Pub Date : 2021-01-01DOI: 10.5200/baltica.2021.1.7
B. Chubarenko, R. Boskachev
Potentially favourable conditions for overflows of water between the Vistula and Curonian lagoons via two branches of the Pregolya River were studied using water level data (2002–2007) at the hydrological stations located in lagoons and the river. The episodes (of two days and longer) of the ‘reversed slope’, when the water level in the Vistula Lagoon (7 cases) and the Curonian Lagoon (41 cases) was higher than in the river streams connecting them, were found. This confirms the theoretical possibility of water overflow between the Vistula and Curonian lagoons, back and forth. Some unusual cases (of two days and longer) when the ‘reverse slope’ of water level existed simultaneously in both recipient bodies (Vistula and Curonian lagoons) were also found. The analysis showed that wind conditions were not the single determining factor. Direct measurements of near-bottom currents showed that backward water flow appeared in both branches. Backward water flow developed mainly in the low parts of river branches, i.e. closer to the lagoons. Time delay in water flow variations and the appearance of backward water flow between downstream and upstream points was 2–7 hours, or about 4 hours on average. The signal of backward current in one branch penetrated upstream not only the other branch (correlation coefficient was about 0.64 and 0.71 for 1-h and 12-h running averaged series, respectively) but further upstream the mainstream of the Pregolya River.
{"title":"Hydraulic connection between Vistula and Curonian lagoons of the Baltic Sea","authors":"B. Chubarenko, R. Boskachev","doi":"10.5200/baltica.2021.1.7","DOIUrl":"https://doi.org/10.5200/baltica.2021.1.7","url":null,"abstract":"Potentially favourable conditions for overflows of water between the Vistula and Curonian lagoons via two branches of the Pregolya River were studied using water level data (2002–2007) at the hydrological stations located in lagoons and the river. The episodes (of two days and longer) of the ‘reversed slope’, when the water level in the Vistula Lagoon (7 cases) and the Curonian Lagoon (41 cases) was higher than in the river streams connecting them, were found. This confirms the theoretical possibility of water overflow between the Vistula and Curonian lagoons, back and forth. Some unusual cases (of two days and longer) when the ‘reverse slope’ of water level existed simultaneously in both recipient bodies (Vistula and Curonian lagoons) were also found. The analysis showed that wind conditions were not the single determining factor. Direct measurements of near-bottom currents showed that backward water flow appeared in both branches. Backward water flow developed mainly in the low parts of river branches, i.e. closer to the lagoons. Time delay in water flow variations and the appearance of backward water flow between downstream and upstream points was 2–7 hours, or about 4 hours on average. The signal of backward current in one branch penetrated upstream not only the other branch (correlation coefficient was about 0.64 and 0.71 for 1-h and 12-h running averaged series, respectively) but further upstream the mainstream of the Pregolya River.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70648351","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}
Pub Date : 2021-01-01DOI: 10.5200/baltica.2021.2.4
B. Adamovich, T. Mikheeva, H. Zhukava, E. Sorokovikova, A. Kuzmin, Galina Fedorova, R. Paskauskas, J. Karosienė
The 2011–2012 data on the hydrochemical mode of the transboundary River Viliya (Neris) and two of its tributaries in the territory of the Republic of Belarus and on structure of the phytoplankton community therein are presented. High phytoplankton biomass was determined in the summer period. For the first time, the presence of microcystin synthase genes (mcyE) was detected in the River Viliya (Neris), and four variants of microcystins were determined employing the MALDI-TOF method. Similarities in the species composition (including toxic species) of cyanobacteria from the River Viliya (Neris) and from the Curonian Lagoon of the Baltic Sea were noted. It can be assumed that the phytoplankton community structure of rivers can influence algal community formation in the downstream areas as well as in the coastal estuarine lagoons that eventually receive water from these rivers.
{"title":"Phytoplankton of the transboundary River Viliya (Neris): community structure and toxic cyanobacterial blooms","authors":"B. Adamovich, T. Mikheeva, H. Zhukava, E. Sorokovikova, A. Kuzmin, Galina Fedorova, R. Paskauskas, J. Karosienė","doi":"10.5200/baltica.2021.2.4","DOIUrl":"https://doi.org/10.5200/baltica.2021.2.4","url":null,"abstract":"The 2011–2012 data on the hydrochemical mode of the transboundary River Viliya (Neris) and two of its tributaries in the territory of the Republic of Belarus and on structure of the phytoplankton community therein are presented. High phytoplankton biomass was determined in the summer period. For the first time, the presence of microcystin synthase genes (mcyE) was detected in the River Viliya (Neris), and four variants of microcystins were determined employing the MALDI-TOF method. Similarities in the species composition (including toxic species) of cyanobacteria from the River Viliya (Neris) and from the Curonian Lagoon of the Baltic Sea were noted. It can be assumed that the phytoplankton community structure of rivers can influence algal community formation in the downstream areas as well as in the coastal estuarine lagoons that eventually receive water from these rivers.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70649216","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}
Pub Date : 2020-12-28DOI: 10.5200/baltica.2020.2.4
J. Satkūnas, Vytautas Minkevičius, R. Guobytė, A. Baubinienė, Rita Linkevičienė, J. Taminskas
The LiDAR-based digital elevation models of representative sample areas of morainic uplands of the Last (Weichselian) and pre-Last (Saalian) Glaciations in Lithuania were selected, and the terrain ruggedness index (TRI) and slope angles (SAs) were calculated. Former hypsometric studies of the topography in Lithuania were mainly dealing with the indication of maximum, minimum or average altitudes of relief derived from topographical maps. The SAs and TRI were calculated for the pattern areas (16 × 16 km) and their central smaller parts (5 × 5 km). In order to test how much morphometric parameters are dependent on the size of a sample area, smaller areas (located in the central parts of all five patterns) were analysed in a similar way, calculating SA and TRI values. The same order of the mean values of SAs was determined: the steepest slopes are characteristic of the Tauragnai, Plateliai and Vištytis patterns, and the gentlest slopes of the Varniai and Medininkai patterns. The steepest slopes and the highest TRI were determined for the marginal morainic uplands of the Last (Late Weichselian) Glaciation. The age of the insular Žemaičiai (Samogitian) Upland is under discussions so far. It was proposed by other researchers earlier that the core of the insular Žemaičiai Upland height formed during the Saalian Glaciation and this core is covered by a thin cover of Weichselian deposits. The morphometric parameters display that the highest maturity of the relief is characteristic of the southern slope of the insular Žemaičiai Upland and the Medininkai Upland of the Saalian age. This indicates a likely similar age of both uplands.
{"title":"Morphometric indicators of insular and marginal morainic uplands (based on LiDAR data) of the Last and pre-Last Glaciations, case of Lithuania","authors":"J. Satkūnas, Vytautas Minkevičius, R. Guobytė, A. Baubinienė, Rita Linkevičienė, J. Taminskas","doi":"10.5200/baltica.2020.2.4","DOIUrl":"https://doi.org/10.5200/baltica.2020.2.4","url":null,"abstract":"The LiDAR-based digital elevation models of representative sample areas of morainic uplands of the Last (Weichselian) and pre-Last (Saalian) Glaciations in Lithuania were selected, and the terrain ruggedness index (TRI) and slope angles (SAs) were calculated. Former hypsometric studies of the topography in Lithuania were mainly dealing with the indication of maximum, minimum or average altitudes of relief derived from topographical maps. The SAs and TRI were calculated for the pattern areas (16 × 16 km) and their central smaller parts (5 × 5 km). In order to test how much morphometric parameters are dependent on the size of a sample area, smaller areas (located in the central parts of all five patterns) were analysed in a similar way, calculating SA and TRI values. The same order of the mean values of SAs was determined: the steepest slopes are characteristic of the Tauragnai, Plateliai and Vištytis patterns, and the gentlest slopes of the Varniai and Medininkai patterns. The steepest slopes and the highest TRI were determined for the marginal morainic uplands of the Last (Late Weichselian) Glaciation. The age of the insular Žemaičiai (Samogitian) Upland is under discussions so far. It was proposed by other researchers earlier that the core of the insular Žemaičiai Upland height formed during the Saalian Glaciation and this core is covered by a thin cover of Weichselian deposits. The morphometric parameters display that the highest maturity of the relief is characteristic of the southern slope of the insular Žemaičiai Upland and the Medininkai Upland of the Saalian age. This indicates a likely similar age of both uplands.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2020-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42094115","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}
Pub Date : 2020-12-28DOI: 10.5200/baltica.2020.2.7
A. Jasinavičiūtė, D. Veteikis
The first state reserve in Lithuania was established in 1960; however, no detailed assessments of changes in the state of the protected values therein have been performed ever since. Landscape reserves are the most complex ones and they pursue the twofold goal – to conserve the values and to use them sustainably. In order to be resilient themselves, thus contributing to broader objectives of social-ecological resilience, the reserves should be able to adapt to ever-changing social and ecological conditions in a way that supports the long-term persistence of population, communities, and ecosystems of conservation concern. Therefore, it is necessary to update information on the status of values protected in the reserves. The article addresses this need by offering a concise and user-friendly methodology for assessing the status of landscape reserves. The methodology focuses on three main components: (1) general features of the landscape structure, (2) the effectiveness of protection of values and (3) the pressures and threats they experience. Two state landscape reserves were selected for testing the applicability of the methodology: one in Vilnius city, the other 50 km to the west, in the countryside. Application of the common methodology will allow to assess the condition of landscape reserves in the country. Further development of the methodology could include evaluation of external pressures (e.g. urbanization) as well as addition of remote sensing techniques.
{"title":"A new methodology to assess landscape reserves in Lithuania","authors":"A. Jasinavičiūtė, D. Veteikis","doi":"10.5200/baltica.2020.2.7","DOIUrl":"https://doi.org/10.5200/baltica.2020.2.7","url":null,"abstract":"The first state reserve in Lithuania was established in 1960; however, no detailed assessments of changes in the state of the protected values therein have been performed ever since. Landscape reserves are the most complex ones and they pursue the twofold goal – to conserve the values and to use them sustainably. In order to be resilient themselves, thus contributing to broader objectives of social-ecological resilience, the reserves should be able to adapt to ever-changing social and ecological conditions in a way that supports the long-term persistence of population, communities, and ecosystems of conservation concern. Therefore, it is necessary to update information on the status of values protected in the reserves. The article addresses this need by offering a concise and user-friendly methodology for assessing the status of landscape reserves. The methodology focuses on three main components: (1) general features of the landscape structure, (2) the effectiveness of protection of values and (3) the pressures and threats they experience. Two state landscape reserves were selected for testing the applicability of the methodology: one in Vilnius city, the other 50 km to the west, in the countryside. Application of the common methodology will allow to assess the condition of landscape reserves in the country. Further development of the methodology could include evaluation of external pressures (e.g. urbanization) as well as addition of remote sensing techniques.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2020-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48603767","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}
Pub Date : 2020-12-28DOI: 10.5200/baltica.2020.2.6
T. Tamošiūnas, Š. Skuodis, Gintaras Žaržojus
The surface of earth on the territory of Lithuania is covered by sediments of the Quaternary system, which are the object of human economic activities. Reliable assessment of sediment deformations is an important task of modern engineering geology and geotechnical engineering. The deformation of sediments is most often described using the modulus of deformation. The current article overviews different methods employed in deformation moduli determination and their application possibilities. The deformation moduli, which are used in various calculations, are usually calculated using correlation formulas and empirical coefficients. Thus, the obtained results may be inaccurate or completely unsuitable for further interpretation of the numerical situation. This article presents recommendations with regard to the use of various calculated deformation moduli in interpreting Lithuanian Quaternary system sediments.
{"title":"Overview of the Quaternary sediments deformation modulus dependence on testing methodology","authors":"T. Tamošiūnas, Š. Skuodis, Gintaras Žaržojus","doi":"10.5200/baltica.2020.2.6","DOIUrl":"https://doi.org/10.5200/baltica.2020.2.6","url":null,"abstract":"The surface of earth on the territory of Lithuania is covered by sediments of the Quaternary system, which are the object of human economic activities. Reliable assessment of sediment deformations is an important task of modern engineering geology and geotechnical engineering. The deformation of sediments is most often described using the modulus of deformation. The current article overviews different methods employed in deformation moduli determination and their application possibilities. The deformation moduli, which are used in various calculations, are usually calculated using correlation formulas and empirical coefficients. Thus, the obtained results may be inaccurate or completely unsuitable for further interpretation of the numerical situation. This article presents recommendations with regard to the use of various calculated deformation moduli in interpreting Lithuanian Quaternary system sediments.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2020-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42222534","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}
Pub Date : 2020-12-28DOI: 10.5200/baltica.2020.2.1
H.Ya. Havryshkiv, N. Radkovets
The Paleocene Yamna Formation represents one of the main oil-bearing sequences in the Ukrainian part of the Carpathian petroleum province. Major oil accumulations occur in the Boryslav-Pokuttya and Skyba Units of the Ukrainian Carpathians. In the great part of the study area, the Yamna Formation is made up of thick turbiditic sandstone layers functioning as reservoir rocks for oil and gas. The reconstructions of depositional environments of the Paleocene flysch deposits performed based on well log data, lithological and petrographic investigations showed that the terrigenous material was supplied into the sedimentary basin from two sources. One of them was located in the northwest of the study area and was characterized by the predominance of coarse-grained sandy sediments. Debris coming from the source located in its central part showed the predominance of clay muds and fine-grained psammitic material. The peculiarities of the terrigenous material distribution in the Paleocene sequence allowed singling out four areas with the maximum development (> 50% of the total section) of sandstones, siltstones and mudstones. The performed petrographic investigations and the estimation of reservoir properties of the Yamna Formation rocks in these four areas allowed establishing priority directions of further exploration works for hydrocarbons in the study territory.
{"title":"Paleocene deposits of the Ukrainian Carpathians: geological and petrographic characteristics, reservoir properties","authors":"H.Ya. Havryshkiv, N. Radkovets","doi":"10.5200/baltica.2020.2.1","DOIUrl":"https://doi.org/10.5200/baltica.2020.2.1","url":null,"abstract":"The Paleocene Yamna Formation represents one of the main oil-bearing sequences in the Ukrainian part of the Carpathian petroleum province. Major oil accumulations occur in the Boryslav-Pokuttya and Skyba Units of the Ukrainian Carpathians. In the great part of the study area, the Yamna Formation is made up of thick turbiditic sandstone layers functioning as reservoir rocks for oil and gas. The reconstructions of depositional environments of the Paleocene flysch deposits performed based on well log data, lithological and petrographic investigations showed that the terrigenous material was supplied into the sedimentary basin from two sources. One of them was located in the northwest of the study area and was characterized by the predominance of coarse-grained sandy sediments. Debris coming from the source located in its central part showed the predominance of clay muds and fine-grained psammitic material. The peculiarities of the terrigenous material distribution in the Paleocene sequence allowed singling out four areas with the maximum development (> 50% of the total section) of sandstones, siltstones and mudstones. The performed petrographic investigations and the estimation of reservoir properties of the Yamna Formation rocks in these four areas allowed establishing priority directions of further exploration works for hydrocarbons in the study territory.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2020-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47380020","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}
Pub Date : 2020-12-28DOI: 10.5200/baltica.2020.2.2
G. Motuza, S. Šliaupa
Numerous granitic intrusions occur along the southern margin of the Tajik Block and the Band-e-Bayan Zone in the Ghor Province of Central Afghanistan. Previously, they used to be linked to the Cimmerian igneous episodes of Triassic and Cretaceous ages. However, the new U-Pb dating has revealed that these granite intrusions occurred during the Eocene within a narrow time span of 41–36 Ma. They are related to the number of local depressions filled with the volcanic-sedimentary sequence of the same age. These data indicate an intense short-termed magmatic event that affected the region in the Palaeogene. The magmatism might be related to the India-Eurasia collision, which started approximately at the same time. It is likely to have induced the horizontal displacement of crustal blocks westwards along the Hari Rod fault.
{"title":"Palaeogene plutonic magmatism in Central Afghanistan, and its relation to the India-Eurasia collision","authors":"G. Motuza, S. Šliaupa","doi":"10.5200/baltica.2020.2.2","DOIUrl":"https://doi.org/10.5200/baltica.2020.2.2","url":null,"abstract":"Numerous granitic intrusions occur along the southern margin of the Tajik Block and the Band-e-Bayan Zone in the Ghor Province of Central Afghanistan. Previously, they used to be linked to the Cimmerian igneous episodes of Triassic and Cretaceous ages. However, the new U-Pb dating has revealed that these granite intrusions occurred during the Eocene within a narrow time span of 41–36 Ma. They are related to the number of local depressions filled with the volcanic-sedimentary sequence of the same age. These data indicate an intense short-termed magmatic event that affected the region in the Palaeogene. The magmatism might be related to the India-Eurasia collision, which started approximately at the same time. It is likely to have induced the horizontal displacement of crustal blocks westwards along the Hari Rod fault.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2020-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45484711","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}
Pub Date : 2020-12-28DOI: 10.5200/baltica.2020.2.5
O. Korsakova, D. Tolstobrov, S. Nikolaeva, V. Kolka, A. Tolstobrova
The paper summarizes the evidence of litho-, biostratigraphy and 14C dating of sedimentary sequences studied in natural outcrops and bottom deposits in small lakes, as well as data on coastal morphology in the depressions of Ekostrovskaya and Babinskaya Imandra, the southern sub-basins of Lake Imandra. Lithological, 14C and diatom data suggest that the brackish-water reservoir followed by the fresh-water one existed in the Ekostrovskaya Imandra depression during the Younger Dryas chronozone prior to 11,400cal. yr BP. The Fennoscandian Ice Sheet margin is assumed to have been located in the Lake Imandra basin, covering western Babinskaya Imandra earlier than c. 10,250 cal. yr BP. The early Holocene c. 11,400–8,500 cal. yr BP was marked by a significant westward retreat of the ice margin in the western Lake Imandra depression and adjacent areas, and an extensive fresh-water pra-Imandra Lake basin was formed there. At the end of the Preboreal, earlier than c. 9,210–8,500 cal. yr BP, the pra-Imandra Lake coastline was at least 16–18 m higher than the modern one, as can be assumed according to coastal morphology and lithostratigraphical data. The coastline of that reservoir changed, water square slightly reduced, and isolated small lakes emerged on coasts during the early Holocene.
本文总结了小型湖泊自然露头和底沉积的岩性、生物地层学和沉积层序的14C定年证据，以及伊曼德拉湖南部亚盆地Ekostrovskaya和Babinskaya Imandra凹陷的海岸形态资料。岩石学、14C和硅藻资料表明，在新仙女木期之前，Ekostrovskaya Imandra凹陷存在咸淡水储层，之后是淡水储层。年英国石油公司。据推测，芬诺斯坎德冰盖边缘位于伊曼德拉湖盆地，覆盖了巴宾斯卡亚伊曼德拉湖西部，时间早于约10,250 cal. yr BP。全新世早期(约11400 ~ 8500 cal. yr BP)以伊曼德拉湖坳陷西部及邻近地区冰缘向西退缩为标志，形成了广阔的普拉-伊曼德拉淡水湖盆地。根据海岸形态和岩石地层资料推测，在前寒武纪末期，早于约9,210 ~ 8,500 cal. yr BP，普拉-伊曼德拉湖的海岸线比现代海岸线至少高出16 ~ 18 m。在全新世早期，该水库的海岸线发生了变化，水域面积略有减少，海岸上出现了孤立的小湖泊。
{"title":"Lake Imandra depression in the Late Glacial and early Holocene (Kola Peninsula, north-western Russia)","authors":"O. Korsakova, D. Tolstobrov, S. Nikolaeva, V. Kolka, A. Tolstobrova","doi":"10.5200/baltica.2020.2.5","DOIUrl":"https://doi.org/10.5200/baltica.2020.2.5","url":null,"abstract":"The paper summarizes the evidence of litho-, biostratigraphy and 14C dating of sedimentary sequences studied in natural outcrops and bottom deposits in small lakes, as well as data on coastal morphology in the depressions of Ekostrovskaya and Babinskaya Imandra, the southern sub-basins of Lake Imandra. Lithological, 14C and diatom data suggest that the brackish-water reservoir followed by the fresh-water one existed in the Ekostrovskaya Imandra depression during the Younger Dryas chronozone prior to 11,400cal. yr BP. The Fennoscandian Ice Sheet margin is assumed to have been located in the Lake Imandra basin, covering western Babinskaya Imandra earlier than c. 10,250 cal. yr BP. The early Holocene c. 11,400–8,500 cal. yr BP was marked by a significant westward retreat of the ice margin in the western Lake Imandra depression and adjacent areas, and an extensive fresh-water pra-Imandra Lake basin was formed there. At the end of the Preboreal, earlier than c. 9,210–8,500 cal. yr BP, the pra-Imandra Lake coastline was at least 16–18 m higher than the modern one, as can be assumed according to coastal morphology and lithostratigraphical data. The coastline of that reservoir changed, water square slightly reduced, and isolated small lakes emerged on coasts during the early Holocene.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2020-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43085858","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}
Pub Date : 2020-12-28DOI: 10.5200/baltica.2020.2.3
S. Šliaupa, J. Lazauskienė, Saulius Lozovskis, R. Šliaupienė
There is little known of the basic parameters of the Lower Silurian graptolitic black shales that are considered the most prospective unconventional gas reservoir in west Lithuania, situated in the deep central part of the Baltic sedimentary basin. Hundreds of deep oil exploration wells have been drilled in the area of interest, owing to extensive exploration of oil fields. The lower and middle Llandovery interval was mainly drilled with coring, while most of the section was covered by only logging. Therefore, the knowledge of major parameters of the Lower Silurian shales is rather obscure and is based on scarce rock sample data. The gamma-ray, electrical resistivity and sonic logs were utilised, together with mineralogical studies of rock samples to document vertical and lateral distribution of organic matter. Also, the brittleness index was defined to characterise the whole Lower Silurian section. Some unexpected trends were identified that may redirect exploration strategy in west Lithuania. The combined application of mineralogical studies and well logs indicate a much higher exploitation quality of the Lower Silurian shales than previously believed. A higher organic matter content and brittleness were derived from logging data in the Lower Silurian shales.
{"title":"Distribution of organic matter and evaluation of brittleness index of the Lower Silurian shales of west Lithuania based on interpretation of well logs","authors":"S. Šliaupa, J. Lazauskienė, Saulius Lozovskis, R. Šliaupienė","doi":"10.5200/baltica.2020.2.3","DOIUrl":"https://doi.org/10.5200/baltica.2020.2.3","url":null,"abstract":"There is little known of the basic parameters of the Lower Silurian graptolitic black shales that are considered the most prospective unconventional gas reservoir in west Lithuania, situated in the deep central part of the Baltic sedimentary basin. Hundreds of deep oil exploration wells have been drilled in the area of interest, owing to extensive exploration of oil fields. The lower and middle Llandovery interval was mainly drilled with coring, while most of the section was covered by only logging. Therefore, the knowledge of major parameters of the Lower Silurian shales is rather obscure and is based on scarce rock sample data. The gamma-ray, electrical resistivity and sonic logs were utilised, together with mineralogical studies of rock samples to document vertical and lateral distribution of organic matter. Also, the brittleness index was defined to characterise the whole Lower Silurian section. Some unexpected trends were identified that may redirect exploration strategy in west Lithuania. The combined application of mineralogical studies and well logs indicate a much higher exploitation quality of the Lower Silurian shales than previously believed. A higher organic matter content and brittleness were derived from logging data in the Lower Silurian shales.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2020-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46418585","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}
Pub Date : 2020-08-01DOI: 10.5200/BALTICA.2020.1.9
Roksana Kruć, K. Dragon, J. Górski, Zsuzsanna Nagy-Kovács, T. Grischek
Managed aquifer recharge is gaining in importance worldwide. As there is not much information on bank filtration (BF) sites in Eastern Europe, a survey of geohydraulic conditions and post-treatment schemes carried out. Such information will make it possible to assess hydraulic conditions in the region and the commonly required post-treatment. Data were collected from publications, archival documentations, maps as well as through direct communication with administrators of relevant water companies. As a result, a summary of the data from 71 BF or BF/artificial recharge (AR) well fields in the Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Romania, Russia, Serbia, Slovakia and Slovenia was prepared. Data on the source of water, location, capacity, aquifer thickness and hydraulic conductivity, and treatment methods were collected. Thirteen of the studied 71 RBF well fields are combined with AR. The most common type of BF in Eastern Europe is riverbank filtration (RBF) with wells located along a river. 56% of the analyzed sites are located along larger rivers such as the Danube, Drava, Nemunas, Neris, Odra, Volga, Warta and the Wisła. The smallest BF site has a discharge capacity of only 38 m3/day, the largest BF site 210,000 m3/day, while the smallest and the largest combined BF/AR site has a discharge capacity of 5,500 m3/day and 150,000 m3/day, respectively. The average values of aquifer thickness and hydraulic conductivity are 21 m and 2.7*10-3 m/s, respectively, at BF sites and 16 m and 5.7*10-4 m/s, respectively, at BF/AR sites. The most common post-treatment steps include aeration-filtration – disinfection, UV, ozone and activated carbon being used at many sites as well. The collected data can prove helpful in designing and modernizing BF sites, comparing and establishing direct contacts with water companies facing similar conditions. The outcome of this study is the built-up BF database for Eastern Europe, which can supplement the Global Inventory of Managed Aquifer Recharge Schemes (IGRAC 2017)
{"title":"Geohydraulic conditions and post-treatment at riverbank filtration sites in Eastern Europe","authors":"Roksana Kruć, K. Dragon, J. Górski, Zsuzsanna Nagy-Kovács, T. Grischek","doi":"10.5200/BALTICA.2020.1.9","DOIUrl":"https://doi.org/10.5200/BALTICA.2020.1.9","url":null,"abstract":"Managed aquifer recharge is gaining in importance worldwide. As there is not much information on bank filtration (BF) sites in Eastern Europe, a survey of geohydraulic conditions and post-treatment schemes carried out. Such information will make it possible to assess hydraulic conditions in the region and the commonly required post-treatment. Data were collected from publications, archival documentations, maps as well as through direct communication with administrators of relevant water companies. As a result, a summary of the data from 71 BF or BF/artificial recharge (AR) well fields in the Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Romania, Russia, Serbia, Slovakia and Slovenia was prepared. Data on the source of water, location, capacity, aquifer thickness and hydraulic conductivity, and treatment methods were collected. Thirteen of the studied 71 RBF well fields are combined with AR. The most common type of BF in Eastern Europe is riverbank filtration (RBF) with wells located along a river. 56% of the analyzed sites are located along larger rivers such as the Danube, Drava, Nemunas, Neris, Odra, Volga, Warta and the Wisła. The smallest BF site has a discharge capacity of only 38 m3/day, the largest BF site 210,000 m3/day, while the smallest and the largest combined BF/AR site has a discharge capacity of 5,500 m3/day and 150,000 m3/day, respectively. The average values of aquifer thickness and hydraulic conductivity are 21 m and 2.7*10-3 m/s, respectively, at BF sites and 16 m and 5.7*10-4 m/s, respectively, at BF/AR sites. The most common post-treatment steps include aeration-filtration – disinfection, UV, ozone and activated carbon being used at many sites as well. The collected data can prove helpful in designing and modernizing BF sites, comparing and establishing direct contacts with water companies facing similar conditions. The outcome of this study is the built-up BF database for Eastern Europe, which can supplement the Global Inventory of Managed Aquifer Recharge Schemes (IGRAC 2017)","PeriodicalId":55401,"journal":{"name":"Baltica","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44673273","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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