{"title":"EVENTS IN THE CONODONT HISTORY DURING THE SILURIAN IN ESTONIA","authors":"P. Männik, V. Viira","doi":"10.3176/geol.1993.2.03","DOIUrl":"https://doi.org/10.3176/geol.1993.2.03","url":null,"abstract":"","PeriodicalId":237994,"journal":{"name":"Proceedings of the Estonian Academy of Sciences. Geology","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127795031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
. The position of the Llandevery—Wenlock boundary in the Timan—northern Ural region and Severnaya Zemlya has been under discussion for a long time. Datings based on different groups of fauna seem to be inconsistent; conodonts indicate that in both regions this boundary lies considerably higher in the sequence than considered until now. The conodont datings agree well with correlations based on sea level fluctuations.
{"title":"THE LLANDOVERY-WENLOCK BOUNDARY IN THE RUSSIAN ARCTIC","authors":"P. Männik, A. Antoshkina, Tatyana M. Beznosova","doi":"10.3176/geol.2000.2.03","DOIUrl":"https://doi.org/10.3176/geol.2000.2.03","url":null,"abstract":". The position of the Llandevery—Wenlock boundary in the Timan—northern Ural region and Severnaya Zemlya has been under discussion for a long time. Datings based on different groups of fauna seem to be inconsistent; conodonts indicate that in both regions this boundary lies considerably higher in the sequence than considered until now. The conodont datings agree well with correlations based on sea level fluctuations.","PeriodicalId":237994,"journal":{"name":"Proceedings of the Estonian Academy of Sciences. Geology","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129057419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
It is customary to utilize the Earth's artificial satellites for detecting long-wavelength components of the Earth's gravity field. The tracking data of the GRACE twin-satellites are the basis of t ...
{"title":"Effect of the GRACE satellite mission on gravity field studies in Fennoscandia and the Baltic Sea region","authors":"A. Ellmann","doi":"10.3176/geol.2004.2.01","DOIUrl":"https://doi.org/10.3176/geol.2004.2.01","url":null,"abstract":"It is customary to utilize the Earth's artificial satellites for detecting long-wavelength components of the Earth's gravity field. The tracking data of the GRACE twin-satellites are the basis of t ...","PeriodicalId":237994,"journal":{"name":"Proceedings of the Estonian Academy of Sciences. Geology","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133532164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
. The authors restudied biostratigraphically the stratotypes of the Ilmen Beds and Buregi Beds distinguished by R. Hecker in the Frasnian of the central part of the Main Devonian Field (Lake Ilmen region, Russian Platform). Abundant brachiopod, ostracode, and conodont associations were obtained and one new ostracode species Milanovskya bicristata was described. Both the Ilmen (mainly terrigenous) and Buregi (carbonate) beds correspond to relatively shallow-water facies. Conodont associations permit us to correlate these beds with the Middle-Upper asymmetricus Zone and to recognize two local zones (the Polygnathus pollocki Zone and the P. efimovae Zone). Ostracode, brachiopod, and conodont faunas observed in the Ilmen and Buregi beds resemble the Semilukian ones of the Central Devonian Field. Facial, taphonomical, and some palaeoecological observations allow for the reconstruction of the palaeolandscape succession which was caused by regional sea-level changes.
{"title":"NEW DATA ON CONODONTS, BRACHIOPODS, AND OSTRACODES FROM THE STRATOTYPES OF THE ILMEN AND BUREGI BEDS (FRASNIAN, MAIN DEVONIAN FIELD)","authors":"I. Evdokimova, E. Sokiran, Andrey V. Zhuravlev","doi":"10.3176/geol.1997.4.02","DOIUrl":"https://doi.org/10.3176/geol.1997.4.02","url":null,"abstract":". The authors restudied biostratigraphically the stratotypes of the Ilmen Beds and Buregi Beds distinguished by R. Hecker in the Frasnian of the central part of the Main Devonian Field (Lake Ilmen region, Russian Platform). Abundant brachiopod, ostracode, and conodont associations were obtained and one new ostracode species Milanovskya bicristata was described. Both the Ilmen (mainly terrigenous) and Buregi (carbonate) beds correspond to relatively shallow-water facies. Conodont associations permit us to correlate these beds with the Middle-Upper asymmetricus Zone and to recognize two local zones (the Polygnathus pollocki Zone and the P. efimovae Zone). Ostracode, brachiopod, and conodont faunas observed in the Ilmen and Buregi beds resemble the Semilukian ones of the Central Devonian Field. Facial, taphonomical, and some palaeoecological observations allow for the reconstruction of the palaeolandscape succession which was caused by regional sea-level changes.","PeriodicalId":237994,"journal":{"name":"Proceedings of the Estonian Academy of Sciences. Geology","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130734982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
An overview of 85 sites of Holocene buried organic sediments in Estonia is presented. This number includes 45 sites of pre-Ancylus and Ancylus age, which were buried during the Ancylus transgression, 31 sites of pre-Litorina and Litorina age, buried under Litorina transgression sediments, and 9 sites formed after post-Litorina time and mostly covered by aeolian sand. According to radiocarbon dates, the Ancylus Lake transgression started about 9500 yr BP (10 800 cal BP), and culminated several hundred years later. Around 9000 yr BP (10 100 cal BP) a rather rapid regression followed. Its magnitude reached up to 30 m in the areas of rapid uplift. Pollen spectra of these beds are characterized by a high frequency of Pinus pollen, which seems to be typical of the coastal waterbodies of this age and confuses determination of their Preboreal age. 14 C dates of Litorina buried beds differ considerably. We have evidence that the Litorina transgression started about 7500-7000 yr BP (8300-7800 cal BP) and culminated at different times in different regions. Pollen spectra of Litorina buried organic strata vary considerably between sites; however, their Atlantic age is easily discernible. The simulated isobases of the Ancylus Lake and Litorina Sea shorelines and organic beds showed discrepancy in the surroundings of Parnu and Narva bays.
介绍了爱沙尼亚85个全新世埋藏有机沉积物遗址的概况。其中，前Ancylus和Ancylus时代45个遗址埋于Ancylus海侵时期，前Litorina和Litorina时代31个遗址埋于Litorina海侵沉积物之下，后Litorina时代9个遗址形成于后Litorina时代，主要被风成沙覆盖。根据放射性碳测年，Ancylus湖海侵开始于9500年BP (10800 cal BP)，并在几百年后达到顶峰。在9000年BP (10 100 cal BP)左右，一个相当快速的回归随之而来。在快速隆升地区，其震级可达30 m。这些床的花粉谱以松花粉的高频率为特征，这似乎是该时代沿海水体的典型特征，并混淆了其前寒武纪时代的确定。Litorina埋床的14c年代差异很大。我们有证据表明，Litorina海侵大约开始于7500-7000年BP (8300-7800 cal BP)，在不同的地区在不同的时间达到高潮。Litorina埋藏有机地层的花粉谱在不同地点差异较大;然而，它们的大西洋年龄很容易辨别。在帕尔努湾和纳尔瓦湾周围，模拟的安丘勒斯湖和利托里纳海岸线和有机层等底存在差异。
{"title":"Holocene buried organic sediments in Estonia","authors":"L. Saarse, J. Vassiljev, A. Miidel, E. Niinemets","doi":"10.3176/geol.2006.4.03","DOIUrl":"https://doi.org/10.3176/geol.2006.4.03","url":null,"abstract":"An overview of 85 sites of Holocene buried organic sediments in Estonia is presented. This number includes 45 sites of pre-Ancylus and Ancylus age, which were buried during the Ancylus transgression, 31 sites of pre-Litorina and Litorina age, buried under Litorina transgression sediments, and 9 sites formed after post-Litorina time and mostly covered by aeolian sand. According to radiocarbon dates, the Ancylus Lake transgression started about 9500 yr BP (10 800 cal BP), and culminated several hundred years later. Around 9000 yr BP (10 100 cal BP) a rather rapid regression followed. Its magnitude reached up to 30 m in the areas of rapid uplift. Pollen spectra of these beds are characterized by a high frequency of Pinus pollen, which seems to be typical of the coastal waterbodies of this age and confuses determination of their Preboreal age. 14 C dates of Litorina buried beds differ considerably. We have evidence that the Litorina transgression started about 7500-7000 yr BP (8300-7800 cal BP) and culminated at different times in different regions. Pollen spectra of Litorina buried organic strata vary considerably between sites; however, their Atlantic age is easily discernible. The simulated isobases of the Ancylus Lake and Litorina Sea shorelines and organic beds showed discrepancy in the surroundings of Parnu and Narva bays.","PeriodicalId":237994,"journal":{"name":"Proceedings of the Estonian Academy of Sciences. Geology","volume":"44 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130740069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Different aspects of intraspecific variation in Wenlock tabulate corals are discussed. Intracorallum and intraspecific variation is demonstrated in specimens within the collection from one locality. The diagnostic characters of Halysites senior Klaamann and Catenipora oriens Klaamann and those of Paleofavosites secundus (Klaamann) and Favosites jaaniensis Sokolov overlap and therefore these species are regarded as synonyms. Propora raricellata Sokolov is a possible synonym of P. tubulata (Lonsdale), because the character differentiating these species is variable.
{"title":"Intraspecific variation in Wenlock tabulate corals from Saaremaa (Estonia) and its taxonomic implications","authors":"M. Mõtus","doi":"10.3176/geol.2006.1.02","DOIUrl":"https://doi.org/10.3176/geol.2006.1.02","url":null,"abstract":"Different aspects of intraspecific variation in Wenlock tabulate corals are discussed. Intracorallum and intraspecific variation is demonstrated in specimens within the collection from one locality. The diagnostic characters of Halysites senior Klaamann and Catenipora oriens Klaamann and those of Paleofavosites secundus (Klaamann) and Favosites jaaniensis Sokolov overlap and therefore these species are regarded as synonyms. Propora raricellata Sokolov is a possible synonym of P. tubulata (Lonsdale), because the character differentiating these species is variable.","PeriodicalId":237994,"journal":{"name":"Proceedings of the Estonian Academy of Sciences. Geology","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131930837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"FELDSPARS IN THE TERRIGENOUS SEDIMENTARY ROCKS OF ESTONIA ACCORDING TO X-RAY STRUCTURAL ANALYSIS","authors":"T. Kallaste, E. Pirrus","doi":"10.3176/geol.1994.1.04","DOIUrl":"https://doi.org/10.3176/geol.1994.1.04","url":null,"abstract":"","PeriodicalId":237994,"journal":{"name":"Proceedings of the Estonian Academy of Sciences. Geology","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134562103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A NEW SPECIES MEGALOMOIDEA WALLISERI (BIVALVIA) FROM THE SILURIAN OF ESTONIA","authors":"M. Isakar, I. Sinicyna","doi":"10.3176/geol.1993.3.04","DOIUrl":"https://doi.org/10.3176/geol.1993.3.04","url":null,"abstract":"","PeriodicalId":237994,"journal":{"name":"Proceedings of the Estonian Academy of Sciences. Geology","volume":"24 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133043326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
I. Fabricius, U. Korsbech, V. Rastenienė, A. Shogenova, S. Šliaupa
{"title":"Glauconitic rocks in the Baltic area: estimation of specific surface","authors":"I. Fabricius, U. Korsbech, V. Rastenienė, A. Shogenova, S. Šliaupa","doi":"10.3176/geol.2003.2.01","DOIUrl":"https://doi.org/10.3176/geol.2003.2.01","url":null,"abstract":"","PeriodicalId":237994,"journal":{"name":"Proceedings of the Estonian Academy of Sciences. Geology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133817714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
. A new modified Holocene stratigraphical chart for the continental and marine deposits is presented. The chronozone boundaries are correlated with those of the Nordic countries and instead of pollen zones pollen assemblage zones are proposed. As the latter are time-transgressive, they are not strictly bound up with the chronozones. For the marine deposits it is suggested to use local units until the acceptance of the generally approved standard subdivision.
{"title":"A NEW VERSION OF THE HOLOCENE STRATIGRAPHY IN ESTONIA","authors":"IN Estonia, A. Raukas, L. Saarse, S. Veski","doi":"10.3176/geol.1995.4.01","DOIUrl":"https://doi.org/10.3176/geol.1995.4.01","url":null,"abstract":". A new modified Holocene stratigraphical chart for the continental and marine deposits is presented. The chronozone boundaries are correlated with those of the Nordic countries and instead of pollen zones pollen assemblage zones are proposed. As the latter are time-transgressive, they are not strictly bound up with the chronozones. For the marine deposits it is suggested to use local units until the acceptance of the generally approved standard subdivision.","PeriodicalId":237994,"journal":{"name":"Proceedings of the Estonian Academy of Sciences. Geology","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133966326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：