Seismic interferometry by crosscorrelation and by multidimensional deconvolution: a systematic comparison
نویسندگان
چکیده
Seismic interferometry, also known as Green’s function retrieval by crosscorrelation, has a wide range of applications, ranging from surface-wave tomography using ambient noise, to creating virtual sources for improved reflection seismology. Despite its successful applications, the crosscorrelation approach also has its limitations. The main underlying assumptions are that the medium is lossless and that the wave field is equipartitioned. These assumptions are in practice often violated: the medium of interest is often illuminated from one side only, the sources may be irregularly distributed, and losses may be significant. These limitations may partly be overcome by reformulating seismic interferometry as a multidimensional deconvolution (MDD) process. We present a systematic analysis of seismic interferometry by crosscorrelation and by MDD. We show that for the non-ideal situations mentioned above, the correlation function is proportional to a Green’s function with a blurred source. The source blurring is quantified by a so-called interferometric point-spread function which, like the correlation function, can be derived from the observed data (i.e., without the need to know the sources and the medium). The source of the Green’s function obtained by the correlation method can be deblurred by deconvolving the correlation function for the point-spread function. This is the essence of seismic interferometry by MDD. We illustrate the crosscorrelation and MDD methods for controlled-source and passive-data applications with numerical examples and discuss the advantages and limitations of both methods.
منابع مشابه
On the relation between seismic interferometry and the simultaneoussource method
In seismic interferometry the response to a virtual source is created from responses to sequential transient or simultaneous noise sources. Most methods use crosscorrelation, but recently seismic interferometry by multidimensional deconvolution (MDD) has been proposed as well. In the simultaneous-source method (also known as blended acquisition), overlapping responses to sources with small time...
متن کاملControlled-source interferometric redatuming by crosscorrelation and multidimensional deconvolution in elastic media
Various researchers have shown that accurate redatuming of controlled seismic sources to downhole receiver locations can be achieved without requiring a velocity model. By placing receivers in a horizontal or deviated well and turning them into virtual sources, accurate images can be obtained even below a complex near-subsurface. Examples include controlled-source interferometry and the virtual...
متن کاملSeismic interferometry, intrinsic losses and Q-estimation∗
Seismic interferometry is the process of generating new seismic traces from the crosscorrelation, convolution or deconvolution of existing traces. One of the starting assumptions for deriving the representations for seismic interferometry by crosscorrelation is that there is no intrinsic loss in the medium where the recordings are performed. In practice, this condition is not always met. Here, ...
متن کاملGreen’s function representation for seismic interferometry by deconvolution
Despite the strength of seismic interferometry to retrieve new seismic responses by crosscorrelating observations at different receiver locations, the method relies on a number of assumptions which are not always fulfilled in practice. Some practical circumstances that may hamper interferometry by crosscorrelation are: one-sided illumination, irregular source distribution, varying source spectr...
متن کاملTutorial on seismic interferometry. Part II: Underlying theory and new advances
In part II of this two-part tutorial we review the underlying theory of seismic interferometry and discuss various new advances. In the 1990’s the method of time-reversed acoustics was developed. This method employs the fact that the acoustic wave equation for a lossless medium is invariant for time-reversal. When ultrasonic responses recorded by piezoelectric transducers are reversed in time a...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2011