The sedimentary source, planform stability and shore normal morphological change of the Xichong beach on the southern coast of the Dapeng Peninsula of Shenzhen, Guangdong Province, China

The Use of Heavy Minerals in the Investigation of Barrier-Lagoon Coasts Development in Dapeng Peninsula, China

“…Lu et al [21] also obtained a 14 C age of 2080 ± 95 a BP from the beachrock in the same section of Xichong Beach. However, the outcrop of the same beachrock was found by Zhang et al [22] about 30 years later, at a level of 2.08 m higher than the local mean high level (MHW) and 1.34 m higher than the local mean higher high water (MHHW), while the local mean tidal range is not more than 1m [23], indicating a possible higher sea level in the Holocene period. Using thermoluminescence (TL) dating technique, Lu et al [21] showed that the coastal dune ridges at the top of the Xichong barrier were younger, i.e., shoreward from 2.7 to 1.4 ka BP.…”

“…Easterly winds prevail throughout the year and constantly blow from the southeast in summer and the northeast in winter. September is the most active month for tropical cyclones and typhoons, producing abundant rain fall [22]. In the sea of the Dapeng Bay, west of the peninsula, the annual maximum wave height is 2 m, and the annual mean wave height is only 0.34 m. Waves from the south are predominant, occupying about 19.23% of the year.…”

“…The bedrock around Xichong Bay is composed of Mesozoic granitic rocks and Paleozoic sedimentary rocks [25]. Before reaching the western side of Xichong Bay, the Xichong River flows across an area where the Upper Jurassic medium-grained porphyritic biotite granite and Lower Cretaceous biotite (monzonitic) granite are widely exposed [22,25]. The rocks that form the headlands on both sides of Xichong Bay are Devonian sedimentary [25].…”

“…The rocks that form the headlands on both sides of Xichong Bay are Devonian sedimentary [25]. The Dongchong River begins in an area composed of Mesozoic granites and Devonian sedimentary rocks, and then cuts through an area occupied by Cretaceous and Jurassic volcanic rocks, known as Qiniang Mountain volcanic system, before entering Dongchong Bay [22,25].…”

“…Using thermoluminescence (TL) dating technique, Lu et al [21] showed that the coastal dune ridges at the top of the Xichong barrier were younger, i.e., shoreward from 2.7 to 1.4 ka BP. Zhang et al [22] discovered that the sand from streams is the main sedimentary source for the modern beaches of Dongchong and Xichong Bays, based on the analysis of heavy minerals in the sediments of the modern beaches and inland rivers that flow into the bays. However, the sediment source of modern beaches can only reflect the current conditions of coastal dynamics.…”