Depositional Record最新文献

{"title":"Carbonate sedimentology: An evolved discipline","authors":"Noel P. James,&nbsp;Peir K. Pufahl","doi":"10.1002/dep2.70042","DOIUrl":"https://doi.org/10.1002/dep2.70042","url":null,"abstract":"<p>Although admired and examined since antiquity, carbonate sediment and rock research really began with Charles Darwin who, during a <i>discovery phase</i>, studied, documented and interpreted their nature in the mid-19th century. The modern discipline, however, really began after World War II and evolved in two distinct phases. Breakthroughs during an <i>advancement phase</i> came about via the numerous studies by many researchers globally on both modern and ancient carbonates that were eventually merged into carbonate sedimentology as a whole in the 1970s. Formulation of the factory concept and integration of recurring facies into facies models solidified the discipline and allowed integration to move ahead. Stromatolites were discovered growing in modern environments and it was realised that the spectrum of diverse fossil structures called reefs also existed in the modern world. Internal reef structure was largely interpreted as ecological. At the same time, development of radiogenic and stable isotopes allowed Pleistocene carbonate stratigraphy and processes to be accurately dated, and precipitates related specific formation waters. Cementation, long postulated as mostly meteoric, was also realised to be a common synsedimentary phenomenon. Breakthroughs during the more recent <i>refinement phase</i> were likewise synthesised into books, but incrementally as the science progressed. Research on the genesis of critical components such as ooids, stromatolites and carbonate muds was at last convincing. The whole new realm of cool-water carbonates was revealed with resulting different interpretations of rock record facies and the critical role of aragonite in diagenesis. Reconciling the relationship between sea water nutrient levels, factory type and taphonomy was a major advancement to interpreting the stratigraphic record. Sequence stratigraphy, coupled with shallow drilling and isotopes, led to progressively more dynamic interpretations, especially of reefs. Use of stable isotopes became more sophisticated, and development of clumped isotopes held out possibilities of even more precise interpretations. Finally, although prediction of a <i>future phase</i> is futile, much more needs to be done on mixed carbonate-siliciclastic systems, and the implications of mixed carbonate ironstone and chert in Precambrian accumulations, especially using new geochemical techniques. Perhaps, philosophically, it is time to use attributes of the exquisite carbonate rock record to tell us about the future of our rapidly changing world.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"12 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.70042","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145964442","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":"Orbital and eustatic control of basin hydrology during the first stage of the Messinian Salinity Crisis","authors":"Fernando Gázquez,&nbsp;Nicholas P. Evans,&nbsp;Thomas K. Bauska,&nbsp;Harold J. Bradbury,&nbsp;Alexandra V. Turchyn,&nbsp;María del Carmen Barroso,&nbsp;Alexander M. Piotrowski,&nbsp;José María Calaforra,&nbsp;David A. Hodell","doi":"10.1002/dep2.70045","DOIUrl":"https://doi.org/10.1002/dep2.70045","url":null,"abstract":"<p>Gypsum and marls from the 15 cycles of the Messinian Yesares Member in the Sorbas Basin, SE Spain, were analysed using a multi-isotope approach to reconstruct palaeo-hydrological conditions of the basin and the wider Mediterranean region during the deposition of the Primary Lower Gypsum (PLG) of the Messinian Salinity Crisis (MSC) (~5.97–5.60 Ma). By analysing structurally-bound water in sedimentary gypsum (CaSO₄·2H₂O), the past oxygen and hydrogen isotopic composition of waters during evaporite formation is determined. These measurements are combined with water salinity inferred from gypsum fluid inclusions and isotopic analysis of strontium (⁸⁷Sr/⁸⁶Sr), calcium (δ⁴⁴/⁴⁰Ca), sulphur (δ³⁴S) and oxygen of sulphate (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msup>\u0000 <mi>δ</mi>\u0000 <mn>18</mn>\u0000 </msup>\u0000 <msub>\u0000 <mi>O</mi>\u0000 <msub>\u0000 <mi>SO</mi>\u0000 <mn>4</mn>\u0000 </msub>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ {updelta}^{18}{mathrm{O}}_{{mathrm{SO}}_4} $$</annotation>\u0000 </semantics></math>) in the same samples, as well as isotopic analysis (δ⁴⁴/⁴⁰Ca, ⁸⁷Sr/⁸⁶Sr, δ¹⁸O_carb, δ¹³C) of the interbedded carbonate marls. The PLG in the Sorbas Basin did not form solely from the evaporation of seawater but rather precipitated from a hybrid brine consisting of seawater and a significant input of freshwater. The seawater/freshwater ratio changed through time and was influenced by (1) tectonic uplift and basin restriction, (2) obliquity-driven glacial–interglacial sea level changes and (3) precession-driven freshwater influx. A progressive freshwater increase up-section reflects tectonic restriction of the basin, supported by ⁸⁷Sr/⁸⁶Sr trends, which start at seawater values in Cycle 2 and deviate upward. Two minor reversals in ⁸⁷Sr/⁸⁶Sr at ~5.84 and ~5.72 Ma reflect the role of obliquity-controlled sea level and eccentricity-modulated precession. Maximum divergence of ⁸⁷Sr/⁸⁶Sr from the seawater curve, as well as precipitation of authigenic dolomite with high δ¹⁸O_carb, represent a temporary regime change to a freshwater-dominated system coincident with the strongest glacial stages (Marine Isotope Stage TG20) and an eccentricity minimum at ~5.75 Ma. A gradual tectonic restriction of the Atlantic connection, superimposed on orbitally controlled glacio-eustatic (obliquity-dominated) and freshwater input (precession-dominated) changes, led to gypsum-marl deposition in Mediterranean marginal basins during the early MSC.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"12 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.70045","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145970152","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":"Correction to ‘Trace elements, rare earth elements and isotopes of poorly preserved fossils from lower Cretaceous carbonates (Eastern Black Sea): Implications for early diagenetic alteration’","authors":"","doi":"10.1002/dep2.70050","DOIUrl":"https://doi.org/10.1002/dep2.70050","url":null,"abstract":"<p>Özyurt, M. (2025) Trace elements, rare earth elements and isotopes of poorly preserved fossils from lower Cretaceous carbonates (Eastern Black Sea): Implications for early diagenetic alteration. <i>The Depositional Record</i>, 11, 1107–1131. Available from: 10.1002/dep2.70026</p><p>In the Methodology section, the electron microprobe analyses were performed at LMU Munich, not at the University of Hamburg. The electron beam current was 2 nA, not 20 nA, and the electron beam size was 5 μm, not 10 μm.</p><p>In the Acknowledgements section, the correct institutional affiliation for Dr. Dirk Müller, who provided help with the electron microprobe analyses, is LMU Munich, not the University of Hamburg.</p><p>The author apologises for these errors.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"12 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.70050","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145958161","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":"Differentiating hyperpycnal, hypopycnal and turbidity current deposits in late Quaternary glaciogenic mud","authors":"Omar N. Al-Mufti,&nbsp;R. William C. Arnott,&nbsp;Marc J. Hinton,&nbsp;Hazen A. J. Russell","doi":"10.1002/dep2.70048","DOIUrl":"https://doi.org/10.1002/dep2.70048","url":null,"abstract":"<p>The fate of sediment-laden density flows is strongly controlled by the density contrast between the flow and the basin fluid, which fundamentally influences the character of the sedimentary deposit. However, differentiating the deposits of hyperpycnal and hypopycnal flows, in addition to slope-failure-related turbidity currents, remains a source of debate. In part, this can be attributed to the difficulty in determining the density of the fluid in an ancient depositional basin. In this study of a nearly modern succession of fine-grained (silt-clay) glaciogenic deposits, basin fluid conditions are well-constrained and the sedimentological make-up of these sediments was determined using X-ray computed tomography and microscopy. Deposits of bottom-hugging hyperpycnal flows consist of a distinctive alternating pattern of silt-rich and clay-rich laminae attributed to the rhythmic alternation of shear thinning and shear thickening processes in the mm- to sub-mm-thick, non-Newtonian very-near-bed region. A similar pattern is observed in fine-grained turbidites, suggesting similarity in depositional mechanism. This similarity suggests that differentiating the deposits of fine-grained hyperpycnal flows from turbidity currents based solely on physical stratal attributes is challenging. Alternatively, hypopycnal flows form buoyant plumes from which sediment settles, spawning bottom-hugging secondary turbidity currents. In these flows, insufficient sediment concentration and shear stress prevent shear thinning and shear thickening processes from operating, and instead, entropic Brownian fluid motion results in an unstratified deposit with a disorganised fabric. Additionally, these strata contain irregularly spaced, well-sorted silt lenses that range from a single silt grain to a few silt grains thick and record outer flow disturbances that reworked the previously deposited silt and clay. Whereas differentiating fine-grained hypopycnal flow deposits from hyperpycnal flows or turbidity currents may be straightforward, differentiating them from pure suspension fallout would appear to rely on the recognition of the thin, well-sorted silt lenses indicating advection rather than pure particle settling.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"12 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.70048","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145987140","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":"Sediment-stressed reefs over the past 420 Myr","authors":"Tanja Unger,&nbsp;Stephen W. Lokier,&nbsp;Markus Aretz,&nbsp;Matthieu Saillol,&nbsp;Adrian Immenhauser","doi":"10.1002/dep2.70040","DOIUrl":"https://doi.org/10.1002/dep2.70040","url":null,"abstract":"<p>Worldwide, reefs are under significant pressure, and hence, understanding the consequences of natural and anthropogenically driven sediment influx to reef systems is crucial to planning future protection strategies. Most reef systems are associated with clear water settings, but reefs also evolved in turbid water environments stressed by high rates of sediment influx. Mixed carbonate–clastic environments have been considered unfavourable to reef-building organisms. Currently, we lack generally applicable models for (i) reef growth under the stress of siliciclastic sediment influx and (ii) tools that diagnose ancient reefs that developed in sediment-stressed environments. Case studies of sediment-stressed reefs from the Devonian to the recent reviewed here demonstrate that reef organisms show the ability to survive, and even thrive, under clastic sediment influx. These case studies were selected based on (i) the presence of a mixed carbonate-clastic matrix and (ii) the existence of a coral framework. For each example, the system was characterised in terms of sediment input, organism growth forms and the overall reef architecture. The host sediment from Cenozoic reefs is typically better described than that within Palaeozoic and Mesozoic communities. This may be due to the closer affinity between Cenozoic communities and recent species compared to more ancient systems. The same reasoning accounts for the paucity of data describing the internal structure of many fossil reefs, a feature also related to outcrop quality. Moreover, the juxtaposition of siliciclastic interbeds and ancient reefal bodies should not be taken as conclusive evidence that clastic influx was contemporaneous with the active growth stages of the framework organisms. Based on the data reviewed here, no relationship was identified between the nature of the reef builders, the character of the siliciclastic component and the reef structure. We suggest that this lack of understanding of mixed carbonate-clastic reef systems significantly compromises potential forecasts of future reef development.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"12 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.70040","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145983461","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":"Deciphering depositional controls and evolution of a lacustrine supradetachment basin through facies analysis: Gördes Basin, Western Türkiye","authors":"Ayhan Ilgar,&nbsp;Alper Bozkurt,&nbsp;Tolga Esirtgen,&nbsp;Ali Ergen,&nbsp;Ercan Tuncay,&nbsp;Sema Çobankaya","doi":"10.1002/dep2.70047","DOIUrl":"https://doi.org/10.1002/dep2.70047","url":null,"abstract":"<p>The lacustrine Gördes Supradetachment Basin developed along the Simav Detachment Fault during the Early–Middle Miocene postorogenic extension in the north of the Menderes Massif in western Anatolia. The basin-fill consists of alluvial fan, Gilbert-type delta, shoal-water delta, foreshore, shoreface, offshore-transition and peat-forming mire deposits. The alluvial fans and fan deltas deposited along all the margins serve as sensitive recorders of tectonic, climatic, and base-level variations. Process-based facies analyses of the alluvial fan and fan-delta deposits provide an excellent opportunity to reconstruct the palaeogeographical evolution. The alluvial fans consist of braided channel-fill, hyperconcentrated flow and debris flow facies, indicating high-energy sediment transport mechanisms. Progradational wedges of Gilbert-type fan deltas formed atop the alluvial fans reflect a rapid rise in lake level. This rise resulted from asymmetrical subsidence of the basin floor, which shifted the water mass laterally, causing rapid regression on one coast and coeval transgression on the other. Changes in basin floor configuration in the Gördes Basin were driven by movement of the Simav Detachment Fault on the southern margin, while the hanging wall was segmented by an antithetic normal fault on the northwestern margin. Consequently, faulting on both sides increased the depth of the accommodation through a sudden lake level rise. Climate controlled both the lake water budget and the catchment sediment yield. The subsidence rate subsequently decelerated, sediment yield decreased and shallow lake conditions prevailed on the NW margin, as evidenced by the shoal-water deltas. This occurred due to tectonic activity insufficient to produce the large-scale deepening required for Gilbert-type delta development. Finally, the clastic components of the offshore transition facies diminished as the carbonate content increased towards the basin's interior and in the upper parts of the succession during the maximum lake expansion.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"12 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.70047","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145970190","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":"Cooling climate across last interglacial high stands on San Salvador and Great Inagua, The Bahamas","authors":"Ian Winkelstern,&nbsp;Sierra Petersen,&nbsp;H. Allen Curran,&nbsp;Cecilie Phillips,&nbsp;Alex Quizon,&nbsp;Bosiljka Glumac,&nbsp;David Griffing","doi":"10.1002/dep2.70038","DOIUrl":"https://doi.org/10.1002/dep2.70038","url":null,"abstract":"<p>The last interglacial (LIG) is the last time global climate was about as warm as today, with global sea-levels several metres higher. The LIG probably had a reduced latitudinal temperature gradient, with warmer poles and cooler tropics than today. Well-constrained records from low latitudes can test this overall model. We used bivalve shells sampled from six localities thought to expose the LIG age Cockburn Town Member of the Grotto Beach Formation on both San Salvador and Great Inagua Islands, The Bahamas. Previous work described two LIG depositional intervals: older ‘Reef I’ and younger ‘Reef II’, separated by a disconformity. New amino acid racemisation (AAR) data were used to date each locality in this context and clumped isotope palaeothermometry was used to reconstruct LIG temperatures and the isotopic composition of sea water. AAR data are described from six sites: four with similar AAR values to the well-dated Reef II Cockburn Town site, one Reef I age site on Great Inagua and one distinctly younger outcrop on San Salvador previously thought to be LIG age that may be MIS 5a. All LIG shells record cooler than modern conditions. The Δ₄₇ thermometry shows that the Reef I-age shell population preserves the warmest mean temperature (25 ± 2°C) and most positive water δ¹⁸O values (+0.7 ± 0.4‰) across all sites. This contrasts with cool mean temperatures (~21–23°C) and fresher water δ¹⁸O values (−0.5 to +0.6‰) found from Reef II populations. Regional glacial isostatic adjustment through the LIG would have resulted in peak sea levels that post-dated peak LIG temperatures. It is suggested that apparent cooler temperatures of Reef II do not reflect peak LIG temperatures but instead document the beginning of cooling into MIS 5d. Comparison with Δ₄₇ data from Bermuda supports a reduced latitudinal gradient throughout the LIG.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"12 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.70038","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145964436","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":"Mechanisms of near-normal sea water dolomitisation: Mesohaline-reflux or syn-depositional?","authors":"Misbahu Abdullahi,&nbsp;Adhipa Herlambang,&nbsp;Khalid Al-Ramadan,&nbsp;Ardiansyah Koeshidayatullah","doi":"10.1002/dep2.70039","DOIUrl":"https://doi.org/10.1002/dep2.70039","url":null,"abstract":"<p>The Eocene Epoch is characterised by multiple hyperthermals, which promoted extensive carbonate sediment deposition and dolomitisation, particularly across the Arabian Plate. The Dammam Formation, a key Eocene aquifer and hydrocarbon-bearing unit in the Arabian platform, is extensively dolomitised. Several models have been proposed to explain its dolomitisation, many of which invoke sea water or its derivatives as the dolomitising fluid. However, the specific sea water-driven mechanisms remain poorly understood. More broadly, the effectiveness of commonly used diagenetic proxies (e.g. stable isotopes, stoichiometry and trace elements) in distinguishing between closely related sea water-driven dolomitisation processes has not been systematically assessed. This study addresses these issues by integrating petrographic, mineralogical, chemical and stable isotopic (δ¹³C and δ¹⁸O) analyses of a shallow subsurface core from the Dammam Formation. Two distinct dolomite types were identified: Type I (TI), predominantly subhedral and Type II (TII), exhibiting euhedral and subhedral textures. Both types are pervasive, fabric non-selective and non-mimetic. The dolomite pre-dates all other diagenetic processes, such as the formation of palygorskite, calcite, pyrite and stylolite, indicating early, shallow emplacement. Mineralogical data reveal that TI dolomite is near-stoichiometric (51.4 mol%CaCO₃), and well-ordered, while TII is non-stoichiometric (56.3 mol%CaCO₃) and poorly ordered. Trace element concentrations (Fe, Mn, Sr) align with some previously reported sea water dolomites. The δ¹⁸O values (−2.59‰ to 0.95‰) and temperatures (24–40°C) suggest formation within Eocene marine conditions, with potential evidence of warmer fluids or recrystallisation. The δ¹³C values (0.89–1.83‰) indicate buffering during dolomitisation, consistent with Eocene sea water. Contrary to previous interpretations suggesting sabkha mixing or evaporated sea water, this study proposes that the Saudi Dammam dolomite formed primarily through normal-to-mesohaline sea water dolomitisation, driven most probably by reflux of mesohaline fluids. This study adds to the understanding of sea water-driven dolomitisation, emphasising that recrystallisation can make distinction between mesohaline reflux and syn-depositional sea water-driven mechanism, in shallow marine dolomitised carbonates, challenging.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"12 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.70039","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145964454","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":"Whitings in the Red Sea","authors":"Manuel Ariza-Fuentes,&nbsp;Akbar Wicaksono,&nbsp;Elisa Garuglieri,&nbsp;Vincent Saderne,&nbsp;Indah Putri,&nbsp;Francesca Giovenzana,&nbsp;Regina Iakusheva,&nbsp;Ibrahim Hoteit,&nbsp;Volker Vahrenkamp","doi":"10.1002/dep2.70041","DOIUrl":"https://doi.org/10.1002/dep2.70041","url":null,"abstract":"<p>Marine whitings are enigmatic phenomena characterised by milky water plumes rich in suspended aragonite needles, believed to contribute significantly to mud deposition in ancient carbonate systems. Their formation remains debated, with mechanisms including chemical precipitation due to oversaturation, sediment resuspension or carbonate sand abrasion. This study presents the first report of whitings in the Red Sea, specifically in the southern outer lagoon of Al Wajh Lagoon. Using PlanetScope satellite imagery, in situ loggers (temperature, pH, currents), sea water chemistry, CTD profiles, sediment and SEM analyses, we identified 21 whiting events between June 2021 and November 2022. The largest whiting, in December 2021, covered 51 km². All whitings were preceded by westerly winds (&gt;5.4 m s⁻¹), sudden deep-lagoon temperature anomalies (up to 1.7°C) and strong inflow currents (up to 0.6 m s⁻¹). During a September 2022 event, pH remained constant (~8.35) for several days, disrupting typical diurnal cycles. Surface waters showed aragonite oversaturation. Sediment analyses revealed in the lagoon a 16 km² mud hotspot, enriched in aragonite needles (&gt;80% in weight content). The prolonged duration of whitings of up to 12 days without sustained wind or wave action suggests they are not caused by sediment resuspension. Instead, anomalous pH behaviour supports a chemical precipitation origin. We propose that strong, short-lived westerly winds drive dense offshore or shallow rim sill waters into the stratified lagoon, with whitings occurring twice as often in fall/winter as in spring/summer. In fall/winter, cooling creates high-density waters in the shallows; in spring/summer, high density is created by high salinity due to strong evaporation. The cascading dense waters disrupt stratification, bringing nutrient-rich deep waters to the surface and triggering phytoplankton blooms. Resulting CO₂ drawdown raises alkalinity, which is balanced by CaCO₃ precipitation in surface waters. This study offers new insights into whiting formation and carbonate mud production in restricted tropical platforms.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"12 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.70041","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146002463","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":"Enhancing event stratigraphic correlations in the ultra-deep Japan Trench using XRF-CS cluster-based chemostratigraphy","authors":"Jyh-Jaan Steven Huang,&nbsp;Charlotte Pizer,&nbsp;Jun-Ting Lin,&nbsp;Ken Ikehara,&nbsp;Michael Strasser","doi":"10.1002/dep2.70044","DOIUrl":"https://doi.org/10.1002/dep2.70044","url":null,"abstract":"<p>Establishing along-strike correlations of event deposits in deep-sea environments allows for the reconstruction of spatial and temporal patterns of geological processes, such as seismically triggered turbidites. However, in settings like the ultra-deep Japan Trench, highly variable seafloor topography and limited chronological tie points pose significant challenges for tracing individual deposits between semi-isolated trench basins. Using cores from International Ocean Discovery Program (IODP) Expedition 386 at the central Japan Trench, this study examines how non-destructive X-ray fluorescence core scanning (XRF-CS) combined with multivariate statistics can be used to distinguish and correlate individual event deposits across contrasting depositional settings, based on their geochemical fingerprints. The results of the five-cluster model demonstrate that the XRF-CS properties of event deposits are clearly distinguishable from background sediments, as well as from one another. The chemostratigraphic cluster sequence can be correlated between cores from basin depocentres—where event deposits are thicker but the record is shorter, and cores from topographic highs—where the record extends further back in time but event deposits are thin and difficult to distinguish using previously applied event correlation methods. The high-resolution chemostratigraphy enables a more detailed, geochemically-enhanced stratigraphic interpretation, identifying several previously unrecognised event deposits with unique internal structures that suggest varying depositional processes. Notably, excluding the 2011 event deposit, the three most recent event deposits are allocated to different clusters, implying compositional heterogeneity probably linked to sediment provenance. The results of this study therefore demonstrate a rapid and reproducible technique for using chemostratigraphy to establish high-resolution event correlations in submarine sediment cores, leading to several working hypotheses for Japan Trench palaeoseismology to be tested with future work.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"12 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.70044","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145987236","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}