The tectonic boundary between the Okcheon and Taebaeksan basins, South Korea: A restraining bend of a continental transform fault between the South and North China Cratons

• Published in: The island arc 2018-03, Vol.27 (2), p.n/a
• Main Authors: Kim, Hyeong Soo, Ree, Jin‐Han, Yi, Keewook
• Format: Article
• Language: English
• Subjects: Basins; continental transform fault; Cratons; Deformation; Geological time; Korean peninsula; Okcheon Basin; Permian; Rock; Rocks; Taebaeksan basin; Thrust; Transform faults; Triassic
• ISSN: 1038-4871; 1440-1738
• DOI: 10.1111/iar.12237

The geological relationship between the Okcheon and Taebaeksan basins of the Okcheon belt on the Korean peninsula is a key issue in reconstructing the tectonic evolution of the peninsula. The boundary between the two basin sequences has been variously interpreted as a conformable, unconformable, or thrust contact, without clear evidence being provided for any of these hypotheses. Detailed examination of structures and microfabrics of deformed rocks adjacent to the contact in the Bonghwajae area suggests that the boundary between the two basin sequences is a thrust. Based on the U–Pb ages of detrital zircons from metasedimentary rocks and pre‐existing geologic data from the Okcheon belt, the thrust is a relay structure between two segments of a continental transform fault along which the Okcheon Basin was juxtaposed against the Taebaeksan Basin during the Permian–Triassic suturing of the North and South China Cratons. 沃川帯の沃川盆地と太白山盆地の間の地質学的関係は韓半島の構造発達史の復元において重要な問題である.  これまで2つの盆地の地層の境界は,  明瞭な証拠のないまま,  整合,  不整合,  あるいは衝上断層と解釈されてきた.  今回,  ボンファジェ地域の変形岩石の構造とマイクロファブリックを詳細に検討した結果,  2つの盆地の地層は衝上断層で境されていることを示唆する.  砕屑性ジルコンのウラン −鉛年代と既存の地質学的知見に基づくと,  衝上断層は沃川盆地に沿った大陸トランスフォーム断層の2つの断層セグメント間のリレー構造である.  沃川盆地はペルム・トリアス紀の南・北中国クラトンの縫合時期に太白山盆地に対して並置された. The geological relationship between the Okcheon and Taebaeksan basins of the Okcheon belt on the Korean peninsula is a key issue in reconstructing the tectonic evolution of the peninsula. Detailed examination of structures and microfabrics of deformed rocks adjacent to the contact in the Bonghwajae area suggests that the boundary between the two basin sequences is a thrust representing a relay structure between two segments of a continental transform fault during the Permian–Triassic suturing of the North and South China Cratons.