TY - JOUR
T1 - Influence of faults and slumping on hydrocarbon migration inferred from 3D seismic attributes
T2 - Sanriku-Oki forearc basin, northeast Japan
AU - Eng, Chandoeun
AU - Tsuji, Takeshi
N1 - Funding Information:
We thank Ministry of Economy, Trade and Industry Japan (METI) and Japan Oil, Gas and Metals National Corporation (JOGMEC) for providing the 3D seismic data acquired through METI Geophysical Survey and Basin Evaluation Project “Sanriku-Oki 3D”. We further thank Japan Agency for Marine-Earth Science and Technology (JAMSTEC) for providing the 2D seismic and logging data. We are grateful to O. Takano (JAPEX) for valuable discussions, associate editor D. Praeg, and T.M. Alves and D. Gamboa for constructive reviews of the manuscript. We gratefully acknowledge the support of the Japan International Cooperation Agency , and International Institute for Carbon-Neutral Energy Research sponsored by the World Premier International Research Center Initiative (WPI), MEXT, Japan .
Publisher Copyright:
© 2018 Elsevier Ltd
PY - 2019/1
Y1 - 2019/1
N2 - Seismic imaging of the Sanriku-Oki forearc basin in the Japan Trench plate convergent margin provides insights into the geological controls on hydrocarbon systems in sediment deposited on the continental slope. We perform a series of seismic attribute analyses on 3D seismic reflection data to better define the influence of geological structures (e.g., faults, slumps and gas chimneys) on hydrocarbon sources, migration pathways and reservoirs. In order to identify coal-bearing strata from the 3D seismic volume, we calculate acoustic impedance distribution by integrating seismic and logging data via waveform inversion. Two Late Oligocene to Early Miocene major coal-bearing strata are characterized as low acoustic impedance strata. Gas-bearing strata characterized by anomalously high reflection strength are widely distributed beneath a bottom simulating reflector (BSR). A greater accumulation of gas occurs in the northeast of the study area, where successive slump deposits and gas chimneys are observed. We propose that a BSR with an underlying gas accumulation in the Sanriku-Oki forearc basin developed as a consequence of the expulsion of gas from Cretaceous to Oligocene coal beds and their subsequent upward migration through gas chimneys and faults. Furthermore, the migration and accumulation of gas and gas hydrate were strongly controlled by a series of porous slump deposits. As chimneys and gas pockets occur above the edges of the slumps, gas migration processes controlled by the slumps could be important in the forearc basin. Our study based on seismic attribute analyses demonstrates that features produced by tectonic movements at plate subduction margins (e.g., faults) and associated instability processes (e.g., slumps) represent important controls on the migration and accumulation of hydrocarbons in forearc basins.
AB - Seismic imaging of the Sanriku-Oki forearc basin in the Japan Trench plate convergent margin provides insights into the geological controls on hydrocarbon systems in sediment deposited on the continental slope. We perform a series of seismic attribute analyses on 3D seismic reflection data to better define the influence of geological structures (e.g., faults, slumps and gas chimneys) on hydrocarbon sources, migration pathways and reservoirs. In order to identify coal-bearing strata from the 3D seismic volume, we calculate acoustic impedance distribution by integrating seismic and logging data via waveform inversion. Two Late Oligocene to Early Miocene major coal-bearing strata are characterized as low acoustic impedance strata. Gas-bearing strata characterized by anomalously high reflection strength are widely distributed beneath a bottom simulating reflector (BSR). A greater accumulation of gas occurs in the northeast of the study area, where successive slump deposits and gas chimneys are observed. We propose that a BSR with an underlying gas accumulation in the Sanriku-Oki forearc basin developed as a consequence of the expulsion of gas from Cretaceous to Oligocene coal beds and their subsequent upward migration through gas chimneys and faults. Furthermore, the migration and accumulation of gas and gas hydrate were strongly controlled by a series of porous slump deposits. As chimneys and gas pockets occur above the edges of the slumps, gas migration processes controlled by the slumps could be important in the forearc basin. Our study based on seismic attribute analyses demonstrates that features produced by tectonic movements at plate subduction margins (e.g., faults) and associated instability processes (e.g., slumps) represent important controls on the migration and accumulation of hydrocarbons in forearc basins.
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U2 - 10.1016/j.marpetgeo.2018.10.013
DO - 10.1016/j.marpetgeo.2018.10.013
M3 - Article
AN - SCOPUS:85054927428
VL - 99
SP - 175
EP - 189
JO - Marine and Petroleum Geology
JF - Marine and Petroleum Geology
SN - 0264-8172
ER -