Geotechnical properties of sediment cores from the southeastern yellow sea: Effects of depositional processes

Abstract

Geotechnical properties of 20 scattered sediment cores from the southeastern Yellow Sea reveal that sediments contain certain common characteristics indicative of depositional processes. Silty and sandy sediments off the Taean Peninsula are largely consolidated and extensively bioturbated. Further seaward sandy sediments are consolidated in which sands are well sorted and shell fragments are scattered. In contrast, muddy sediments near the mouth of the Keum River are high in water and clay contents and low in shear strength. Water content increases with depth, but shear strength decreases. Fine sediments derived from the Keum River are restricted nearshore along the coast. Off the southwestern coast off Mokpo, sediments consist of wellsorted silty layers and laminae with various degrees of bioturbation, which result in depth variations in water content and shear strength. Here, individual silty layers and laminae support the evidence of resuspension and deposition by strong tidal (and nearshore) currents. The laminae are thinner and more discrete towards deeper water with more extensive bioturbation. In the central depression of the Yellow Sea, water-and clay-rich surface sediments are underconsolidated, but underlying silt-dominant sediments are normally consolidated. These sediments are high in calcium carbonate content, suggestive of the Huanghe River source.

Quantified sensitivity of small lake sediments to record historic earthquakes: Implications for paleoseismology

“…Grain size appears particularly important for slope stability because it determines porosity‐controlled properties (e.g., bulk density, water content, and void ratio) [ Baraza and Ercilla , ] and notably acts on the shear strengths [e.g., Ai et al ., , and references therein]. For instance, undrained shear strength can be significantly reduced by small increases in sand content [ Lee et al ., ]. Moreover, the internal friction angle decreases when clay content increases, reflecting the low mobilized friction between fine particles [ Dhouib et al ., ].…”

Stability of sediments on the Ulleung basin slope

“…Water content as well as porosity and void ratio was measured at the same intervals. Atterberg limits (liquid and plastic limits) were determined at 20 to 40 cm intervals in each core, following the American Standard for Testing Materials (ASTM) methods., Detailed procedures for geotechnical properties can be found elsewhere (Lee et al 1987). Calcium carbonate content was gasometrically measured using Bernard calcimeter, organic matter by combustion loss at 10 cm intervals in selected cores.…”

Surface currents from hourly variations of suspended particulate matter from Geostationary Ocean Color Imager data

“…The Yellow Sea is characterized by high turbid water, especially along the southwestern coast of Korea, as shown in Figure 1. This turbid water is well known to be induced by strong tidal currents at the coastal region due to its shallow bathymetry (Lee et al 1987;Lee and Chough 1989). A significant amount of land-derived materials flows into the shelf from rivers in the East Asian region and is dispersed in the form of SPM by the strong tidal currents.…”