High amplitude seismic anomalies are found to be commonly distributed within Paleogene strata in Liaodong Depression, Bohai Oilfield, which may be associated with the presence of hydrocarbon. In this paper, we have attempted to reveal the formation mechanism and then characterize the hydrocarbon prospects as well as spatial distribution of such bright spots. The research starts by rock physics analyzing of the drilled wells and forward modeling, which shows that gas sand with relatively low impedance and gravel sand with relatively high impedance both manifest as strong amplitude reflections. However, spectrum analysis demonstrates the differences between them in dominant frequency and bandwidth, and the result is further confirmed by spectral decomposition. The hydrocarbon-associated seismic anomalies are therefore distinguished from those "false bright spots" caused by other geologic factors through low-pass filtering based peak energy sum, which is then followed by frequency attenuation gradient (FAG) analysis for more accurate distribution of favorable areas and further risk mitigation.
Presentation Date: Thursday, October 18, 2018
Start Time: 8:30:00 AM
Location: 209A (Anaheim Convention Center)
Presentation Type: Oral
