Marine Geology最新文献

{"title":"A recently identified mass-transport deposit stack in the Guaymas Basin, Gulf of California (México), and its implication in the basin tectonics","authors":"A. Piña ,&nbsp;J. Stock ,&nbsp;D. Lizarralde ,&nbsp;S. Hart ,&nbsp;K. Marsaglia ,&nbsp;C. Gallegos-Castillo ,&nbsp;C. Berndt ,&nbsp;A. González-Fernández ,&nbsp;C. Mortera-Gutiérrez ,&nbsp;A. Martín-Barajas","doi":"10.1016/j.margeo.2025.107592","DOIUrl":"10.1016/j.margeo.2025.107592","url":null,"abstract":"<div><div>A large mass transport deposit (MTD) stack has been identified in the Guaymas Basin using seventeen high-resolution seismic reflection profiles and sediment core analysis. Guaymas Basin is a young, marginal basin characterized by active seafloor spreading in the central Gulf of California, Mexico. The large stack includes five distinct MTD units of variable thickness, area, and volume, characterized by a predominantly transparent seismic reflection facies with small sections of laterally discontinuous reflectors and bumpy upper and erosional lower surfaces. Based on analysis of sediment cores from Site U1551A from International Ocean Discovery Program Expedition 385, we define MTD lithofacies and use sand provenance to infer that the MTD stack originated from the Yaqui Delta region of the Sonoran margin, transporting material to the south-west. We suggest that a combination of high sedimentation rates and active tectonics contributed to the MTD events. ‘Flower structures’ observed in margin-crossing profiles indicate that the MTD stack buried a part of the transform fault separating the Guaymas Basin and the continental Sonoran margin. Seismic reflection interpretations suggest that part of the MTD stack filled the southern graben applying local stresses that drove a change of the sediment surface expression of plate spreading in the sediment-filled basin. In response to the MTD emplacement and the southern graben fill, an additional northern seafloor graben in the Guaymas Basin developed. Our results contribute to the understanding of the interactions among high sedimentation rates, continental slope stability, and active tectonics; and the influence of those interactions on the surface expression of plate spreading in the Guaymas Basin.</div></div>","PeriodicalId":18229,"journal":{"name":"Marine Geology","volume":"488 ","pages":"Article 107592"},"PeriodicalIF":2.6,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144322793","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":"Impacts of climate change on the morphodynamics of embayed beaches along the Central West Coast of India","authors":"Puneet Kumar Mishra ,&nbsp;R. Mani Murali ,&nbsp;Deepika Dwivedi ,&nbsp;S.K. Ariful Hossain ,&nbsp;S. Santhosh Kumar ,&nbsp;Shincy Francis ,&nbsp;Richa Rai","doi":"10.1016/j.margeo.2025.107590","DOIUrl":"10.1016/j.margeo.2025.107590","url":null,"abstract":"<div><div>This study investigates the morphodynamics and climatic influences on twenty-seven embayed beaches along the central west coast of India utilizing a comprehensive framework that combines in-situ field observations and remote sensing. These coastal features were classified for the first time using an embayment morphometric parameter (γe) derived from the embayment area (Ae) and indentation (a). This method enabled the categorization of the embayments into three distinct classes - Class 1 (open/exposed), Class 2 (semi-exposed), and Class 3 (Semi-closed/sheltered). Field measurements of beach profiles were conducted for sixteen accessible embayed beaches, focusing on seasonal and annual volumetric changes. The results showed a significant reduction in beach volume from February to September, likely caused by strong monsoonal waves, with partial recovery observed from September to February. To study long-term changes, we analyzed changes in area over three decades (1990–2023) using satellite images. This analysis revealed a maximum erosion of 81.72 m at Mirya and maximum accretion of 62.5 m at Undi, while Net Shoreline Movement (NSM) trends reveal that eight embayments, including Palshet, Hedavi, and Vengurla, are undergoing critical shoreline retreat. Various climate factors, including rising sea levels, increased frequency of cyclones, wave power, and swells, were analyzed to track the causes. The results indicated an increase in regional sea levels, cyclone activity, and wave power, which corresponded with the observed erosion patterns along the central west coast of India. Anthropogenic impacts were also noted,the construction of breakwaters and jetties has caused significant alterations. This study highlights, how human interventions can disrupt natural coastal processes. A key finding of the study is that embayments, which appear stable on seasonal and annual timescales, are dynamic and unstable over the decadal scale.</div></div>","PeriodicalId":18229,"journal":{"name":"Marine Geology","volume":"487 ","pages":"Article 107590"},"PeriodicalIF":2.6,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144204095","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":"Estimation of turbidite source area in late Pleistocene to Holocene around Kikai Island based on mineral and biogenic calcium carbonate composition","authors":"Ryo Nakanishi ,&nbsp;Ayumi Maeda ,&nbsp;Atsuko Amano ,&nbsp;Juichiro Ashi ,&nbsp;Asuka Yamaguchi ,&nbsp;Yusuke Yokoyama ,&nbsp;Yosuke Miyairi","doi":"10.1016/j.margeo.2025.107593","DOIUrl":"10.1016/j.margeo.2025.107593","url":null,"abstract":"<div><div>Identifying the initial location of a turbidity current can help reveal a paleogeography, potential petroleum reservoir rocks, and a paleoseismic history. Therefore, a method for estimating the source area of turbidites is crucial. This study estimates the source area of turbidites using marine core sediments and surface sediments obtained around Kikai Island, located in the central Ryukyu Arc. We focus especially on mineral composition, variations of grain-size distribution and microfossil assemblages to estimate the water depth and hinterland geology of the source sand. Calcareous turbidites exhibiting normal grading or laminated structures were identified in the marine core at the fore-arc slope. We compare the calcium carbonate mineral compositions of these calcareous turbidites with those of surface sediments by X-ray diffraction (XRD) analysis. The proportion of aragonite and magnesium calcite, as opposed to calcite, decreases with increasing water depth, corresponding to the habitat of foraminifera and pteropods. A regression equation was obtained from the calcium carbonate mineral ratio and water depth. The predicted water depth of the turbidite source was equivalent to that based on benthic/planktonic foraminiferal ratios. In addition, principal component analysis of XRD results and grain size analysis spatially constrained the source area of turbidites by comparison with surface sediments in the hinterland geology. Since turbidite deposition was limited to 14.7–9.7 ka, we interpret that increased sediment supply resulting from coral-reef drowning during rapid sea-level rise, and calcareous sand beds were unstable and transported by turbidity currents. The method developed in this study provides a framework for estimating the supply source of turbidites and is expected to be used in paleoseismic studies and petroleum reservoir evaluation.</div></div>","PeriodicalId":18229,"journal":{"name":"Marine Geology","volume":"487 ","pages":"Article 107593"},"PeriodicalIF":2.6,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144204094","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":"Controls of paleosedimentary environments and anthropogenic activities on coastal groundwater salinization: A case study of Laizhou Bay, China","authors":"Zhen Cui ,&nbsp;Guangquan Chen ,&nbsp;Xin Shan ,&nbsp;Haitao Zhang ,&nbsp;Qingjie Zhou ,&nbsp;Tengfei Fu ,&nbsp;Hongjun Yu ,&nbsp;Xingyong Xu ,&nbsp;Shenliang Chen","doi":"10.1016/j.margeo.2025.107594","DOIUrl":"10.1016/j.margeo.2025.107594","url":null,"abstract":"<div><div>Groundwater salinization presents a substantial environmental challenge for coastal regions globally, particularly along the southern shore of Laizhou Bay. The processes contributing to groundwater salinization are intricate and involve interactions between natural factors and human activities. This study examines the mechanisms underlying groundwater salinization at varying depths in the southern Laizhou Bay area, with a particular emphasis on the effects of extensive groundwater extraction. Excessive groundwater extraction has intensified salinization by altering hydraulic gradients and promoting seawater intrusion. Utilizing sediment and pore water samples from two boreholes (SG100 and WF80) alongside shallow seismic data, we identified that sedimentary strata consisting of alternating marine and terrestrial deposits, formed during multiple transgressive events since the Late Pleistocene, are a significant source of salinity. Paleoenvironmental reconstructions based on grain size analysis, combined with Cl/Br ratios and stable isotope analysis, indicated that modern seawater intrusion is a primary driver of shallow groundwater salinization. In contrast, variations in deep groundwater salinity reflect differing paleoenvironmental recharge conditions. Ancient riverbed sediments exhibit high permeability, providing an efficient pathway for the transport of water and salts from upstream freshwater bodies. This process facilitates the dilution within the aquifer, leading to the formation of low-salinity groundwater. In contrast, the low permeability of floodplain sediments significantly restricts the renewal capacity of water bodies. As a result, the saline water layer maintains a high salinity state over extended periods due to the combined effects of evaporation and limited recharge. Notably, offshore freshwater was detected within ancient river channel deposits. These findings underscore the intricate interplay between sedimentary evolution and anthropogenic activities in influencing groundwater salinization, highlighting the necessity for scientifically informed, water-type-specific management strategies.</div></div>","PeriodicalId":18229,"journal":{"name":"Marine Geology","volume":"487 ","pages":"Article 107594"},"PeriodicalIF":2.6,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144196389","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":"Particulate organic carbon dynamics off the Yellow River Estuary revealed by in-situ hydrodynamics and carbon isotopes","authors":"Taian Lu ,&nbsp;Thomas S. Bianchi ,&nbsp;Naishuang Bi ,&nbsp;Xiao Wu ,&nbsp;Shuai Cong ,&nbsp;Jinya Xu ,&nbsp;Xiaoyan Ning ,&nbsp;Houjie Wang","doi":"10.1016/j.margeo.2025.107591","DOIUrl":"10.1016/j.margeo.2025.107591","url":null,"abstract":"<div><div>The Land-to-Ocean-Aquatic-Continuum (LOAC) is a key component in global carbon cycle and budget. Delivery of organic carbon (OC) along the LOAC is impacted by coastal hydrodynamics on a variety of spatial-temporal scales. Here we provide a coupled analysis of suspended particulate OC (POC) transport and hydrodynamics in the Yellow River Estuary. Pre-aged soil POC has become the dominant component (40–50 %) in the river-estuary continuum during the flood season. Petrogenic POC, with high proportion in the river (31 %), experienced drastic deposition off the estuary due to entrapment by shear fronts and estuarine circulation, decreasing to 19–23 %. The terrestrial OC was mainly exported offshore along with the seaward extension of river plume during ebb tide, while could be pushed landward by intruding seawaters during flood tide. When the tidal effects were removed, the first-order net POC residual flux was ∼19 g/m/s in seaward direction in the near-field plume, with dominance of pre-aged soil POC at ∼8 g/m/s and petrogenic POC at ∼6 g/m/s; on the contrary, POC fluxes displayed a landward direction and decreased by two orders of magnitude in the far-field plume. Trapped by shear fronts and estuarine circulation, POC was mostly limited and temporally preserved off the river mouth during the flood season. These findings suggest that intra-tidal estuarine hydrodynamics can further influence the sources, composition, and transport of terrestrial POC, playing a significant role in regulating carbon cycling along the Land-to-Ocean-Aquatic-Continuum.</div></div>","PeriodicalId":18229,"journal":{"name":"Marine Geology","volume":"487 ","pages":"Article 107591"},"PeriodicalIF":2.6,"publicationDate":"2025-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144196386","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":"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}