Full text loading...
-
IS IT POSSIBLE TO INCREASE THE RESOLUTION IN SEISMIC EXPLORATION FOR COAL BY USING HIGH FREQUENCY SIGNALS?*
- Source: Geophysical Prospecting, Volume 33, Issue 8, Dec 1985, p. 1160 - 1173
-
- 27 Apr 2006
Abstract
In seismic exploration for coal data resolution is a fundamental problem. Modeling helps to understand those details of the geology that can be interpreted from the seismic image. For single seam exploration, the vertical resolution of a seismic section is defined by the bandwidth of the signals. If there are several seams, each seam acts as a high‐pass filter for reflections and as a low‐pass filter for transmitted waves. Synthetic seismograms show that reflections from deep seams have a low frequency content.
Within a layered sequence of coal seams, many multiples are generated which disturb later primary reflections. The ratio of primaries to multiples depends on the frequency content of the seismic data and on the number of overlying seams. The multiple problem is more severe with high frequencies.
Primary reflections from deep coal seams within a sequence can be detected only if low‐frequency signals are used. However, the use of low‐frequency signals reduces the resolution of the deeper data.