Application of Kirchhoff Prestack Time Migration Method of the 2D Marine Seismic Data for Mapping the Subsurface Structures in Dip Case Southern Aru, West Papua, Indonesia Hani Yusrina Safura (a*), Andrian Wilyan Djaja (b), Nanang Dwi Ardi (a), Priatin Hadi Wijaya (b)
a) Physics Studies Program, Indonesia University of Education , Jl. Dr. Setiabudhi No. 229, Bandung 40154, Indonesia
*haniyusrina.19[at]student.upi.edu
b) Center for Research and Development of Marine Geology, Jl. Dr. Djunjunan No.236, Bandung 40174, Indonesia
Abstract
The natural resources of oil and gas potential in the West Papua waters constitute a significant expansion of oil and gas investments in Indonesias maritime specifically the eastern region. South Aru is located at the eastern edge of the basin trough Aru and includes one of the most potential oil and gas basins. Complex geological structures such as the case of large dip make seismic cross section results do not represent the subsurface structure of the earth nearing the actual subsurface geological conditions. The working principle of Kirchhoff Prestack Time Migration is looking for reflector positions using delay time of wave energy reflection to get a better seismic section on the tilted reflector with less diffraction effect and have little effect arch (smiling effect) which generates seismic section that can represent the subsurface structure of the earth. However, Kirchhoff Prestack Time Migration has a weakness, namely the inability to represent seismic sections accurately when there is a complex velocity structure due to approximations used in representing and calculating green functions, wave travel time and amplitude. The research data were analyzed is multichannel reflection seismic data of marine zones, namely the line 12th of the South Aru, West Papua waters. The results obtained in the form of time migrated section are analyzed based on their reflectivity In this research found that the cross section of the subsurface structure represented by a migrated seismic section amounted overall in 6107 CDP, along the path as far as 110 km with CDP space is 12.5 m with reflectivity cross section of generally more clearly observed after the migration process is carried out so that the resolution of cross section seismic better than that have not been migrated seismic section, which can be useful as the data is ready to be interpreted as the purposes of determination prospects of natural resources, especially regarding the hydrocarbon potential of the South Aru, West Papua waters.
Keywords: Kirchhoff Prestack Time Migration, Seismic Reflection, Time Migrated Section, Dip, Complex
