Elucidating how environmental change can facilitate the differentiation of evolutionary lineages and the establishment of new species is a critical issue for understanding both the history of life and modern biota. Notably, speciation events are known to be the main drivers of bio - diversification; thus, generating well-constrained phylogenetic hypotheses to investigate speciation processes and facilitators can provide key data on links between biogeography, speciation, and diversification. During the Great Ordovician Biodiversification Event (GOBE), articulate brachiopods were a key group on the rise. By the Middle to Late Ordovician, the brachiopod order Atrypida was no exception. The atrypids diversified greatly and established evolutionary novelties such as helical and calcite-supported lophophores. The Ordovician epi - continental seas in eastern Laurentia provided an excellent environment for reproductive isolation and speciation, with sea-level fluctuations, ideal climate conditions, and active tectonic settings. However, speciation patterns and drivers within two widely-distributed atrypid sub - families, Anazyginae ( Anazyga spp. and Zygospira spp. ) and Catazyginae ( Catazyga spp. ) , remain poorly known. In this project, we seek to develop a robust phylogenetic framework for these clades and use that framework to evaluate speciation processes and facilitators during the Late Ordovician. Morphological data will be collected from published
{"title":"Developing a phylogenetic framework for tiny Ordovician brachiopods (Atrypida: Anazyginae and Catazyginae) from the eastern United States","authors":"Mariana Vilela-Andrade, A. Stigall","doi":"10.3176/earth.2023.73","DOIUrl":"https://doi.org/10.3176/earth.2023.73","url":null,"abstract":"Elucidating how environmental change can facilitate the differentiation of evolutionary lineages and the establishment of new species is a critical issue for understanding both the history of life and modern biota. Notably, speciation events are known to be the main drivers of bio - diversification; thus, generating well-constrained phylogenetic hypotheses to investigate speciation processes and facilitators can provide key data on links between biogeography, speciation, and diversification. During the Great Ordovician Biodiversification Event (GOBE), articulate brachiopods were a key group on the rise. By the Middle to Late Ordovician, the brachiopod order Atrypida was no exception. The atrypids diversified greatly and established evolutionary novelties such as helical and calcite-supported lophophores. The Ordovician epi - continental seas in eastern Laurentia provided an excellent environment for reproductive isolation and speciation, with sea-level fluctuations, ideal climate conditions, and active tectonic settings. However, speciation patterns and drivers within two widely-distributed atrypid sub - families, Anazyginae ( Anazyga spp. and Zygospira spp. ) and Catazyginae ( Catazyga spp. ) , remain poorly known. In this project, we seek to develop a robust phylogenetic framework for these clades and use that framework to evaluate speciation processes and facilitators during the Late Ordovician. Morphological data will be collected from published","PeriodicalId":50498,"journal":{"name":"Estonian Journal of Earth Sciences","volume":"84 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77535170","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}
Q. Li, L. Na, S. Yu, O. Lehnert, A. Munneck, L. Yue
{"title":"Late Ordovician beachrock as a far-field indicator for glacial meltwater pulse","authors":"Q. Li, L. Na, S. Yu, O. Lehnert, A. Munneck, L. Yue","doi":"10.3176/earth.2023.13","DOIUrl":"https://doi.org/10.3176/earth.2023.13","url":null,"abstract":"","PeriodicalId":50498,"journal":{"name":"Estonian Journal of Earth Sciences","volume":"5 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87900321","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. Nohejlová, C. Dupichaud, B. Lefebvre, E. Nardin, F. Saleh
{"title":"Echinoderm Lagerstätten from high-latitude Gondwana – filling the gap in the Ordovician diversification of the phylum","authors":"M. Nohejlová, C. Dupichaud, B. Lefebvre, E. Nardin, F. Saleh","doi":"10.3176/earth.2023.45","DOIUrl":"https://doi.org/10.3176/earth.2023.45","url":null,"abstract":"","PeriodicalId":50498,"journal":{"name":"Estonian Journal of Earth Sciences","volume":"11 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87690059","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 Borenshult-1 core, drilled in the vicinity of Motala, east of Lake Vättern in south central Sweden, comprises a well-dated and nearly complete succession of marine marly carbonates deposited relatively close to land. The 34 core samples analyzed for palynology encompass the upper part of the Darriwilian (Furudal Limestone), the entire Sandbian (Dalby Limestone, the Kinnekulle K-bentonite and the lower Skagen Limestone) and the lower part of the Katian (Skagen Limestone). The age of this interval is well-constrained to the late Darriwilian (Stage slice Dw3)– early Katian (Stage slice Ka1 ) , based on conodonts and 206Pb/238U dating of volcanic ash deposits. The samples yielded predominantly marine organic-walled phytoplankton, mainly acritarchs, with subordinate chitinozoans, scolecodonts and fragments of graptolites. Sparse terrestrial palynomorphs, represented by cryptospores and trilete spores, were also found in 23 of the samples. A total of 154 acritarch species corresponding to 53 genera were identified, as well as low percentages of abnormal forms ( teratological forms) of acritarch species at some levels. The strati graphic distribution of genera and species allowed for three palynological assemblages to be distinguished: Assemblage A of a late Darriwilian age, Assemblage B of a Sandbian age ( further subdivided into sub-assemblages B1 and B2 ) , and Assemblage C dated as Katian.
Borenshult-1岩心是在瑞典中南部Vättern湖以东的Motala附近钻探的，包含了一个年代久远、几乎完整的海相碳酸盐岩序列，它们沉积在相对靠近陆地的地方。孢粉学分析的34个岩心样品包括达里威廉(Furudal灰岩)上部、整个沙边(Dalby灰岩、Kinnekulle k -膨润土和下斯卡根灰岩)和卡田(Skagen灰岩)下部。根据牙形刺和火山灰沉积物的206Pb/238U定年，该层序的年龄很好地限定在达里威廉晚期(Dw3阶段)-卡天早期(Ka1阶段)。样品中主要有海洋有机壁浮游植物，主要是水螅类，次要有几丁质动物、棘刺类和笔石碎片。在23份样品中还发现了稀疏的陆生孢子，以隐孢子和三孢子为代表。共鉴定出53属154种，在某些层次上有较低的畸形形态(畸形形态)。属和种的地层分布可区分出3个孢粉组合:晚达里威廉时代的组合A、沙边时代的组合B(进一步细分为亚组合B1和B2)和卡天时代的组合C。
{"title":"Middle–Late Ordovician organic- walled phytoplankton from Sweden: diversity and early radiation","authors":"C. V. Rubinstein, V. Vajda","doi":"10.3176/earth.2023.42","DOIUrl":"https://doi.org/10.3176/earth.2023.42","url":null,"abstract":"The Borenshult-1 core, drilled in the vicinity of Motala, east of Lake Vättern in south central Sweden, comprises a well-dated and nearly complete succession of marine marly carbonates deposited relatively close to land. The 34 core samples analyzed for palynology encompass the upper part of the Darriwilian (Furudal Limestone), the entire Sandbian (Dalby Limestone, the Kinnekulle K-bentonite and the lower Skagen Limestone) and the lower part of the Katian (Skagen Limestone). The age of this interval is well-constrained to the late Darriwilian (Stage slice Dw3)– early Katian (Stage slice Ka1 ) , based on conodonts and 206Pb/238U dating of volcanic ash deposits. The samples yielded predominantly marine organic-walled phytoplankton, mainly acritarchs, with subordinate chitinozoans, scolecodonts and fragments of graptolites. Sparse terrestrial palynomorphs, represented by cryptospores and trilete spores, were also found in 23 of the samples. A total of 154 acritarch species corresponding to 53 genera were identified, as well as low percentages of abnormal forms ( teratological forms) of acritarch species at some levels. The strati graphic distribution of genera and species allowed for three palynological assemblages to be distinguished: Assemblage A of a late Darriwilian age, Assemblage B of a Sandbian age ( further subdivided into sub-assemblages B1 and B2 ) , and Assemblage C dated as Katian.","PeriodicalId":50498,"journal":{"name":"Estonian Journal of Earth Sciences","volume":"67 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90830188","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":"On future directions of Ordovician chitinozoan research","authors":"Y. Liang, O. Hints, J. Nõlvak, P. Tang","doi":"10.3176/earth.2023.34","DOIUrl":"https://doi.org/10.3176/earth.2023.34","url":null,"abstract":"","PeriodicalId":50498,"journal":{"name":"Estonian Journal of Earth Sciences","volume":"51 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79327679","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 western Iberian Chain of NE Spain represents a lateral prolongation of the West AsturianLeonese Zone. As other proximal sectors fringing NW Gondwana, the chain comprises a con formable and continuous Furongian‒Tremadocian transition, comprising a thick (3600‒4500 m) Lower Ordovician sedimentary succession, exclusively composed of siliciclastic strata and deposited in mid-latitude (temperate) waters. Although the shelly fossil record is not abun dant, some key trilobites and brachiopods allow the identification of distinct biogeographic links with the Argentinian margin of West Gondwana, Oaxaca (Mexico), and the neighbouring Montagne Noire (France), with which a common biostratigraphic biozonation can be en vis aged. Two phosphoritic interbeds rich in linguliformean brachiopods punctuate the Valconchán and Borrachón formations, and represent event beds related to condensation processes and sedimentation of explosive ignimbritic tuffs, respectively.
{"title":"Advances in the Lower Ordovician of the western Iberian Chain, NE Spain","authors":"J. Álvaro, Blanca Martínez-Benítez","doi":"10.3176/earth.2023.15","DOIUrl":"https://doi.org/10.3176/earth.2023.15","url":null,"abstract":"The western Iberian Chain of NE Spain represents a lateral prolongation of the West AsturianLeonese Zone. As other proximal sectors fringing NW Gondwana, the chain comprises a con formable and continuous Furongian‒Tremadocian transition, comprising a thick (3600‒4500 m) Lower Ordovician sedimentary succession, exclusively composed of siliciclastic strata and deposited in mid-latitude (temperate) waters. Although the shelly fossil record is not abun dant, some key trilobites and brachiopods allow the identification of distinct biogeographic links with the Argentinian margin of West Gondwana, Oaxaca (Mexico), and the neighbouring Montagne Noire (France), with which a common biostratigraphic biozonation can be en vis aged. Two phosphoritic interbeds rich in linguliformean brachiopods punctuate the Valconchán and Borrachón formations, and represent event beds related to condensation processes and sedimentation of explosive ignimbritic tuffs, respectively.","PeriodicalId":50498,"journal":{"name":"Estonian Journal of Earth Sciences","volume":"70 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79969883","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}
L. Holmer, L. Popov, M. G. Pour, Y. Liang, Z. Zhang
Received 21 March 2023 Accepted 30 March 2023 Available online 8 June 2023
2023年3月21日收稿，2023年3月30日录用，2023年6月8日在线发表
{"title":"Siphonotretoid brachiopods – a thorny problem","authors":"L. Holmer, L. Popov, M. G. Pour, Y. Liang, Z. Zhang","doi":"10.3176/earth.2023.02","DOIUrl":"https://doi.org/10.3176/earth.2023.02","url":null,"abstract":"Received 21 March 2023 Accepted 30 March 2023 Available online 8 June 2023","PeriodicalId":50498,"journal":{"name":"Estonian Journal of Earth Sciences","volume":"46 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91341366","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":"A remarkable new halichondrid demosponge, Ptilospongia hemisphaeroidalis, from the latest Ordovician Beigong Biota, South China","authors":"L. Li, J. Reitner","doi":"10.3176/earth.2023.76","DOIUrl":"https://doi.org/10.3176/earth.2023.76","url":null,"abstract":"","PeriodicalId":50498,"journal":{"name":"Estonian Journal of Earth Sciences","volume":"43 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74010254","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}
Black gas shales are major parts of many foreland-basin sequences and comprise important components of unconformity-bound tectophase cycles, which reflect sedimentary/stratigraphic, flexural responses to deformational loading and relaxation in an orogen. Using as examples Upper Ordovician black gas shales, deposited during the Taconian orogeny in the Appalachian Basin of the eastern United States, black-shale origins and their importance in understanding the tectonic framework are discussed. Foreland-basin black shales are clearly the product of distinctive tectonic frameworks and histories, and aside from economic value, may provide important controls on the timing and location of tectonic events.
{"title":"Tectonic, foreland-basin origins of Upper Ordovician black gas shales in the Appalachian Basin of eastern United States","authors":"F. Ettensohn, G. Martins","doi":"10.3176/earth.2023.64","DOIUrl":"https://doi.org/10.3176/earth.2023.64","url":null,"abstract":"Black gas shales are major parts of many foreland-basin sequences and comprise important components of unconformity-bound tectophase cycles, which reflect sedimentary/stratigraphic, flexural responses to deformational loading and relaxation in an orogen. Using as examples Upper Ordovician black gas shales, deposited during the Taconian orogeny in the Appalachian Basin of the eastern United States, black-shale origins and their importance in understanding the tectonic framework are discussed. Foreland-basin black shales are clearly the product of distinctive tectonic frameworks and histories, and aside from economic value, may provide important controls on the timing and location of tectonic events.","PeriodicalId":50498,"journal":{"name":"Estonian Journal of Earth Sciences","volume":"33 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90595369","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":"Variations in wind velocity components and average air flow properties at Estonian coastal stations in 1966–2021; Sõrve Peninsula case study","authors":"Ü Suursaar","doi":"10.3176/earth.2023.85","DOIUrl":"https://doi.org/10.3176/earth.2023.85","url":null,"abstract":"","PeriodicalId":50498,"journal":{"name":"Estonian Journal of Earth Sciences","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135104314","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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