Getting the bubble balance right

Shearwater’s enhanced low-frequency source, Harmony, was hard at work off the coast of Malaysia recently, where it was used in a hybrid mode with a conventional source. The new survey is designed to bring new geological clarity to an area well known for difficulties with the quality of seismic data, but which is also well known for its hydrocarbon potential!

Joining forces between conventional and the Harmony source technology means the client can realise the potential of both, without compromise – something the client wanted – the best quality seismic data to help promote every basin to potential investors and open new plays, such as the pre-Tertiary here.

Our vessel, SW Thuridor, completed the survey safely and on schedule, but how exactly will our client benefit from the added power of Harmony?

Better decision making

One geophysical objective is to improve on the poor signal penetration to and below complex carbonates. Adding low frequencies can help with this, as lows are attenuated less than high frequencies. The positives from lows are the impact on the velocity model with superior full wave inversion results -- or even just better conventional depth tomography with better horizon continuity. And a better velocity model means better images as more of the
seismic energy focuses during imaging, improving the signal over the noise. Good quality low frequencies and the velocity model will also benefit the fault plane imaging and definition resulting in better interpretation. Through this, we will understand better than ever, ultimately leading to better drilling decisions.

How does Harmony work?

Harmony generates low frequencies by using the physical process of frequency locking, where pressure fields between the bubbles interact. It also integrates seamlessly in our existing source strings and can be deployed on any of our vessels providing a safe and robust source.

Harmony boasts a remarkable downward shift of half to one octave in the dominant frequency. For clients, this translates to a deeper understanding of the sub-surface terrain.

Harmony operates in many modes, a flexibility that comes from using only one air source string. That means that can combine Harmony with other air source designs, in single and multi-source modes, or for long-offsets – however you need it.