Pub Date : 2023-12-01DOI: 10.52215/rev.bgs.2023.84.3.105
A. Hikov, Z. Milakovska, Valentina Lyubomirova, Nadezhda Lihareva
The distribution of main elements and REE in sequential leached phases from deep-sea polymetallic nodules and sediments from the eastern part of the Clarion-Clipperton fractures zone, NE Pacific are studied. Results show extraction of Mn in the leach 2 in both nodules and sediments. The extraction of Fe, P and REE is different for leach 2, 3 and residual fraction for nodules and sediments. Phosphorous and REE have strong positive correlation which suggests that the phosphate component is the main important carrier of REE in both nodules and sediments but Fe-Mn oxyhydroxides and clay minerals cannot be excluded as carriers of REE.
{"title":"REE distribution in sequential leached phases from deep-sea polymetallic nodules and sediments","authors":"A. Hikov, Z. Milakovska, Valentina Lyubomirova, Nadezhda Lihareva","doi":"10.52215/rev.bgs.2023.84.3.105","DOIUrl":"https://doi.org/10.52215/rev.bgs.2023.84.3.105","url":null,"abstract":"The distribution of main elements and REE in sequential leached phases from deep-sea polymetallic nodules and sediments from the eastern part of the Clarion-Clipperton fractures zone, NE Pacific are studied. Results show extraction of Mn in the leach 2 in both nodules and sediments. The extraction of Fe, P and REE is different for leach 2, 3 and residual fraction for nodules and sediments. Phosphorous and REE have strong positive correlation which suggests that the phosphate component is the main important carrier of REE in both nodules and sediments but Fe-Mn oxyhydroxides and clay minerals cannot be excluded as carriers of REE.","PeriodicalId":509487,"journal":{"name":"Review of the Bulgarian Geological Society","volume":"48 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139192606","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}
Pub Date : 2023-12-01DOI: 10.52215/rev.bgs.2023.84.3.165
I. Boncheva, P. Andreeva, V. Sachanski
Five conodont zones (falsiovalis, rhenana, triangularis, marginifera, and praesulcata) were recognized within the Upper Devonian carbonate sequence in the Preslavtsi 2 well from the Moesian Terrane in NE Bulgaria. Microfacies study indicates a climate change (from the Subtropical Arid to the Warm Temperate Climatic Zones) recorded in the Frasnian–Famennian succession. Thus, during the Givetian and early Frasnian, sedimentation took place in an arid tidal flat setting, where microbial mats and lagoon carbonates have been formed. In the late Frasnian, a transgression, followed by a rapid regression was recorded that are presumably related to the Late Devonian Kellwasser event. At the beginning of the Famennian, a climate change has occurred and various shallow- and open-marine carbonates have been formed under warm temperate climate conditions.
{"title":"Conodont biostratigraphy, carbonate microfacies and climate changes during the Late Devonain (Frasnian–Famennian) in the Preslavtsi 2 well (Moesian Terrane, NE Bulgaria)","authors":"I. Boncheva, P. Andreeva, V. Sachanski","doi":"10.52215/rev.bgs.2023.84.3.165","DOIUrl":"https://doi.org/10.52215/rev.bgs.2023.84.3.165","url":null,"abstract":"Five conodont zones (falsiovalis, rhenana, triangularis, marginifera, and praesulcata) were recognized within the Upper Devonian carbonate sequence in the Preslavtsi 2 well from the Moesian Terrane in NE Bulgaria. Microfacies study indicates a climate change (from the Subtropical Arid to the Warm Temperate Climatic Zones) recorded in the Frasnian–Famennian succession. Thus, during the Givetian and early Frasnian, sedimentation took place in an arid tidal flat setting, where microbial mats and lagoon carbonates have been formed. In the late Frasnian, a transgression, followed by a rapid regression was recorded that are presumably related to the Late Devonian Kellwasser event. At the beginning of the Famennian, a climate change has occurred and various shallow- and open-marine carbonates have been formed under warm temperate climate conditions.","PeriodicalId":509487,"journal":{"name":"Review of the Bulgarian Geological Society","volume":"34 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139193777","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 article examines the values of the vertical temperature gradient along the northern slope of the Western Rhodopes Мountain. The average monthly temperatures in three stations located between 290 and 1535 m a.s.l. were used as the basis of the calculations. Calculations were made for the following temperature indicators: monthly average, average minimum and average maximum, and absolute minimum and absolute maximum. The study covers the period July 2022 – August 2023. The values of the vertical temperature gradient are greatest in the summer and smallest in the autumn-winter period. In the lower part of the studied territory, in winter the gradient also has negative values, due to temperature inversions, and in summer its values are three times greater than in the upper part, due to the greater turbulence of the atmosphere.
{"title":"Temperature gradient along the northern slope of the Western Rhodopes","authors":"Simeon Matev, Petko Bojkov, Dimitar Krenchev, Nina Nikolova","doi":"10.52215/rev.bgs.2023.84.3.249","DOIUrl":"https://doi.org/10.52215/rev.bgs.2023.84.3.249","url":null,"abstract":"The article examines the values of the vertical temperature gradient along the northern slope of the Western Rhodopes Мountain. The average monthly temperatures in three stations located between 290 and 1535 m a.s.l. were used as the basis of the calculations. Calculations were made for the following temperature indicators: monthly average, average minimum and average maximum, and absolute minimum and absolute maximum. The study covers the period July 2022 – August 2023. The values of the vertical temperature gradient are greatest in the summer and smallest in the autumn-winter period. In the lower part of the studied territory, in winter the gradient also has negative values, due to temperature inversions, and in summer its values are three times greater than in the upper part, due to the greater turbulence of the atmosphere.","PeriodicalId":509487,"journal":{"name":"Review of the Bulgarian Geological Society","volume":"20 42","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139193851","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}
Pub Date : 2023-12-01DOI: 10.52215/rev.bgs.2023.84.3.89
Stoyan Georgiev, Eleonora Balkanska, Stefan Velev, Stefan Metodiev, Neven Georgiev, M. Guillong, Sergiy Kurylo
Three samples from the main phase of the Barnard Point Batholith of granodiorite from the sea level up to 463 m of Mac Kay Peak – are analyzed. The U-Pb zircon geochronology reveals magmatic crystallization at 43.89±032 Ma. The Ca-amphibole thermobarometry shows a shallow crustal level emplacement (5–3.5 km and temperatures of 810–750 °C). Two main episodes that correspond to the uplift of the Tangra Mountain and exhumation of the batholith are distinguished using apatite fission-track analysis. The models reveal initial very rapid cooling to ~ 80–90 °C between 40 and 33 Ma and a second episode of uplift and moderate cooling to surface temperatures between 22 and 15 Ma. The obtained positive age-altitude correlation suggests moderate exhumation rate of 340 m/Ma. The thermal modelling of the hypsometrically lowest sample reveals a later moderate cooling event to surface temperatures from 8 Ma to recent times, which corresponds to the Bransfield Rift initiation.
分析了从海平面到 Mac Kay Peak 463 米处花岗闪长岩巴纳德角岩体主岩阶段的三个样本。U-Pb锆石地质年代显示岩浆结晶时间为43.89±032Ma。钙闪石测温显示了地壳浅层的形成(5-3.5 千米,温度为 810-750 °C)。利用磷灰石裂变轨迹分析,可区分与唐格拉山隆起和浴成岩掘出相对应的两个主要阶段。这些模型显示,在 40 至 33 Ma 之间,最初的冷却速度非常快,达到 ~ 80-90 °C;在 22 至 15 Ma 之间,发生了第二次隆起和适度冷却,达到地表温度。得到的年龄-高度正相关表明,中度隆升速率为340 m/Ma。对湿度最低的样本进行的热模拟显示,从 8 Ma 到最近,地表温度出现了一次中等程度的冷却,这与布兰斯菲尔德大裂谷的起始时间相吻合。
{"title":"From pluton intrusion to its exhumation: a case study from Barnard Point Batholith, Livingston Island, South Shetland Archipelago, Antarctica","authors":"Stoyan Georgiev, Eleonora Balkanska, Stefan Velev, Stefan Metodiev, Neven Georgiev, M. Guillong, Sergiy Kurylo","doi":"10.52215/rev.bgs.2023.84.3.89","DOIUrl":"https://doi.org/10.52215/rev.bgs.2023.84.3.89","url":null,"abstract":"Three samples from the main phase of the Barnard Point Batholith of granodiorite from the sea level up to 463 m of Mac Kay Peak – are analyzed. The U-Pb zircon geochronology reveals magmatic crystallization at 43.89±032 Ma. The Ca-amphibole thermobarometry shows a shallow crustal level emplacement (5–3.5 km and temperatures of 810–750 °C). Two main episodes that correspond to the uplift of the Tangra Mountain and exhumation of the batholith are distinguished using apatite fission-track analysis. The models reveal initial very rapid cooling to ~ 80–90 °C between 40 and 33 Ma and a second episode of uplift and moderate cooling to surface temperatures between 22 and 15 Ma. The obtained positive age-altitude correlation suggests moderate exhumation rate of 340 m/Ma. The thermal modelling of the hypsometrically lowest sample reveals a later moderate cooling event to surface temperatures from 8 Ma to recent times, which corresponds to the Bransfield Rift initiation.","PeriodicalId":509487,"journal":{"name":"Review of the Bulgarian Geological Society","volume":"108 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139194350","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}
Pub Date : 2023-12-01DOI: 10.52215/rev.bgs.2023.84.3.43
Larisa Nesheva, Denka Yanakieva, P. Petrov, Stela Atanasova-Vladimirova, Nadia Petrova, R. Vassileva, Ivanina Sergeeva, Z. Cherkezova-Zheleva, Daniela Paneva
Planerite, aheylite and faustite are minerals of the turquoise group. They were found in samples from the Chala deposit, Spahievo Ore Field. The samples consist of a small crystalline mass of the investigated mineral phases among quartz. Single spherulites up to 2 mm in size and aggregates of spherulites with a yellowish-greenish color are observed in small cavities. Transparent, colorless wavellite crystals and aggregates are crystallized on spherulites. For the first time in Bulgaria, the presence of aheylite was established.
{"title":"Planerite with aheylite and faustite from the Chala deposit, Spahievo Ore Field","authors":"Larisa Nesheva, Denka Yanakieva, P. Petrov, Stela Atanasova-Vladimirova, Nadia Petrova, R. Vassileva, Ivanina Sergeeva, Z. Cherkezova-Zheleva, Daniela Paneva","doi":"10.52215/rev.bgs.2023.84.3.43","DOIUrl":"https://doi.org/10.52215/rev.bgs.2023.84.3.43","url":null,"abstract":"Planerite, aheylite and faustite are minerals of the turquoise group. They were found in samples from the Chala deposit, Spahievo Ore Field. The samples consist of a small crystalline mass of the investigated mineral phases among quartz. Single spherulites up to 2 mm in size and aggregates of spherulites with a yellowish-greenish color are observed in small cavities. Transparent, colorless wavellite crystals and aggregates are crystallized on spherulites. For the first time in Bulgaria, the presence of aheylite was established.","PeriodicalId":509487,"journal":{"name":"Review of the Bulgarian Geological Society","volume":"19 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139194402","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}
Pub Date : 2023-12-01DOI: 10.52215/rev.bgs.2023.84.3.141
Alexander Vlahov, Rositsa Ivanova
Two X-ray diffraction methods were chosen to determine the degree of structural order (degree of graphitization) of natural carbonaceous matter. Factors influencing the graphitization processes during the progressive and regressive stages of metamorphism are examined. The correlation of the degrees of structural order of the carbonaceous material with the sequence of mineral growth allows the metamorphic history of the graphite-bearing rocks to be traced. The obtained data can be used for the evaluation of graphite as a raw material.
选择了两种 X 射线衍射方法来确定天然碳质物质的结构有序程度(石墨化程度)。研究了在变质的进展和退步阶段影响石墨化过程的因素。将碳质物质的结构顺序与矿物生长顺序联系起来,可以追溯含石墨岩石的变质历史。获得的数据可用于评估石墨作为原材料的价值。
{"title":"Different graphitization degrees of carbon matter in rocks of a same metamorphic evolution","authors":"Alexander Vlahov, Rositsa Ivanova","doi":"10.52215/rev.bgs.2023.84.3.141","DOIUrl":"https://doi.org/10.52215/rev.bgs.2023.84.3.141","url":null,"abstract":"Two X-ray diffraction methods were chosen to determine the degree of structural order (degree of graphitization) of natural carbonaceous matter. Factors influencing the graphitization processes during the progressive and regressive stages of metamorphism are examined. The correlation of the degrees of structural order of the carbonaceous material with the sequence of mineral growth allows the metamorphic history of the graphite-bearing rocks to be traced. The obtained data can be used for the evaluation of graphite as a raw material.","PeriodicalId":509487,"journal":{"name":"Review of the Bulgarian Geological Society","volume":"305 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139195473","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}
Pub Date : 2023-12-01DOI: 10.52215/rev.bgs.2023.84.3.295
Jovana Mladenović, Vesna Ristić Vakanjac, M. Kresojević, B. Vakanjac, Jugoslav Nikolić, D. Polomcic, Dragoljub Bajić
The Velika Morava River originates at the junction of the Južna Morava and Zapadna Morava at the town of Stalać in Serbia. It is 185 km long and empties into the Danube. The Velika Morava River Basin occupies a land area of 37 444 km2. The river flows through central Serbia, which features the most fertile land and the highest population density in the country. Public water supply in this region of Serbia relies on groundwater formed in alluvial sediments of the Velika Morava. Both industry and agriculture are well developed. There is intensive sand and gravel mining along the riverbanks, which has deepened the river channel by as much as 4 m and lowered water surface elevations at Ljubičevski Most. Given that, there is a hydraulic connection between groundwater and the Velika Morava, water levels in wells have also declined. The paper analyzes the elevations of the Velika Morava’s water surface and the water table.
{"title":"Anthropogenic impact on the groundwater regime: Case study of the Velika Morava alluvium","authors":"Jovana Mladenović, Vesna Ristić Vakanjac, M. Kresojević, B. Vakanjac, Jugoslav Nikolić, D. Polomcic, Dragoljub Bajić","doi":"10.52215/rev.bgs.2023.84.3.295","DOIUrl":"https://doi.org/10.52215/rev.bgs.2023.84.3.295","url":null,"abstract":"The Velika Morava River originates at the junction of the Južna Morava and Zapadna Morava at the town of Stalać in Serbia. It is 185 km long and empties into the Danube. The Velika Morava River Basin occupies a land area of 37 444 km2. The river flows through central Serbia, which features the most fertile land and the highest population density in the country. Public water supply in this region of Serbia relies on groundwater formed in alluvial sediments of the Velika Morava. Both industry and agriculture are well developed. There is intensive sand and gravel mining along the riverbanks, which has deepened the river channel by as much as 4 m and lowered water surface elevations at Ljubičevski Most. Given that, there is a hydraulic connection between groundwater and the Velika Morava, water levels in wells have also declined. The paper analyzes the elevations of the Velika Morava’s water surface and the water table.","PeriodicalId":509487,"journal":{"name":"Review of the Bulgarian Geological Society","volume":"56 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139195941","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}
Pub Date : 2023-12-01DOI: 10.52215/rev.bgs.2023.84.3.39
Yana Georgieva, R. Vassileva, Sylvina Georgieva
The major and trace-element chemistry of two pyrite generations (Py1 and Py2) from the Kandilka epithermal prospect was studied by EDS-scanning electron microscopy and laser ablation ICP-MS techniques. Both generations of pyrite are distinguished by occurrence and chemical properties. Pyrite from the first generation (Py1) is established as trace-element poor, sub- to euhedral (mainly single) crystals up to 200 µm. The later As-bearing pyrite (Py2) forms fine-grained semi-massive aggregates with increased contents of trace-elements. Except for arsenic, Py2 is enriched in gold and antimony. The As content of Py2 increases in an oscillatory manner from core to rim, reflecting changes in As activity and the chemical evolution of ore-bearing fluids. The oscillatory-zoned pyrite is composed of complex rhythmic overgrowths of alternating As-rich and As-poor bands. Positive correlation between As- and Au-content in Py2 is characteristic. According to the current results, the Kandilka prospect could be concerned as a low-sulphidation deposit.
{"title":"Incorporation of As, Sb and Tl in pyrite from the epithermal Kandilka prospect, Eastern Rhodopes, south Bulgaria","authors":"Yana Georgieva, R. Vassileva, Sylvina Georgieva","doi":"10.52215/rev.bgs.2023.84.3.39","DOIUrl":"https://doi.org/10.52215/rev.bgs.2023.84.3.39","url":null,"abstract":"The major and trace-element chemistry of two pyrite generations (Py1 and Py2) from the Kandilka epithermal prospect was studied by EDS-scanning electron microscopy and laser ablation ICP-MS techniques. Both generations of pyrite are distinguished by occurrence and chemical properties. Pyrite from the first generation (Py1) is established as trace-element poor, sub- to euhedral (mainly single) crystals up to 200 µm. The later As-bearing pyrite (Py2) forms fine-grained semi-massive aggregates with increased contents of trace-elements. Except for arsenic, Py2 is enriched in gold and antimony. The As content of Py2 increases in an oscillatory manner from core to rim, reflecting changes in As activity and the chemical evolution of ore-bearing fluids. The oscillatory-zoned pyrite is composed of complex rhythmic overgrowths of alternating As-rich and As-poor bands. Positive correlation between As- and Au-content in Py2 is characteristic. According to the current results, the Kandilka prospect could be concerned as a low-sulphidation deposit.","PeriodicalId":509487,"journal":{"name":"Review of the Bulgarian Geological Society","volume":"108 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139196011","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}
Pub Date : 2023-12-01DOI: 10.52215/rev.bgs.2023.84.3.67
P. Petrov
Millerite is discovered in samples from Krushev Dol and Mogilata deposits in the Madan ore field. It was found in two associations different in appearance and mineral composition. One of them is with light green ferrodolomite, and the other with bright green mariposite (chromium-bearing phengite). Only cobalt and iron are detected as impurity elements in some analyses. They are in small concentrations (below 0.01 apfu). The Ni/S ratio is 0.95. The nickel source is associated with bodies of serpentinized ultramafics cut by ore-bearing veins.
{"title":"Millerite from the Madan ore field","authors":"P. Petrov","doi":"10.52215/rev.bgs.2023.84.3.67","DOIUrl":"https://doi.org/10.52215/rev.bgs.2023.84.3.67","url":null,"abstract":"Millerite is discovered in samples from Krushev Dol and Mogilata deposits in the Madan ore field. It was found in two associations different in appearance and mineral composition. One of them is with light green ferrodolomite, and the other with bright green mariposite (chromium-bearing phengite). Only cobalt and iron are detected as impurity elements in some analyses. They are in small concentrations (below 0.01 apfu). The Ni/S ratio is 0.95. The nickel source is associated with bodies of serpentinized ultramafics cut by ore-bearing veins.","PeriodicalId":509487,"journal":{"name":"Review of the Bulgarian Geological Society","volume":"42 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139191351","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}
Pub Date : 2023-12-01DOI: 10.52215/rev.bgs.2023.84.3.101
V. Grozdev, R. Vassileva, Sylvina Georgieva
Ages of pegmatites from two localities (Rakitovo, Lepenitsa) from the western Rhodope Mts. were acquired by U-Pb geochronology on zircon with LA-ICP-MS. The pegmatites are hosted by the metamorphic rocks of the Chepino lithotectonic unit. The large pegmatite/s accumulation from the “Suhata Reka” quarry (Rakitovo locality) is formed at 68.7±1.3 Ma, while small deformed body southwards of Velingrad town (Lepenitsa locality) yielded age of 63.4±1.2 Ma. Crosscutting altered andesite dyke is presumed to intrude the metamorphic rocks and pegmatite at 59 Ma in the Lepenitsa locality. The data suggests connection with the initial stage of the magmatic activity of the Rila-West-Rhodope Batholith (RWRB).
{"title":"Pegmatites from western Rhodope Mts.: zircon data","authors":"V. Grozdev, R. Vassileva, Sylvina Georgieva","doi":"10.52215/rev.bgs.2023.84.3.101","DOIUrl":"https://doi.org/10.52215/rev.bgs.2023.84.3.101","url":null,"abstract":"Ages of pegmatites from two localities (Rakitovo, Lepenitsa) from the western Rhodope Mts. were acquired by U-Pb geochronology on zircon with LA-ICP-MS. The pegmatites are hosted by the metamorphic rocks of the Chepino lithotectonic unit. The large pegmatite/s accumulation from the “Suhata Reka” quarry (Rakitovo locality) is formed at 68.7±1.3 Ma, while small deformed body southwards of Velingrad town (Lepenitsa locality) yielded age of 63.4±1.2 Ma. Crosscutting altered andesite dyke is presumed to intrude the metamorphic rocks and pegmatite at 59 Ma in the Lepenitsa locality. The data suggests connection with the initial stage of the magmatic activity of the Rila-West-Rhodope Batholith (RWRB).","PeriodicalId":509487,"journal":{"name":"Review of the Bulgarian Geological Society","volume":"64 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139192571","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}