A hydrocarbon microtremor survey over a gas field: Identification of seismic attributs
Published in
SEG/San Antonio 2007 Annual Meeting
Publication date
24 September 2007
Abstract
Narrow-band, low-frequency (from ~1H to ~6Hz) microtremor signals have been observed worldwide at the surface over hydrocarbon reservoi rs (oi l, gas and water multiphase fluid systems in porous media). These low-frequency hydrocarbon microtremors possess remarkably similar spectral and signal structure characteristics, pointing to a common source mechanism, even though the depth (some hundreds to several thousands of meters), specific fluid content (oil, gas, gas condensate of different compositions and combinations) and reservoir rock type (such as sandstone, ca bonates, etc.) for each of those sites are quite different. In this extended abstract we describe some results of an extensive low-frequency hydrocarbon microtremor survey carried out in Mexico. We describe how we extract a hydrocarbon potential map from spectral anomalies and compare this map with available reservoir location data. In a detailed analysis of two representative stations of the survey we extract different seismic attributes. Those attributes are compared with a theoretical model which can explain the source mechanism of hydrocarbon microtremors.
