Schlumberger seismic vessel Western Monarch is gathering the data for the survey, which completes the licence requirements for the first phase on the block awarded in 2011.
The block spans 4191 square kilometres altogether of the Makassar Strait in water depths ranging from 20 metres to more than 100 metres.
KrisEnergy exploration and production director Chris Gibson-Robinson said the survey aimed to “help us to identify and map several more prospects and leads in the portion of the block that lies in the shallower areas”.
Three wells have previously been drilled on the block by Hess Corporation, two of them finding gas.
KrisEnergy operates the licence on a 43% interest with Neon Energy on 42% and Natuna Ventures on 15%.