Junior Deeper graduated ! - Deep Hydrografie en Geofysica

Junior Deeper graduated !


Backscatter data from Wemeldinge Oost at 400 KHz frequency acquired via a R2Sonic 2024

Backscatter data from Wemeldinge Oost at 400 KHz frequency acquired via a R2Sonic 2024

“When you stand at the edge of IMG-20190321-WA0012 2everything you know, one of two things will happen when you take a leap; either there will be firm ground or you will learn how to swim”. With these words Akul Chopra, now a junior Deeper, turned to the sea for a career!

Having studied Geography, Oceanography and Hydrography, Akul found Deep at Hydro 2017, Rotterdam where he met Gert-Jan Siepel and Jurgen Beerens. This summer he finished his studies from HafenCity University, Hamburg, where he completed a Master’s in Geomatics. As a requirement for his master’s, he wrote a thesis with the topic Backscatter surveying. While writing his thesis, Akul received all the support and motivation he needed from his fellow Deepers and colleagues at QPS B.V.

The topic involved understanding the intricacies of monospectral and multispectral backscatter and comparing them. It entailed first, to build a theoretical knowledge base in the topic of backscatter, going on to learning processing of backscatter data, to finally learning how to acquire it. For the purpose of comparing the monospectral and multispectral backscatter, he used a Kongsberg EM2040 compact dual head for the former and an R2Sonic 2024 for the latter. With the intention of helping Deep to increase its backscatter capacity via this thesis, he focused on understanding which signal regime is best for backscatter so that Deep can offer its clients the best products possible. He used QPS Qimera to process the bathymetry and Fledermaus Geocoder Toolbox to process the backscatter. Backscatter is the property of the seabed by virtue of which it returns a signal in the direction of an active sonar, where the intensity of the backscatter can be used as a proxy for the geotechnical properties of the surficial sediments. With this knowledge, he hopes to be an asset to Deep, which is currently involved with Rijkswaterstaat in analyzing backscatter from Zeeland, Netherlands.

The primary conclusion of his thesis is that a multi-frequency dataset using the monospectral signal regime is a better option for acquiring backscatter even though the new multispectral mode will save plenty of time to generate the same multi-frequency datasets in one single pass. Akul believes that the monospectral signal regime is better at representing backscatter and that it generates better results using the Angle-Range-Analysis algorithm in FMGT, which currently is the leading tool for gauging the geotechnical properties of the seabed remotely without acquiring a grab sample.

But for now, Akul is focussing is on becoming a competent Hydrographer at Deep. He will soon be back in the environment he loves the most, doing what he loves the most. “When you love your job so much, it doesn’t feel like work anymore, every day is an adventure with never a dull moment!”