Deep-sea Research Part Ii-topical Studies in Oceanography最新文献

{"title":"Dynamic impact of transiting weather systems on coastal currents in the northern Gulf of Mexico","authors":"Chunyan Li ,&nbsp;Alex Sheremet ,&nbsp;Wei Huang ,&nbsp;Padmanava Dash ,&nbsp;Ankita Katkar ,&nbsp;Mohammad Nabi Allahdadi ,&nbsp;Nazanin Chaichitehrani ,&nbsp;Charles M. Bachmann ,&nbsp;Victor H. Rivera-Monroy","doi":"10.1016/j.dsr2.2024.105395","DOIUrl":"https://doi.org/10.1016/j.dsr2.2024.105395","url":null,"abstract":"<div><p>Moving weather systems determine the history of wind variations with patterns as the systems transit through the ocean. These weather systems are integrated entities that can provide a system level perspective. A vessel-based survey repeatedly occupying a 30-km transect 12 times in 36 h provided non-aliased measurements of velocity field that showed how the along-shelf transport varied by more than three-fold in response to a transiting high-pressure weather system following an atmospheric cold front. To further illustrate the impact of different weather systems, we analyzed time series data from moored ADCPs, which showed influence on the velocity field from infrequent summertime cold fronts and remote hurricanes moving through the region, one on the west and the other on the east of the study site. Rotary spectrum analysis showed that the flow field rotated mostly clockwise with a smaller but non-negligible counterclockwise component, consistent with near inertial oscillations mixed with weak tidal currents. A theoretical model is presented by a Laplace transform and a general relationship between the velocity field and forcing functions is obtained, which shows that the contributions to the rotary velocity field from various forcing functions are through mathematical convolutions between the forcing functions and the complex frictional-rotary inertial function (CFRIF). These convolutions include an integrated effect of history of the forcing. CFRIF is effectively a frictional rotary filter that favors inertial oscillations. The wind-stress induced velocity field over a few days is computed and it shows significant variations after the passage of a cold front, with a magnitude consistent with observations. The wind-stress induced velocity is a few times greater than the density driven flow during the ship-based observations. The weather systems passing through the region can impact coastal currents causing a great variability over short time scales.</p></div>","PeriodicalId":11120,"journal":{"name":"Deep-sea Research Part Ii-topical Studies in Oceanography","volume":"216 ","pages":"Article 105395"},"PeriodicalIF":3.0,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141423515","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":"Impact of a fresh-core mesoscale eddy in modulating oceanic response to a Madden-Julian Oscillation","authors":"Marina V.C. Azaneu ,&nbsp;Adrian J. Matthews ,&nbsp;Karen J. Heywood ,&nbsp;Rob A. Hall ,&nbsp;Dariusz B. Baranowski","doi":"10.1016/j.dsr2.2024.105396","DOIUrl":"https://doi.org/10.1016/j.dsr2.2024.105396","url":null,"abstract":"<div><p>Theories of ocean–atmosphere interaction during a Madden–Julian Oscillation (MJO) are generally based on a thermodynamic model with surface fluxes dictating changes in sea surface temperature. Evidence from a two month ocean glider deployment in early 2019 in the southeast Indian Ocean suggests the impact of mesoscale dynamics on upper-ocean stratification likely affects ocean–atmosphere interaction at MJO scales. Until mid-February, local surface fluxes consistent with a convectively suppressed MJO phase drove near-surface ocean evolution. With the advection of a fresh-core eddy to the glider location in late February, ocean dynamics then becomes an additional driver of this evolution by modulating local stratification and generating a barrier layer of ≈12 m thickness for 10 days. One-dimensional modelling experiments based on the ocean and atmospheric conditions experienced during our sampling period show that the ocean subsurface structure within the eddy induce changes in SST of physical significance for ocean-atmosphere interaction. Moreover, results also suggest that the presence of a thick eddy-induced barrier layer during the MJO suppressed phase modulates the magnitude of temperature anomalies forced by surface fluxes during the following enhanced MJO phase. As eddies are abundant in this area, their dynamics must be considered to correctly represent SST variability for MJO modelling.</p></div>","PeriodicalId":11120,"journal":{"name":"Deep-sea Research Part Ii-topical Studies in Oceanography","volume":"216 ","pages":"Article 105396"},"PeriodicalIF":2.3,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141439160","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":"Prokaryotic diversity in the sponges Mycale (Oxymycale) acerata (Kirkpatrick, 1907) and Dendrilla antarctica (Topsent, 1905) from two distant Antarctic marine areas: South Cove at Rothera Point (Adelaide Island, Western Antarctic Peninsula) and Thetys Bay (Terra Nova Bay, Ross Sea)","authors":"Angelina Lo Giudice ,&nbsp;Maria Papale ,&nbsp;Maurizio Azzaro ,&nbsp;Carmen Rizzo","doi":"10.1016/j.dsr2.2024.105391","DOIUrl":"https://doi.org/10.1016/j.dsr2.2024.105391","url":null,"abstract":"<div><p>The Antarctic environment offers a unique opportunity to study the interactions between Porifera and their microbial symbionts. Reports on the association between prokaryotes and Antarctic sponges are increasing. However, a comparison of the bacterial communities associated to the same sponge species but inhabiting different Antarctic areas has seldom been addressed. This study explored the prokaryotes associated with the sponge species <em>Mycale</em> (<em>Oxymycale</em>) <em>acerata</em> (Kirkpatrick, 1907) and <em>Dendrilla antarctica</em> (Topsent, 1905) collected from South Cove at Rothera Point (Antarctic Peninsula) and Thetys Bay (Ross Sea). In <em>D. antarctica</em>, some groups were equally represented at both sites (e.g., <em>Amylibacter</em>, <em>Cutibacterium</em>, <em>Yoonia-Loktanella</em>), whereas members in the genera <em>Polaribacter</em> and <em>Kistimonas</em> were more abundant in Rothera. Similarly, <em>M. acerata</em> individuals collected from Rothera showed a higher relative abundance of some bacterial genera, such as <em>Polaribacter</em>, <em>Sulfitobacter</em>, and <em>Ulvibacter</em>. The results allowed us to identify some taxa common to sponges belonging to the same species and highlighted the possible influence of site-specific environmental conditions in shaping symbionts.</p></div>","PeriodicalId":11120,"journal":{"name":"Deep-sea Research Part Ii-topical Studies in Oceanography","volume":"216 ","pages":"Article 105391"},"PeriodicalIF":3.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141291159","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":"Finding boundaries in the sea: The Main and Small Gap of the Emperor Seamount Chain as a biogeographic boundary for bathyal benthic fauna","authors":"Les Watling ,&nbsp;John R. Smith ,&nbsp;Scott C. France ,&nbsp;Amy Baco ,&nbsp;Henrietta Dulai ,&nbsp;Glenn S. Carter ,&nbsp;E. Brendan Roark","doi":"10.1016/j.dsr2.2024.105394","DOIUrl":"https://doi.org/10.1016/j.dsr2.2024.105394","url":null,"abstract":"<div><p>Studies on the bathyal fauna of northern Pacific waters suggested that a transition or boundary between the North Pacific Province and Central Pacific Provinces would be found somewhere along the Emperor Seamount Chain. Strong currents flow west to east across the seamount chain in a region known as the Main Gap and it was proposed that any larvae produced either north or south of the Main Gap would not be capable of crossing the gap. An expedition to test the hypothesis that a faunal change would be found in the vicinity of the Main Gap was conducted in 2019. Eleven ROV dives were conducted, one on an unnamed seamount at the southern edge of Hess Rise, and 10 dives on seven seamounts along the Emperor Seamount Chain. Six dives were on seamounts north of the Main Gap, while four (including the dive on Hess Rise) were on the southern side. Of the six northern dives, three were at deeper depths (∼2000–1800 m) and three were shallower (∼1500–1100 m); of the southern dives two were at the deeper depths and two were shallower. One shallower dive occurred on Jingu Seamount, situated on the southern edge of the Main Gap. Analysis of the fauna from both collected specimens and annotations of the dive video produced four clusters: <strong>a</strong>, the four dives south of the Main Gap; <strong>b</strong>, the three deeper dives north of the Main Gap; <strong>c</strong>, the shallower dive at Jingu Seamount; and <strong>d</strong>, the four shallower bathyal dives north of the Main Gap. It was concluded that the bathyal fauna underwent a significant change from north to south across the area of the Main Gap and the adjacent Small Gap, in the area of 37–39 °N, covering distances as small as 75 km or as much as 400 km.</p></div>","PeriodicalId":11120,"journal":{"name":"Deep-sea Research Part Ii-topical Studies in Oceanography","volume":"216 ","pages":"Article 105394"},"PeriodicalIF":3.0,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141249523","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":"Microzooplankton and phytoplankton of Ross Sea polynya areas and potential linkage among functional traits","authors":"Marina Monti-Birkenmeier ,&nbsp;Tommaso Diociaiuti ,&nbsp;Francesco Bolinesi ,&nbsp;Maria Saggiomo ,&nbsp;Olga Mangoni","doi":"10.1016/j.dsr2.2024.105393","DOIUrl":"https://doi.org/10.1016/j.dsr2.2024.105393","url":null,"abstract":"<div><p>The Ross Sea is characterized by a series of subsystems with different characteristics making it an extremely productive area. To understand whether species composition and functional traits of the plankton community can be used as biological tracers, we have analyzed the composition of phytoplankton and microzooplankton, and their potential relationships, in two different polynyas of the Ross Sea during the austral summer 2017. Sampling activities were carried out near Terra Nova Bay, between Cape Washington and the northern shore of the Drygalski Ice Tongue, and in the South-Central Ross Sea. We investigated the phytoplankton and microzooplankton structure using the phytoplankton body size classes and the tintinnids lorica oral diameter as functional traits, speculating on the relationship between the two plankton communities and their use as biological indicators in a changing Southern Ocean. Our data showed significant differences in terms of plankton composition and related functional traits between the two areas, suggesting the existence of distinct ecological dynamics despite the similar total carbon content. In Terra Nova Bay, heterotrophic dinoflagellates were the most abundant microzooplankton, in association with a large phytoplankton biomass mainly represented by diatoms and nano- and micro-phytoplankton. Tintinnids with large lorica oral diameters were abundant in Central Ross Sea, where phytoplankton was dominated by <em>Phaeocystis antarctica</em> and by the micro size class. Among microzooplankton<em>, Protoperidinium defectum, P</em>. <em>applanatum</em> and <em>P</em>. <em>incertum</em> were the most abundant dinoflagellates species, while <em>Codonellopsis gaussi, C</em>. <em>gaussi</em> forma <em>cylindroconica, Laackmanniella prolongata</em> and <em>Cymatocylis drygalskii</em> were the most abundant tintinnids. The phytoplankton was dominated by diatoms <em>Pseudo-nitzschia subcurvata</em>, <em>Fragilariopsis cylindrus</em>, <em>F</em>. <em>curta</em> and by the haptophyte <em>P</em>. <em>antarctica</em>. Our data indicate that beyond physical and chemical features defining distinct sectors of the Ross Sea, both species composition and functional traits of phytoplankton and microzooplankton represent a valid monitoring tool, especially with the ongoing global warming and its effects on Antarctic food webs.</p></div>","PeriodicalId":11120,"journal":{"name":"Deep-sea Research Part Ii-topical Studies in Oceanography","volume":"216 ","pages":"Article 105393"},"PeriodicalIF":3.0,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0967064524000377/pdfft?md5=e42fe90eb95206d8c7ed04d7b2b55406&pid=1-s2.0-S0967064524000377-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141303543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diel variations in the upper layer biophysical processes using a BGC-Argo in the Bay of Bengal","authors":"Sudeep Das,&nbsp;Sourav Sil","doi":"10.1016/j.dsr2.2024.105392","DOIUrl":"https://doi.org/10.1016/j.dsr2.2024.105392","url":null,"abstract":"<div><p>The marine environment is a crucial component of global biogeochemical cycles. Recent BGC-Argo observations provide new opportunities to study the profiles of biogeochemical parameters. The study analyzed the diurnal variations of temperature, salinity, chlorophyll-a and dissolved oxygen using a high-frequency (∼5 h) cycle BGC-Argo float in the Bay of Bengal. The hydrography showed the existence of a strong barrier layer with a thickness of around 30 m, with fresh water on top and an inversion layer within it. Analysis showed that the Mixed Layer Depth (MLD) was dominated by diffuse convection, while the Isothermal Layer Depth (ILD) exhibited salt-fingering regimes. In the upper layer (0–60 m), temperature showed significant variation on a daily scale; however, notable changes were not observed for salinity. Additionally, temperature and chlorophyll-a were found to be strongly linked to solar insolation. The mean chlorophyll-a in the upper layer increased from 0600 h and peaked around 1800 h local time. However, surface chlorophyll-a increased only from 1100 h to 1800 h. It is suggested that this difference between surface and mean chlorophyll-a during high availability of sunlight was due to the process of photoacclimation. The dissolved oxygen cycle closely followed the variability of biomass production. The similarity between dissolved oxygen and the difference between the surface and mean chlorophyll-a further indicated photoacclimation variations on a diurnal scale. The Sverdrup model was used to indicate luminosity and an accumulation time of 14 h was used to show a strong correlation with diel chlorophyll-a variation. The work highlights the importance of having high-frequency BGC-Argo floats with finer vertical resolution and the need for time-series observations of biological parameters in the Bay of Bengal.</p></div>","PeriodicalId":11120,"journal":{"name":"Deep-sea Research Part Ii-topical Studies in Oceanography","volume":"216 ","pages":"Article 105392"},"PeriodicalIF":3.0,"publicationDate":"2024-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141163308","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 description of two new deep-sea nemerteans from North Pacific with reconsideration of the genus Oerstedia (Hoplonemertea, Oerstediidae)","authors":"Alexei V. Chernyshev,&nbsp;Vasiliy G. Kuznetsov","doi":"10.1016/j.dsr2.2024.105390","DOIUrl":"https://doi.org/10.1016/j.dsr2.2024.105390","url":null,"abstract":"<div><p>To date, a total of 30 nemertean species have been described from depths greater than 1000 m. All deep-sea species of the infraorder Oerstediina belong to the genera found at great depths only. A new species of the genus <em>Oerstedia</em> Quatrefages, 1846 (<em>O. sashae</em> sp. nov.), whose described species inhabit shallow waters, has been collected on the Emperor Seamounts from a depth of 1407 m. <em>Oerstedia sashae</em> sp. nov. differs from the other species of the genus by the lack of eyes. Another new species, <em>Oerstedia sofiae</em> sp. nov., which is very close to the symbiotic <em>Cryptonemertes actinophila</em> (Bürger, 1904), has been described from the Sea of Okhotsk, from a depth of 250–490 m. A phylogenetic analysis based on five gene markers (COI, 16 S, 18 S, 28 S, and histone H3) has shown that <em>O. sashae</em> sp. nov., <em>O. sofiae</em> sp. nov., and <em>C. actinophila</em> belong to clade <em>Paroerstediella</em> of the genus <em>Oerstedia</em>. <em>Cryptonemertes actinophila</em> is here proposed to be transferred to the genus <em>Oerstedia</em>. <em>Oerstedia sofiae</em> sp. nov. and <em>O. actinophila</em> comb. nov. differ from the other species of the genus by the red blood and a very short proboscis and rhynchocoel.</p></div>","PeriodicalId":11120,"journal":{"name":"Deep-sea Research Part Ii-topical Studies in Oceanography","volume":"216 ","pages":"Article 105390"},"PeriodicalIF":3.0,"publicationDate":"2024-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141242085","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":"Study of upwelling and mixing process in the Somali coastal region using satellite and numerical model observations: A Lagrangian approach","authors":"Jai Kumar,&nbsp;Smitha Ratheesh,&nbsp;Neeraj Agarwal,&nbsp;Rashmi Sharma","doi":"10.1016/j.dsr2.2024.105381","DOIUrl":"https://doi.org/10.1016/j.dsr2.2024.105381","url":null,"abstract":"<div><p>During the summer monsoon, the Somali region undergoes a significant upwelling phenomenon that enhances plankton productivity, thereby benefiting fisheries. Wind and coastal dynamics initially drive this upwelling, but eventually, eddy flows influence it. Our study explores the interplay between ocean currents, eddies, and chlorophyll-a concentrations using the backward Finite-Size Lyapunov Exponents (bFSLEs) technique. We also delve into the specific role of Ekman transport in distributing chlorophyll-a across the region. The Great Whirl (GW), an anticyclonic eddy, predominantly causes strong downwelling, interrupting the summer monsoon upwelling along the Somali coast longitudinally. Despite the GW's significant impact on moving upwelled water offshore, the influence of downwelling diminishes northward. As a result, the northern Somali coast, especially around 9°N and 10°N, showcases the most extensive offshore upwelling, reaching as far as 55°E. Our findings highlight a robust connection between chlorophyll-a levels and oceanic dynamics, influenced by both currents and eddies, as evidenced by bFSLEs, and by cross-shore Ekman transport, particularly within chlorophyll-a concentrations ranging from 0.2 to 0.6 mg m⁻³. The data suggests that Ekman transport-induced upwelling primarily drives coastal phytoplankton biomass. Furthermore, bFSLEs analysis underlines the supportive role of ocean currents and eddies in the offshore distribution of chlorophyll-a, especially near the coast. Further examination of lagged correlations reveals a temporal lag between peak concentrations of chlorophyll-a and Ekman transport; the lag increases offshore and is at least 9 days near the coast.</p></div>","PeriodicalId":11120,"journal":{"name":"Deep-sea Research Part Ii-topical Studies in Oceanography","volume":"216 ","pages":"Article 105381"},"PeriodicalIF":3.0,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141068666","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":"Mesoscale eddies in the Gulf of Mexico: A three-dimensional characterization based on global HYCOM","authors":"Yingjun Zhang ,&nbsp;Chuanmin Hu ,&nbsp;Dennis J. McGillicuddy Jr. ,&nbsp;Yonggang Liu ,&nbsp;Brian B. Barnes ,&nbsp;Vassiliki H. Kourafalou","doi":"10.1016/j.dsr2.2024.105380","DOIUrl":"https://doi.org/10.1016/j.dsr2.2024.105380","url":null,"abstract":"<div><p>The Gulf of Mexico (GoM) is characterized by strong mesoscale eddy activities that have been studied extensively, yet the comprehensive three-dimensional (3-D) kinematic properties of GoM eddies are still not well documented. In this study, the 3-D mesoscale eddy activities in the upper layer (0–800 m) of the GoM are characterized using 14-year (1997–2010) global Hybrid Coordinate Ocean Model (HYCOM) outputs. Most eddies in the upper layer (both cyclonic and anticyclonic) have radii of ∼30–60 km and lifespans shorter than 30 days. The spatial distributions of GoM eddies do not vary much with depth, while their intensity decreases with depth. The size of cyclonic eddies does not vary much with depth, while the size of anticyclonic eddies decreases slightly with depth. Cyclonic eddies are often found to be generated in the eastern GoM (especially in the Loop Current region), the Bay of Campeche, and on the continental slope of the Campeche Bank, while anticyclonic eddies are often generated on the northeastern and northwestern GoM continental slopes, and in the central GoM (near 24°N) and the Bay of Campeche (92–94°W). In addition, long-lived GoM eddies (e.g., lifespan &gt;150 days) tend to have intermediate eddy intensity (e.g., 0.13–0.32 for cyclonic eddies at the 10 m level). Both cyclonic and anticyclonic eddies are found to play an important role in the horizontal and vertical transport of heat and salt, and eddy-induced anomalies of water temperature and salinity at both surface and subsurface are generally more pronounced in the eastern GoM than in the western GoM.</p></div>","PeriodicalId":11120,"journal":{"name":"Deep-sea Research Part Ii-topical Studies in Oceanography","volume":"215 ","pages":"Article 105380"},"PeriodicalIF":3.0,"publicationDate":"2024-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141066707","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 influence of aeolian input on the trace and rare earth element composition of Oligocene-Miocene corals of KOKO Guyot (Emperor seamount chain, Pacific Ocean)","authors":"Irina A. Vishnevskaya ,&nbsp;Tatiana G. Okuneva ,&nbsp;Daria V. Kiseleva ,&nbsp;Natalia G. Soloshenko ,&nbsp;Pavel E. Mikhailik","doi":"10.1016/j.dsr2.2024.105377","DOIUrl":"https://doi.org/10.1016/j.dsr2.2024.105377","url":null,"abstract":"<div><p>The Hawaiian–Emperor Seamount Chain is composed of seamounts capped with fossil coral reef deposits that originally formed close to sea level but are now covered by hundreds of meters of water owing to prolonged subsidence. These fossil reef deposits are important archives of paleoenvironmental change and retain possible traces of Aeolian input from continental Asian dust. We studied the trace and rare earth element composition of Oligocene-Miocene coral reef limestone of Koko guyot aged 25–6 Ma to assess the influence and possible increase of continental allothigenic material input that could persist in marine carbonates. The composition of trace and rare earth elements of modern coral and ancient limestones demonstrated that they had inherited the composition of sea water. Positive europium anomaly observed in modern coral and calcified echinoid spines aged 0–50 thousand years was absent in ancient limestones. This effect could be associated with a change in the oxidation state during diagenesis and recrystallization, which probably led to the loss of europium. The distribution of trace and rare earth elements was constant in carbonate rocks of different ages despite the increase of aeolian input, which confirmed the earlier conclusions about the restriction of incorporation of certain elements into the crystal lattice of carbonate minerals, and demonstrated the regulating role of seawater. In addition, trace and rare earth elements, even if they were adsorbed on the thin films of biological objects during their life, obviously didn't persist there after burial.</p></div>","PeriodicalId":11120,"journal":{"name":"Deep-sea Research Part Ii-topical Studies in Oceanography","volume":"215 ","pages":"Article 105377"},"PeriodicalIF":3.0,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140621856","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}