Depth Migration Velocity: Differential Semblance Analysis for Sumatra Forearch Basin

2nd Southeast Asian Conference on Geophysics

Putra, A.S.^1 ; Sismanto^1 ; Alam, I.S.^2

Geophysics Division, Department of Physics, Faculty of Mathematics and Natural Science, Universitas Gadjah Mada, Yogyakarta

55281, Indonesia^1

Physics Division, Department of Physics, Faculty of Mathematics and Natural Science, Universitas Gadjah Mada, Yogyakarta

55281, Indonesia^2

关键词: Depth migration;    Interval models;    Low velocity zones;    Migration velocity;    Reflectance data;    RMS velocities;    Semblance analysis;    Travel time data;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/318/1/012012/pdf
DOI  :  10.1088/1755-1315/318/1/012012

来源: IOP

【 摘 要 】

The specific goal of this work is to present a complete velocity map obtained by picking the velocity in Common Image Gather (CIG) map. We simulated a shot gather in order to obtain a synthetic travel time data for depth analysis. We successfully determined the correct migration velocity and presented the velocity interval model. For further study, we also conducted a Semblance analysis in order to obtain a coherency panel between the energy and the depth migration velocity analysis. We successfully interpreted the conventional semblance profile that the correct velocity model maximizes that energy which is represent higher value. For the real case, The data set was acquired by CGGVeritas in 2009 of RMS velocities recorded in 48 CMP points. The results of the semblance analysis shows well coherence with the seismic reflectance data that reveals the Low Velocity Zone of Sumatra fault related to the present of fluid and gas.