Passive Seismic Survey Project
Following the successful completion of first phase of the Passive Seismic survey in West Tripura, ONGC decided to proceed to the Phase-II. The scope of work was a detailed 3D velocity model of the study area, down to at least 6km depth, however the model finally delivered reached out 30km. The results of the PST survey were used as complementary information to the existing or newly acquired 2D/3D reflection seismic data, aiming to benefit the hydrocarbon exploration program in Tripura.
A seismic network composed of 348, 3-compnenent seismic stations (340 short-period and 8 broadband) were installed in a very challenging area of about 5,000 sq.km with lots of accessibility and complex geotectonic issues . The average interstation distance was 2.5 km and the data recording period was 8 months.
The data acquisition stage was successfully completed on 20.02.2022, overcoming the difficulties that incurred because of the monsoons or the spread of Covid-19. The processing/interpretation work was completed in June 2022. The PST results were evaluated using existing well and geological data giving excellent matching.