Hydrocarbon Potential of the New Play Concept in the Ulleung Basin, East Sea, Offshore Korea

Lee, KyoungA; Kim, Seokjin; Lee, Jungmin; Song, Byeongchan; Kim, Yumi; Woo, Byeongkwon; Choi, Byeonggoo
Korea National Oil Corporation, Anyang, Korea, Republic of.

The Tertiary sedimentary Ulleung Basin had provided limited exploration potentials due to lack of effective structures. Only a field had produced gas and condensate from a combination trap related with shale filled submarine canyons truncated a plunging fold nose. Compressive stresses caused by subduction of the Pacific Plate generated foldings and strike-slip movements deformed them within the Miocene. Several structures of the deformed area were drilled and classified as non-commercial discoveries. Hydrocarbon explorations outside of the deformed area had difficulties to identify structures from gently monocline features. As a result of the integrated structural and stratigraphic frameworks, a new play associated with turbidite sandstones in the Early Miocene was recognized. Conventional seismic data evaluations including seismic facies mapping and seismic attribute analysis had applied for recognition of submarine fans and identified some distinct shapes from coeval seismic horizons which were drilled in the deformed area. Development of submarine fans across the monocline provided combination traps in the outside of deformed area which were hardly found structural traps. It was rare to find only one field in a normal size sedimentary basin. The new play concept based on conventional integrated interpretations has been generated for explorations of untapped hydrocarbons in the unexplored area and expected to provide new fields in the Ullueng Basin.

AAPG Search and Discovery Article #90155©2012 AAPG International Conference & Exhibition, Singapore, 16-19 September 2012