Marine Geology最新文献

{"title":"Global marine methane seepage: Spatiotemporal patterns and ocean current control","authors":"Xin Ni ,&nbsp;Xiuguo Liu ,&nbsp;Shilong Pang ,&nbsp;Yifei Dong ,&nbsp;Binbin Guo ,&nbsp;Yuhang Zhang ,&nbsp;Yang Wu ,&nbsp;Danyi Su ,&nbsp;Andi Xu ,&nbsp;Qinmeng Yuan ,&nbsp;Xuemin Wu ,&nbsp;Lin Yang ,&nbsp;Xiaoyu Wu ,&nbsp;Zhigang Wang ,&nbsp;Xi Xiao ,&nbsp;Qianyong Liang","doi":"10.1016/j.margeo.2025.107589","DOIUrl":"10.1016/j.margeo.2025.107589","url":null,"abstract":"<div><div>Marine sediments contain substantial methane reservoirs that play a significant role in global carbon cycling and climate systems. However, methane seepage is significantly influenced by ocean dynamics, with poorly understood spatiotemporal patterns. To investigate the spatiotemporal distribution patterns of methane seepage and the regulatory mechanisms of ocean currents, comprehensive coordinates and flux data of methane seepage from multiple marine regions worldwide were compiled. The spatial characteristics of methane seepage were quantified using nearest neighbor analysis and kernel density estimation, whereas the local and global autocorrelation between seepage activities, ocean currents, and sea surface temperatures were evaluated using Moran's index. Two clustering algorithms, spatiotemporal density-based spatial clustering of applications with noise (ST-DBSCAN) and ordering points to identify the clustering structure (OPTICS), were employed to identify the synergistic effects between temperature gradients and ocean current convergence zones through multiscale and hierarchical clustering approaches. Deep ocean currents may regulate methane seepage through multiple pathways: affecting hydrate stability via temperature gradients, altering local pressure fields through water level and flow velocity fluctuations, and influencing microbial geochemical processes through water mass exchange. The results indicate that methane seepage is most active in the circum-Pacific region and continental shelf areas, with approximately 42 % of seepage hotspots occurring in warm–cold current convergence zones. Mesoscale identification at 500 km reveals the influence of hydrodynamic processes such as eddies and fronts, whereas accessibility analysis quantitatively characterizes the hierarchical spatial associations of methane seepage, indicating enhanced seepage activity in warm current regions. These findings demonstrate the multiple control mechanisms of ocean currents on seafloor methane release through coupled temperature, pressure, and geochemical effects. This research provides a scientific foundation and a technical reference for quantitatively assessing the potential contribution of marine methane to global carbon cycling and identifying areas susceptible to elevated seepage.</div></div>","PeriodicalId":18229,"journal":{"name":"Marine Geology","volume":"487 ","pages":"Article 107589"},"PeriodicalIF":2.6,"publicationDate":"2025-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144154884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Inundation Signatures on Rocky Coastlines Global Database for coastal boulder deposits (ISROC-DB)","authors":"Andrew Kennedy ,&nbsp;Rónadh Cox ,&nbsp;Max Engel ,&nbsp;Emma Speyrer ,&nbsp;Annie Lau ,&nbsp;Nobuhito Mori","doi":"10.1016/j.margeo.2025.107581","DOIUrl":"10.1016/j.margeo.2025.107581","url":null,"abstract":"<div><div>Coastal boulder deposits are long-lived signatures of high-energy storm wave and tsunami inundation found on rocky and reefal coastlines worldwide. Although increasing numbers of research reports have been published on coastal boulder deposits, it has been difficult to compare studies from different areas because of a lack of standardised data and of quality-controlled datasets. This paper describes ISROC-DB, a new standardised database compiled from both published and unpublished data. There are two important parts: 1. Uniform standards to enable collation and intercomparison of coastal boulder deposits, with preformatted Excel files to enable convenient data entry; and 2. A freely accessible compiled database of coastal boulder deposit data. Both are published in downloadable permanent archives. Ongoing additions will further increase the database scope.</div></div>","PeriodicalId":18229,"journal":{"name":"Marine Geology","volume":"487 ","pages":"Article 107581"},"PeriodicalIF":2.6,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144072229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A landslide tsunami hazard assessment in the Makran Subduction Zone","authors":"Amin Rashidi ,&nbsp;Mohammad Mokhtari ,&nbsp;Katsuichiro Goda ,&nbsp;Mehdi Masoodi ,&nbsp;Parvaneh Faridi","doi":"10.1016/j.margeo.2025.107580","DOIUrl":"10.1016/j.margeo.2025.107580","url":null,"abstract":"<div><div>Seismic profiles have revealed historical submarine landslides within the western part of the Makran Subduction Zone (MSZ). A specific underwater landslide, identified off the coast of Chabahar, Iran, has been modeled to assess the potential hazard of the resultant tsunami waves in the MSZ. This submerged landslide near Chabahar has a volume of 7 km³. To evaluate the tsunami hazard, three scenarios have been developed: one static and two dynamic. According to the simulations<strong>,</strong> Chabahar experiences high waves, reaching heights of 5 m around its coast, with corresponding runup amplitudes of up to 10 m. Emphasizing the significance of dynamic considerations in understanding the tsunamigenesis of submarine landslides, the two dynamic scenarios differ primarily in landslide travel distance and, consequently, duration. The numerical modeling outcomes indicate that the dynamic scenario with the longer travel distance yields higher tsunami waves, reaching a maximum height of 15 m in the Oman Sea. Conversely, the other dynamic scenario generates waves with amplitudes similar to those produced in the static scenario. It takes about 15 min for the tsunami to reach Chabahar Station. Major ports in the region, including Chabahar, Jask, Muscat, and Sur, face elevated threats from the potential impact of this landslide-triggered tsunami. Notably, the shoreline of Pakistan exhibits a comparatively lower threat level in contrast to Iran and Oman. Looking ahead, future studies aim to compile a comprehensive database of tsunamigenic scenarios based on all potential landslides identified through seismic sections and bathymetry topology. This will enhance our understanding of the region's tsunami hazard from landslide-tsunamis.</div></div>","PeriodicalId":18229,"journal":{"name":"Marine Geology","volume":"487 ","pages":"Article 107580"},"PeriodicalIF":2.6,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144089359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The role of exposure on the vertical variation of mudflat sediment erodibility","authors":"Chuning Dong ,&nbsp;Yongping Chen ,&nbsp;Ian Townend ,&nbsp;Yiming Wu ,&nbsp;Zichao Guo ,&nbsp;Qin Jiang ,&nbsp;Giovanni Coco ,&nbsp;Karin R. Bryan ,&nbsp;Zeng Zhou","doi":"10.1016/j.margeo.2025.107579","DOIUrl":"10.1016/j.margeo.2025.107579","url":null,"abstract":"<div><div>Variations in meteorological conditions are known to influence the erodibility of sediments on tidal flats. However, there is limited understanding of how evaporation during exposure affects the stability of mudflats. In this study, we conducted field tests spanning 5 days in January 2021 and 14 days in August 2022 in the intertidal zone along the Yancheng coast in Jiangsu Province, China. We selected critical shear stress for erosion (τ_cr) and shear strength (SS) as erosion parameters, and analyzed the variations in hydrodynamic and meteorological parameters, and vertical sediment properties. Our results indicate that bed exposure in summer significantly enhances sediment stability, an effect that extends below the surface layer and even to deeper layers. As exposure duration increases, the differences with depth become more pronounced, leading to increased variability in τ_cr. This vertical gradient increases with exposure duration and atmospheric evaporation intensity, with both the values of vertical τ_cr and SS in summer showing a nearly 2 times increase compared to that in winter. The primary controlling parameter for changes in sediment erodibility during summer exposure is water content, while in winter, the mean grain size (D50) and salinity are more significant. The causal relationship between summer and winter exposure and resistance to vertical erosion of mudflats, shown in this study, underscores the need to pay greater attention to the seasonal influence of atmospheric processes on the spatial heterogeneity of sediments that arises from tidal exposure.</div></div>","PeriodicalId":18229,"journal":{"name":"Marine Geology","volume":"487 ","pages":"Article 107579"},"PeriodicalIF":2.6,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144098647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sources and transport-sedimentation processes of surficial detrital sediments in the southwest Arabian Sea: Insights from grain-size end-member component analysis","authors":"Dongyi Li,&nbsp;Yonghang Xu,&nbsp;Jian Chen,&nbsp;Yunhai Li,&nbsp;Liang Wang","doi":"10.1016/j.margeo.2025.107578","DOIUrl":"10.1016/j.margeo.2025.107578","url":null,"abstract":"<div><div>The Arabian Sea is an ideal region for exploring the sources and transport-sedimentation processes of surficial detrital sediments. Notably, grain-size end-member component (EMC) separation methods are powerful tools for this exploration. Through integration of this method with mineralogical and morphological characterization analyses, we identified four EMCs (EMC1-EMC4) suitable for the study area and elucidated the role of multiple forcings in controlling sources and transport-sedimentation processes. The findings revealed that variations in sources and diverse transport mechanisms govern the grain-size distribution patterns of surficial detrital sediments in the study area. The EMC1 ultrafine end-member is dominated by basalt weathering products from the Deccan Plateau and the west Indian Ocean, and is slightly influenced by aeolian dust from the interior of the Arabian Peninsula and northeast Africa. EMC2, EMC3, and EMC4 represent fine, coarse, and ultra-coarse fractions of aeolian dust primarily from different regions of the Arabian Peninsula, respectively. Monsoon circulation transports smectite-rich ultrafine sediments eastward across the Indian shelf, while Lower Circumpolar Deep Water (LCDW) carries them northward over long distances. Furthermore, the LCDW flows anticlockwise in the north Somali Basin, hindered by the Carlsberg Ridge, leading to the deposition of the ultrafine sediments it carries. Various wind systems interactions enable size-selective transport: fine EMCs traverse via mid-tropospheric pathways, whereas coarse EMCs are confined to the lower troposphere. The southwest monsoon facilitating the transport of fine EMC southward while impeding the transport-sedimentation of coarse EMCs.</div></div>","PeriodicalId":18229,"journal":{"name":"Marine Geology","volume":"487 ","pages":"Article 107578"},"PeriodicalIF":2.6,"publicationDate":"2025-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143942625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Submerged bedrock shore platforms, Orkney Islands, UK: A new record of significant, though chronologically uncertain sea-level change and coastal erosion","authors":"Dayton Dove ,&nbsp;Tom Bradwell ,&nbsp;Natasha L.M. Barlow","doi":"10.1016/j.margeo.2025.107577","DOIUrl":"10.1016/j.margeo.2025.107577","url":null,"abstract":"<div><div>Reconstructions of sea level change in NW Europe are primarily based on records of relative sea level (RSL) recovered from terrestrial environments, above modern sea level. This deficit in marine-based records results from the highly limited number of sea level indicators observed in modern submarine settings, as well as the often-limited absolute chronology information available. This sampling bias introduces significant uncertainty in former RSL predictions, negatively impacting efforts to accurately model ice-sheet histories and isostatic response. Here we present new seabed mapping data (i.e. high-resolution multibeam bathymetry) from northern Scotland to address this data gap. Encircling the Orkney Islands we identify an exceptional sequence of submerged terraces ranging from -5 to -95 m below modern sea level, carved in bedrock. We interpret these bedrock terraces as relict shore platforms, based on their spatial distribution and a range of geomorphological characteristics. Shore platform development was linked to contemporaneous landward coastline erosion and cliff formation, and each landform pair (i.e. terrace = shore platform and accompanying seacliff / escarpment) likely represents a single sea-level stillstand event of considerable duration (possibly millennia). These wide and well-preserved shore platforms attest to formation during multiple, separate periods of RSL stillstand, and we estimate that 5–7 RSL stillstands are recorded offshore Orkney. We discuss their potential age – spanning more than the last glacial cycle (i.e. Middle - Late Pleistocene) – and explore the wider implications for Quaternary coastal erosion and sea-level change in the region. This study shows how marine geological data and geomorphological analysis can be used to identify palaeo-sea-level indicators within a glacio-isostatically complex region. Despite a current lack of absolute chronological constraint, we believe these observations may provide crucial information towards understanding sea level change within the NW European region.</div></div>","PeriodicalId":18229,"journal":{"name":"Marine Geology","volume":"487 ","pages":"Article 107577"},"PeriodicalIF":2.6,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144070405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evidence for mixing of migrated hydrocarbons and indigenous organic matter in the Paleocene deepest core in IODP Expedition 378 Hole U1553D, Campbell Plateau, New Zealand","authors":"Simon C. George ,&nbsp;Lian Jiang ,&nbsp;Blanca Ausín ,&nbsp;Eleni Anagnostou ,&nbsp;Ann G. Dunlea ,&nbsp;Laurel B. Childress ,&nbsp;Ursula Röhl ,&nbsp;Deborah J. Thomas","doi":"10.1016/j.margeo.2025.107576","DOIUrl":"10.1016/j.margeo.2025.107576","url":null,"abstract":"<div><div>International Ocean Discovery Program (IODP) Expedition 378 recovered a continuous, &gt; 580 m thick Paleogene sedimentary sequence at Site U1553 on the Campbell Plateau, south of the South Island of New Zealand. Oil stain samples are rarely recovered during scientific ocean drilling, but one was recovered from the deepest Paleocene core in Hole U1553D (579.94 m CSF-A), associated with high amounts of methane and wet gases detected by on-board instrumentation, that led to drilling any deeper being prevented. This oil stain was analysed by gas chromatography–mass spectrometry and gas chromatography–triple quadrupole mass spectrometry, and compared with the indigenous Paleocene organic matter.</div><div>The <em>n</em>-alkane distribution of the oil stain sample is bimodal, suggesting mixing of a thermogenic migrated oil with a signal from the indigenous Paleocene sediments. This is confirmed by the ≥C₂₇ hopanoid and steroid biomarkers in the oil stain sample which are very similar to the immature Unit Vb early Paleocene sediments, including the presence of neohop-13(18)-enes, ββ hopanes, and βαα steranes. The C₁₀–C₂₀ aromatic compound distributions are in the molecular weight range where there is a mixed signal. The migrated thermogenic oil and gas were derived from a marine source rock containing a significant contribution from terrigenous and probably coniferous organic matter, deposited in a dysoxic depositional environment. Vertical migration of thermogenic oil and gas penetrated the early Paleocene sediments, but did not reach into the Eocene section due a significant permeability barrier associated with a middle–late Paleocene unconformity. Deeper drilling and geophysical investigation are required to understand the putative Cretaceous or older strata in this region.</div></div>","PeriodicalId":18229,"journal":{"name":"Marine Geology","volume":"486 ","pages":"Article 107576"},"PeriodicalIF":2.6,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143932036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morphology and Holocene activity of a high-latitude Canyon – Channel system: The proximal Lofoten Basin channel system (Norwegian Sea)","authors":"Hilde B. Amundsen ,&nbsp;Jan Sverre Laberg,&nbsp;Daniel H. Wiberg ,&nbsp;Tom Arne Rydningen,&nbsp;Amando P.E. Lasabuda ,&nbsp;Stine Bjordal-Olsen,&nbsp;Matthias Forwick","doi":"10.1016/j.margeo.2025.107574","DOIUrl":"10.1016/j.margeo.2025.107574","url":null,"abstract":"<div><div>Canyon – channel systems have the potential to be biological and marine litter “hotspots”, and they can act as important carbon sinks. However, knowledge about the modern (Holocene) activity of many of these systems remains poor. This includes the high-latitude Andøya Canyon - Lofoten Basin Channel located in the Norwegian Sea (∼69^oN). This study focuses on the proximal Lofoten Basin Channel and associated deposits (the Andøya Canyon is previously reported). The Lofoten Basin Channel includes two channel branches representing the canyon continuation beyond the foot of the continental slope, terminating in an area resembling a braidplain including braided channels, bars, as well as MTDs. Sediment cores included sandy turbidites. Based on their age and Ca/Fe ratios, we infer that the youngest sandy turbidites were deposited during the same event, suggesting that the event covered an area of c. 120 km × 20 km. Assuming an average thickness of ∼10 cm, this result in a volume of ∼0,24 km³ of terrigenous sand deposited in the basin over an area of ∼2400 km² sometime during the period from 3.7 to 2.4 kyrs BP. This equals a sand thickness of 4.8 m in the c. 50 km long and 1 km wide thalweg part of the Andøya Canyon, here considered to be the source area. The sand could derive from failure of sandy accumulations within the canyon and/or from sand piracy. Another aspect of this Holocene turbidite event is that it represented a substantial export of inorganic carbon into the deep sea which in this way got buried, representing a carbon sink removing carbon from the carbon cycle (a carbon draw-down effect). These results shows that the canyon is a potential source and route for sediments that may cover ∼2400 km² of the sea floor, large deep-sea areas that also represent carbon sinks so far not well accounted for.</div></div>","PeriodicalId":18229,"journal":{"name":"Marine Geology","volume":"486 ","pages":"Article 107574"},"PeriodicalIF":2.6,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143902161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Testing spatial interpolation methods for deep-time organic carbon burial in epicontinental seas by taking Sunda Shelf as an example","authors":"Yida Yang ,&nbsp;Pengfei Ma ,&nbsp;Xiumian Hu ,&nbsp;Yuan Gao ,&nbsp;Chengshan Wang","doi":"10.1016/j.margeo.2025.107566","DOIUrl":"10.1016/j.margeo.2025.107566","url":null,"abstract":"<div><div>Quantifying the burial of organic carbon (OC) in epicontinental seas is crucial for understanding its role in regulating global long-term carbon cycle and climate. Utilizing spatial interpolation methods, prior works have quantified OC burial globally or regionally based on limited, unevenly distributed measurements. However, there remains a notable lack of comparative studies and assessments regarding their applicability and uncertainty in deep-time research. Taking the middle Miocene Sunda Shelf OC burial estimation as an example, four popular spatial interpolation methods are assessed quantitatively and qualitatively, including Thiessen polygons, Inverse Distance Weighting (IDW), Ordinary Kriging (OK) and Random Forests (RF). Based on quantitative and qualitative evaluation, the data-driven RF method demonstrates superior performance due to fewer assumptions, effectively capturing nonlinear relationships and complex spatial patterns in heterogeneous, non-Gaussian deep-time data, and demonstrating strong generalizability and robustness. High-resolution RF-based reassessment reveals significant spatial-temporal heterogeneity of OC burial on the Sunda Shelf between the Miocene Climatic Optimum (MCO) and Middle Miocene Climate Transition (MMCT). Although the overall OC burial and sediment accumulation rates (SAR) increase during the MMCT, notable spatial discrepancies emerge, with OC burial rates elevated near basin margins but decreased in distal regions. These variations primarily reflect the combined influences of eustatic sea-level fall and enhanced terrigenous input, highlighting the complex interplay of factors modulating OC burial efficiency. Machine learning methods such as RF prove highly effective in handling deep-time spatial data, but their application should be adapted to specific objectives, geological conditions, and data characteristics.</div></div>","PeriodicalId":18229,"journal":{"name":"Marine Geology","volume":"486 ","pages":"Article 107566"},"PeriodicalIF":2.6,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143886871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Longitudinal transport of net suspended sediment in the river-dominated Modaomen Estuary of the Pearl River: Effects of river, tide, and mouth bar","authors":"Xinran Li ,&nbsp;Feng Liu ,&nbsp;Hao Zou ,&nbsp;Chao Tan ,&nbsp;Jie Huang ,&nbsp;Sihao Mo ,&nbsp;Haiwei Li ,&nbsp;Rongyao Xie ,&nbsp;Heng Wang","doi":"10.1016/j.margeo.2025.107575","DOIUrl":"10.1016/j.margeo.2025.107575","url":null,"abstract":"<div><div>The suspended sediment dynamics in estuaries are strongly affected by the interaction of rivers, tides, and morphological factors. However, little is known about the combined impact of these driving factors on longitudinal net sediment transport. A field investigation of current velocity, salinity, and suspended sediment concentration (SSC) was conducted in the Modaomen Estuary of the Pearl River. Hydrological data were simultaneously measured at three mooring stations in the longitudinal direction on July 31, and August 8, 2017, covering a neap tide and a spring tide. Net suspended sediment transport patterns were also analyzed. Current velocity, SSC, and salinity exhibited spatial and temporal variations during the spring–neap tides. Seaward net sediment transport was dominant during the observation period and, vertically, double patterns of net sediment transport inside and outside the mouth bar appeared to occur in the longitudinal profile. The net sediment flux can be divided into three major components—advection sediment transport, tidal-pumping, and vertical circulation. Of these, seaward sediment advection was the dominant component, which generally conformed to the dynamic characteristics in a river-dominated estuary. Salinity intrusion into the bottom layer caused stratification, inhibited vertical diffusion, and enhanced sediment settling, resulting in an elevated SSC in the bottom layer at the mouth bar. Eulerian residual flow primarily contributed to the seaward advection transport. Tidal asymmetries during the ebb–flood tidal cycle enhanced tidal-pumping sediment transport, and the main driving factor, SSC asymmetry, corresponded well with sediment flux. The mouth bar exerted a significant morphological effect on salinity intrusion and promoted longitudinal estuarine circulation, thus affecting longitudinal sediment transport. Our results contribute to a better understanding of the underlying mechanism of suspended sediment transport in complex dynamic environments as well as the feedback between the hydrodynamic structure and morphology in estuaries, facilitating the development of evidence-based guidelines for estuarine and coastal engineering and management.</div></div>","PeriodicalId":18229,"journal":{"name":"Marine Geology","volume":"486 ","pages":"Article 107575"},"PeriodicalIF":2.6,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143906657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}