Evolution of the Taebaeksan Basin, Korea: I, early Paleozoic sedimentation in an epeiric sea and break‐up of the Sino‐Korean Craton from Gondwana

Abstract

The Taebaeksan Basin is located in the mid‐eastern part of the southern Korean Peninsula and tectonically belonged to the Sino‐Korean Craton (SKC). It comprises largely the lower Paleozoic Joseon Supergroup and the upper Paleozoic Pyeongan Supergroup which are separated by a disconformity representing a 140 myr−long hiatus. This paper explores the early Paleozoic paleogeographical and tectonic evolution of the Taebaeksan Basin on the basis of updated stratigraphy, trilobite faunal assemblages, and detrital zircon U–Pb ages of the Joseon Supergroup. The Joseon Supergroup is a shallow marine siliciclastic‐carbonate succession ranging in age from the Cambrian Series 2 to Middle Ordovician. The Ongnyeobong Formation is the sole Upper Ordovician volcanic succession documented in the Taebaeksan Basin. It is suggested that in the early Paleozoic the Taebaeksan Basin was a part of an epeiric sea, the Joseon Sea, in east Gondwana. The Joseon Sea was the depositional site for lower Paleozoic successions of the SKC. Early Paleozoic sedimentation in the Joseon Sea commenced during the Cambrian Stage 3 (∼ 520 Ma) and ceased by the end of the Darriwilian (∼ 460 Ma). In the early Paleozoic, the SKC was located at the margin of east Gondwana and was separated from the South China Craton by an oceanic basin with incipient oceanic ridges, the Helan Trough. The spreading oceanic ridges and associated transform faults possibly promoted the uplift of the Joseon Sea, which resulted in cessation of sedimentation and break‐up of the SKC from core Gondwana by the end of the Ordovician.

Endolysins from Antarctic Pseudomonas Display Lysozyme Activity at Low Temperature

“…The high sequence identity of l ys177 and lys188 genes with P. koreensis D-26 sequences pinpoints that both sequences may have integrated in the common ancestor of the two strains before the break-up of the Sino-Korean Craton (which also includes the southern parts of the Korean Peninsula) from core Gondwana. The separation of South Korea from Gondwanaland started by the end of the Ordovician (nearly 400 mya) [ 42 ], long before the geographical isolation of the Antarctic continent from Gondwana and the formation of the Polar Front, which is a more recent geological event, dating over 60 mya ago [ 43 ].…”

Evolution of the Taebaeksan Basin, Korea: II, late Paleozoic sedimentation in a retroarc foreland basin and assembly of the proto‐Korean Peninsula

“…Lee et al, ), and a comparable disconformity can be traced into North China (Y. Wang, Zhou, Zhao, Ji, & Gao, ). The Joseon Supergroup is a shallow marine carbonate‐siliciclastic succession that ranges in age from Cambrian Series 2 to Middle Ordovician and is divided into the Taebaek, Yeongwol, and Mungyeong Groups (Choi, , in press). The Pyeongan Supergroup is a thick (1 700 m thick) clastic succession of marginal marine to non‐marine alluvial deposits that ranges in age from Late Carboniferous to Early Triassic (H. S. Lee & Chough, , ).…”

“…Two papers explore the Paleozoic evolution of the Taebaeksan Basin on the basis of updated information on the stratigraphy, faunal assemblages, sedimentation, and geochronology. Choi (in press) examines the early Paleozoic evolution of the Taebaeksan Basin, whilst the present paper deals with the late Paleozoic paleogeographical and tectonic evolution of the Taebaeksan Basin. The following principal questions on the evolution of the Taebaeksan Basin are addressed: How can the Paleozoic disconformity, 140 myr‐long hiatus, in the basin be explained in terms of tectonics? How did late Paleozoic sedimentation in the basin recommence at ~ 320 Ma or what was the tectonic setting for late Paleozoic sedimentation in the basin? What caused the termination of sedimentation in the basin at ~ 250 Ma? These questions are also applicable to those other Paleozoic sedimentary basins of the Sino‐Korean Craton that contain contemporaneous sedimentary deposits.…”

The Paleozoic evolution of the Korean Peninsula and Japan: An introduction

“…Korea has a complex geological history that extends deep into the Precambrian. Two papers in this volume provide an overview of the evolution of the Paleozoic succession in the Taebaeksan Basin (Choi, , ), which occupies the mid‐eastern part of the southern Korean Peninsula and is bounded to the northwest by the Gyeonggi Massif, to the southeast by the Yeongnam Massif, and to the southwest by the Chungcheong Basin or the Ogcheon Metamorphic Belt (Cho et al, ). The Taebaeksan Basin comprises the Cambrian (Series 2) to Middle Ordovician Joseon Supergroup and the Upper Carboniferous to lowermost Triassic Pyeongan Supergroup, these two supergroups being separated by a major disconformity that is also recognized in North China.…”

“…The Joseon Supergroup is the main record of lower Paleozoic strata on the Korean Peninsula, and its fossiliferous units suggest a North China paleocontinental affinity (Choi, ). Nevertheless, evidence from detrital zircons collected from the lower Cambrian Jangsan Formation and the younger Myobong Formation has contrasting provenance signatures, the earlier indicating a likely North China source, but the latter having a younger basement signature.…”