BACKGROUND
A seismic survey is designed to image or map the subsurface of the earth by sending energy generated by a seismic source down into the ground and recording the “echoes” that return from the rock layers below. The source of seismic energy might be, for example, explosions or seismic vibrators on land or air guns in marine environments. During a seismic survey, the source is positioned at various locations near the earth's surface above a geologic structure of interest. Each time the source is activated, it generates a signal that travels downward through the earth, is reflected, and, upon its return, is recorded at many locations on the surface. The returning seismic energy might be recorded by geophones on land or by hydrophones in a marine environment. The signal produced by a source activation is typically referred to as the signature of that source.
SUMMARY OF TECHNOLOGY
As a crucial step in seismic data analysis, source signature estimation improves the resolution and accuracy of subsurface seismic imaging; however, its effectiveness directly relates to the quality of the recorded or estimated source signature. Because of data acquisition challenges, recording the source signature in field conditions may not be straightforward in marine and land data. Estimation of source signature is also extremely challenging due to its non-stationary inherent, distance between the source and sensors (hydrophone or geophone), and the existence of the different types of noises, especially in land-data that are acquired with a hammer or implosive sources. The method is herein presented to estimate the source signature directly from near-field data. This method can be used for marine and land data; it constantly reconstructs a minimum-phase source signature with the minimum error estimation.
POTENTIAL AREAS OF APPLICATION
MAIN ADVANTAGES
STAGE OF DEVELOPMENT
A working model is available.