Contents lists available at ScienceDirect Estuarine, Coastal and Shelf Science journal homepage: www.elsevier.com/locate/ecss Textures, provenances and structures of sediment in the inner shelf south of Shandong Peninsula, western South Yellow Sea Gang Hu a,b,c,* , Kehui Xu d,e , Peter D. Clift c,e , Yong Zhang a,b,** , Yuting Li c , Jiandong Qiu b , Xianghuai Kong b , Shipu Bi b a Lab for Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China b Qingdao Institute of Marine Geology, China Geological Survey, Qingdao, 266071, China c Department of Geology and Geophysics, Louisiana State University, Baton Rouge, LA, 70803, USA d Department of Oceanography and Coastal Sciences, Louisiana State University, Baton Rouge, LA, 70803, USA e Coastal Studies Institute, Louisiana State University, Baton Rouge, LA, 70803, USA ARTICLE INFO Keywords: Sedimentary structure Provenance Surficial sediment Southern Yellow Sea Shandong Peninsula ABSTRACT Although many studies have been performed on the mud wedge in the distal part of the Yellow River subaqueous delta, little is known about the southwestern terminus of the Yellow River mud wedge in the inner shelf of the Southern Yellow Sea (SYS). We use ∼3000 km of high-resolution subbottom seismic profiles, 147 surficial se- diment samples, as well as 30 fluvial sediment samples to study sediment textures, provenance and structures in the inner shelf in western SYS. Our results show that sediment in the inner shelf south of Shandong Peninsula can be categorized into multiple types, including sand, silt, sandy silt, muddy sand, mud, gravel mud and others. About 60% of the study area is covered by silt and sandy silt. Assuming a finer texture of sediment from Yellow River and a relatively coarser one for sediment from local small rivers, our results reveal at least two contrasting sediment sources. East of the Laoshantou Headland, on the southern coast of the peninsula, the sediment is mainly from the Yellow River. Holocene sediment deposition reaches about 15 m thickness in water depths of ∼10 m. The homogeneous surficial sediment pattern is mainly controlled by the Yellow Sea Coastal Current, the Yellow Sea Warm Current, as well as local currents. However, west of Laoshantou Headland, sediment from local small rivers draining the peninsula plays a more important role. Over there the Holocene mud wedge is no more than 5-m thick, and is re-worked by strong tides and longshore currents. The seaward extension of Laoshantou Headland the southern peninsula seems to act as an effective sediment trap, aiding the accumulation of sediment carried by longshore currents. This new study delineates the western boundary of Yellow River subaqueous delta and helps better quantify sediment budget in the Yellow Sea. It also shed light on the sedimentation interplay of large rivers with local small rivers on many epicontinental shelves and passive margins around the world. 1. Introduction The distribution of marine sediments is generally controlled by the source and depositional environment. Sediment grain sizes and types are important for the understanding of sediment transport and de- positional mechanisms in the modern environment, as well as for ex- plaining depositional processes and sediment dynamics over geological time scales (Gao and Collins, 2014). In this study we investigate the terrigenous sediment that forms a depositional system in the Southern Yellow Sea (SYS) under the influence of complex current systems. Previous studies were conducted on the mud depositional system in the Northern Yellow Sea (NYS) and central SYS regions, focusing on the sediment origin, paleoclimate, and transport mechanisms (Milliman et al., 1987; Cheng and Gao, 2000; Shi et al., 2002; Liu et al., 2002, 2007, 2004; Yang and Liu, 2007; Wang, 2009). Yang and Liu (2007), for instance, reported a large and elongated mud belt in the distal part of the Yellow River subaqueous delta, wrapping along the coast of Shan- dong Peninsula (Fig. 1). Line spacings of seismic profiles used by Yang and Liu (2007), however, were on the scale of 10 s km which makes it challenging to delineate the exact boundary of the Yellow River sub- aqueous delta and its detailed structure. Little research has been carried out concerning mud deposition on the inner shelf south of the Shandong Peninsula (Zhao et al., 1991). The Yellow River is the second largest river of the world in terms of sediment loads. Over the last several https://doi.org/10.1016/j.ecss.2018.07.018 Received 14 November 2017; Received in revised form 2 July 2018; Accepted 11 July 2018 * Corresponding author. Lab for Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China. ** Corresponding author. Lab for Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China. E-mail addresses: Hg_jinan@163.com (G. Hu), qimgzy@163.com (Y. Zhang). Estuarine, Coastal and Shelf Science 212 (2018) 153–163 0272-7714/ © 2018 Published by Elsevier Ltd. T