influence oil gas production, the accumulation, the storage and the escape factor is numerous, the oil gas analysis included all geological condition and the geological process nearly. Therefore through the preamble analysis, according to the collection geophysics and the geological data, has inferred Boli and the Jixi basin and the neighboring area oil gas prospect area from the gravity and the electrical angle.The first-level oil gas prospect area located at Boli basin north of treasure clear hollow (located at the DB2 section plane north most part). Analyzes from the structure, the gravity recognition's two breaks in 12 kilometers depths gather, break cutting is together deep, in the electric properties also distinguishes a break. In present's exploration, should pay attention to this break emphatically to this area oil gas influential role. The break has the possibility to destroy the oil gas accumulation, the structure causes the oil gas escape stave; Also has the possibility for the oil-gas migration constitution channel. Analyzes from the electric properties, lower part this depression's low resistivity extends the scope to be big, the electronic resistivity is extremely low, the magnitude only then severalΩ·m, in this crystallizing field's low stop-band possibly seeks for the oil gas Tibet's advantageous region. The second-level prospect area breaks located at Tangyuan falls the interior (the DB4 section plane Yilan County position). From the structure analyzes, the gravity distinguishes a Yilan - Yitong master fracture in this area, extends to 10km about. The electric properties demonstrate this area existence Yilan-Yitong fault zone. If this position existence transformation oil gas's condition, these big breaks should be possible to provide the good transportation channel, but breaks to the oil gas destructiveness also exists. Analyzes from the electric properties, should break falls internal has had the big area low density material, possibly was follows breaks falls in the drop process, middle had the partial magma invasion, creates the nowadays top and bottom low, the middle electronic resistivity high structure framework. Level mop width approximately 5km, in this part of low resistivity flank existence obvious electrical difference. This region surface layer was the low resistivity, the lower level was still a low resistivity, inferred it is the advantageous oil gas field, and suggested that carried on next step sifts the work.As the small oil field prospect area, may develop to further Boli and the Jixi basin sifts the work. Periphery looks over in three section planes the Boli basin resistivity distribution situation, the Boli basin interior electronic resistivity whole is lower than constructs the belt, anti- follows the few low resistivity distribution primarily basically by, the shallow layer often has the small area low resistivity in the partial distribution, has certain ethylene prospect, but the section plane material demonstration low resistivity area scale is not big. DB3 (the Suifen River - Big Dipper town) in the section plane Jixi basin scope width about 45km, between the section plane 149-174th spot, is middle the Jixi basin secondary structure. Among the gravity basis has blister, the deepest place is 2 km. The electronic resistivity reflects lower part the Jixi basin is extends the deep conductive bed downward. Two basins both belong to the fault comparison growth area, creates Boli area region Cheng Cengxing the difference. Has the possibility to form the fault seal structure, from this produces the fault block bulge or drops the area, has the possibility to form the good oil storage place. Speaking of these two basin's geological situation possibly forms the middle and small scale the oil-gas field.In summary, this article research has made certain progress, has studied each kind of wavelet base and the promotion wavelet in the method to the gravity data filter effect, has studied the wavelet base and the promotion wavelet with emphasis in processing steady and in the non-steady unusual signal characteristic, thus enhanced the gravity data inversion accuracy. In the data processing and the explanation aspect, have studied the Boli basin and the Jixi basin gravitational field essential feature, gained with the basin oil gas prospect related geophysics field evidence, has provided the beneficial supplement for the foundation geological data.
Keywords/Search Tags:Boli-Jixi Basin, Structural Characteristics, Oil-gas perspective
PDF Full Text Request
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