Extending Low Frequencies With A Conventional Airgun Arrays Using Frequency Locking

Summary

Recently, towed marine seismic acquisitions are intently focusing on enhancing low frequencies on the source and receiver side. In this workshop we document our journey to enhance the low- frequency output of airgun arrays for towed marine seismic acquisitions. We show the physical effect of (partial) frequency locking of the pressure field from adjacent airguns or clusters, which can give a larger effective bubble volume, lower the oscillation frequency, and thus increase the low- frequency content emitted over a traditional design in which frequency locking does not occur. We present details and results from our field experiments and show that we achieved consistent and repeatable partial frequency locking with a 70% increase in effective bubble volume for a 2-cluster scenario and a 95% increase for a 3-cluster scenario, respectively.