|Table of Contents|

Theory of Kirchhoff-type High Fidelity Demigration(PDF)

《地球科学与环境学报》[ISSN:1672-6561/CN:61-1423/P]

Issue:
2011年第02期
Page:
207-212,216
Research Field:
应用地球物理
Publishing date:

Info

Title:
Theory of Kirchhoff-type High Fidelity Demigration
Author(s):
SUN Jian-guo1; 2
1. School of Geoexploration Science and Technology, Jilin University, Changchun 130026, Jilin, China; 2. Laboratory for Integrated Geophysical Interpretation Theory and Laboratory for Wave Theory and Imaging Technology of Ministry of Land and Resources, J
Keywords:
Kirchhoff-type demigration;  amplitude distortion;  multiple-weighted isochrone stack;  high fidelity
PACS:
P631
DOI:
-
Abstract:
For making the output of Kirchhoff-type demigration equal to the output of numerical modeling,we present a demigration method called high fidelity demigration,which is able to eliminate the amplitude distortion effect in Kirchhoff-type demigration. Different from the conventional Kirchhoff-type demigration,the high fidelity demigration is reflector-dependent. As a result,in high fidelity demigration we first need to determine the position of the reflector, then to determine the amplitude distortion factor,and finally to correct the demigration amplitude according to the fact that the amplitude distortion factor in demigration is equal to one at a reflection point. In practical implementation of high fidelity demigration, we use four weighting functions in a single weighted isocheone stack, namely the unit weighting function, the conventional true amplitude weighting function, and the two horizontal coordinates of the global coordinate system that is used for establishing the Kirchhoff-type demigration operator. By performing division operations among the four dimigrated images, we can extract the position of the reflection point and the amplitude distortion factor. Once the position of the reflection point and the amplitude distortion factor are obtained, the amplitude distortion effect in demigration can be corrected by a simple division.

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Memo

Memo:
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Last Update: 2011-06-20