Late Quaternary Environmental Changes of the Hwajinpo and Songjiho Lagoons on the Eastern Coast of Korea

Holocene salinity fluctuations of the East Korean lagoon related to sea level and precipitation changes

“…In the southern part of the East Korean coast, the sea level rose rapidly from −10 m at 7000 years BP to around the present level at 6000 years BP (Jo, ; Pirazzoli, ). A lacustrine terrace as an erosional landform about 1.6 m above mean sea level located 60 km north of the coring site provides evidence of highstand sea level conditions about 1.6 m above the present sea level ca 6400–5700 years BP (Yum et al, , ). Moreover, many areas along the Japanese coast were characterized by a sea level maximum at around 6000 cal.…”

“…This suggests that the high level of salinity during the mid-Holocene period was derived from seawater inflow. This kind of salinity change is common among the lagoons along the East Korean coast (Yum et al, 2015) (Figure 4). The changes in grain size and bottom oxygen condition suggested by core lithology indicate that the transgression-regression cycle (T-R diagram: Figure 4) induced these common salinity changes (Yum et al, 2015).…”

“…This kind of salinity change is common among the lagoons along the East Korean coast (Yum et al, 2015) (Figure 4). The changes in grain size and bottom oxygen condition suggested by core lithology indicate that the transgression-regression cycle (T-R diagram: Figure 4) induced these common salinity changes (Yum et al, 2015). In fact, the high-salinity periods in the Maeho Lagoon coincide well with periods of high sea levels in Korean and Japanese coastal areas (Cho et al, 2017;Jo, 1980;Nakamura, 2006;Ota, Umetsu, & Matsushima, 1990;Pirazzoli, 1991;Tanigawa, Hyodo, & Sata, 2013;Yum et al, 2004, and references therein).…”

“…The values of MS and DBD show multicentennial timescale cyclic variation in the laminated layers of core PMR-2 (Figure 5d,e). Chronological correlations between the relative abundances of marine and marine-brackish diatom taxa in core PMR-2; relative (Modified from Jo, 1980) and absolute sea levels (Yum et al, 2015) on the East Korean Coast and in the San'in Region, Japan (Modified from Nakamura, 2005); and transgression-regression (TR) diagrams in the Hwajinpo (60 km away from the Maeho lagoon, dashed gray line) and Songjiho (40 km away, solid gray line) lagoons (Yum et al, 2015). Solid line, summarized sea level curve; dashed line, sea level deduced from grain size (Jo, 1980); bold lines, absolute sea level determined by the initial time of transgression events in the Hwajinpo and Songjiho Lagoons and erosional landforms around these lagoons (Yum et al, 2015) Fluctuations MS and DBD values coincide well with the turnover in diatom species (Figure 5f-k).…”

A Study on Analysis of Freshwater-saltwater Interface in the Aquifer around Hwajinpo Lagoon on the Eastern Coast of Korea

“…서해안과 남해안 지역 의 경우에는 해안선이 복잡하고 조석간만의 차가 최대 6m에 달하기 때문에 해수침투가 일어날 가능성이 크며, 지하저장시설의 개발 등으로 인해 다양한 연구가 진행되 었다 (Lee et al, 2003;Lee et al, 2007;Lim et al, 2013;Lee et al, 2015;Kim et al, 2018;Kwon et al, 2020). Yum et al, 2002). (Yum et al, 2004).…”