Natuna D-Alpha | PGS

Natuna Basin - Indonesia - 2010

Natuna D-Alpha 3D

High Definition MultiClient 3D data over the giant D-Alpha structure, offshore Indonesia
Website Map for Survey Natuna D-Alpha
The survey was acquired in cooperation with MIGAS (Ministry of Energy and Mineral Resources, Directorate General of Oil and Gas) over the D-Alpha structure, a middle to late Miocene platform reef carbonate which lies approximately 200 km northeast of Natuna Island.
The D-Alpha structure has gas reserves of more than 200 Tcf attributed to it, although over 70% is considered to be CO2. With such high CO2 it was deemed important for the safety and planning of development to have a high quality 3D image of the field, since a 1% error for engineering could be 2Tcf.
725 sq km of High Definition MultiClient 3D data over the giant D-Alpha gas field ensured that subtle faulting and internal features of the reef could be clearly imaged.


Survey summary

  • Type: 3D
  • Geometry: Standard
  • Size: 725
  • Acquisition year: 2010
  • Completion of processing: 2011
  • Water depth: 130 m
  • Shooting direction: NNW-SSE
  • Vessel: Pacific
  • In partnership with: MIGAS

Acquisition parameters

  • Number of streamers: 8
  • Streamer length: 5100 m
  • Streamer separation: 75 m
  • Shot interval: 18.75 m
  • Record length: 7168 ms
  • Sample rate: 2 ms
  • Bin dimensions (Acquisition): 6.25 x 18.75 m
  • Bin dimensions (Processing): 12.5 x 9.375 m
  • Fold: 68


  • 2D surface related multiple elimination (SRME)
  • High resolution radon demultiple
  • Kirchhoff prestack time migration (PSTM)
  • XT / Tau-P Deconvolution

Time products

  • Final Kirchhoff PSTM Stack
  • PSTM gathers
  • Stacking velocity
  • Migration velocity
  • Angle Stack

Additional products

  • Interpretation