نتایج جستجو برای: e. g. kirchhoff migration operator

تعداد نتایج: 1598128  

Journal: :فیزیک زمین و فضا 0
مهرداد سلیمانی منفرد عضو هیات علمی علی خلیل زاده دانش آموخته کارشناسی ارشد/دانشگاه شاهرود

the conventional approach to seismic data analysis consists of two main steps: estimating seismic velocities, (the subsurface macro-model), and seismic imaging, (mapping of the reflected seismic energy to the reflector positions). the aim and the major challenge in the seismic data analysis is the construction of the best undistorted image. this challenge would be more problematic when geometri...

Journal: :Applied Mathematics and Computation 2005
João Luiz Martins

Two important tools in seismic processing––Kirchhoff migration and demigration operators––are the basis for many imaging problems solution. Due to high numerical and computational requirements, the use of those tools for three dimensions are very computation-costly. This fact has motivated us to investigate Kirchhoff migration operations for simpler types of media in order to provide faster res...

1998
Jing Chen

Application of least-squares Kirchhoff migration (LSM) to synthetic reverse vertical seismic profile data (RVSP) demonstrates that LSM reduces the migration artifacts, improves the image resolution and produces a more accurate image than the standard migration, but cannot completely recover the model reflectivity for AVO analysis because of the limited data coverage. The influence of incomplete...

2003
Jianhua Yu

Both migration deconvolution (MD) and least squares migration (LSM) are capable of improving the resolution and suppress acquisition footprints in migrated images. In this paper, we investigate the relative performance of these two technologies in enhancing migration image quality, suppressing artifacts and computational efficiency. Both MD and LSM were tested on SEG/EAGE overthrust models. The...

Journal: :فیزیک زمین و فضا 0
پویا هادیان اداره ژئوفیزیک، مدیریت شرکت ملی نفت ایران، تهران، ایران عبدالرحیم جواهریان استاد بازنشسته، گروه فیزیک زمین، مؤسسه ژئوفیزیک، دانشگاه تهران و استاد دانشکده مهندسی نفت دانشگاه صنعتی امیرکبیر، تهران، ایران بهزاد نظری مرکز پردازش، شرکت عملیات اکتشاف نفت، تهران، ایران

in exploration seismology, migration refers to a multi-channel processing step that attempts to spatially re-position events and improve focusing. before migration, seismic data is usually displayed with traces plotted at the surface location of the receivers and with a vertical time axis. this means that dipping reflections are systematically mispositioned in the lateral coordinate and the ver...

Let $G=(V,E)$, $V={1,2,ldots,n}$, $E={e_1,e_2,ldots,e_m}$,be a simple connected graph, with sequence of vertex degrees$Delta =d_1geq d_2geqcdotsgeq d_n=delta >0$ and Laplacian eigenvalues$mu_1geq mu_2geqcdotsgeqmu_{n-1}>mu_n=0$. Denote by $Kf(G)=nsum_{i=1}^{n-1}frac{1}{mu_i}$ and $t=t(G)=frac 1n prod_{i=1}^{n-1} mu_i$ the Kirchhoff index and number of spanning tree...

1997
Gerard T. Schuster

Least squares migration (LSM) is applied to 3-D synthetic data in order to test the feasibility of removing the ”recording footprint” noise from migrated sections. The LSM algorithm is implemented with a conjugate gradient algorithm. Results for simple point scatterer and meandering stream channel models suggest that LSM can significantly attenuate the recording footprint noise. For comparison,...

2002

Wave-equation migration is an accurate and robust alternative to Kirchhoff migration when multipathing and other complex wave phenomena occur, such as in subsalt exploration. In these situations, images obtained by wave-equation migration are often superior to images obtained by Kirchhoff methods. However, 3-D wave-equation prestack imaging is an immature technology compared with Kirchhoff imag...

2017
Lorenzo Casasanta Francesco Perrone Graham Roberts Andrew Ratcliffe Karen Purcell Arash JafarGandomi

It is well-known that standard migration is not a true inverse operation and is based on the adjoint of the forward modeling operator. Due to this approximation the resulting migrated image can often suffer from various artifacts and uneven illumination issues, especially in regions of complex geology. Least-squares depth migration approximates the inverse of the forward modeling and can be use...

1999
Biondo Biondi

The comparison of subsalt images obtained by common-azimuth migration and singlearrival Kirchhoff migration demonstrates the potential of wave-equation migration when the velocity model causes complex multipathing. Subsalt reflectors are better imaged and the typical Kirchhoff artifacts caused by severe multipathing disappear. A detailed analysis of common-azimuth images indicates that the resu...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید