An occurrence of inclined heterolithic stratification (IHS) is described from a tidal point bar in a 40-m-deep distributary of the macrotidal (tidal range 3.6-7.8 m), Han River delta, Korea. The channel bank demonstrates a convex-upward profile with intermittent presence of wave-formed scarps and terraces near the low-water level. The vertical succession of IHS is approximately 25 m thick and dips into the channel with angles reaching 14؇. The IHS overlies 15 m of trough cross-bedded sand deposited in the channel thalweg and lower point bar. Even though the channel as a whole is ebb dominated, the preserved cross bedding is predominantly flood directed because the mutually evasive nature of the ebb and flood currents causes the pointbar surface to be flood dominated. This pattern may be a common feature of tidal point bars. The IHS itself consists of interstratified fine sand, sandy silt, and silt with an upward-fining textural trend. Tidal rhythmites are well developed in the middle and upper intertidal zone, and may also be present in the subtidal zone, but are poorly developed near the low-water level because of wave action. Seasonal discharge variations of the Han River are not obvious in the deposits, because the large size, distal location, and energetic tidal environment of the studied channel reduces the impact of river-stage fluctuations. Despite the moderate salinity levels, bioturbation is rare, except in the upper intertidal zone, because of the rapid sedimentation and energetic conditions.
deposits making up >20 % of the drilled upper 220 m of the ca. 550-m-thick sedimentary fill. During basin development, extension and subsidence alternated with compressional periods, particularly between ~340 and 290 ka and sometime before ~14 ka, when normal fault movements reversed and gentle anticlines formed as a result of inversion. The ~14 ka event was accompanied by widespread uplift and erosion along the northeastern margin of the lake, and substantial erosion took place on the crests of the folds. A series of closely spaced eruptions of Süphan volcano occurred synchronously suggesting a causal relationship. Compression is still prevalent inside and around Lake Van as evidenced by recent faults offsetting the lake floor and by recent devastating earthquakes along their onshore continuations. New, high-resolution bathymetry data from Lake Van reveal the morphology of the Northern Ridge and provide strong evidence for ongoing transpression on a dextral strike-slip fault as documented by the occurrence of several pop-up structures along the ridge.
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