M. Buzas, L. Hayek, S. Culver, J. Murray, Daniel O. B. Jones
Within-habitat (α) diversity of living benthic foraminifera in the Atlantic Basin increases as latitude decreases and generally increases with depth from shelf to abyss. Total populations (live + dead) show the same pattern and indicate that species are becoming more widespread with increasing water depth. Thus, within-habitat diversity increases with depth while regional (or γ) diversity is greater on the shelf (more communities). Community structure analysis indicates stasis and growth in shallower areas with stasis or decline in the abyss. The latitudinal gradient has existed for ca. 34 Ma; lower latitude deeper habitats have the longest species durations. For living populations an inverse relationship between density and diversity suggests scarcity of food is not sufficient to decrease diversity through extinction. For shallower-dwelling species, variability of solar energy can explain the latitudinal gradient. For deep-sea species, energy transfer from the surface, along with environmental stability over vast expanses, are plausible explanations for high diversity.
{"title":"Oceanic-Scale Species Diversity of Living Benthic Foraminifera: Insights into Neogene Diversity, Community Structure, Species Duration, and Biogeography","authors":"M. Buzas, L. Hayek, S. Culver, J. Murray, Daniel O. B. Jones","doi":"10.2113/gsjfr.53.3.256","DOIUrl":"https://doi.org/10.2113/gsjfr.53.3.256","url":null,"abstract":"\u0000 Within-habitat (α) diversity of living benthic foraminifera in the Atlantic Basin increases as latitude decreases and generally increases with depth from shelf to abyss. Total populations (live + dead) show the same pattern and indicate that species are becoming more widespread with increasing water depth. Thus, within-habitat diversity increases with depth while regional (or γ) diversity is greater on the shelf (more communities). Community structure analysis indicates stasis and growth in shallower areas with stasis or decline in the abyss. The latitudinal gradient has existed for ca. 34 Ma; lower latitude deeper habitats have the longest species durations. For living populations an inverse relationship between density and diversity suggests scarcity of food is not sufficient to decrease diversity through extinction. For shallower-dwelling species, variability of solar energy can explain the latitudinal gradient. For deep-sea species, energy transfer from the surface, along with environmental stability over vast expanses, are plausible explanations for high diversity.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45118182","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}
The research that Martin A. Buzas has published over the past more than 40 years has influenced us greatly. That research has many strands that cannot be dealt with in this short review. However, the theme of micro- to macroscale foraminiferal distributions is interwoven throughout Buzas's research career. Distributions are something that Buzas is very fond of. He was trained in statistics as well as foraminifera and so it was inevitable that he would combine his knowledge of statistical distributions with foraminiferal distributions at several different scales. He has studied the distribution of foraminifera at microscales, horizontally within a 10 cm2 area of the sea floor or vertically, cm by cm within a 20 cm core. He has also worked at the mesoscale, quantifying, through the pioneering use of the General Linear Model, the relationship of foraminiferal distributions and environmental variables in space and time. This research led to the hypothesis of pulsating patches. He has worked at the macroscale with S. J. Culver, defining the distribution of benthic foraminiferal provinces, showing that all foraminiferal distributions, particularly around the coasts of North and Central America, belong to the same statistical distribution. Their work has documented the assembly and disassembly of communities and the latitudinal patterns of deep-sea benthic foraminiferal diversity in the Atlantic basin. Most recently, with his coauthor, mathematical statistician L. C. Hayek, Buzas has delved deep into the intricacies of species diversity and solved a 50 year-old supposedly intractable problem of mathematically relating species richness with species evenness. This work led to the introduction of new approaches to understanding community structure and recognizing boundaries between adjacent communities (SHE analysis). Many of us work long hours and publish many papers over our careers but few of us truly influence the fundamentals of our science. Marty Buzas is one micropaleontologist whose work will be of lasting significance.
Martin A. Buzas在过去40多年里发表的研究对我们影响很大。这项研究有很多方面，无法在这篇简短的综述中处理。然而，微观到宏观尺度有孔虫分布的主题贯穿了布扎斯的研究生涯。发行版是Buzas非常喜欢的东西。他受过统计学和有孔虫方面的训练，所以他不可避免地要把他的统计分布知识和有孔虫在几个不同尺度上的分布结合起来。他在微观尺度上研究了有孔虫的分布，水平分布在10平方厘米的海底区域内，垂直分布在20厘米的岩心内。他还从事中尺度研究，通过开创性地使用一般线性模型，量化有孔虫分布与空间和时间环境变量的关系。这项研究提出了脉动斑块假说。他在宏观尺度上与S. J. Culver一起工作，定义了底栖有孔虫省的分布，表明所有有孔虫分布，特别是在北美和中美洲海岸周围，属于相同的统计分布。他们的工作记录了大西洋盆地深海底栖有孔虫多样性的群落组合和分解以及纬度模式。最近，布扎斯与数理统计学家哈耶克(L. C. Hayek)合作，深入研究了物种多样性的复杂性，并解决了一个50年来一直被认为难以解决的问题，即物种丰富度与物种均匀度之间的数学关系。这项工作引入了新的方法来理解社区结构和识别相邻社区之间的边界(SHE分析)。我们中的许多人在我们的职业生涯中工作很长时间，发表了很多论文，但我们中很少有人真正影响我们科学的基础。马蒂·布扎斯是一位微生物古生物学家，他的工作将具有持久的意义。
{"title":"Micro- to Macro-Scale Foraminiferal Distributions: The Contributions of Martin A. Buzas*","authors":"S. Culver","doi":"10.2113/gsjfr.53.3.187","DOIUrl":"https://doi.org/10.2113/gsjfr.53.3.187","url":null,"abstract":"\u0000 The research that Martin A. Buzas has published over the past more than 40 years has influenced us greatly. That research has many strands that cannot be dealt with in this short review. However, the theme of micro- to macroscale foraminiferal distributions is interwoven throughout Buzas's research career. Distributions are something that Buzas is very fond of. He was trained in statistics as well as foraminifera and so it was inevitable that he would combine his knowledge of statistical distributions with foraminiferal distributions at several different scales. He has studied the distribution of foraminifera at microscales, horizontally within a 10 cm2 area of the sea floor or vertically, cm by cm within a 20 cm core. He has also worked at the mesoscale, quantifying, through the pioneering use of the General Linear Model, the relationship of foraminiferal distributions and environmental variables in space and time. This research led to the hypothesis of pulsating patches. He has worked at the macroscale with S. J. Culver, defining the distribution of benthic foraminiferal provinces, showing that all foraminiferal distributions, particularly around the coasts of North and Central America, belong to the same statistical distribution. Their work has documented the assembly and disassembly of communities and the latitudinal patterns of deep-sea benthic foraminiferal diversity in the Atlantic basin. Most recently, with his coauthor, mathematical statistician L. C. Hayek, Buzas has delved deep into the intricacies of species diversity and solved a 50 year-old supposedly intractable problem of mathematically relating species richness with species evenness. This work led to the introduction of new approaches to understanding community structure and recognizing boundaries between adjacent communities (SHE analysis). Many of us work long hours and publish many papers over our careers but few of us truly influence the fundamentals of our science. Marty Buzas is one micropaleontologist whose work will be of lasting significance.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43669514","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":"2023 Cushman Foundation for Foraminiferal Research Award and Grant Recipients","authors":"","doi":"10.2113/gsjfr.53.3.266","DOIUrl":"https://doi.org/10.2113/gsjfr.53.3.266","url":null,"abstract":"","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41582708","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}
Most previous accounts summarising the biogeography and species durations of smaller calcareous benthic foraminifera have been based on literature reviews or on a massive North American database that had been taxonomically standardised. In this review we limit consideration to extant and fossil families or genera (from nearshore, open shelf, and deep-sea environments) with modern reviews that have standardised their global morphotaxonomy and where available, are complimented by molecular studies. We confirm previous studies that indicate most shelf species have limited geographic ranges and the majority of deep-water species are widespread and cosmopolitan or nearly so. In our intertidal and inner shelf groups only one species (molecular and morphological), Ammonia veneta, has a cosmopolitan distribution, although four warm-water morphospecies, of Ammonia and Rugobolivinella, have or had distributions that spanned more than one ocean in equatorial latitudes. The majority of both warm- and cool-water species in these groups are regionally or locally-restricted endemics (92% of Bolivinellidae, 100% of Tubulogenerina, 73% of Ammoniidae). The biogeographic distribution of the two rarer, warm-water groups (Bolivinellidae, Tubulogenerina) changed dramatically through the Cenozoic with the Paleocene–Eocene North American–European distribution of Bolivinellidae switching to purely Indo-Pacific by the Pliocene–Quaternary. In our shelf–upper bathyal groups (Notorotaliiidae, Plectofrondiculariidae), two genera have been restricted to the Southern Hemisphere since their Eocene originations with their greatest diversity throughout in New Zealand and Australia, respectively. The dominantly cold-water notorotaliid genus Buccella has a biogeographic distribution largely restricted to the Arctic Ocean and both coasts of North and South America. Most notorotaliid species are locally or regionally endemic (100% of Notorotalia, Parrellina, Porosorotalia, 75% of Buccella). At least 50–60% of species in five extinct mid-bathyal–abyssal families are cosmopolitan and have been throughout the Cenozoic since their originations. The majority of these deep-sea species with more-restricted distributions are rare, and many could possibly be more widespread with further extensive study. This review found that the shortest mean species durations (4–5 myrs) occur in two groups of rather rare, tropical–subtropical inner-shelf foraminifera with many locally endemic species. In cooler and progressively deeper water environments the mean species durations increase to 7–11 myrs for temperate shelf–bathyal taxa (Notorotaliidae), 20 myrs for an extinct mid-shelf to bathyal family (Plectofrondiculariidae) and 41–50 myrs for five extinct mid-bathyal–abyssal families (Chrysalogoniidae, Ellipsoidinidae, Glandulonodosariidae, Pleurostomellidae, Stilostomellidae). One species in each of four of these deep-water families had a species duration of 150–120 myrs.
{"title":"Biogeography and Species Durations of Selected Cenozoic Shallow and Deep-Water Smaller Calcareous Benthic Foraminifera – A Review","authors":"B. Hayward, M. Holzmann","doi":"10.2113/gsjfr.53.3.192","DOIUrl":"https://doi.org/10.2113/gsjfr.53.3.192","url":null,"abstract":"\u0000 Most previous accounts summarising the biogeography and species durations of smaller calcareous benthic foraminifera have been based on literature reviews or on a massive North American database that had been taxonomically standardised. In this review we limit consideration to extant and fossil families or genera (from nearshore, open shelf, and deep-sea environments) with modern reviews that have standardised their global morphotaxonomy and where available, are complimented by molecular studies.\u0000 We confirm previous studies that indicate most shelf species have limited geographic ranges and the majority of deep-water species are widespread and cosmopolitan or nearly so. In our intertidal and inner shelf groups only one species (molecular and morphological), Ammonia veneta, has a cosmopolitan distribution, although four warm-water morphospecies, of Ammonia and Rugobolivinella, have or had distributions that spanned more than one ocean in equatorial latitudes. The majority of both warm- and cool-water species in these groups are regionally or locally-restricted endemics (92% of Bolivinellidae, 100% of Tubulogenerina, 73% of Ammoniidae). The biogeographic distribution of the two rarer, warm-water groups (Bolivinellidae, Tubulogenerina) changed dramatically through the Cenozoic with the Paleocene–Eocene North American–European distribution of Bolivinellidae switching to purely Indo-Pacific by the Pliocene–Quaternary.\u0000 In our shelf–upper bathyal groups (Notorotaliiidae, Plectofrondiculariidae), two genera have been restricted to the Southern Hemisphere since their Eocene originations with their greatest diversity throughout in New Zealand and Australia, respectively. The dominantly cold-water notorotaliid genus Buccella has a biogeographic distribution largely restricted to the Arctic Ocean and both coasts of North and South America. Most notorotaliid species are locally or regionally endemic (100% of Notorotalia, Parrellina, Porosorotalia, 75% of Buccella). At least 50–60% of species in five extinct mid-bathyal–abyssal families are cosmopolitan and have been throughout the Cenozoic since their originations. The majority of these deep-sea species with more-restricted distributions are rare, and many could possibly be more widespread with further extensive study.\u0000 This review found that the shortest mean species durations (4–5 myrs) occur in two groups of rather rare, tropical–subtropical inner-shelf foraminifera with many locally endemic species. In cooler and progressively deeper water environments the mean species durations increase to 7–11 myrs for temperate shelf–bathyal taxa (Notorotaliidae), 20 myrs for an extinct mid-shelf to bathyal family (Plectofrondiculariidae) and 41–50 myrs for five extinct mid-bathyal–abyssal families (Chrysalogoniidae, Ellipsoidinidae, Glandulonodosariidae, Pleurostomellidae, Stilostomellidae). One species in each of four of these deep-water families had a species duration of 150–120 myrs.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48016037","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}
Benthic foraminifera were collected from reef coral, seagrass and mangrove sediments of Almirante Bay, Caribbean Panama, to associate species and assemblages with habitats and environmental conditions related to degraded water quality. The three habitats occur in different adjacent areas within an embayed, patch-reef setting. We analyzed the relative abundance, diversity and community structure of benthic foraminiferal species > 63 µm in 17 sediment samples from < 2 m mean water depth. Results from hierarchical cluster analysis, analysis of similarity, similarity percentages, non-metric multidimensional scaling and Fisher's alpha diversity were compared from seagrass, mangrove and coral habitats and also between two areas with contrasting water quality as previously defined by hydrography and general water quality. Among the three neighboring habitats, assemblages are fairly similar but differ in species proportions. Overall, Ammonia parkinsoniana, indicative of relatively low and variable salinities, is a dominant taxon. Foraminiferal assemblages from mangroves had the lowest mean diversity, a common trend under reduced salinity conditions, and diversity appears to be regionally controlled by freshwater input. Planorbulina acervalis was dominant in seagrass beds. Low-diversity, stress-tolerant foraminiferal assemblages are present in samples from all three habitats, reflecting the bay's highly variable patch-reef structure, freshwater input, and possible hypoxia. Diversity is generally lower near the mainland than in the eastern bay off the island of Isla Colón. Environmental associations of the benthic foraminifera of Almirante Bay are baseline ecologic data for comparisons to coastal habitats formed before human occupation and have the potential to be used in the sedimentary record to assess the impact of anthropogenic disturbance.
{"title":"Distinguishing Coastal Habitats of Caribbean Panama with Benthic Foraminifera","authors":"M. Gudnitz, L. Collins","doi":"10.2113/gsjfr.53.3.243","DOIUrl":"https://doi.org/10.2113/gsjfr.53.3.243","url":null,"abstract":"\u0000 Benthic foraminifera were collected from reef coral, seagrass and mangrove sediments of Almirante Bay, Caribbean Panama, to associate species and assemblages with habitats and environmental conditions related to degraded water quality. The three habitats occur in different adjacent areas within an embayed, patch-reef setting. We analyzed the relative abundance, diversity and community structure of benthic foraminiferal species > 63 µm in 17 sediment samples from < 2 m mean water depth. Results from hierarchical cluster analysis, analysis of similarity, similarity percentages, non-metric multidimensional scaling and Fisher's alpha diversity were compared from seagrass, mangrove and coral habitats and also between two areas with contrasting water quality as previously defined by hydrography and general water quality.\u0000 Among the three neighboring habitats, assemblages are fairly similar but differ in species proportions. Overall, Ammonia parkinsoniana, indicative of relatively low and variable salinities, is a dominant taxon. Foraminiferal assemblages from mangroves had the lowest mean diversity, a common trend under reduced salinity conditions, and diversity appears to be regionally controlled by freshwater input. Planorbulina acervalis was dominant in seagrass beds. Low-diversity, stress-tolerant foraminiferal assemblages are present in samples from all three habitats, reflecting the bay's highly variable patch-reef structure, freshwater input, and possible hypoxia. Diversity is generally lower near the mainland than in the eastern bay off the island of Isla Colón. Environmental associations of the benthic foraminifera of Almirante Bay are baseline ecologic data for comparisons to coastal habitats formed before human occupation and have the potential to be used in the sedimentary record to assess the impact of anthropogenic disturbance.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49160634","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}
A planktic foraminiferal mass extinction, coeval with the major carbon cycle perturbation of Oceanic Anoxic Event (OAE) 1b, occurred at the Aptian−Albian boundary interval (AABI). However, the scarcity of high-resolution records across the AABI hampers an assessment of the impacts of OAE 1b on deep-water benthic foraminiferal assemblages. Here we present high-resolution benthic foraminiferal census counts at Deep Sea Drilling Project (DSDP) Site 511 (southern South Atlantic Ocean) and Ocean Drilling Program (ODP) Site 1049 (western subtropical North Atlantic Ocean) over the AABI. Our records at these bathyal sites provide conclusive evidence that there was no benthic foraminiferal extinction at the Aptian−Albian boundary, although marked reorganizations of relative abundances occurred. During the latest Aptian, cyclic increases in the abundance of infaunal species at both sites point to repeated pulses of reduced bottom water oxygenation and increased organic carbon flux to the ocean floor. Additionally, agglutinated and weakly calcified benthic foraminiferal species were relatively abundant during the latest Aptian, suggesting deep-water carbonate ion depletion in the Atlantic Ocean, although we did not identify signs of carbonate dissolution at these relatively shallow sites. At Site 511, abundances of infaunal foraminifera increased in tandem with the negative carbonate carbon isotope (δ13Ccarb) excursion of the Kilian sub-event within OAE 1b, suggesting decreased bottom water ventilation and increased organic carbon flux to the ocean floor during the sub-event. Bottom water ventilation and carbonate ion saturation improved during the earliest Albian in the Atlantic Ocean, followed by high-amplitude oscillations, as suggested by abundance trends of heavily calcified epifaunal foraminifera at Sites 511 and 1049.
{"title":"Benthic Foraminiferal Response to the Aptian−Albian Carbon Cycle Perturbation in the Atlantic Ocean","authors":"K. Kochhann, B. Huber, A. Holbourn, W. Kuhnt","doi":"10.2113/gsjfr.53.3.214","DOIUrl":"https://doi.org/10.2113/gsjfr.53.3.214","url":null,"abstract":"\u0000 A planktic foraminiferal mass extinction, coeval with the major carbon cycle perturbation of Oceanic Anoxic Event (OAE) 1b, occurred at the Aptian−Albian boundary interval (AABI). However, the scarcity of high-resolution records across the AABI hampers an assessment of the impacts of OAE 1b on deep-water benthic foraminiferal assemblages. Here we present high-resolution benthic foraminiferal census counts at Deep Sea Drilling Project (DSDP) Site 511 (southern South Atlantic Ocean) and Ocean Drilling Program (ODP) Site 1049 (western subtropical North Atlantic Ocean) over the AABI. Our records at these bathyal sites provide conclusive evidence that there was no benthic foraminiferal extinction at the Aptian−Albian boundary, although marked reorganizations of relative abundances occurred. During the latest Aptian, cyclic increases in the abundance of infaunal species at both sites point to repeated pulses of reduced bottom water oxygenation and increased organic carbon flux to the ocean floor. Additionally, agglutinated and weakly calcified benthic foraminiferal species were relatively abundant during the latest Aptian, suggesting deep-water carbonate ion depletion in the Atlantic Ocean, although we did not identify signs of carbonate dissolution at these relatively shallow sites. At Site 511, abundances of infaunal foraminifera increased in tandem with the negative carbonate carbon isotope (δ13Ccarb) excursion of the Kilian sub-event within OAE 1b, suggesting decreased bottom water ventilation and increased organic carbon flux to the ocean floor during the sub-event. Bottom water ventilation and carbonate ion saturation improved during the earliest Albian in the Atlantic Ocean, followed by high-amplitude oscillations, as suggested by abundance trends of heavily calcified epifaunal foraminifera at Sites 511 and 1049.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47796246","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}
Two cores were studied from Liverpool Bay (∼40 m water depth). The lowest 80 cm of ISLF13 (290 cm long) comprised clay, gypsum and pyritised foraminifera (Surface Layer 2 Member, gypsiferous lithofacies GLF) from a tidal flat dominated by Cribroelphidium excavatum. Perturbation Detection Analysis (PDA) found two ISLF13 GLF abundance biozones (ABs) with assemblages in stasis. ISLF16 (80 cm long) and between 30–202 cm in ISLF13 were open marine, sandy with gastropods and bivalves (Surface Layer 1 Member, shelly sand lithofacies SSLF). Assemblages in the SSLF sections differed, despite their proximity. That in ISLF13 comprised dominant C. excavatum with lesser Ammonia batava, Asterigerinata mamilla, Cibicides refulgens and Bulimina elongata. PDA identified two ISLF13 SSLF ABs, both in growth stages. The ISLF16 assemblage was co-dominated by C. excavatum, A. mamilla and A. batava from a single AB in stasis. This difference might reflect sorting. Asterigerinata murraynhaynesi n. sp. is described.
{"title":"The Later Holocene Foraminifera of Liverpool Bay (Bae Lerpwl), British Isles: Morphospecies and Community Level Patterns","authors":"B. Wilson, L. Hayek","doi":"10.2113/gsjfr.53.3.226","DOIUrl":"https://doi.org/10.2113/gsjfr.53.3.226","url":null,"abstract":"\u0000 Two cores were studied from Liverpool Bay (∼40 m water depth). The lowest 80 cm of ISLF13 (290 cm long) comprised clay, gypsum and pyritised foraminifera (Surface Layer 2 Member, gypsiferous lithofacies GLF) from a tidal flat dominated by Cribroelphidium excavatum. Perturbation Detection Analysis (PDA) found two ISLF13 GLF abundance biozones (ABs) with assemblages in stasis. ISLF16 (80 cm long) and between 30–202 cm in ISLF13 were open marine, sandy with gastropods and bivalves (Surface Layer 1 Member, shelly sand lithofacies SSLF). Assemblages in the SSLF sections differed, despite their proximity. That in ISLF13 comprised dominant C. excavatum with lesser Ammonia batava, Asterigerinata mamilla, Cibicides refulgens and Bulimina elongata. PDA identified two ISLF13 SSLF ABs, both in growth stages. The ISLF16 assemblage was co-dominated by C. excavatum, A. mamilla and A. batava from a single AB in stasis. This difference might reflect sorting. Asterigerinata murraynhaynesi n. sp. is described.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41776419","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}
M. Galochkina, M. Makarova, K. Miller, J. Browning, Ronan S. Keating, J. Wright
We reconstruct the subtropical North Atlantic water column structure during the Miocene Climate Optimum warming (MCO; 17–14.8 Ma) and the Middle Miocene Climate Transition cooling (MMCT; 14.8–12.8 Ma) by analyzing δ18O and δ13C in four species of foraminifera (surface dwellers Dentoglobigerina altispira and Trilobatus quadrilobatus, thermocline dweller Dentoglobigerina venezuelana, and benthic Planulina wuellerstorfi) from Site 558 (37.8°N). At the end of the MCO, δ18O of surface and thermocline dwellers increased by >1‰, suggesting at least 2°C cooling in the upper ocean as ice growth increased global δ18Osw by ∼0.5‰. The difference in δ18O values between thermocline and surface-dwelling species increased during the MMCT, coinciding with the development of a largely permanent East Antarctic Ice Sheet, and persisted into the Late Miocene. We interpret this increase in vertical δ18O gradient as a strengthening of the thermocline due to intensification of subtropical gyre circulation in response to the MMCT cooling.
{"title":"Multispecies Planktonic and Benthic Foraminiferal Stable Isotopes from North Atlantic Subtropical Site 558: Thermocline Intensification During the Mid-Miocene Climate Transition","authors":"M. Galochkina, M. Makarova, K. Miller, J. Browning, Ronan S. Keating, J. Wright","doi":"10.2113/gsjfr.53.2.143","DOIUrl":"https://doi.org/10.2113/gsjfr.53.2.143","url":null,"abstract":"\u0000 We reconstruct the subtropical North Atlantic water column structure during the Miocene Climate Optimum warming (MCO; 17–14.8 Ma) and the Middle Miocene Climate Transition cooling (MMCT; 14.8–12.8 Ma) by analyzing δ18O and δ13C in four species of foraminifera (surface dwellers Dentoglobigerina altispira and Trilobatus quadrilobatus, thermocline dweller Dentoglobigerina venezuelana, and benthic Planulina wuellerstorfi) from Site 558 (37.8°N). At the end of the MCO, δ18O of surface and thermocline dwellers increased by >1‰, suggesting at least 2°C cooling in the upper ocean as ice growth increased global δ18Osw by ∼0.5‰. The difference in δ18O values between thermocline and surface-dwelling species increased during the MMCT, coinciding with the development of a largely permanent East Antarctic Ice Sheet, and persisted into the Late Miocene. We interpret this increase in vertical δ18O gradient as a strengthening of the thermocline due to intensification of subtropical gyre circulation in response to the MMCT cooling.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45131411","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}
S. Bhadra, R. Saraswat, Gavendra Kumar, T. Suokhrie
The first and last occurrence datums of species are often used as biostratigraphic markers to establish chronology beyond the range of radiocarbon dating. One such datum, the last occurrence of Globigerinoides ruber (pink) from the Indo-Pacific region, has been extensively used as a biostratigraphic marker. However, the first occurrence of G. ruber (pink) in the Indian Ocean and the possible causes thereof are debated. We report the first and last occurrence datums of G. ruber (pink) from the northern Indian Ocean and explore the possible reasons for its first and last occurrence. The first occurrence of G. ruber (pink) in the Bay of Bengal is 399 ka. The last occurrence datums are 128 ka and 123 ka in the Bay of Bengal and Arabian Sea, respectively. The occurrence of G. ruber (pink) in the Indian Ocean is attributed to its invasion through the warmer southeast Atlantic Ocean via the Agulhas Return Current. Based on the synchronous occurrence during Marine Isotopic Stage 11, we propose that the first occurrence of G. ruber (pink) can be used as an additional marker throughout the northern Indian Ocean.
{"title":"Revisiting the Biostratigraphic Range and Possible Cause of the First and Last Occurrence of Globigerinoides Ruber (Pink) in the Northern Indian Ocean","authors":"S. Bhadra, R. Saraswat, Gavendra Kumar, T. Suokhrie","doi":"10.2113/gsjfr.53.2.120","DOIUrl":"https://doi.org/10.2113/gsjfr.53.2.120","url":null,"abstract":"\u0000 The first and last occurrence datums of species are often used as biostratigraphic markers to establish chronology beyond the range of radiocarbon dating. One such datum, the last occurrence of Globigerinoides ruber (pink) from the Indo-Pacific region, has been extensively used as a biostratigraphic marker. However, the first occurrence of G. ruber (pink) in the Indian Ocean and the possible causes thereof are debated. We report the first and last occurrence datums of G. ruber (pink) from the northern Indian Ocean and explore the possible reasons for its first and last occurrence. The first occurrence of G. ruber (pink) in the Bay of Bengal is 399 ka. The last occurrence datums are 128 ka and 123 ka in the Bay of Bengal and Arabian Sea, respectively. The occurrence of G. ruber (pink) in the Indian Ocean is attributed to its invasion through the warmer southeast Atlantic Ocean via the Agulhas Return Current. Based on the synchronous occurrence during Marine Isotopic Stage 11, we propose that the first occurrence of G. ruber (pink) can be used as an additional marker throughout the northern Indian Ocean.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45220610","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}
Favocassidulina tuberculata, a new benthic foraminiferal species from Integrated Ocean Drilling Program Site U1391 drilled on the southwest Portuguese continental slope, is described. This new species has a slit-shaped apertural opening oblique to the test periphery instead of paralleling the periphery as the type species Favocassidulina favus (Brady) does. And more notably, this species possesses a test surface ornamented with tubercles, quite different from the coarse honeycomb wall structure of F. favus and the finely irregular cancellate surface ornamentation of other Favocassidulina species. This paper for the first time reports the presence of the genus Favocassidulina in the Atlantic Ocean.
{"title":"Favocassidulina Tuberculata N. SP., A New Benthic Foraminifer from the Portuguese Continental Slope","authors":"Qimei Guo","doi":"10.2113/gsjfr.53.2.131","DOIUrl":"https://doi.org/10.2113/gsjfr.53.2.131","url":null,"abstract":"\u0000 Favocassidulina tuberculata, a new benthic foraminiferal species from Integrated Ocean Drilling Program Site U1391 drilled on the southwest Portuguese continental slope, is described. This new species has a slit-shaped apertural opening oblique to the test periphery instead of paralleling the periphery as the type species Favocassidulina favus (Brady) does. And more notably, this species possesses a test surface ornamented with tubercles, quite different from the coarse honeycomb wall structure of F. favus and the finely irregular cancellate surface ornamentation of other Favocassidulina species. This paper for the first time reports the presence of the genus Favocassidulina in the Atlantic Ocean.","PeriodicalId":54832,"journal":{"name":"Journal of Foraminiferal Research","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48793237","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}
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