Pub Date : 2022-01-01DOI: 10.5200/baltica.2022.2.1
Gabrielė Gudaitienė, G. Motuza, M. Stančikaitė, R. Pukienė, D. Kisielienė, J. Mažeika, Tomas Čelkis, Dovilė Baltramiejūnaitė, Ž. Ežerinskis
This paper presents results of the interdisciplinary investigations into the ancient wooden construction, presumably, a well, discovered near the Pamerkiai village, south-eastern Lithuania. The study aims at ascertaining the context (specific geological-geomorphological situation and the habitation history of this territory) of this comparably well-preserved and very uncommon find. The discovered wooden construction and its environment were investigated applying a multi-disciplinary approach combining the archaeological survey, which includes analysis of the collected artefacts, the dendrological examination of the timber used for construction, investigations of the plant macroremains and pollen found in the infilling material, and the 14C dating (conventional and AMS) of the organic material; and the geological-geomorphological characterization of the site. A new perspective to gain data about the infrastructure that might have existed in the area in the 15th century is provided: the integrated and interdisciplinary research is believed to reveal the natural and anthropogenic context. A discussion on the feasibility of tracing the origins of the modern Pamerkiai village is generated. It is alternatively hypothesized that the discovered wooden construction is part of the stopover place on the highroad that has been archaeologically unexplored.
{"title":"New insights into the medieval history of a non-urban territory: multidisciplinary investigations in SE Lithuania","authors":"Gabrielė Gudaitienė, G. Motuza, M. Stančikaitė, R. Pukienė, D. Kisielienė, J. Mažeika, Tomas Čelkis, Dovilė Baltramiejūnaitė, Ž. Ežerinskis","doi":"10.5200/baltica.2022.2.1","DOIUrl":"https://doi.org/10.5200/baltica.2022.2.1","url":null,"abstract":"This paper presents results of the interdisciplinary investigations into the ancient wooden construction, presumably, a well, discovered near the Pamerkiai village, south-eastern Lithuania. The study aims at ascertaining the context (specific geological-geomorphological situation and the habitation history of this territory) of this comparably well-preserved and very uncommon find. The discovered wooden construction and its environment were investigated applying a multi-disciplinary approach combining the archaeological survey, which includes analysis of the collected artefacts, the dendrological examination of the timber used for construction, investigations of the plant macroremains and pollen found in the infilling material, and the 14C dating (conventional and AMS) of the organic material; and the geological-geomorphological characterization of the site. A new perspective to gain data about the infrastructure that might have existed in the area in the 15th century is provided: the integrated and interdisciplinary research is believed to reveal the natural and anthropogenic context. A discussion on the feasibility of tracing the origins of the modern Pamerkiai village is generated. It is alternatively hypothesized that the discovered wooden construction is part of the stopover place on the highroad that has been archaeologically unexplored.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":"1 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70649052","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 : 2022-01-01DOI: 10.5200/baltica.2022.1.1
J. Jarzyna, P. Krakowska-Madejska, E. Puskarczyk, K. Wawrzyniak-Guz
This paper presents findings from the study into the relationships between the laboratory- and well log-derived data (including the comprehensive well-log interpretation data) on petrophysical properties of the Silurian and Ordovician shale gas formations in the Baltic Basin (North Poland). Approximately 70 samples of mudstone were examined in laboratory experiments to determine total and effective porosity; bulk, grain, and rock density; total organic carbon; physical permeability; total pore area, pore distribution; and mineral components. Some rock samples were further investigated using mercury injection porosimetry, helium porosimetry, dual liquid porosimetry, NMR, N2 adsorption/desorption, rock-eval pyrolysis, and XRD to obtain the targeted petrophysical information from heterogeneous claystone/mudstone and their organic matter. Natural radioactivity, bulk density, total porosity, volume of kerogen, and other parameters were determined from the continuous curves plotted from the earlier depth matched well logging data, which were used to account for differences between vertical resolution of well logs and the point data obtained from the laboratory. The goal of this study was to provide a comprehensive characterization of the Silurian and Ordovician shale gas formations in Northern Poland to support the thesis about their heterogeneity.
{"title":"Petrophysical characteristics of Silurian and Ordovician shale gas formations in the Baltic Basin (Northern Poland)","authors":"J. Jarzyna, P. Krakowska-Madejska, E. Puskarczyk, K. Wawrzyniak-Guz","doi":"10.5200/baltica.2022.1.1","DOIUrl":"https://doi.org/10.5200/baltica.2022.1.1","url":null,"abstract":"This paper presents findings from the study into the relationships between the laboratory- and well log-derived data (including the comprehensive well-log interpretation data) on petrophysical properties of the Silurian and Ordovician shale gas formations in the Baltic Basin (North Poland). Approximately 70 samples of mudstone were examined in laboratory experiments to determine total and effective porosity; bulk, grain, and rock density; total organic carbon; physical permeability; total pore area, pore distribution; and mineral components. Some rock samples were further investigated using mercury injection porosimetry, helium porosimetry, dual liquid porosimetry, NMR, N2 adsorption/desorption, rock-eval pyrolysis, and XRD to obtain the targeted petrophysical information from heterogeneous claystone/mudstone and their organic matter. Natural radioactivity, bulk density, total porosity, volume of kerogen, and other parameters were determined from the continuous curves plotted from the earlier depth matched well logging data, which were used to account for differences between vertical resolution of well logs and the point data obtained from the laboratory. The goal of this study was to provide a comprehensive characterization of the Silurian and Ordovician shale gas formations in Northern Poland to support the thesis about their heterogeneity.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":"1 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70649039","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 : 2022-01-01DOI: 10.5200/baltica.2022.2.4
V. Jakimavičiūtė-Maselienė, V. Samalavičius, Arina Ašipauskaitė, Adrian Guščo
In this study, a salt-tracer method applicability in Quaternary aquifer system groundwater was tested. The tracer experiment was performed in Vilnius University Kairėnai polygon for hydrogeological investigations in 2021. In Lithuania, experiments with tracers are not prevalent. Therefore, this work describes the practical use of the tracer for the analysis of the hydrogeological environment, a methodology that enables experiments with salt tracers. After the tracer test, the water flow rate was calculated at the time of the peak concentration of Cl-, which reached 9.41 m/d. The effective porosity value was calculated manually (0.16) and using TRAC code (0.1389 and 0.1341; normalized for background values). The main results of tracer experiments show that sodium chloride solution is effective as a tracer in the Quaternary aquifer system of Lithuania for actual nef calculation, where aquifer hydraulic conductivity values are similar to the studied area. Tracer peak analysis performed in this study confirms a possibility of estimating the heterogeneity of aquifer nef on site.
{"title":"Estimation of hydrogeological parameters of porous media in a radially convergent flow field in Kairėnai polygon, SE Lithuania","authors":"V. Jakimavičiūtė-Maselienė, V. Samalavičius, Arina Ašipauskaitė, Adrian Guščo","doi":"10.5200/baltica.2022.2.4","DOIUrl":"https://doi.org/10.5200/baltica.2022.2.4","url":null,"abstract":"In this study, a salt-tracer method applicability in Quaternary aquifer system groundwater was tested. The tracer experiment was performed in Vilnius University Kairėnai polygon for hydrogeological investigations in 2021. In Lithuania, experiments with tracers are not prevalent. Therefore, this work describes the practical use of the tracer for the analysis of the hydrogeological environment, a methodology that enables experiments with salt tracers. After the tracer test, the water flow rate was calculated at the time of the peak concentration of Cl-, which reached 9.41 m/d. The effective porosity value was calculated manually (0.16) and using TRAC code (0.1389 and 0.1341; normalized for background values). The main results of tracer experiments show that sodium chloride solution is effective as a tracer in the Quaternary aquifer system of Lithuania for actual nef calculation, where aquifer hydraulic conductivity values are similar to the studied area. Tracer peak analysis performed in this study confirms a possibility of estimating the heterogeneity of aquifer nef on site.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":"1 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70649177","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 : 2022-01-01DOI: 10.5200/baltica.2022.2.3
O. Davydov, Viktoras Karaliunas
In the coastal zone of the oceans, coastal barriers are quite widespread. Within their limits, inlets periodically arise and exist for a certain time, which is of great geological, hydrological, ecological, and navigational significance. Along the coasts where tidal fluctuations predominate, tidal inlets stand out, which are quite well studied in terms of genesis, morpho-, hydro- and litho-dynamics. Inland, semi-isolated marine basins, where tidal fluctuations do not reach a significant amplitude, are called non-tidal seas. Within the coastal barriers of non-tidal seas, channels periodically arise and develop, which are called breaches or prorvas. Breaches are quite often mentioned in the specialized literature along the coasts of non-tidal seas, but they have not been purposefully studied. In this article, we tried to analyze the conditions for the formation of prorvas within non-tidal seas based on many years of research. We have identified four hydrodynamic situations in which breaches are formed. The presented variety of situations allows us to identify and describe four genetic types of prorvas: storm-generated, storm-surge-generated, wind-stress-generated, and river-stress (fluvially induced). The presented article is the first attempt to analyze the genetic characteristics of the breaches.
{"title":"Genetic diversity of inlet systems along non-tidal coasts: examples from the Black Sea and Sea of Azov (Ukraine)","authors":"O. Davydov, Viktoras Karaliunas","doi":"10.5200/baltica.2022.2.3","DOIUrl":"https://doi.org/10.5200/baltica.2022.2.3","url":null,"abstract":"In the coastal zone of the oceans, coastal barriers are quite widespread. Within their limits, inlets periodically arise and exist for a certain time, which is of great geological, hydrological, ecological, and navigational significance. Along the coasts where tidal fluctuations predominate, tidal inlets stand out, which are quite well studied in terms of genesis, morpho-, hydro- and litho-dynamics. Inland, semi-isolated marine basins, where tidal fluctuations do not reach a significant amplitude, are called non-tidal seas. Within the coastal barriers of non-tidal seas, channels periodically arise and develop, which are called breaches or prorvas. Breaches are quite often mentioned in the specialized literature along the coasts of non-tidal seas, but they have not been purposefully studied. In this article, we tried to analyze the conditions for the formation of prorvas within non-tidal seas based on many years of research. We have identified four hydrodynamic situations in which breaches are formed. The presented variety of situations allows us to identify and describe four genetic types of prorvas: storm-generated, storm-surge-generated, wind-stress-generated, and river-stress (fluvially induced). The presented article is the first attempt to analyze the genetic characteristics of the breaches.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":"1 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70649170","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.2021.1.8
V. Nikulins, D. Malytskyy
The focal-mechanism solution for the second shock of the Kaliningrad earthquake on 21 September 2004 (13:32 UTC) with a magnitude of Mw 5.2 was obtained using the waveform inversion (WFI) method. The method was used with the aim of its subsequent application as a discriminator in the East Baltic region for recognizing the genesis of seismic events based on data from a limited number of stations. The WFI method was tested by broadband channels. The results of focal-mechanism solution (strike = 119°; dip = 73°; rake = –163°) allowed (1) to state the source mechanism as a right-lateral strike-slip, (2) to estimate the optimal source depth equal to 3.0 km, and (3) to estimate the parameters of the compression axes (Paz = 340°; Ppl = 29°), tension (Taz = 252°; Tpl = 1°) and the axis coinciding with the intersection of two nodal planes (Baz = 162°; Bpl = 66°). These results are in satisfactory agreement with the results of the leading seismological agencies. Seismotectonic analysis showed that the epicentre of the earthquake is located inside the structure formed by the Yantarnensk fault zone and the zone of the Bakalinsk ruptured flexure. The WFI method showed its potential use as a discriminator of the genesis of seismic events.
{"title":"Focal mechanism of the Kaliningrad earthquake of 21 September 2004 based on waveform inversion using a limited number of stations","authors":"V. Nikulins, D. Malytskyy","doi":"10.5200/baltica.2021.1.8","DOIUrl":"https://doi.org/10.5200/baltica.2021.1.8","url":null,"abstract":"The focal-mechanism solution for the second shock of the Kaliningrad earthquake on 21 September 2004 (13:32 UTC) with a magnitude of Mw 5.2 was obtained using the waveform inversion (WFI) method. The method was used with the aim of its subsequent application as a discriminator in the East Baltic region for recognizing the genesis of seismic events based on data from a limited number of stations. The WFI method was tested by broadband channels. The results of focal-mechanism solution (strike = 119°; dip = 73°; rake = –163°) allowed (1) to state the source mechanism as a right-lateral strike-slip, (2) to estimate the optimal source depth equal to 3.0 km, and (3) to estimate the parameters of the compression axes (Paz = 340°; Ppl = 29°), tension (Taz = 252°; Tpl = 1°) and the axis coinciding with the intersection of two nodal planes (Baz = 162°; Bpl = 66°). These results are in satisfactory agreement with the results of the leading seismological agencies. Seismotectonic analysis showed that the epicentre of the earthquake is located inside the structure formed by the Yantarnensk fault zone and the zone of the Bakalinsk ruptured flexure. The WFI method showed its potential use as a discriminator of the genesis of seismic events.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":"1 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70647921","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.2021.1.10
L. Balakauskas, G. Vaikutienė, M. Paškevičiūtė, V. Valskys, A. Spiridonov
High spatial resolution diatom and loss-on-ignition analyses were carried out on the surface sediments of a shallow, medium-sized lake in north-eastern Lithuania to examine the degree of spatial heterogeneity of diatom assemblages in the lake, as well as the influence of water depth on diatom compositions. The compositional properties of sediments and diatom assemblages show a strong relationship with water depth; some less prominent changes were attributed to the tributary catchment. Diatom assemblage compositions are rather homogenous throughout the lake (Morisita-Horn similarity indices make >0.9 in most locations of the lake, in relation to others), especially in its deeper parts. Our case shows that the most representative point does not lie in the centre of the lake, as it is assumed in most of fossil studies. Studies of spatial heterogeneity of modern diatoms can facilitate site selection and fossil diatom data interpretation.
{"title":"Effects of spatial heterogeneity on the estimation of diatom assemblage composition: an example of Lake Imbradas (NE Lithuania)","authors":"L. Balakauskas, G. Vaikutienė, M. Paškevičiūtė, V. Valskys, A. Spiridonov","doi":"10.5200/baltica.2021.1.10","DOIUrl":"https://doi.org/10.5200/baltica.2021.1.10","url":null,"abstract":"High spatial resolution diatom and loss-on-ignition analyses were carried out on the surface sediments of a shallow, medium-sized lake in north-eastern Lithuania to examine the degree of spatial heterogeneity of diatom assemblages in the lake, as well as the influence of water depth on diatom compositions. The compositional properties of sediments and diatom assemblages show a strong relationship with water depth; some less prominent changes were attributed to the tributary catchment. Diatom assemblage compositions are rather homogenous throughout the lake (Morisita-Horn similarity indices make >0.9 in most locations of the lake, in relation to others), especially in its deeper parts. Our case shows that the most representative point does not lie in the centre of the lake, as it is assumed in most of fossil studies. Studies of spatial heterogeneity of modern diatoms can facilitate site selection and fossil diatom data interpretation.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":"1 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70648254","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.2021.2.2
D. Bagočius, O. Anne, Aleksas Narscius
One of the United Nations Sustainable Development Goals regarding “conservation and sustainable use of the oceans, seas, and marine resources” emphasizes the urgency of eliminating harmful effects on the sea and its biota, where the role of anthropogenic activities is crucial. The global trend of merchant shipping is increasing, thus enlarging underwater noise levels. As a result, greater noise can harm aquatic animals in their habitats. In the Baltic Sea, the underwater sound pressure levels are now being evaluated utilizing noise measurement, modelling, and mapping. In areas such as narrow ship passages, namely lagoons, channels, or straits, the ambient underwater noise modelling becomes very complex, even though these EU inland waters are regarded by legislation as part of the marine basin. For instance, the Klaipėda Channel (Klaipėda Strait), connecting the Baltic Sea and the Curonian Lagoon, is regarded by the national Lithuanian legislation as part of marine waters, where the environmental status should be evaluated according to the EU Maritime Strategy Framework Directive. In this narrow channel, an alternative to the modelling of ambient sound pressure levels can be applied to understand the long-term trends of vessel-sourced noise emissions. In this paper, an example of application of ship noise emission modelling for a narrow Klaipėda Harbour area is presented, along with the results obtained throughout 2015–2017. The modelled noise levels in the harbour area reached the median levels of 112.5 dB in 2015 and 102.6 dB re 1 µPa2 in 2017. The maximum emitted instantaneous sound pressure levels by ships reached 173.7 dB in 2015 and 179.4 dB re 1 µPa2 in 2017 in the area of interest.
联合国关于“保护和可持续利用海洋和海洋资源”的可持续发展目标之一强调了消除对海洋及其生物群有害影响的紧迫性，因为人为活动在其中的作用至关重要。全球商船的发展趋势日益增加，从而加大了水下噪声水平。因此，更大的噪音会伤害水生动物的栖息地。在波罗的海，目前正在利用噪声测量、建模和绘图来评估水下声压级。在狭窄的船舶通道，即泻湖、水道或海峡等区域，环境水下噪声建模变得非常复杂，即使这些欧盟内陆水域被立法视为海洋盆地的一部分。例如，连接波罗的海和库尔尼泻湖的Klaipėda海峡(Klaipėda海峡)被立陶宛国家立法视为海洋水域的一部分，应根据欧盟海洋战略框架指令对其环境状况进行评估。在这个狭窄的通道中，可以采用一种替代环境声压级建模的方法来了解船舶源噪声排放的长期趋势。本文以Klaipėda狭窄港区船舶噪声排放模型为例，给出了2015-2017年的研究结果。海港地区的模拟噪声水平在2015年达到112.5 dB的中位数水平，在2017年达到102.6 dB / 1µPa2。研究区域船舶最大瞬时声压级在2015年达到173.7 dB, 2017年达到179.4 dB / 1µPa2。
{"title":"Modelling of underwater noise emissions by ships in Klaipėda Strait, Lithuania","authors":"D. Bagočius, O. Anne, Aleksas Narscius","doi":"10.5200/baltica.2021.2.2","DOIUrl":"https://doi.org/10.5200/baltica.2021.2.2","url":null,"abstract":"One of the United Nations Sustainable Development Goals regarding “conservation and sustainable use of the oceans, seas, and marine resources” emphasizes the urgency of eliminating harmful effects on the sea and its biota, where the role of anthropogenic activities is crucial. The global trend of merchant shipping is increasing, thus enlarging underwater noise levels. As a result, greater noise can harm aquatic animals in their habitats. In the Baltic Sea, the underwater sound pressure levels are now being evaluated utilizing noise measurement, modelling, and mapping. In areas such as narrow ship passages, namely lagoons, channels, or straits, the ambient underwater noise modelling becomes very complex, even though these EU inland waters are regarded by legislation as part of the marine basin. For instance, the Klaipėda Channel (Klaipėda Strait), connecting the Baltic Sea and the Curonian Lagoon, is regarded by the national Lithuanian legislation as part of marine waters, where the environmental status should be evaluated according to the EU Maritime Strategy Framework Directive. In this narrow channel, an alternative to the modelling of ambient sound pressure levels can be applied to understand the long-term trends of vessel-sourced noise emissions. In this paper, an example of application of ship noise emission modelling for a narrow Klaipėda Harbour area is presented, along with the results obtained throughout 2015–2017. The modelled noise levels in the harbour area reached the median levels of 112.5 dB in 2015 and 102.6 dB re 1 µPa2 in 2017. The maximum emitted instantaneous sound pressure levels by ships reached 173.7 dB in 2015 and 179.4 dB re 1 µPa2 in 2017 in the area of interest.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":"60 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70649083","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.2021.2.6
S. Gadal, T. Gloaguen
In recent years, Latvian, Lithuanian, and the Oblast of Kaliningrad coastal zones have been experiencing a particularly intense and rapid anthropisation of the coastline due to political, social, and economic changes at the end of the Soviet period. These pressures are exerting on a highly sensitive environment, which has remained relatively untouched by any major development due to the militarisation of the coasts. The human stakes increased considerably in the coastal zone of the south-eastern Baltic with tourism, industrial development, and urban expansion. The environmental impacts and issues of the post-soviet anthropisation are analysed in this article through a bibliographic compilation related to the evolution of the coastal management policies reconciling environmental protection and economic development.
{"title":"Environmental issues in the coastal regions of the south-eastern Baltic Sea: A sensitive natural environment in the face of increasing anthropic pressures","authors":"S. Gadal, T. Gloaguen","doi":"10.5200/baltica.2021.2.6","DOIUrl":"https://doi.org/10.5200/baltica.2021.2.6","url":null,"abstract":"In recent years, Latvian, Lithuanian, and the Oblast of Kaliningrad coastal zones have been experiencing a particularly intense and rapid anthropisation of the coastline due to political, social, and economic changes at the end of the Soviet period. These pressures are exerting on a highly sensitive environment, which has remained relatively untouched by any major development due to the militarisation of the coasts. The human stakes increased considerably in the coastal zone of the south-eastern Baltic with tourism, industrial development, and urban expansion. The environmental impacts and issues of the post-soviet anthropisation are analysed in this article through a bibliographic compilation related to the evolution of the coastal management policies reconciling environmental protection and economic development.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":"1 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70649274","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.2021.2.5
I. Javakhishvili, D. Shengelia, T. Tsutsunava, G. Chichinadze, G. Beridze, L. Shumlyanskyy
The Dizi Series is exposed within the Southern Slope zone of the Greater Caucasus, in the core of the Svaneti anticlinorium. It is mainly composed of terrigenous, volcanogenic and carbonate rocks faunistically dated from the Devonian to the Triassic inclusive. Regional and contact metamorphism of the Dizi Series rocks was studied. It is stated that the degree of regional metamorphism corresponds to the chlorite-sericite subfacies of the greenschist facies, occurring at a temperature of 300–350°C and a pressure of 1.5–2.3 kbar. As a result of the action of the Middle Jurassic intrusive rock bodies, the regionally metamorphosed rocks of the Dizi Series underwent contact metamorphism. Three zones of contact metamorphism were distinguished corresponding to albite-epidote-hornfels, andalusite-biotite-muscovite-chlorite-hornfels and andalusite-biotite-muscovite-hornfels subfacies. Contact metamorphism took place at a significantly higher temperature and lower pressure than the preceding regional metamorphism. The maximum temperature of the contact metamorphism reached ≈ 570°С, while pressure varied within the range of ≈ 0.3–0.8 kbar. The evolution of rock associations of regional and contact metamorphism of the Dizi Series was studied. The fields of facies and subfacies of regional and contact metamorphism are shown in the Ps-T diagram. Three age populations of zircons were identified using U-Pb LA-ICP-MS dating of the diorite-porphyrite intrusion in the Dizi Series: Zrn1 (ca. 2200 Ma) and Zrn2 (458 ± 29 Ma) that were captured by the diorite-porphyrite magma from the ancient magmatic and metamorphic rocks of the crystalline basement, and Zrn3 (166.5 ± 4.6 Ma) that corresponds to the age of diorite-porphyrite crystallization.
{"title":"Metamorphism of the Dizi Series Rocks (the Greater Caucasus): Petrography, Mineralogy and Evolution of Metamorphic Assemblages","authors":"I. Javakhishvili, D. Shengelia, T. Tsutsunava, G. Chichinadze, G. Beridze, L. Shumlyanskyy","doi":"10.5200/baltica.2021.2.5","DOIUrl":"https://doi.org/10.5200/baltica.2021.2.5","url":null,"abstract":"The Dizi Series is exposed within the Southern Slope zone of the Greater Caucasus, in the core of the Svaneti anticlinorium. It is mainly composed of terrigenous, volcanogenic and carbonate rocks faunistically dated from the Devonian to the Triassic inclusive. Regional and contact metamorphism of the Dizi Series rocks was studied. It is stated that the degree of regional metamorphism corresponds to the chlorite-sericite subfacies of the greenschist facies, occurring at a temperature of 300–350°C and a pressure of 1.5–2.3 kbar. As a result of the action of the Middle Jurassic intrusive rock bodies, the regionally metamorphosed rocks of the Dizi Series underwent contact metamorphism. Three zones of contact metamorphism were distinguished corresponding to albite-epidote-hornfels, andalusite-biotite-muscovite-chlorite-hornfels and andalusite-biotite-muscovite-hornfels subfacies. Contact metamorphism took place at a significantly higher temperature and lower pressure than the preceding regional metamorphism. The maximum temperature of the contact metamorphism reached ≈ 570°С, while pressure varied within the range of ≈ 0.3–0.8 kbar. The evolution of rock associations of regional and contact metamorphism of the Dizi Series was studied. The fields of facies and subfacies of regional and contact metamorphism are shown in the Ps-T diagram. Three age populations of zircons were identified using U-Pb LA-ICP-MS dating of the diorite-porphyrite intrusion in the Dizi Series: Zrn1 (ca. 2200 Ma) and Zrn2 (458 ± 29 Ma) that were captured by the diorite-porphyrite magma from the ancient magmatic and metamorphic rocks of the crystalline basement, and Zrn3 (166.5 ± 4.6 Ma) that corresponds to the age of diorite-porphyrite crystallization.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":"1 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70649361","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.2021.2.3
S. Öztürk
The main objective of this work is to make detailed region-time-magnitude analyses by describing the statistical behaviours of earthquakes in the Central Anatolian Region of Turkey. In this scope, several seismic and tectonic parameters such as Mcomp, b-value, Dc-value, Z-value, recurrence times and annual probabilities were evaluated. For the analyses, a homogeneous catalogue including 10,146 earthquakes with 1.0 ≤ Md ≤ 5.7 between 30 July 1975 and 29 December 2018 was used and spatio-temporal changes of earthquake behaviours were mapped for the beginning of 2019. Earthquake magnitudes varied from 1.9 to 3.0 on average, and hence Mcomp was considered to be 2.6. The b-value was calculated as 1.26 ± 0.07, and this relatively large value indicates that small-magnitude events are dominant. The Dc-value was computed as 1.31 ± 0.03. This small value means that distances between epicentres approach the diameter of the cluster, and seismic activity is more clustered at smaller scales or in larger regions. The spatio-temporal analyses of recurrence times suggest that the Central Anatolian Region has an intermediate/long-term earthquake hazard in comparison to occurrences of strong earthquakes in the short term. Several anomaly regions of a small b-value and a large Z-value were found in and around the Tuzgölü Fault Zone, Central Anatolian Fault Zone, Salanda fault and Niğde fault at the beginning of 2019. Thus, a combination of the regions with a lower b-value, a higher Z-value and also moderate recurrence times may give significant clues for the future possible earthquakes, and detected regions may be thought to be the most likely areas for strong/large events in the Central Anatolian Region.
{"title":"Statistical behaviours of earthquake occurrences in the Central Anatolian Region of Turkey: region-time-magnitude analyses","authors":"S. Öztürk","doi":"10.5200/baltica.2021.2.3","DOIUrl":"https://doi.org/10.5200/baltica.2021.2.3","url":null,"abstract":"The main objective of this work is to make detailed region-time-magnitude analyses by describing the statistical behaviours of earthquakes in the Central Anatolian Region of Turkey. In this scope, several seismic and tectonic parameters such as Mcomp, b-value, Dc-value, Z-value, recurrence times and annual probabilities were evaluated. For the analyses, a homogeneous catalogue including 10,146 earthquakes with 1.0 ≤ Md ≤ 5.7 between 30 July 1975 and 29 December 2018 was used and spatio-temporal changes of earthquake behaviours were mapped for the beginning of 2019. Earthquake magnitudes varied from 1.9 to 3.0 on average, and hence Mcomp was considered to be 2.6. The b-value was calculated as 1.26 ± 0.07, and this relatively large value indicates that small-magnitude events are dominant. The Dc-value was computed as 1.31 ± 0.03. This small value means that distances between epicentres approach the diameter of the cluster, and seismic activity is more clustered at smaller scales or in larger regions. The spatio-temporal analyses of recurrence times suggest that the Central Anatolian Region has an intermediate/long-term earthquake hazard in comparison to occurrences of strong earthquakes in the short term. Several anomaly regions of a small b-value and a large Z-value were found in and around the Tuzgölü Fault Zone, Central Anatolian Fault Zone, Salanda fault and Niğde fault at the beginning of 2019. Thus, a combination of the regions with a lower b-value, a higher Z-value and also moderate recurrence times may give significant clues for the future possible earthquakes, and detected regions may be thought to be the most likely areas for strong/large events in the Central Anatolian Region.","PeriodicalId":55401,"journal":{"name":"Baltica","volume":"1 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70649161","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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