Seismic Signature of Hydrocarbon Leakage from a Frigg Structure in the North Sea

There exist some remarkable, shallow anomalies above the Eocene Frigg Gamma structure in the northern North Sea. The anomalies formed as a result of huge hydrocarbon leakage from the Frigg Gamma structure. Biodegradation processes resulted in extensive calcite cementation that occurs in a zone of more than 400 m in the Miocene sandy section.