Marine Micropaleontology最新文献

{"title":"Unraveling ecological signals related to the MECO onset through planktic and benthic foraminiferal records along a mixed carbonate-siliciclastic shallow-water succession","authors":"Antonella Gandolfi ,&nbsp;Victor Manuel Giraldo-Gómez ,&nbsp;Valeria Luciani ,&nbsp;Michele Piazza ,&nbsp;Valentina Brombin ,&nbsp;Simone Crobu ,&nbsp;Cesare Andrea Papazzoni ,&nbsp;Johannes Pignatti ,&nbsp;Antonino Briguglio","doi":"10.1016/j.marmicro.2024.102388","DOIUrl":"10.1016/j.marmicro.2024.102388","url":null,"abstract":"<div><p>The shallow-water Capo Mortola succession (Liguria, NW Italy) yields diverse assemblages of smaller benthic and planktic foraminifera, larger benthic foraminifera (LBF), and calcareous nannofossils. With the aim of improving the understanding of the Middle Eocene Climatic Optimum (MECO) impact on the shallow-water marine biotic communities due to global warming, we provide biostratigraphic and stable isotope data to achieve a reliable stratigraphic constraint of the MECO. The correlation of the stable isotope oxygen data with datasets of similar age from other regions suggests that only the onset of the MECO interval is recorded in the Capo Mortola section. Quantitative analyses of smaller benthic foraminiferal assemblages indicate that the shallow-water setting of Capo Mortola was not particularly affected by the onset of the MECO perturbance because no variation in nutrient supply or oxygen level were detected. A different scenario is recorded by the LBF genera <em>Operculina</em> and <em>Discocyclina</em>, which increased in abundance across the MECO onset, probably due to a rise in temperature and adapting to the increase in nutrient supply. In the upper water column, the variations in calcareous plankton communities appear to be controlled by both the MECO warming and a moderate increase in eutrophic conditions related to the enhanced hydrological cycle. Nutrients, mostly consumed in the upper water column, reached the seafloor in a limited amount, as benthic foraminifera record a meso-oligotrophic environment across the studied MECO interval.</p></div>","PeriodicalId":49881,"journal":{"name":"Marine Micropaleontology","volume":"190 ","pages":"Article 102388"},"PeriodicalIF":1.5,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0377839824000586/pdfft?md5=ecfb46cdef8d0093e7374bc6c271258c&pid=1-s2.0-S0377839824000586-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141786116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Dissolved oxygen affinities of hundreds of benthic foraminiferal species","authors":"Martin Tetard,&nbsp;Joseph G. Prebble,&nbsp;Giuseppe Cortese","doi":"10.1016/j.marmicro.2024.102380","DOIUrl":"https://doi.org/10.1016/j.marmicro.2024.102380","url":null,"abstract":"<div><p>Over the past decades, fossil assemblages of benthic foraminifera have been used to reconstruct the variability of oxygen-depleted areas, including oxygen minimum zones. These areas currently represent almost a tenth of the global oceans' surface area, and further expansion is expected due to global warming; with major impacts on marine ecosystems, biodiversity, and fisheries. To predict their future evolution, accurate estimates and quantification of past oceanic oxygenation are needed, and thus consistent calibration of the <span><math><mfenced><msub><mi>O</mi><mn>2</mn></msub></mfenced></math></span> estimation transfer functions is required.</p><p>Here, we combine the BENFEP database that compiles all the benthic foraminiferal census data published for the East Pacific Ocean, with dissolved oxygen data interpolated from the WOA18 and GLODAPV2.2022 databases, to describe the oxygen affinities of the 1526 benthic foraminiferal taxa from the BENFEP database among 1691 samples. The affinities of the most common 202 species of the database are detailed here. For each of these taxa, the range of oxygen concentration, average <span><math><mfenced><msub><mi>O</mi><mn>2</mn></msub></mfenced></math></span> value where the species is usually found, and <span><math><mfenced><msub><mi>O</mi><mn>2</mn></msub></mfenced></math></span> value associated with its peak in relative abundance are listed and used to assign each taxon to the oxygen categories anoxic, dysoxic, suboxic, low oxic, and high oxic.</p><p>Finally, using the relative abundance of each of these five oxygen assemblages and their associated taxa, transfer function indices of dissolved oxygen estimation were refined. The new <span><math><msub><mi>BFA</mi><mi>ex</mi></msub></math></span> extends the range of applicability of the formerly published BFA index, here updated using all the available samples <span><math><mfenced><msub><mi>BFA</mi><mi>up</mi></msub></mfenced></math></span> and extended from 0.04 to 2.58 mL L⁻¹ to 0.02–6.62 mL L⁻¹.</p></div>","PeriodicalId":49881,"journal":{"name":"Marine Micropaleontology","volume":"190 ","pages":"Article 102380"},"PeriodicalIF":1.5,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141593606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Looking for the oldest diatoms","authors":"Karolina Bryłka ,&nbsp;Sylvain Richoz ,&nbsp;Andrew J. Alverson ,&nbsp;Daniel J. Conley","doi":"10.1016/j.marmicro.2024.102371","DOIUrl":"https://doi.org/10.1016/j.marmicro.2024.102371","url":null,"abstract":"<div><p>Paleontological observations of ancient flora and fauna provide powerful insights into past diversity and relationship dynamics between organisms and their environments. Diatoms are globally distributed protists that influence major biogeochemical cycles and sustain oceanic food webs. The fossil diatom record extends 120 million years back to the Early Cretaceous where rare deposits were discovered worldwide and are occasionally represented by diverse communities. However scarce, the taxonomic richness and geographical spread of these diatom communities suggest prior evolutionary events and therefore earlier deposits. To complement the existing fossil information and to discover diatom deposits predating 120 Ma, we examined 33 study sites from cores and outcrops across oceans and continents. These efforts did not generate new fossil discoveries, however. Our assessment suggests biogenic silica that comprises the cell wall of diatoms was likely dissolved from Mesozoic sediments through diagenetic processes. Altogether, the search for the oldest diatoms must continue but should target sediments that experienced shallow burial and concretions.</p></div>","PeriodicalId":49881,"journal":{"name":"Marine Micropaleontology","volume":"190 ","pages":"Article 102371"},"PeriodicalIF":1.9,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0377839824000410/pdfft?md5=6fb4afaf725fe8ef44eca7bedfea6dc3&pid=1-s2.0-S0377839824000410-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141290864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Phytoplankton and zooplankton paleocommunity change before and during the onset of the Lau Extinction Event (Ludlow, Silurian)","authors":"Robertas Stankevič ,&nbsp;Agnė Venckutė-Aleksienė ,&nbsp;Sigitas Radzevičius ,&nbsp;Andrej Spiridonov","doi":"10.1016/j.marmicro.2024.102368","DOIUrl":"https://doi.org/10.1016/j.marmicro.2024.102368","url":null,"abstract":"<div><p>The Ludlow epoch of the Silurian period was a time of significant geobiological perturbations, the most significant being the mid-Ludfordian Lau Event and associated huge positive carbon isotopic excursion. On the other hand, the impact of the Lau Event on ecosystems is far from understood, with the majority of studies being concentrated on conodonts, graptolites, and brachiopods. Therefore, here we present the high-resolution Gorstian to mid-Ludfordian Baubliai-2 core section record of the phytoplankton (acritarch and green algae) change from the deep shelfal facies belt of the Silurian Baltic Sedimentary Basin. Seven distinct phytoplankton assemblages are distinguished. The general feature of the assemblage change is an overarching trend toward higher relative abundances of the green algae disaster taxon <em>Leiosphaeridia</em> spp., which peaked during the Lau Event. The absolute abundance variability of the various components of the plankton including the hyper-abundant <em>Leiosphaeridia</em> spp. and <em>Tasmanites</em> spp. revealed the presence of consistent 0.93 Ma cyclicity. The diversity of phytoplankton is directly correlated with graptolite species diversity, which suggests common driving mechanisms of evolution for different components of the plankton community. The recurrence and joint recurrence plots and recurrence quantification analysis revealed a coordinated evolution of phytoplankton and graptolite diversities. The Lau Event interval stood out as a distinct coordinated low diversity state in both phytoplankton and in graptolites. Similar anomalous community states were previously detected in benthic communities (brachiopods), and in communities of pelagic predators (conodonts). Therefore, the current evidence suggests that the Lau Event had a significant impact across the whole range of communities and ecosystems.</p></div>","PeriodicalId":49881,"journal":{"name":"Marine Micropaleontology","volume":"189 ","pages":"Article 102368"},"PeriodicalIF":1.9,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141077845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rare bioerosion in large benthic foraminifera in the Eocene of NE Iran: Implications for global warming and trophic regime","authors":"Olev Vinn ,&nbsp;Mehdi Hadi ,&nbsp;Dangpeng Xi ,&nbsp;Mohsen Allameh","doi":"10.1016/j.marmicro.2024.102369","DOIUrl":"https://doi.org/10.1016/j.marmicro.2024.102369","url":null,"abstract":"<div><p>Bioerosion is rare in large benthic foraminifera (LBF) in the Eocene of Ziarat Formation, Iran. Three bioerosion ichnotaxa have been identified, including more common <em>Trypanites</em> isp. and <em>Entobia</em> isp., and rare <em>Meandropolydora sulcans</em>. The rare bioerosional traces in LBF tests support the scenario of an oligotrophic nutrient regime during the studied interval. The sedimentation rate may have also been among the controls on the bioerosion of LBF in the Middle Eocene of Iran, but the oligotrophic nutrient regime likely had a stronger effect. The bioerosion of LBF tests during the Middle Eocene Climatic Optimum (MECO) was rather low or at maximum moderate, suggesting that an oligotrophic nutrient regime could compensate for the increase in bioerosion caused by ocean acidification and warming.</p></div>","PeriodicalId":49881,"journal":{"name":"Marine Micropaleontology","volume":"189 ","pages":"Article 102369"},"PeriodicalIF":1.9,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141083228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to “Microbial-dominated dendrolites in the Zhangxia Formation of the Cambrian Miaolingian: A case study of the Dongping section, Shandong Province, eastern China” [Marine Micropaleontology 189 (2024) 102363]","authors":"Yidan Zhu ,&nbsp;Chaojia Mei ,&nbsp;Chung-Il Ri ,&nbsp;Xiaoqing Meng","doi":"10.1016/j.marmicro.2024.102367","DOIUrl":"https://doi.org/10.1016/j.marmicro.2024.102367","url":null,"abstract":"","PeriodicalId":49881,"journal":{"name":"Marine Micropaleontology","volume":"189 ","pages":"Article 102367"},"PeriodicalIF":1.9,"publicationDate":"2024-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0377839824000379/pdfft?md5=a8a0a3dab82af9afe61c96039ab83a7c&pid=1-s2.0-S0377839824000379-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140638730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Response of the calcareous nannofossils to the Cretaceous-Paleogene boundary event: A case study from Sinai, Egypt","authors":"Amr A. Metwally ,&nbsp;Azza A. Mohamed ,&nbsp;Nageh A. Obaidalla ,&nbsp;Abdelhamid M. Salman ,&nbsp;Kamel H. Mahfouz","doi":"10.1016/j.marmicro.2024.102366","DOIUrl":"https://doi.org/10.1016/j.marmicro.2024.102366","url":null,"abstract":"<div><p>A detailed study of calcareous nannofossils was conducted on a well-exposed succession encompassing the Cretaceous-Paleogene (K-Pg) boundary interval at Wadi Nukhul, Sinai, Egypt, as a part of the southern Tethyan margin. The nannofossil biostratigraphic data show that the Nukhul succession sustains a complete K-Pg boundary interval. The nannofossil assemblage indicates a shift from cool/oligo-mesotrophic conditions in the late Maastrichtian <em>Micula murus</em> Zone to warm/oligotrophic in the latest Maastrichtian <em>M. prinsii</em> Zone prior to the K-Pg boundary. At the K-Pg boundary, diversity, and total abundance of the calcareous nannofossils remarkably decreased signifying unstable marine conditions. The post-impact assemblage (lowermost part of NP1 Zone) was marked by acme of <em>Cervisiella operculata</em> indicating oligotrophic conditions in the photic zone related to the diminished of the marine primary producers in the lowermost Danian. At the upper portion of the NP1 Zone, the assemblage is still dominated by <em>C. operculata</em>, besides the successive occurrence of the small-sized incoming Paleocene taxa <em>Biantholithus sparsus</em> and <em>Neobiscutum romeinii</em>. This pattern was accompanied by increased frequencies of <em>Zeugrhabdotus sigmoides</em> indicating stressful cool/meso-eutrophic surface water conditions signify the initial recovery interval. Upward in the early Danian NP2-NP3 zones, the nannofossil species diversity and total abundance progressively increased. Also, the nannofossil assemblage characterized by the existence of the new Paleocene oligotrophic indicators like <em>Cruciplacolithus primus</em>, <em>Coccolithus pelagicus</em>, and <em>Ericsonia subpertusa</em>. This probably indicates a tendency toward rebuilding of the biological pump efficiency and, therefore, a full recovery phase was resumed.</p></div>","PeriodicalId":49881,"journal":{"name":"Marine Micropaleontology","volume":"189 ","pages":"Article 102366"},"PeriodicalIF":1.9,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140559030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Upper Ocean variations at IODP Hole U1505C in the northern South China Sea and their response to the East Asian Monsoon during the middle Miocene","authors":"Yamin Lu,&nbsp;Baoqi Huang","doi":"10.1016/j.marmicro.2024.102365","DOIUrl":"https://doi.org/10.1016/j.marmicro.2024.102365","url":null,"abstract":"<div><p>We used the samples from International Ocean Discovery Program (IODP) Hole U1505C in the northern South China Sea (SCS) to reconstruct the upper ocean profiles and discussed the East Asian Monsoon (EAM) variations during 15.0–12.5 Ma. 15 genera and 41 species were identified, and 7 planktonic foraminifer datums were recognized, then a reliable chronostratigraphic framework was updated. A principal component analysis (PCA) was used to identify the suitable assemblages for reconstructing upper water profiles, based on planktonic foraminifera relative abundance and isotope records. The sea surface temperature (SST), paleo-productivity, and the depth of thermocline (DOT) were reconstructed by the content of warm water species, high productivity species, and the ratio of mixed layer to thermocline species, respectively. Three main phases were identified: (1) during 15.0–14.7 Ma, the SST and paleo-productivity were high, while the thermocline was shallow, indicating a warm and rainy climate influenced by East Asian Summer Monsoon (EASM); (2) during 14.7–13.8 Ma, the SST was lower, the paleo-productivity increased significantly, and the thermocline deepened, indicating an enhanced East Asian Winter Monsoon (EAWM); (3) during 13.8–12.5 Ma, the SST increased slightly, the paleo-productivity deceased, while the DOT showed neglectable change, indicating a stable EAWM and a waning EASM. The results of the Morlet wavelet spectrum revealed that EAM and the upper ocean profiles in the northern SCS were predominantly regulated by the eccentricity cycles, emphasizing the significant impact of low-latitude processes on climate variations.</p></div>","PeriodicalId":49881,"journal":{"name":"Marine Micropaleontology","volume":"189 ","pages":"Article 102365"},"PeriodicalIF":1.9,"publicationDate":"2024-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140638729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microbial-dominated dendrolites in the Zhangxia Formation of the Cambrian Miaolingian: A case study of the Dongping section, Shandong Province, eastern China","authors":"Yidan Zhu ,&nbsp;Chaojia Mei ,&nbsp;Chung-Il Ri ,&nbsp;Xiaoqing Meng","doi":"10.1016/j.marmicro.2024.102363","DOIUrl":"https://doi.org/10.1016/j.marmicro.2024.102363","url":null,"abstract":"<div><p>Nonlamellar dendrolites, a type of microbial carbonate, exhibit dendritic fabric on the macroscale, which is different from stromatolites, thrombolites, and leiolites. This work reports the sedimentary environment and sedimentary characteristics of dendrolites dominated by calcified microbes in the Zhangxia Formation in the Dongping section of Shandong Province, China. Thick oolitic limestone affected by the rise in sea level is developed in the middle section of the Zhangxia Formation in the Dongping section, and a set of thick massive dendrolites are developed above the oolitic limestone. It exhibits the special sedimentary phenomenon of microbes seeking stability in a high-energy environment. Microscopically, the dendrolites are characterized by the rich development of calcified cyanobacteria fossils, such as the epiphyton group and <em>Girvanella</em>, demonstrating the diversity and complexity of the microbes that dominate the dendrolite formation in the Dongping section. The epiphyton group can be classified by morphological characteristics, namely, <em>Epiphyton</em>, <em>Korilophyton</em>, and <em>Hedstroemia</em>. The latter can be further categorized into typical <em>Hedstroemia</em> and <em>Cayeuxia</em>. Therefore, this study enhances our understanding of dendrolite sedimentary environments and provides a reference example for exploring diverse fossil records in ancient strata.</p></div>","PeriodicalId":49881,"journal":{"name":"Marine Micropaleontology","volume":"189 ","pages":"Article 102363"},"PeriodicalIF":1.9,"publicationDate":"2024-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140540488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Beyond biostratigraphy: Conodont matters in evolving planetary scenarios","authors":"Annalisa Ferretti ,&nbsp;Guillermo L. Albanesi ,&nbsp;Xavier Crosta ,&nbsp;Ric W. Jordan","doi":"10.1016/j.marmicro.2024.102364","DOIUrl":"https://doi.org/10.1016/j.marmicro.2024.102364","url":null,"abstract":"","PeriodicalId":49881,"journal":{"name":"Marine Micropaleontology","volume":"189 ","pages":"Article 102364"},"PeriodicalIF":1.9,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140543454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}