Full text loading...
-
Коррекция статических поправок с сохранением кинематики отраженных волн, соответствующих пластовой модели среды
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, Geomodel 2012 - 14th EAGE science and applied research conference on oil and gas geological exploration and development, Sep 2012, cp-308-00025
- ISBN: 978-90-73834-36-1
Abstract
Almost all areas of seismic explorations doing on a land are characterized by presence of low-velocity zone in combination with varying surface relief. Both of these factors distort seismic information coming up from deeper target horizons. In order to exclude their effect usually use time shifts – statics. Wavefield redatuming is based on an assumption that ray paths of reflected waves between observation surface and datum surface are vertical in spite of source-receiver offset. But the assumption about vertical ray paths is relatively exact only in interval, limited by observation surface and low-velocity zone bottom. That’s why it’s desirable to set datum surface as closely to low-velocity zone bottom as possible, because otherwise NMO of the reflectors would be distorted. The best way is to identify low-velocity zone bottom and datum surface, and to use more proper methods (e. g. wavefield transform) for wavefield redatuming to any datum surface. But if the datum surface isn’t flat the hodograph of the reflected waves would have very difficult form, that distinct from hyperbola drastically. So, conventional methods based on assumption of hyperbolical form of hodographs aren’t applicable. In this paper we suggest a new method for statics correction based on kinematic-dynamic transformation developed in Seismotech, Ltd.