Sedimentary Geology最新文献

{"title":"High-resolution sequence stratigraphy of Upper Jurassic lacustrine cycles in the Parnaíba Basin, Brazil: Unraveling basin evolution through climate and thermal subsidence","authors":"Argel de Assis Nunes Sodré ,&nbsp;Afonso César Rodrigues Nogueira ,&nbsp;Juliana Charão Marques ,&nbsp;João Vicente Tavares Calandrini de Azevedo ,&nbsp;Renan Fernandes dos Santos ,&nbsp;Luiz Saturnino Andrade ,&nbsp;Leandro Freitas Sepeda ,&nbsp;Pedro Guilherme Assunção Oliveira","doi":"10.1016/j.sedgeo.2025.106933","DOIUrl":"10.1016/j.sedgeo.2025.106933","url":null,"abstract":"<div><div>Palaeolakes of the Late Jurassic, in West Gondwana, were critically shaped by thermal subsidence, driven by isostatic adjustment, isotherm downgrading, and the cooling of mafic magma associated with the Central Atlantic Magmatic Province (CAMP) around 201 Ma. These key processes are recorded in the Pastos Bons Formation, located within the Parnaíba Basin in northeastern Brazil. Although this sedimentary succession has recently been examined from a palaeoenvironmental perspective, a significant gap remains in characterizing its stacking patterns through the lens of high-resolution sequence stratigraphy (HRSS). Therefore, there remains a lack of clarity regarding the interplay between climatic and thermal subsidence and its influence on sedimentation and lake level fluctuations. Hence, we identified twenty sedimentary facies, grouped into six facies associations: central lake (FA1), hyperpycnal littoral delta (FA2), lakeshore (FA3), alluvial fan (FA4), fluvial (FA5), and delta front (FA6). The HRSS framework reveals three medium-frequency sequences, representing clusters of high-frequency T-R (transgressive-regressive) sequences, controlled by long-term climatic changes: sequence-1 (Seq-1), sequence-2 (Seq-2), and sequence-3 (Seq-3). Seq-1 and Seq-2 exhibit a higher proportion of transgressive system tract (TST) than regressive system tract (RST), and they demonstrate dramatic fluctuations in lake level. In contrast, Seq-3 shows a predominance of the regressive systems tract (RST) over the transgressive systems tract (TST), reflecting greater stability in lake level. The medium-frequency framework reveals that the Pastos Bons Formation is characterized by a balanced-fill lacustrine basin (Seq-1 and Seq-2) overlaid by an overfilled lacustrine basin (Seq-3). The low-frequency chronostratigraphic framework, composed of clusters of medium-frequency T-R sequences (seismic scale), indicates that post-CAMP thermal subsidence presents a primary control on the configuration, size, shape, and accommodation potential of the lacustrine basin. Post-CAMP subsidence along the Equatorial Atlantic margins during the Late Jurassic period played a key role in shaping the palaeogeography of West Gondwana, promoting the development of lacustrine basins.</div></div>","PeriodicalId":21575,"journal":{"name":"Sedimentary Geology","volume":"486 ","pages":"Article 106933"},"PeriodicalIF":2.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144604350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Refined Os isotope stratigraphy of ferromanganese crusts from the Arctic Ocean and implications for polar environmental change since the late Miocene","authors":"Natalia Konstantinova ,&nbsp;James R. Hein ,&nbsp;Liang Yi ,&nbsp;Yu Liu ,&nbsp;Hiroyuki Matsuzaki ,&nbsp;Qing Chang ,&nbsp;Akiko Makabe ,&nbsp;Harald Brekke ,&nbsp;Sergei Skolotnev ,&nbsp;Georgy Cherkashov ,&nbsp;Katsuhiko Suzuki","doi":"10.1016/j.sedgeo.2025.106942","DOIUrl":"10.1016/j.sedgeo.2025.106942","url":null,"abstract":"<div><div>The long-term environmental history of the Arctic region remains restricted due to the limited number of pre-Quaternary sedimentary records. We present the first Os isotope data of hydrogenetic ferromanganese crusts collected from four locations in the Arctic Ocean: Northwind Ridge, Mendeleev Ridge, Knipovich Ridge and Voring Spur; water depth varied from 1300 to 3851 m. The Os concentrations, ¹⁸⁷Os /¹⁸⁸Os ratios, and major- and trace-element compositions of sublayers (2–5 mm thick) show clear temporal variations. Be isotope ages determined for the Mendeleev Ridge crust were used to guide the ¹⁸⁷Os /¹⁸⁸Os ages of the Fe<img>Mn crusts, which were obtained by comparison of the ¹⁸⁷Os /¹⁸⁸Os ratios in the crusts with those of the Cenozoic seawater curve. The results greatly improve the Arctic Os isotope temporal record from Fe<img>Mn crust stratigraphy for the late Miocene and Quaternary.</div><div>Several groups of elements show similar behavior spatially (predominantly Ti, Ba, U, REE, Y, Nb, Hf, Cd, Zr, and Ni, Cu) and two groups temporally (Fe, V, As and Ca, Co, Pb, Th). The temporal history is characterized by variations in radiogenic Os isotope composition, which were associated with the long-term (&gt; 10⁵ yr) climatic trends in the region, such as late Miocene cooling, early-to-middle Pliocene warming, and Pliocene-Pleistocene Northern Hemisphere glaciation. The Fe<img>Mn crust growth rate decreased drastically in the late Miocene possibly due to changes in bottom water conditions associated with the final widening and deepening of the Fram Strait.</div></div>","PeriodicalId":21575,"journal":{"name":"Sedimentary Geology","volume":"486 ","pages":"Article 106942"},"PeriodicalIF":2.9,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144829085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Late Paleozoic coastal plain paleosols: Geochemical insights into soil genesis, provenance, and paleoclimate within paleoequatorial Pangea, Paradox Basin, USA","authors":"Stephanie J. White ,&nbsp;Gary E. Stinchcomb ,&nbsp;Stacy C. Atchley ,&nbsp;Stephen I. Dworkin","doi":"10.1016/j.sedgeo.2025.106934","DOIUrl":"10.1016/j.sedgeo.2025.106934","url":null,"abstract":"<div><div>Studies of ancient drylands can enhance our understanding of ecosystem responses to changing climate, but reconstructing deep-time dryland environments using paleosols is challenging because these fossil soils are often weakly developed and many proxies are not equilibrated to past climate. Paleosols from the uppermost Honaker Trail Formation and lower Cutler beds (Rico and Halgaito Formations) span the Pennsylvanian-Permian transition within the Paradox Basin of southeast Utah (USA) and are an ideal setting to explore dryland paleoenvironments. Integration of bulk oxide, micro-XRF, and stable isotopic data allows for assessments of paleoclimate, provenance, and pedogenic processes. Ti/Al ratios track a broadly consistent provenance while Ti/Zr trends follow allochthonous dust contributions, possibly indicating a shift in paleowinds near the Rico-Halgaito boundary that is supported by Ti/Zr and Zr/Hf ratios from within-zircon analysis. Carbon isotopic data suggest pedogenic carbonate formation under conditions of low soil productivity while modeled MAP estimates reveal an average of 409 mm/yr ± 209. Evaluation of MAT and MAP relationships suggests that Inceptisols identified within this study could represent ancient Aridisols. We conclude that dry climatic conditions promoted an unstable landscape for the region encompassing the study interval while also precluding hydrolysis and leaching, resulting in weakly developed paleosols with abundant carbonate features and red coloration. These findings are consistent with other work from the region, pointing to dry conditions and shifting paleowinds within paleoequatorial Pangea during the Pennsylvanian-Permian transition.</div></div>","PeriodicalId":21575,"journal":{"name":"Sedimentary Geology","volume":"486 ","pages":"Article 106934"},"PeriodicalIF":2.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144670520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sediment distribution and facies of modern tropical reefs and carbonate platforms revisited: A global perspective","authors":"Eberhard Gischler","doi":"10.1016/j.sedgeo.2025.106929","DOIUrl":"10.1016/j.sedgeo.2025.106929","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Surface sediment samples (&lt;em&gt;n&lt;/em&gt; = 886) collected on tropical reefs and carbonate platforms in the western Atlantic, the central and eastern Indian Ocean, the south and west Pacific Ocean, and the Persian Gulf have been revisited and examined in their entirety. The samples stem from twelve depositional environments, i.e., fore reef, reef margin, sand apron, shallow lagoon, deep lagoon, restricted lagoon, patch reef, island, nearshore; inner ramp, mid ramp, and outer ramp. Grain composition, texture, mineralogy, and geochemistry have been analyzed in a quantitative and statistical manner. Fragments of coral skeletons, calcareous algae (red coralline algae, &lt;em&gt;Halimeda&lt;/em&gt;), mollusk shells, and non-skeletal grains (predominantly peloids) are the most abundant constituent carbonate grains. Coralgal, grain-supported textures are common at the margins whereas mud- and grain-supported textures with mollusks, &lt;em&gt;Halimeda&lt;/em&gt;, and non-skeletal grains are ubiquitous in rimmed platform interiors. Non-rimmed platforms are characterized by non-skeletal grains on the inner ramp, while mid and outer ramps are rich in mollusk shells. Multivariate statistics of composition and texture data have been used to discern fourteen facies including (1) quartz-rich marl, (2) quartz sand, (3) foraminiferal grainstone to packstone, (4) mollusk-foraminiferal grainstone to packstone, (5) mollusk grainstone to packstone, (6) non-skeletal grainstone to packstone, (7) &lt;em&gt;Halimeda&lt;/em&gt; grainstone to packstone, (8) coral-rich grainstone, (9) quartz-rich biogenic grainstone, (10) mollusk packstone, (11) coral packstone, (12) non-skeletal packstone to wackestone, (13) wackestone, and (14) mudstone. There is a statistically significant correlation between the amount of fines (‘mud’) and water depth, i.e., depositional energy, however, individual facies exhibit large depth ranges, thereby underlining previous studies that have challenged intuitive and long-standing concepts of sediment distribution. An exception to this scheme is the ramp system in the northern Persian-Arabian Gulf where facies boundaries approximately follow bathymetric contours. Aragonite (83.2 ± 0.6 % relative abundance ± standard error of mean) and high-magnesium calcite (11.1 ± 0.6 %) are the most common carbonate phases reflecting skeletal mineralogy of producers. The abundance of low-magnesium calcite is lowest (5.2 ± 0.1 %). Stable isotopes of oxygen (δ&lt;sup&gt;18&lt;/sup&gt;O: −3 ‰ to +3 ‰) and carbon (δ&lt;sup&gt;13&lt;/sup&gt;C: −2 ‰ to +6 ‰) of bulk samples exhibit wide ranges and appear to be controlled principally by region rather than by depositional environment within reefs and carbonate platforms. Western Atlantic and south Pacific platform samples show the highest δ&lt;sup&gt;13&lt;/sup&gt;C, as a consequence of the occurrence of abundant non-skeletal grains, which are largely lacking in the open Indian Ocean samples. Samples from the Persian Gulf and Shark Bay reach the highest δ&lt;sup&gt;18&lt;/sup&gt;O due to elevated sal","PeriodicalId":21575,"journal":{"name":"Sedimentary Geology","volume":"486 ","pages":"Article 106929"},"PeriodicalIF":2.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144556625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tectono-eustasy and basin morphology controls on Cretaceous facies architecture in the northeastern margin of Arabian Plate","authors":"Borhan Bagherpour ,&nbsp;Ali Faghih ,&nbsp;Hossein Vaziri-Moghaddam ,&nbsp;Hamzeh Mehrabi ,&nbsp;Mehdi Zare ,&nbsp;Adrian Immenhauser","doi":"10.1016/j.sedgeo.2025.106943","DOIUrl":"10.1016/j.sedgeo.2025.106943","url":null,"abstract":"<div><div>Basement highs and adjacent basins are significant structural elements controlling regional facies architecture. Overprinted by fluctuating sea-levels, the correlation of facies units from the crest into the flank environments is often challenging. Here, a case example of an upper Turonian–lower Campanian palaeohigh on the northeastern margin of the Arabian Plate is presented. Two stratigraphic sections (Jarhum and Qazi, respectively) compare the depositional dichotomy between crest and flank. The palaeohigh Jahrum section documents a deepening upward succession that includes brackish carbonates at the base, followed by shallow–marine carbonates, and culminates in basinal deposits. The sedimentary record of Santonian deposits in the Qazi section (flank) comprises stratigraphically thick calciturbidites, calcidebrites, slump folding, clinoforms, and channel-fill deposits, which conformably overlie deep-water deposits. This case study provides insights into processes that are rarely documented in the Tethyan realm. Data shown here exemplify the interaction between regional uplift (related to tectonic inversion) and eustatic sea–level changes. The regional correlation of the facies architecture highlights important lateral variations in facies and stratigraphic thickness controlled by bathymetry and seafloor inclination related to the geometry of the palaeohigh. We suggest that the redeposited carbonates described here are characteristic of tectonically active intervals along slope settings. Furthermore, we demonstrate that sustained carbonate production on unrimmed, distally steepened ramps supports the deposition of calciclastics. The data presented are crucial for understanding redeposition processes in Cretaceous carbonate systems along the Arabian margin and beyond.</div></div>","PeriodicalId":21575,"journal":{"name":"Sedimentary Geology","volume":"486 ","pages":"Article 106943"},"PeriodicalIF":2.9,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144809661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sea-level controls on terrigenous sediment input to deep water of the Pearl River margin since the last glacial maximum","authors":"Kun Qi ,&nbsp;Chenglin Gong ,&nbsp;Katrine Juul Andresen ,&nbsp;Yang Zhou ,&nbsp;Yibo Geng ,&nbsp;Massine Bouchakour","doi":"10.1016/j.sedgeo.2025.106939","DOIUrl":"10.1016/j.sedgeo.2025.106939","url":null,"abstract":"<div><div>Glacio-eustatic sea-level changes since the Last Glacial Maximum (LGM) have been frequently regarded as the primary driver of terrigenous input to deep-water settings of marginal sea basins. However, on those continental margins where shelf edges lie at water depths farther exceeding 120 m, whether and how eustatic sea-level changes since the LGM have controlled terrigenous sediment input to deep water remains a topic of considerable interest. Taking the Pearl River margin that has a shelf edge with average water depth of 250 m as the study area, we use the depositional records of two piston cores on the head and mouth of a submarine canyon to reconstruct the history of terrigenous input to deep water since the LGM. We then relate the variations of terrigenous input to the contemporary eustatic sea-level changes to examine the details of the role of sea-level changes on terrigenous input. The results indicate that since the LGM there was a three-stage temporal evolution of terrigenous input to deep water on the Pearl River margin. During glacial, deglacial, and interglacial periods, terrigenous input were respectively high, decreasing, and low, correlating well with sea-level lowstands, sea-level rising, and sea-level highstands. Such tight coupling strongly suggests that glacio-eustatic sea-level changes since the LGM could still control terrigenous input to deep water on the Pearl River margin. Specifically, after the LGM, the first rapid sea-level rise, occurred in the periods of Heinrich Stadial 1 (HS1) and Bølling-Allerød (B-A), dramatically inundated the shelf, shifted the shoreline landward and thus, caused a millennial-scale drop of terrigenous input. Within the interglacial period, the sea level had risen almost to its present level and remained relatively stable, during which fluctuations in East Asian Monsoon (EAM) might have an influence on terrigenous input. Therefore, within the interglacial period, terrigenous input, though generally having low levels, showed a slight fluctuation correlated well with the changes of monsoonal climates. This study deepens our knowledge on the fundamental role of sea-level changes in sediment dispersal systems and provides implications for understanding deep-sea dynamics, especially within the context of a continental margin where shelf edges are found at much greater water depths and climatic conditions are rapidly changing.</div></div>","PeriodicalId":21575,"journal":{"name":"Sedimentary Geology","volume":"486 ","pages":"Article 106939"},"PeriodicalIF":2.9,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144748723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 Miocene sedimentary cover of the Mula-Gebas Basin: Internal-External Zone Boundary of the Betic Cordillera, South Spain","authors":"Francesco Perri ,&nbsp;Sara Criniti ,&nbsp;Francesco Cavalcante ,&nbsp;Manuel Martín-Martín ,&nbsp;Antonio Sánchez-Navas ,&nbsp;Salvatore Critelli","doi":"10.1016/j.sedgeo.2025.106924","DOIUrl":"10.1016/j.sedgeo.2025.106924","url":null,"abstract":"<div><div>The Sierra Espuña and the Mula-Gebas intramontane basin, SE Spain, represent the Internal-External Zone Boundary (IEZB) of the eastern Betic Cordillera. The Miocene infill of this basin seals the IEZB and is mainly derived from the Internal Zone. This deposition is coeval with a Late Miocene volcanism. Therefore, the study of these sediments is crucial for the source-area provenance, sorting and recycling, paleoclimate, weathering, unroofing and tectonic processes, during the intramontane basins developing of the western peri-Mediterranean Chains. Sandstone detrital modes, and mineralogical and chemical compositions of mudrocks were arranged in two sedimentary cycles: (1) the middle Burdigalian-early Langhian, and (2) the middle Tortonian-early Messinian. The quartzolithic to feldspathic lithoarenites infer the erosion from a lithic-transitional recycled to transitional-quartzose recycled orogen, since low-medium grade metamorphic lithics and rare coeval volcanics with andesitic, andesitic-dacitic and rhyodacitic-rhyolitic sources are present. The mudrocks reveal a felsic (granitic-gneiss) source with a minor mafic input in the Upper Miocene. A shallow burial history and low thermal conditions (&lt;∼50 °C) has been also evidenced. Moreover, the paleoclimate changed from warm and/or wet during the Middle Miocene to cold/arid in the Late Miocene.</div></div>","PeriodicalId":21575,"journal":{"name":"Sedimentary Geology","volume":"486 ","pages":"Article 106924"},"PeriodicalIF":2.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144338611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aeolian–fluvial interactions within a fault-controlled basin: Late Cretaceous Chaling Basin, South China","authors":"Xiaocan Yu ,&nbsp;Chunlian Wang ,&nbsp;Gabriel Bertolini ,&nbsp;Claiton Marlon dos Santos Scherer ,&nbsp;Adriano Domingos dos Reis ,&nbsp;Nigel P. Mountney","doi":"10.1016/j.sedgeo.2025.106926","DOIUrl":"10.1016/j.sedgeo.2025.106926","url":null,"abstract":"<div><div>The Upper Cretaceous Daijiaping Formation of the Chaling Basin, southeast China, is a mixed aeolian–fluvial succession accumulated in an erg-margin setting. The roles of climate and tectonics in governing the temporal and spatial arrangement of aeolian and fluvial strata are investigated using lithofacies and architectural-element analyses of outcrops in the eastern part of the basin. Architectural elements of aeolian origin record the preserved expression of dunes, sandsheets, damp and wet interdunes, and sand pods. Architectural elements of alluvial origin record channelized bedload streams and cobble-sand sheetflow units. Distinctive deflation lags and desert pavements are also recognized. The alternating nature of deposition via aeolian and aqueous processes is marked by a series of sand-drift surfaces that form a record of repeated shifts from aeolian to water-lain depositional conditions. Ephemeral water influx to the desert-margin system likely occurred in response to exceptional rainfall caused by monsoonal water discharge and meltwaters from glaciated mountain ranges that bordered the basin. The vertical arrangements of alternating facies associations define stacked wetting-upward cycles, each 0.4–14.2 m thick. Each cycle commences with simple or compound crescentic dune deposits, else with aeolian sandsheet deposits. These are overlain by bedload stream or conglomerate sheetflow deposits. The vertical stacking of these different architectural elements records the contraction and expansion of erg-margin systems in response to climate-controlled variations in the groundwater level, sand availability for aeolian transport, and fluvial and aeolian sediment transport capacity. The stratigraphic evolution was controlled by exceptional rainfall events at the basin margin, consequent floods into the dune-field margin and associated fluctuations in the water-table level. Orogenic uplift, a subtropical high-pressure system, and a variable groundwater level controlled by a monsoon climate and tectonic subsidence resulted in the development of extensive aeolian desert depositional systems in the South China hinterland during the Late Cretaceous.</div></div>","PeriodicalId":21575,"journal":{"name":"Sedimentary Geology","volume":"486 ","pages":"Article 106926"},"PeriodicalIF":2.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144518052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transgressive vs. forced regressive peat accumulation: Response of fluvial-apron peatland floodplains to aggradational transgression vs. forced regression","authors":"Jincheng Liu ,&nbsp;Yan Zhang ,&nbsp;Jingqiang Tan ,&nbsp;Daiyong Cao","doi":"10.1016/j.sedgeo.2025.106935","DOIUrl":"10.1016/j.sedgeo.2025.106935","url":null,"abstract":"<div><div>Previous work suggests the possibility that peat accumulation during relative sea-level (RSL) fall may be more common in the Quaternary and geological records than is currently commonly assumed. We investigate this further based on sequence stratigraphic analysis of successive coal-bearing cyclothems from the North China Permo-Carboniferous cratonic basin. The results show that each cyclothem changes basinward from a purely fluvial sequence to a mixed marine–nonmarine sequence. It is bounded by maximum regressive surfaces, correlative paired regional composite scour and interfluvial exposure surfaces farther landward, and correlative combined wave-ravinement and maximum regressive surfaces farther basinward. Temporally, each cyclothem transitions from a transgressive through highstand to falling-stage systems tract directly followed by the transgressive systems tract of the next cyclothem without an intervening lowstand systems tract. Depending on geomorphic conditions and characteristics of RSL rise or fall, the downstream fluvial reaches during transgression can be dominated by fluvial-fan or delta-plain channel aggradation, estuarine valley degradation, or lagoonal or fluvial-apron floodplain aggradation, or they transition from one to another. The downstream fluvial reaches during forced regression typically transition from delta plain degradation-inclusive through strandplain grade to fluvial apron aggradation-sustainable. Peat accumulation can be sustained only in fluvial-apron peatland floodplains during aggradational transgression or aggradational forced regression. Forced regressive fluvial-apron floodplain coal seams typically exhibit an overall upward decrease in mineral, ash, inertinite and sporinite contents and groundwater index, along with an increase in vitrinite content, gelification, tissue preservation and vegetation indices. Reverse trends of these properties characterize transgressive fluvial-apron floodplain coal seams.</div></div>","PeriodicalId":21575,"journal":{"name":"Sedimentary Geology","volume":"486 ","pages":"Article 106935"},"PeriodicalIF":2.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144614166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Middle-Late Pleistocene to Holocene sediments of the Tremithos River and related shallow-marine to non-marine coastal deposits in SE Cyprus: Products of inter-related surface uplift and glacio-eustatic controlled sea-level change","authors":"Christina Antoniou,&nbsp;Alastair H.F. Robertson","doi":"10.1016/j.sedgeo.2025.106900","DOIUrl":"10.1016/j.sedgeo.2025.106900","url":null,"abstract":"<div><div>The Pleistocene development of the Tremithos River exemplifies interacting controls of fluvial and shallow-marine sedimentation. The overall driver was domal uplift of southern Cyprus, focused on the ophiolitic Troodos Massif. Middle-Upper Pleistocene fluvial sediments accumulated under the dominant influences of glacio-eustatic and related climatic changes. Early-Middle Pleistocene is preserved as remnant surfaces and rounded erosional hills. Late Pleistocene-Holocene saw pulsed incision that deepened and narrowed the channel, mainly in the upper reaches. Meanders developed in the middle reaches. A broad, shallow channel formed in the lower reaches, passing into a coastal plain and a broad delta, affected by cyclical marine transgressions and regressions. Following incision events, coarse, poorly sorted conglomerates accumulated under high-energy stream flow in a cool, wet climate, generally correlated with glacial periods. Channel fill was mainly achieved by more persistent, lower energy stream flow in semi-braided channels, coupled with overbank deposition. Common well-rounding of highly resistant lithologies (e.g. chert) within a c. 30 km-long river suggests some recycling from older terrace deposits. Chalky colluvium formed by slope wasting of nearby chalk and marl, mainly during cool, humid periods. Reddish terra rossa paleosols mainly record relatively warm, stable, humid periods. Bedrock lithologies (e.g. diabase, chert) exerted a strong influence on clast lithology and shape. Younger fluvial deposits are coeval with Holocene shallow-marine terrigenous sediments and carbonates (including solitary coral) in coastal areas. Some previously reported shallow-marine sands are reinterpreted as aeolianites. Locally, deposition was influenced by surface uplift along a near-coastal strike-slip fault, related to oblique convergence of the Africa-Eurasia plates.</div></div>","PeriodicalId":21575,"journal":{"name":"Sedimentary Geology","volume":"486 ","pages":"Article 106900"},"PeriodicalIF":2.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144562952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}