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The Kirchhoff Q PSDM technique is studied in this paper in order to compensate the amplitude and correct the distortion of phase due to seismic attenuation in the earth, during the seismic waves traveling through the earth, especially through the the gas cloud region, to improve the resolution of the imaging results, and to satisfy the requirements of industrial production. In order to improve the calculation efficiency of the QPSDM, a time domain interpolation strategy is also proposed. This strategy avoids the compensation in frequency doamin at each imaging point, which is time-consuming. The computation efficiency of Q migration has been greatly improved with our method, making the Kirchhoff QPSDM able to meet the needs of industrial production. By analyzing the sources of the high frequency noise, the time-variant gain-limits are used to suppress the high frequency noise in the compensation procedure. The numerical results show that the compensation method using the time-variant gain-limits can effectively compensate the energy of the severe attenuation region while suppressing the high-frequency noise. Finally, we test the QPSDM approach on synthetic data and field data. These examples demonstratethat the QPSDM approach could produce higer resolution images with imporoved amplitude and correct phase compared to the convetional PSDM. The Kirchhoff QPSDM technology realized in this paper has produced desirable seismic images while it is applied in many exploration areas such as Dagang, Daqing, Malaysia, Nanhai, etc.
Liu, Wei (BGP, CNPC, Chengdu University of technology) | He, Zhenhua (Chengdu University of technology) | Cao, Junxing (Chengdu University of technology) | Zhang, Jianjun (BGP, CNPC) | Xu, Gang (BGP, CNPC) | Wan, Xiaoping (BGP, CNPC) | Yu, Gang (BGP, CNPC)
Shale play, as one kind of non-conventional natural gas resource, has become the focus of domestic and overseas research in recent years. shale is pertained to be a reservoir with an ultralow porosity and permeability, its occurrence mode, accumulation pattern of natural gas, as well as development model are remarkably different conventional oil gas reservoirs, its development must be implemented by some special technique, e.g. horizontal drilling, drilling geologic steering, hydraulic fracturing, microseismic monitor, etc. Research shows, shale gas production depends on two factors, one is geological sweet spot factor, e.g. Total organic carbon, brittleness, core fluid pressure, micro-fractures, high quality shale thickness etc., the other is engineer technique factors, e.g. horizontal drilling, drilling geologic steering, hydraulic fracturing, microseismic monitor, fracturing schemes, etc. Single factor, sweet spots or engineering technique factor often not guarantee shale gas highly production, only when the most optimal combination of both, can achieve shale gas production maximization. How to integrate sweet spots and engineering technique to guide shale gas exploration and development? This is a serious question. This question involves to many fields, including geology and engineer sweet spots, horizontal well location deployment, drilling geologic steering, pre-fracturing warning and design, hydraulic fracturing design real-time adjustment, microseismic monitoring, etc., sweet spots results runs through the entire shale exploration and development. In this article, we will pay more attention to demonstrate that how to adjust the fracturing scheme and optimize the reservoir stimulation in real time by integrated geological sweet Spot and microseismic monitor.
A heavy oil field is developed with the Steam Assisted Gravity Drainage (SAGD). Since the start of oil production, the oil production amount of the studied reservoir has been lower than that of the surrounding oil fields. The development of the steam chambers are relatively poor, and the spatial distribution of the steam chambers is not clear. In order to describe the shape of the steam chambers accurately, a novel method of monitoring the steam chambers is proposed by using broadband, high-density seismic data and dynamic production data. Broadband, high-density seismic data are acquired. Firstly, seismic horizons are well interpreted, and multiple seismic attributes are analyzed in combination with well data to understand the seismic response of the steam chambers. Then, several seismic inversion methods are tried to obtain high-resolution impedance, and they are compared with each other to find optimal inversion result for steam chamber prediction. Finally, the shape of the steam chambers are delineated with seismic attributes, inverted impedance, production data, and temperature logs of observation wells. The predicted steam chamber has good agreement with the temperature logs of observation wells. The result shows that the appearance of steam chambers has an obvious impact on seismic signals, and broadband, high-density seismic data make great contributions to the description of the steam chambers. The proposed method reduces the uncertainty in steam chamber prediction with single data source, and is applicable to other oilfields using steam injection.
Xin, C. (BGP.CNPC) | Zhaowei, L. (CNODC,CNPC) | Zhaofeng, W. (PKKR.CNPC) | Wenyuan, T. (BGP, CNPC) | Yaliang, X. (BGP, CNPC) | Yanjing, L. (BGP, CNPC) | Xiaodong, W. (BGP, CNPC) | Hongmei, W. (BGP, CNPC) | Yu, J. (University of Southern California) | Xiaohuan, Y. (BGP, CNPC)
In order to improve the accuracy of reservoir prediction results, the conventional method usually include seismic inversion, and wei. Due to the limitation of the vertical resolution of seismic data, it is hard to identify the thin reservoir by seismic attributes directly. In order to improve the prediction accuracy of reservoir, this paper show a new reservoir characterization technique based on geological seismic conditioning. The new method mainly includes five steps. The first step is sedimentary facies classification based on the geological seismic analysis, such as core data, thin section analysis, FMI logging, NMR logging and conventional logging. The second step is modern sedimentary model optimization and forward modelling. In order to establish a reasonable sedimentary facies model, a similar barrier island modern sedimentary model was chose. To understand the geological significance of seismic data, two different dominant frequency were designed for forward modelling based on the sedimentary facies model and petrophysical analysis. The third step is seismic conditioning under the guide of sedimentary facies model forward modelling. The next step is seismic constraint stochastic inversion, and the last step is reservoir characterization and new well confirm. The application of this method in A oilfield shows that the techniques not only improved the identification ability of the reprocessing seismic data, but also improved the prediction accuracy of the reservoir characterization results. This new reservoir characterization technique can integrated multidisplinary information, such as modern sedimentary model, well data and seismic data, to establish a reasonable sedimentary model, to enhance the resolution of seismic data by conditioning, and get an reasonable reservoir characterization results based on the seismic inversion.
Compared with conventional imaging methods, Leastsquares migration (LSM) can produce images with improved resolution and reduced migration artifacts. However, LSM has been mainly restricted to the imaging of acoustic wavefields. In this abstract, we use Gaussian beams as wave propagator to formulate a least-squares migration scheme for elastic waves of isotropic media. With this method, not only can we obtain better illuminated multi-wave images with higher resolution, but also we can achieve a good balance between computational cost and imaging accuracy, which are both important requirements for iterative LSM methods. A synthetic Marmousi 2 dataset is used to demonstrate the validity and effectiveness of our proposed method.
Presentation Date: Tuesday, October 16, 2018
Start Time: 1:50:00 PM
Location: 207A (Anaheim Convention Center)
Presentation Type: Oral
Due to the restriction of channel capacity (the maximum active channels outside the host and the normal data recovery capacity) and operation convenience, the traditional wire seismic recorder is no longer qualified in respect of HSE requirements and efficient and fast operation. Especially in areas with complex terrain, the difficulty of layout is greatly increasing. In this situation, the memory type wireless node seismic recorder emerges. With independent acquisition station, this recorder removes the time-consuming array construction and check procedures of traditional wire seismic recorder. It does not involve data communication between the acquisition station and the recorder, so the online channels can be extended randomly. It is often used with two instruments to fully utilize the advantages of the instrument. Therefore, joint construction of nodes and wired instruments is applied in more and more project. This paper introduces the successful implementation of joint application of hawk nodes and wired instruments in western China, analyzes the data separating in micro seismic acquisition, the separation of data recorded by hawk nodes and the merging of wired and node data.
Presentation Date: Tuesday, October 16, 2018
Start Time: 9:20:00 AM
Location: Poster Station 11
Presentation Type: Poster
Multicomponent joint inversion is an important technique for reservoir prediction using PP and PS seismic data. The addition of PS data is helpful to solve the problem of multiplicity and increase the precision of reservoir prediction. Based on 3D multicomponent seismic data of M area in Canada, the logging response characteristics of the reservoir are analyzed and the sensitive parameters are optimized. The PP and PS joint inversion, characteristic curve inversion and lithofacies probability simulation are integrated to increase the precision of reservoir prediction gradually. The application results show that, due to the reservoir prediction based on joint inversion, the top and bottom interface of oil sands reservoir and the distribution of interbed are described in detail. And important geophysical prospecting results are provided for oil sands development in this area.
Presentation Date: Monday, October 15, 2018
Start Time: 1:50:00 PM
Location: 213A (Anaheim Convention Center)
Presentation Type: Oral
However, in mountain seismic exploration, the terrain is With regards to mountain seismic exploration, due to the undulating and doesn't satisfy the horizontal surface undulating topography the Herglotz-Wiechert formula assumption of the Herglotz-Wiechert formula. In the case can't be directly applied to invert the near-surface velocity of the rugged topography, it is difficult to accurately derive structure. This paper introduces a fast algorithm to estimate the instantaneous slowness of the turning point through the the near-surface velocity-depth function associated with apparent slowness of diving wave traveltime-distance the rugged topography, utilizing the traveltime-distance curve. Because a shot gather is involved in a source and a curve of first arrivals in CMP domain. This method number of receivers, the positions of turning points of the employs the concept of CMP floating datum corrections of diving waves corresponding to different receivers on the seismic reflection, consisting of four steps: CMP floating rugged surface don't concentrate to a single point but datum construction, traveltime-distance curve corrections, distribute in a region on the horizontal plane. Thus, those instantaneous ray parameter estimation, and velocity-depth inversion techniques in shot domain can only estimate the function estimation. Not only does this method not require average value of the turning point positions over a spread ray tracing and initial velocity model, it also has a fast length, which will cause poor horizontal resolution in areas computational speed. The inverted result has the same of complex subsurface geology. Furthermore, the horizontal resolution as the seismic data, allowing it to be sparseness of the shot points will further lower the used for the calculation of datum statics, near surface horizontal resolution of the inversion in shot domain.
SAGD (steam assisted gravity drainage) Multi-wave seismic exploration, which utilizes P-wave, S-development is applied in the area and it requires high wave and PSwave, is an effective method for the fine precision prediction on oil sand reservoirs in order to exploration of petroliferous basin. The oil sands in the improve the development efficiency. The survey is MacKay region are mainly lithologic reservoirs, which vary influenced by the Quaternary glacial motion so the swamp laterally. The swamp area in the surface is very big and area is very big and distributed in unbalance and the near distributed in unbalance. The near surface is complex and surface is complex and varied, which is influenced by the varied. The PSwave residual statics is obtained by the quaternary glacier movement in the Canadian MacKay common receiver point stack cross-correlation method region. The problem of P-wave static correction is severe - controlled by PP and PSwave structure time and the and that of PSwave data is even worse. The unusually integrated global optimized static correction method.
However, excessive acquisition cost The exploration of oil and gas has been restrained from restrains the production application of high density 3D further breakthroughs due to the low SNR (signal to noise seismic exploration. Therefore, it is of great importance to ratio) of seismic data and high investment in foothills substantially decrease the acquisition cost by carrying out regions in western china. In this abstract, a 3D geometry key parameters tests and hence obtaining optimized design key parameters test method is proposed for optimizing high of high density 3D seismic geometry.