Depositional Record最新文献

{"title":"South American Great Basin: Limnogeological analysis of the Salina del Bebedero Basin, Argentina (Late Pleistocene-recent)","authors":"Eimi Ailen Font,&nbsp;Jorge O. Chiesa,&nbsp;David E. Traverso","doi":"10.1002/dep2.70000","DOIUrl":"https://doi.org/10.1002/dep2.70000","url":null,"abstract":"<p>The Bebedero tectonic depression in San Luis province, Argentina, is a closed drainage basin that has formed as a result of block-faulting and rifting processes. The Bebedero lake exhibits notable similarities to the endorheic watersheds of the western United States, particularly those of Death Valley, the Saline Valley and, to a lesser extent, the Great Salt Lake. While it is currently classified as a playa lake, there is evidence of lake levels near the sill that overflowed during the Late Pleistocene. Several lines of evidence suggest that climate is the major controlling factor in the basin's fill. The Salina del Bebedero Basin is an underfilled lake basin type, particularly a discharge lake basin. This assertion is supported by recent findings, including precise topography, stratigraphy, facies associations, radiocarbon ages and palaeontology from one section and two transects. The following presentation comprises stratigraphic correlations, palaeoenvironmental reconstructions and a graphical model of lake stages based on these new results and previously published research. This paper provides a model of lake-level fill from the Late Pleistocene to the present, identifying distinct highstands and lowstands associated with global climate events. The surface and depth of the lake were reconstructed for each stage. The maximum expansion was estimated at 1000 km² during the Pre-Last Glacial Maximum and 782.6 km² during the Last Glacial Maximum, with depths ranging from 60 to 75 m. Lake Bebedero exhibited similar lake-level responses to climate variations as Lake Bonneville, Great Salt Lake, as well as sub-environmental similarities with Death Valley and the Saline Valley. In addition to its palaeoclimate significance, Lake Bebedero has archaeological records of an early settlement dating back <i>ca</i> 10 to 6 cal ka BP. The scarcity of data concerning the early human settlement in southern South America makes archaeological evidence relevant. Therefore, the inferences regarding climate and environment derived from studies of the lake provide important information about the first human groups to populate these regions.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"11 2","pages":"739-763"},"PeriodicalIF":1.9,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.70000","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143846204","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":"Multi-sequential order transgressive cycles from the last interglacial to the Holocene revealed by deep-core sediment facies analysis in the Baeksu tidal deposits, south-west coast of Korea","authors":"Serin Lim,&nbsp;Jin Cheul Kim,&nbsp;Dhongil Lim,&nbsp;Yongmi Kim,&nbsp;Tae Soo Chang","doi":"10.1002/dep2.70002","DOIUrl":"https://doi.org/10.1002/dep2.70002","url":null,"abstract":"<p>High-resolution sequence analysis of three drill-cores with well-constrained optically simulated luminescence ages reveals a stratigraphic evolution of the Baeksu tidal flat (south-west coast of Korea) that documents the development of tide-dominated estuary infill interacting with minimal fluvial processes since marine isotope stage 6. The stratigraphic architecture and its correlation along an upper mudflat-to-subtidal transect showcase two different hierarchies of sequences and small-scale (fifth-order) subsequences that are nested within larger-scale (fourth-order) sequences. Two fourth-order sequences with a frequency of 100 kyr consist of lower fluvial deposits and overlying tidal deposits, respectively, reflecting a twofold regressive–transgressive sedimentary sequence related to glacial–interglacial cycles. The sequence boundary is marked by an abrupt facies change from oxidised spit gravels (marine isotope stage 3) to tidal muds (marine isotope stage 1). An interesting feature is the presence of two packages of retrograding spit/tidal deposits corresponding to marine isotope stage 5a/b and marine isotope stage 3 interstadials deposited during short-lived sea-level rise, in spite of the long-term phase of glacial sea-level fall spanning from marine isotope stage 5d to marine isotope stage 2. Identification of deeply oxidised tidal deposits dated to marine isotope stage 5a/b confirms that two short-term fluctuations in sea level occurred during the long-lived glacial period. Such nested successions are assigned as fifth-order subsequences with 40 kyr time intervals. The late Quaternary Baeksu tidal flat succession was thus mainly controlled by two different frequencies and magnitudes of sea-level changes, associated with major interglacials (marine isotope stage 5e and 1) and minor interstadials (marine isotope stage 5a and 3). More importantly, transgressive episodes are significantly better preserved than regressive phases. This study provides a good example of how multi-order, multiple transgressive deposition may be preserved in a tide-dominated estuarine setting, particularly where river inputs are negligible.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"11 2","pages":"764-785"},"PeriodicalIF":1.9,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.70002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143846024","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":"Seasonal lake-to-air temperature transfer functions derived from an analysis of 1395 modern lakes: A tool for reconstructing air temperature from proxy-derived lake water temperature","authors":"Alexa Terrazas,&nbsp;Nathan Hwangbo,&nbsp;Alexandrea J. Arnold,&nbsp;Robert N. Ulrich,&nbsp;Aradhna Tripati","doi":"10.1002/dep2.326","DOIUrl":"https://doi.org/10.1002/dep2.326","url":null,"abstract":"<p>Lacustrine palaeotemperature reconstructions are important for characterising past temperature and hydroclimate change, validating multi-proxy reconstructions and evaluating global climate models. In particular, lake water temperature is often derived from geochemical proxies—including clumped isotopes (Δ₄₇), oxygen isotopes (δ¹⁸O), alkenone lipids (U^k’₃₇) and GDGT compounds (TEX₈₆). However, global climate models, constrained by resolution, computational demand and cost, are designed to simulate large-scale processes, often at the expense of resolving lakes and simulating lake temperature. Consequently, this limitation complicates the comparison of climate model-simulated variables such as air temperature, with lake water temperature or with other proxy variables (e.g. pollen-derived air temperature), and requires the use of a transfer function to relate lake temperature to air temperature. Previous work developed transfer functions to translate proxy-derived seasonal lake water temperature to mean annual air temperature using ground-based measurements from 88 lakes. This study reports new lake-to-air temperature transfer functions (for annual, spring through summer, spring, summer and warmest month) that incorporate lake surface water temperature, and new variables including latitude and elevation, by analysing climate reanalysis data and long-term satellite observations of surface temperatures for 1395 modern lakes via regression-based inverse modelling. With the use of multiple regression models and a dataset roughly 10 times larger, the error in predictions of mean annual air temperature is reduced by up to 48% compared to previous work. To demonstrate the potential of the new transfer functions for integrating and comparing proxy data with model output, Pliocene and Pleistocene mean annual air temperature was reconstructed from Δ₄₇-derived lake temperatures and compared with model simulations for the Last Glacial Maximum and mid-Piacenzian warm period. The new transfer functions, with reduced error, should enable more accurate palaeotemperature reconstructions from proxy-derived lake water temperature and allow for more comprehensive assessments of climate model skill.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"11 2","pages":"718-738"},"PeriodicalIF":1.9,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.326","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143846077","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":"Sedimentology and reservoir characterisation of Lower Jurassic clastic sedimentary rocks, Salt and Trans Indus Ranges, Pakistan: Evidence from petrography, scanning electron microscopy and petrophysics","authors":"Salman Ahmed Khattak,&nbsp;Nasar Khan,&nbsp;Waseem Khan,&nbsp;S. Sahaya Jude Dhas,&nbsp;George Kontakiotis,&nbsp;Ihtisham Islam,&nbsp;Hammad Tariq Janjuhah,&nbsp;Assimina Antonarakou","doi":"10.1002/dep2.325","DOIUrl":"https://doi.org/10.1002/dep2.325","url":null,"abstract":"<p>In this study, sandstones of the Lower Jurassic Datta Formation in the Salt and Trans-Indus ranges are investigated regarding composition, diagenesis, provenance and reservoir properties using petrography, scanning electron microscopy and petrophysical analysis. The detrital mineral composition of the Datta Formation indicated that the sandstones are quartzose, lithic-quartzose, lithic-feldspatho-quartzose, lithic-quartzo-feldspathic, quartzo-lithic and feldspatho-quartzose, primarily from the recycled orogen setting, including the Malani Igneous Suite, the Aravali Range and Nagar Parkar. The Datta Formation has sub-angular to well-rounded, fine to coarse and moderate to well-sorted grains. Numerous diagnostic processes that occurred in the early to late stages of diagenesis, such as compaction, pressure solution, cementation, alteration, dolomitisation and dissolution, are supported by evidence in the Datta Formation. Dissolution, physical compaction, dolomitisation and alteration enhanced the reservoir quality, while pressure solution and cementation reduced the reservoir quality of the Datta Formation. The porosity types detected in the Datta Formation under scanning electron microscopy are vuggy, intracrystalline/intraparticle, dissolution and intercrystalline, with an average petrographic visual porosity of 11%. The petrophysical aspects of the Datta Formation in the Chonai-01 well and the correlation between four wells indicated that the hydrocarbons had shifted up-dip towards the Isa-Khail-01 well, so it is recommended for drilling because of the greater depositional thickness. The comparison of the Datta Formation with age-equivalent units in other regions of eastern Tethys provided a better understanding of reservoir heterogeneities that can be applicable in areas with similar geological conditions for future petroleum exploration.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"11 2","pages":"698-717"},"PeriodicalIF":1.9,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.325","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143846093","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":"Mixed clastic-carbonate lake margin systems: An example from the Triassic of East Greenland","authors":"Steven D. Andrews,&nbsp;Li Guo","doi":"10.1002/dep2.324","DOIUrl":"https://doi.org/10.1002/dep2.324","url":null,"abstract":"<p>Lake margin deposits are the subject of increased study, but this is often focussed on either clastic or carbonate/microbial dominated end members. This study examines the interaction of clastic and carbonate systems. The Upper Triassic Edderfugledal Formation in East Greenland provides superb exposures through a carbonate dominated lacustrine succession. Fluctuations in lake level, interpreted as a response to cyclic, orbitally forced, climatic variance resulted in a highly mobile lake shore zone. The response of the shore zone environment to these fluctuations in lake level, and the interaction of both clastic and carbonate components, are documented in this study. A general trend from more arid to more humid conditions is recognised through the Edderfugledal Formation. This trend is reflected in a transition from more ephemeral lacustrine conditions with low sediment input to conditions where lacustrine episodes were more prolonged and clastic input was increased. Deposits reflecting more ephemeral conditions are dominated by extensive post-depositional disruption including desiccation, pedogenic processes and evaporite precipitation. These effects increase towards the lake margins where exposure was most common and most prolonged. Increasingly humid conditions and the associated longer-lived lacustrine developments and increased clastic sediment input resulted in a very different form of lake margin. During transgressive phases sediment input was pushed back to the lake margin allowing extensive microbialite development. Ooidal shoals developed in shallow water beyond the extent of clastic input. The lakeward migration of the ooidal shoals and the progradation of clastic systems eventually stifled the microbialites prior to the next transgressive event. In a mixed clastic-carbonate lacustrine setting the interaction of sediment supply and production are key factors in governing facies development and these are in turn predominantly controlled by lake-level change and lake margin bathymetry.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"11 2","pages":"675-697"},"PeriodicalIF":1.9,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.324","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143846137","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":"Interglacial dust, ocean fertilisation and Neoproterozoic earth oxygenation","authors":"Leandro G. DaSilva,&nbsp;Peir K. Pufahl,&nbsp;Noel P. James","doi":"10.1002/dep2.323","DOIUrl":"https://doi.org/10.1002/dep2.323","url":null,"abstract":"<p>Feedback processes that drove Earth's second major increase in ocean–atmosphere oxygen levels during the Neoproterozoic are poorly constrained. Variability in seawater redox over geological timescales is commonly linked to changes in the biogeochemical cycling of P and thus the rate of primary production and generation of photosynthetic oxygen. In the modern surface ocean, an important source of bioessential P and micronutrients (Fe, Cu, Co, Zn, Mo, Cr and Ni) is aeolian dust derived from deserts and arid, post-glacial landscapes. It is interpreted herein that glacial retreat following the Sturtian (<i>ca</i> 717 to 660 Ma) and Marinoan (<i>ca</i> 650 to 635 Ma) snowball glaciations provided copious dust to the global ocean. Correlation of interglacial siltstone successions in palaeogeographical context suggests that such dust accumulation was diachronous and concentrated in the palaeo-horse latitudes (30° N and 30° S). Delivery of this dust from continents is likely reflected in the steep increase in global radiogenic Sr isotope values (⁸⁷Sr/⁸⁶Sr) in post-Sturtian carbonates, and changes in the δ¹⁸O signatures of Cryogenian zircons derived from subducted marine sediments. Accumulation of sedimentary organic matter also peaked during interglacial periods, suggesting a causal link between glaciation, aeolian dust and primary production. This relationship implies windblown dust was an important source of P and micronutrients for an evolving biological pump that stimulated primary production, enhanced burial of organic carbon and increased ocean–atmosphere oxygen concentrations. Thus, delivery of aeolian dust to the global ocean was likely critical for sustaining Earth's second major increase in oxygen. Sequestration of atmospheric CO₂ in organic-rich siltstones and shales is also interpreted to have been an important negative feedback process, which together with silicate weathering, prevented runaway greenhouse conditions during interglacial periods. The oxygen produced by this aeolian marine biological pump may have helped pave the way for the evolution of multicellular animals in the Ediacaran.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"11 2","pages":"654-674"},"PeriodicalIF":1.9,"publicationDate":"2024-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.323","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143845979","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":"Smithian–Spathian carbonate geochemistry in the northern Thaynes Group influenced by multiple styles of diagenesis","authors":"Jordan P. Todes,&nbsp;Franziska R. Blattmann,&nbsp;Torsten Vennemann,&nbsp;Elke Schneebeli-Hermann,&nbsp;Hugo Bucher,&nbsp;Dan P. Razionale,&nbsp;Clara L. Blättler","doi":"10.1002/dep2.321","DOIUrl":"https://doi.org/10.1002/dep2.321","url":null,"abstract":"<p>The Smithian–Spathian boundary interval is characterised by a positive carbon isotopic excursion in both δ¹³C_carb and δ¹³C_org, concurrent with a major marine ecosystem reorganisation and the resurgence of microbialite facies. While these δ¹³C records have been traditionally interpreted as capturing global carbon cycle behaviour, recent studies have suggested that at least some excursions in early Triassic δ¹³C values may incorporate influences from authigenic or early diagenetic processes. To examine the mechanistic drivers of Smithian–Spathian boundary geochemistry, the carbonate geochemistry of a core from Georgetown, Idaho (USA), was analysed using a coupled δ^44/40Ca, δ²⁶Mg and trace-metal framework. While the δ¹³C record in the Georgetown core is broadly similar to other Smithian–Spathian boundary sections, portions of the record coincide with substantial shifts in δ^44/40Ca, δ²⁶Mg and trace-metal compositions that cannot feasibly be interpreted as primary. Furthermore, these geochemical variations correspond with lithology: The δ¹³C record is modulated by variations in the extent of dolomitisation, and the diagenetic styles recognised here coincide with individual lithostratigraphic units. A primary shift in local sea water δ¹³C values is inferred from the most geochemically unaltered strata, from <i>ca</i> 3‰ in the middle Smithian to <i>ca</i> 5‰ in the early Spathian, although the timing and pathway through which this occurs cannot be readily identified nor extrapolated globally. Therefore, the Georgetown core may not directly record exogenic carbon cycle evolution, showing that there is a need for the careful reconsideration of the Smithian–Spathian boundary—and more broadly, Early Triassic—geochemical records to examine potential local and diagenetic influences on sedimentary geochemistry.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"11 2","pages":"616-636"},"PeriodicalIF":1.9,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.321","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143845862","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":"Evidence for subsidence rate variation in the Newark Basin and its influence on the deposition of fluvial sediments of the Stockton Formation","authors":"Jane L. Alexander,&nbsp;Sean T. Thatcher,&nbsp;Jay Tobon,&nbsp;Victoria Rivelli","doi":"10.1002/dep2.322","DOIUrl":"https://doi.org/10.1002/dep2.322","url":null,"abstract":"<p>The Stockton Formation of the Newark Basin represents an exciting time in Earth history during the early stages of rifting of the North Atlantic, with rapid subsidence and sediment deposition. Much of the previous work on this formation has been done using drill cores, with development limiting surface exposure. While this allows us to build a full stratigraphic sequence of deposition, it has the potential to miss smaller-scale variability and sedimentary structures. It is also difficult to understand the three-dimensional geometries, architecture and relationships between the depositional elements from drill core alone. An outcrop in North Bergen, NJ that was recently exposed during construction provided an opportunity to study the primary and secondary sedimentary structures of a previously hidden part of the Stockton Formation. These sediments and structures were investigated in the field and laboratory, with geochemical data assisting in the interpretation of their origin and history. Despite its small size, this outcrop provides strong evidence for varying rates of basin subsidence, with rocks deposited during more rapid subsidence also showing secondary structures associated with major earthquakes. Rapid subsidence during fluvial deposition resulted in the preservation of more fine-grained, lower-porosity sediments. Recently the Newark Basin has been identified as having characteristics that are favourable for CO₂ storage, however, a detailed understanding of sedimentary lithologies is essential to assessing that potential. If these periods of rapid subsidence have similar lithological consequences basin-wide, this could potentially impact the capacity for carbon sequestration, by reducing porosity and permeability in many areas, and potentially creating barriers to flow.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"11 2","pages":"637-653"},"PeriodicalIF":1.9,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.322","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143845863","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":"Coming to light: How effective are sediment gravity flows in removing fine suspended carbonate from reefs?","authors":"Jaco H. Baas,&nbsp;William Hewitt,&nbsp;Stephen Lokier,&nbsp;James Hendry","doi":"10.1002/dep2.319","DOIUrl":"https://doi.org/10.1002/dep2.319","url":null,"abstract":"<p>Coral reefs are hard calcified structures, mainly found in warm tropical water. These ecosystems serve important roles as, for example, a source of food, shelter and nursery for different organisms, and in coastal protection. Reef-building organisms have evolved to inhabit a narrow ecological niche and thus are particularly susceptible to rapid changes in their environment, for example, under predicted climate-change scenarios. Anthropogenic climate change is widely accepted as the leading cause of rising ocean temperatures, sea water acidity and sedimentation rate, which all affect a coral's productivity, health and, to some extent, skeletal strength. High-energy weather events, such as storms and hurricanes, can erode reefs, thereby increasing the amount of suspended sediment and consequently the turbidity of the water. The removal of suspended sediment from the reef is vital for the health of reef producers, and a natural process that removes suspended sediment from reefs are sediment gravity flows. A key factor that controls the ability of sediment gravity flows to transport sediment is cohesion, as cohesion determines the run-out distance of a flow through changes in its rheological properties. This study examines the cohesive nature of sediment gravity flows laden with fine-grained CaCO₃. These gravity flows laden with mud-grade calcite are compared with flows carrying non-cohesive, silt-sized, silica flour, weakly cohesive kaolinite clay and strongly cohesive bentonite clay, by means of laboratory experiments. The results of these experiments show that the mud-grade calcite flows behave more akin to the silica-flour flows by reaching maximum mobility at considerably higher volumetric suspended sediment concentrations (47% for silica flour and 53% for CaCO₃) than the kaolinite and bentonite flows (22% for kaolinite and 16% for bentonite). Fine CaCO₃ gravity flows can therefore be regarded as physically non-cohesive, and their high mobility may constitute an effective mechanism for removing suspended sediment from coral reefs, especially at locations where a slope gradient is present, such as at the reef front and forereef. However, biological cohesion, caused by ‘sticky’ extracellular polymer substances produced by micro-organisms, can render mud-grade calcite cohesive and sediment gravity flows less mobile. The present study should therefore be seen as a first step towards a more comprehensive analysis of the efficiency of removal of suspended sediment from coral reefs.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"11 2","pages":"583-598"},"PeriodicalIF":1.9,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.319","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143845927","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":"Anatomy of modern sedimentary volcanoes produced by gas-charged groundwater liquefaction, Lake Powell, Hite, Utah: Implications for the recognition and interpretation of ancient sedimentary volcanoes","authors":"Michael C. Wizevich,&nbsp;Edward L. Simpson,&nbsp;Abigail Underwood,&nbsp;Laura Sherrod,&nbsp;Kelsey Livingston,&nbsp;Emily Bogner,&nbsp;Margariete Malenda","doi":"10.1002/dep2.320","DOIUrl":"https://doi.org/10.1002/dep2.320","url":null,"abstract":"<p>Numerous sedimentary volcanoes, recently exposed on the Colorado River delta surface at Lake Powell near Hite, Utah, were generated by sediment slurries propelled by gas, mainly microbially generated methane (CH₄). Two sedimentary volcanoes were excavated, one in 2016 and the other in 2019, in order to characterise the internal structures. Comparison of the internal structures of these features with those of previously documented seismic-generated sedimentary volcanoes helps in differentiating the various modes of mobilised sediment generation. Sedimentary volcanoes are commonly employed as tools in palaeoseismic reconstruction, thus it is important to establish criteria to differentiate non-seismic-generated sedimentary volcanoes and accompanying sediment deformation from those features generated by earthquakes. Trenches through the volcanoes and immediate subsurface areas reveal a complex cone stratigraphy of centimetre-scale graded sand-silt laminations and clastic dikes that cross-cut the cone and sub-cone (delta) sediment. Some cone strata have ripple cross laminations, a scoured base and are disrupted by soft-sediment deformation. In the 2016 volcano, the lowest 0.5 m of the dikes exposed in the trench are filled with organic-rich mud, but these conduits are empty nearer to the surface as a result of sediment settling after eruption cessation. The 2019 sedimentary volcano differs from the other by: (1) more cross laminations in the cone, (2) collapse structures surrounding the crater, (3) a relatively simple plumbing system assisted by desiccation-generated fissures and (4) a massive sediment infill of the vent. Both complex internal cone stratigraphy and the two distinct cross-cutting dike-conduit systems, unequivocally generated by recurrent gas and water discharge, add to the database of features for non-seismic-generated sedimentary volcanoes. This array of sedimentary structures from a non-seismic-generated sedimentary volcano demonstrates that certain features, including numerous internal laminations composing the cone and complex generations of dike systems are not unique to seismic-generated sand volcanoes.</p>","PeriodicalId":54144,"journal":{"name":"Depositional Record","volume":"11 2","pages":"599-615"},"PeriodicalIF":1.9,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/dep2.320","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143845956","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}