Omar Saidi, Hicham Si Mhamdi, Abdelhafid Essalhi, Abdeslam Toummite
Jbel Tijekht is one of the most important geological structures of the Ougnat-Ouzina ridge in the Eastern Anti-Atlas. This crescent-shaped massif was affected by a network fractures that is visible at different scales. It is particularly rich in numerous mineralized veins of barite, and is associated with other minerals (e.g. pyrite, chalcopyrite, sphalerite and galena). In order to study fracture systems in the mining zone of Jbel Tijekht, we opted for a combination of remote sensing and field investigation that became an important tool for fracture mapping and mineral exploration. This work presents a methodological approach to detect structural lineaments. For this purpose, various techniques were applied to the Landsat 8 image to improve the visibility of linear structures. After the radiometric and atmospheric corrections, the colors composites and directional filters applied to the Principal component (PC1) allow for the establishment of a lineaments map of Jbel Tijekht. The validation and the correction of lineaments are based on preexisting documents combined with field observations. Statistical analysis of the lineament map allows for identification of at least three directional fracture systems with average NS, NE-SW, and ENE-WSW orientations. NS and NE-SW systems show a high density in the largest part of the study area. These results clearly overlap different tectonic structures and existing veins. It allowed for the establishment of a geological link between lithology, fractures systems and mineralization. The fracture density can be attributed to the last variscan brittle phases, reflecting the rheology of rock units; the high fracture density is observed in competent rocks such as the Tabanit sandstones. These zones constitute a favorable area for mineralization deposits.
{"title":"Mapeo de redes de fracturas mediante imágenes Landsat-8 OLI en la zona minera de Jbel Tijekht en el Anti-Atlas oriental de Marruecos","authors":"Omar Saidi, Hicham Si Mhamdi, Abdelhafid Essalhi, Abdeslam Toummite","doi":"10.3989/egeol.43887.587","DOIUrl":"https://doi.org/10.3989/egeol.43887.587","url":null,"abstract":"Jbel Tijekht is one of the most important geological structures of the Ougnat-Ouzina ridge in the Eastern Anti-Atlas. This crescent-shaped massif was affected by a network fractures that is visible at different scales. It is particularly rich in numerous mineralized veins of barite, and is associated with other minerals (e.g. pyrite, chalcopyrite, sphalerite and galena). In order to study fracture systems in the mining zone of Jbel Tijekht, we opted for a combination of remote sensing and field investigation that became an important tool for fracture mapping and mineral exploration. This work presents a methodological approach to detect structural lineaments. For this purpose, various techniques were applied to the Landsat 8 image to improve the visibility of linear structures. After the radiometric and atmospheric corrections, the colors composites and directional filters applied to the Principal component (PC1) allow for the establishment of a lineaments map of Jbel Tijekht. The validation and the correction of lineaments are based on preexisting documents combined with field observations. Statistical analysis of the lineament map allows for identification of at least three directional fracture systems with average NS, NE-SW, and ENE-WSW orientations. NS and NE-SW systems show a high density in the largest part of the study area. These results clearly overlap different tectonic structures and existing veins. It allowed for the establishment of a geological link between lithology, fractures systems and mineralization. The fracture density can be attributed to the last variscan brittle phases, reflecting the rheology of rock units; the high fracture density is observed in competent rocks such as the Tabanit sandstones. These zones constitute a favorable area for mineralization deposits.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"27 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2020-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78333737","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}
H. Astibia, J. C. Corral, Germán Álvarez-Pérez, Miguel Ángel López Horgue, Aitor Payros
During Eocene times the Pyrenean area may have played an important role as a paleobiogeographic link between the Western Tethys and the North Atlantic domains. However, its marine faunas are still poorly documented. This paper presents the results of a first study on the mid–upper Eocene (Lutetian to Priabonian) marine macrofossils of Navarre included in the paleontological collection of Maximo Ruiz de Gaona, a researcher whose studies on the geology and paleontology of this territory constitute an obligatory historical reference. The described fossils come from the Eocene marly formations of the Pamplona basin and the Urbasa-Andia limestone Formation and overlying deposits, in the Estella-Urbasa area, west of the Pamplona fault. Some of the specimens studied come from outcrops that do not exist any longer. This fact increases the interest of conservation and the study of this collection. The paleontological data from the Estella-Urbasa area are almost entirely new. This study has allowed the description of 24 taxa of marine macrofauna. Seven of them ─Cyclolitopsis patera, Funginellastraea barcelonensis, Pycnodonte rarilamella, Metacrinus sp., Triplacidia sp., in addition to an indeterminate Cyclostomatida bryozoan and an indeterminate Serpulidae annelid─ are new to the fossil record of Navarre. The macropaleontological associations described in this and previous works are not as diverse as those from other coeval European geological regions. In addition to possible ecological conditions, sampling biases and, above all, taphonomic biases, specifically the loss of invertebrate species with aragonite skeletons, arise as the main explanation.
在始新世时期，比利牛斯地区可能作为连接西特提斯和北大西洋域的古生物地理纽带发挥了重要作用。然而，它的海洋动物仍然很少有记录。本文介绍了对纳瓦拉地区始新世中上(Lutetian至Priabonian)海洋宏观化石的首次研究结果，这些化石被纳入了Maximo Ruiz de Gaona的古生物收藏中，他对这一地区的地质和古生物学研究构成了强制性的历史参考。所描述的化石来自潘普洛纳盆地始新世灰岩地层和Urbasa-Andia灰岩地层及其上覆沉积物，位于潘普洛纳断层以西的Estella-Urbasa地区。一些被研究的标本来自于已不复存在的露头岩层。这一事实增加了保护和研究这些藏品的兴趣。来自埃斯特拉-乌尔巴萨地区的古生物学数据几乎是全新的。本研究对海洋大型动物24个分类群进行了描述。其中7种是纳瓦拉化石记录中的新发现物种，包括:patera Cyclolitopsis、barcelonensis Funginellastraea、Pycnodonte rarilamella、Metacrinus sp.、Triplacidia sp.，以及一种不确定的Cyclostomatida苔藓虫和一种不确定的Serpulidae annelid。在本研究和以前的研究中所描述的宏观古生物学关联并不像其他同时期欧洲地质区域那样多样化。除了可能的生态条件外，抽样偏差，尤其是地语学偏差，特别是文石骨架的无脊椎动物物种的消失，是主要的解释。
{"title":"Nuevos datos sobre las faunas marinas del Eoceno medio-superior de Navarra (área surpirenaica occidental). Revisión de los fósiles de la colección Ruiz de Gaona","authors":"H. Astibia, J. C. Corral, Germán Álvarez-Pérez, Miguel Ángel López Horgue, Aitor Payros","doi":"10.3989/egeol.43621.545","DOIUrl":"https://doi.org/10.3989/egeol.43621.545","url":null,"abstract":"During Eocene times the Pyrenean area may have played an important role as a paleobiogeographic link between the Western Tethys and the North Atlantic domains. However, its marine faunas are still poorly documented. This paper presents the results of a first study on the mid–upper Eocene (Lutetian to Priabonian) marine macrofossils of Navarre included in the paleontological collection of Maximo Ruiz de Gaona, a researcher whose studies on the geology and paleontology of this territory constitute an obligatory historical reference. The described fossils come from the Eocene marly formations of the Pamplona basin and the Urbasa-Andia limestone Formation and overlying deposits, in the Estella-Urbasa area, west of the Pamplona fault. Some of the specimens studied come from outcrops that do not exist any longer. This fact increases the interest of conservation and the study of this collection. The paleontological data from the Estella-Urbasa area are almost entirely new. This study has allowed the description of 24 taxa of marine macrofauna. Seven of them ─Cyclolitopsis patera, Funginellastraea barcelonensis, Pycnodonte rarilamella, Metacrinus sp., Triplacidia sp., in addition to an indeterminate Cyclostomatida bryozoan and an indeterminate Serpulidae annelid─ are new to the fossil record of Navarre. The macropaleontological associations described in this and previous works are not as diverse as those from other coeval European geological regions. In addition to possible ecological conditions, sampling biases and, above all, taphonomic biases, specifically the loss of invertebrate species with aragonite skeletons, arise as the main explanation.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"129 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2020-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87421714","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}
La contaminación por nitratos de fuentes difusas es una de las principales causas del deterioro de la calidad de los recursos hídricos subterráneos a escala global. Recientes investigaciones señalan la necesidad de minimizar la incertidumbre en la evaluación de la vulnerabilidad de las aguas subterráneas, mediante el desarrollo de metodologías robustas que permitan evaluar la vulnerabilidad bajo un enfoque fuente–vía–receptor en el contexto de la cuenca hidrológica. El procedimiento LU–IV (Arauzo, 2017) fue ideado para cartografiar la vulnerabilidad intrínseca de las aguas subterráneas (riesgos asociados al medio físico) y la vulnerabilidad específica a la contaminación por nitrato (riesgos asociados a los usos del suelo en territorios intrínsecamente vulnerables), con el objetivo final de mejorar la delimitación de las zonas vulnerables a la contaminación por nitrato (ZVN). Esta metodología utiliza parámetros sencillos y fácilmente disponibles que, combinados en un entorno de SIG, permite evaluar con precisión la vulnerabilidad (intrínseca y específica) en la totalidad de la cuenca de drenaje (área susceptible de drenar agua, potencialmente contaminada por nitrato, hacia un acuífero receptor). La aplicación del procedimiento LU–IV a la cuenca hidrológica del río Ebro (N.E. de España) ha permitido determinar que una superficie de 18.757 km2 presenta un grado de vulnerabilidad específica a la contaminación por nitrato de alto a extremo, por lo que los territorios afectados podrían ser potencialmente designables como ZVN. Esta superficie difiere de los 9.796 km2 designados oficialmente como ZVN por las administraciones autonómicas con competencias para la designación de ZVN en la cuenca del Ebro. Si bien los territorios oficialmente designados coinciden en gran medida con los resultados de esta investigación, la aplicación del nuevo procedimiento ha permitido identificar un 50% más de territorios clasificables como zonas vulnerables. Las áreas aluviales presentaron el mayor grado de vulnerabilidad (tanto intrínseca como específica) afectando a la mayor parte de su territorio, lo que sugiere la necesidad de plantear una protección integral de todas las superficies aluviales, no sólo en la cuenca del Ebro, sino a escala nacional y europea.
{"title":"Cartografía de la vulnerabilidad de las aguas subterráneas a la contaminación por nitratos de fuentes difusas en la cuenca del río Ebro (N.E. de España)","authors":"M. Arauzo, M. Valladolid, G. García","doi":"10.3989/EGEOL.43868.586","DOIUrl":"https://doi.org/10.3989/EGEOL.43868.586","url":null,"abstract":"La contaminación por nitratos de fuentes difusas es una de las principales causas del deterioro de la calidad de los recursos hídricos subterráneos a escala global. Recientes investigaciones señalan la necesidad de minimizar la incertidumbre en la evaluación de la vulnerabilidad de las aguas subterráneas, mediante el desarrollo de metodologías robustas que permitan evaluar la vulnerabilidad bajo un enfoque fuente–vía–receptor en el contexto de la cuenca hidrológica. El procedimiento LU–IV (Arauzo, 2017) fue ideado para cartografiar la vulnerabilidad intrínseca de las aguas subterráneas (riesgos asociados al medio físico) y la vulnerabilidad específica a la contaminación por nitrato (riesgos asociados a los usos del suelo en territorios intrínsecamente vulnerables), con el objetivo final de mejorar la delimitación de las zonas vulnerables a la contaminación por nitrato (ZVN). Esta metodología utiliza parámetros sencillos y fácilmente disponibles que, combinados en un entorno de SIG, permite evaluar con precisión la vulnerabilidad (intrínseca y específica) en la totalidad de la cuenca de drenaje (área susceptible de drenar agua, potencialmente contaminada por nitrato, hacia un acuífero receptor). \u0000La aplicación del procedimiento LU–IV a la cuenca hidrológica del río Ebro (N.E. de España) ha permitido determinar que una superficie de 18.757 km2 presenta un grado de vulnerabilidad específica a la contaminación por nitrato de alto a extremo, por lo que los territorios afectados podrían ser potencialmente designables como ZVN. Esta superficie difiere de los 9.796 km2 designados oficialmente como ZVN por las administraciones autonómicas con competencias para la designación de ZVN en la cuenca del Ebro. Si bien los territorios oficialmente designados coinciden en gran medida con los resultados de esta investigación, la aplicación del nuevo procedimiento ha permitido identificar un 50% más de territorios clasificables como zonas vulnerables. Las áreas aluviales presentaron el mayor grado de vulnerabilidad (tanto intrínseca como específica) afectando a la mayor parte de su territorio, lo que sugiere la necesidad de plantear una protección integral de todas las superficies aluviales, no sólo en la cuenca del Ebro, sino a escala nacional y europea.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"42 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2020-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82682683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. Guerra, Cristina Veiga-Pires, M. L. González-Regalado, M. Abad, Antonio Toscano, J. Muñoz, F. Ruiz, Joaquín Rodríguez Vidal, L. M. Cáceres, Tatiana Izquierdo, M. I. Carretero, M. Pozo, Guadalupe Monge, J. Tosquella, Paula Gómez, Verónica Romero, Marta Arroyo, Gabrlel Gómez
During the Roman period (3rd century BC-5th century AD), the areas located near the present-day mouth of the Guadalquivir River were occupied by a lagoon with marine connection, according to the paleoenvironmental interpretation of benthic foraminiferal assemblages obtained in a core extracted in the Donana National Park. The inner zones of this lagoon were occupied by clayey tidal flats, which suffered the effects of a storm towards the end of the 1st century A.D. The comparison with the ostracod assemblages of the same core confirms this reconstruction and the paleogeographic data provided by various chroniclers, although these microcrustaceans better record the paleoenvironmental changes in these coastal sectors.
{"title":"El contraste micropaleontológico de la Historia: el Lacus Ligustinus romano","authors":"L. Guerra, Cristina Veiga-Pires, M. L. González-Regalado, M. Abad, Antonio Toscano, J. Muñoz, F. Ruiz, Joaquín Rodríguez Vidal, L. M. Cáceres, Tatiana Izquierdo, M. I. Carretero, M. Pozo, Guadalupe Monge, J. Tosquella, Paula Gómez, Verónica Romero, Marta Arroyo, Gabrlel Gómez","doi":"10.3989/EGEOL.43851.585","DOIUrl":"https://doi.org/10.3989/EGEOL.43851.585","url":null,"abstract":"During the Roman period (3rd century BC-5th century AD), the areas located near the present-day mouth of the Guadalquivir River were occupied by a lagoon with marine connection, according to the paleoenvironmental interpretation of benthic foraminiferal assemblages obtained in a core extracted in the Donana National Park. The inner zones of this lagoon were occupied by clayey tidal flats, which suffered the effects of a storm towards the end of the 1st century A.D. The comparison with the ostracod assemblages of the same core confirms this reconstruction and the paleogeographic data provided by various chroniclers, although these microcrustaceans better record the paleoenvironmental changes in these coastal sectors.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"23 1","pages":"131"},"PeriodicalIF":0.7,"publicationDate":"2020-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75175474","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}
T. Kotsakis, L. Pandolfi, L. Maiorino, C. Petronio, G. Sansalone, L. Salari
The fossiliferous deposit (karst cavity) in La Grave, a locality near the small town of Avetrana (Taranto, southern Italy), has yielded numerous fossils of vertebrates. The remains of large mammals have been the subject of several studies. This paper examines the remains of small vertebrates and identifies four taxa of amphibians ( Bufo bufo, Bufotes gr. B. viridis, Hyla gr. H. Arborea and Rana (s.l.) sp.), four taxa of reptiles ( Testudo hermanni, Podarcis sp., Zamenis gr. Z. longissimus, Natrix natrix ), and nine taxa of small mammals ( Erinaceus europaeus, Crocidura suaveolens, Arvicola italicus, Microtus (Terricola) savii, Microtus (Microtus) arvalis, Apodemus gr. A. sylvaticus - A. flavicollis, Hystrix (Acanthion) vinogradovi, Oryctolagus cuniculus and Lepus corsicanus ). From a biochronological point of view, the data on small and large vertebrates indicate an age between the beginning of the Late Pleistocene (MIS 5e) and the central part of MIS 3. The most recent fossiliferous layer (bed 8) is likely to have been deposited during a cooler period when compared to the previous layers.The data from small fossil vertebrates combined with those emerging from the large mammals and birds evidence the presence, near the karstic cavity, of open spaces (prairies) with pools of water, bordered by wooded areas and, not far, the presence of a rocky coastline.
拉格雷夫(La Grave)的化石矿床(喀斯特洞穴)位于意大利南部塔兰托(Taranto)小镇avetraa附近，已经发现了许多脊椎动物的化石。大型哺乳动物的遗骸一直是几项研究的主题。本文通过对小型脊椎动物遗骸的研究，鉴定出两栖动物4个分类群(Bufo Bufo, Bufotes gr. b.v irridis, Hyla gr. H. Arborea和Rana (s.l.) sp.)，爬行动物4个分类群(Testudo hermanni, Podarcis sp.， Zamenis gr. Z. longissimus, Natrix Natrix)，小型哺乳动物9个分类群(Erinaceus europaeus, Crocidura suaveolens, Arvicola italicus, Microtus (Terricola) savii, Microtus (Microtus) arvalis, Apodemus gr. A. sylvaticus - A. flavicollis，棘毛猴、小黄猴、小黄猴。从生物年代学的角度来看，小型和大型脊椎动物的数据表明其年龄介于晚更新世(MIS 5e)开始和MIS 3的中心部分之间。与前几层相比，最近的化石层(8层)可能是在较冷的时期沉积的。从小型脊椎动物化石和从大型哺乳动物和鸟类化石中得到的数据表明，在喀斯特洞穴附近，存在着带有水池的开放空间(草原)，周围是树木繁茂的地区，不远的地方还有岩石海岸线。
{"title":"Pequeños vertebrados del relleno kárstico del Pleistoceno Superior de Avetrana (Apulia, Sur de Italia)","authors":"T. Kotsakis, L. Pandolfi, L. Maiorino, C. Petronio, G. Sansalone, L. Salari","doi":"10.3989/egeol.43378.508","DOIUrl":"https://doi.org/10.3989/egeol.43378.508","url":null,"abstract":"The fossiliferous deposit (karst cavity) in La Grave, a locality near the small town of Avetrana (Taranto, southern Italy), has yielded numerous fossils of vertebrates. The remains of large mammals have been the subject of several studies. This paper examines the remains of small vertebrates and identifies four taxa of amphibians ( Bufo bufo, Bufotes gr. B. viridis, Hyla gr. H. Arborea and Rana (s.l.) sp.), four taxa of reptiles ( Testudo hermanni, Podarcis sp., Zamenis gr. Z. longissimus, Natrix natrix ), and nine taxa of small mammals ( Erinaceus europaeus, Crocidura suaveolens, Arvicola italicus, Microtus (Terricola) savii, Microtus (Microtus) arvalis, Apodemus gr. A. sylvaticus - A. flavicollis, Hystrix (Acanthion) vinogradovi, Oryctolagus cuniculus and Lepus corsicanus ). From a biochronological point of view, the data on small and large vertebrates indicate an age between the beginning of the Late Pleistocene (MIS 5e) and the central part of MIS 3. The most recent fossiliferous layer (bed 8) is likely to have been deposited during a cooler period when compared to the previous layers.The data from small fossil vertebrates combined with those emerging from the large mammals and birds evidence the presence, near the karstic cavity, of open spaces (prairies) with pools of water, bordered by wooded areas and, not far, the presence of a rocky coastline.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"20 1","pages":"122"},"PeriodicalIF":0.7,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87854130","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}
Gruta do Caldeirao is an archaeological cave site located in Tomar (Portugal, western Iberian Peninsula), which contains an important Late Pleistocene sequence from Middle Paleolithic (Mousterian) to Upper Paleolithic (Solutrean-Magdalenian), including lithic tools, human remains, and other large- and small-vertebrate remains. Our revision and interpretation of the rodent assemblage previously published in the 1990s leads to three important conclusions: 1) the only species of the subgenus Iberomys present in the sequence is the current endemic Iberian vole species Microtus (Iberomys) cabrerae (Cabrera’s vole); 2) the rodent assemblage is dominated throughout by open-forest species, such as the long-tailed field mouse ( Apodemus sylvaticus ), and species associated with open-humid areas such as the Mediterranean and Lusitanian pine voles ( Microtus (Terricola ) spp.), with the notable presence of an extinct hamster ( Allocricetus bursae ) in layer K, and three vole species not currently found in the vicinity of the cave ( Microtus arvalis [the common vole], M. Agrestis [the field vole], and Chionomys nivalis [the European snow vole]) also in the assemblage; 3) the bioclimatic model, which is used to reconstruct climatic parameters on the basis of the rodent association, corroborates the proposal that the Solutrean occupation from layers H to Fa took place during a cold period equated to the Last Glacial Maximum (LGM), as indicated by the available radiocarbon dates and supported by the magnetic susceptibility data.
{"title":"Nota sobre la taxonomía de Microtus (Iberomys) (Arvicolinae, Rodentia) del Pleistoceno superior de la Gruta do Caldeirão (Tomar, Portugal) e interpretación paleoclimática de la asociación de roedores","authors":"J. López-García, L. Póvoas, J. Zilhão","doi":"10.3989/egeol.43622.542","DOIUrl":"https://doi.org/10.3989/egeol.43622.542","url":null,"abstract":"Gruta do Caldeirao is an archaeological cave site located in Tomar (Portugal, western Iberian Peninsula), which contains an important Late Pleistocene sequence from Middle Paleolithic (Mousterian) to Upper Paleolithic (Solutrean-Magdalenian), including lithic tools, human remains, and other large- and small-vertebrate remains. Our revision and interpretation of the rodent assemblage previously published in the 1990s leads to three important conclusions: 1) the only species of the subgenus Iberomys present in the sequence is the current endemic Iberian vole species Microtus (Iberomys) cabrerae (Cabrera’s vole); 2) the rodent assemblage is dominated throughout by open-forest species, such as the long-tailed field mouse ( Apodemus sylvaticus ), and species associated with open-humid areas such as the Mediterranean and Lusitanian pine voles ( Microtus (Terricola ) spp.), with the notable presence of an extinct hamster ( Allocricetus bursae ) in layer K, and three vole species not currently found in the vicinity of the cave ( Microtus arvalis [the common vole], M. Agrestis [the field vole], and Chionomys nivalis [the European snow vole]) also in the assemblage; 3) the bioclimatic model, which is used to reconstruct climatic parameters on the basis of the rodent association, corroborates the proposal that the Solutrean occupation from layers H to Fa took place during a cold period equated to the Last Glacial Maximum (LGM), as indicated by the available radiocarbon dates and supported by the magnetic susceptibility data.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"48 1","pages":"128"},"PeriodicalIF":0.7,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75721361","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}
This work reports the first record in the Internal Zones of the Betic Cordillera of a vertebrate fossil remain, more exactly a rib, corresponding to a marine reptile (Sauropterygia). The development of epicontinental platforms restricted to the Tethys Ocean during the fragmentation of Pangea since the late Lower Triassic favoured the radiation of Sauropterygia, diapsid marine reptiles including Placodontiformes, Pachypleurosauria, Nothosauroidea, and Pistosauroidea. The Triassic of the Alpujarride Complex, in the Internal Zones of the Betic Cordillera, SE Spain, comprises the carbonate deposits of these epicontinental platforms developed during the Middle-Late Triassic in the northern margin of the Mesomediterranean Massif. The studied stratigraphic interval is located at Sierra de Lujar (Granada Province) and consists of 17.5-m thick succession of alternating fossiliferous marls and limestones with local intense bioturbation and abundance of macroinvertebrates. The studied interval represents shallow facies of the inter- to subtidal environment as deduced by the record of Lofer cycles and the record of carbonated breccia at the top of the sequence likely related to storm events. Lofer cycles display lamination at their bases and intense bioturbation and abundant bivalves towards the top. A 15-cm long dorsal rib of a sauropterygian, likely a nothosaur, was recorded in this succession. It is well preserved, without evidence of original fragmentation, borings, or encrustations. This study shows for the first time fossil bones of marine reptiles in the Alpujarride Complex, which inhabited the shallow-water environments during the Triassic, equivalent to the marine reptiles recorded in other areas such as the Iberian Palaeomargin and other central Europe basins.
这项工作报告了在北部山内部区域的脊椎动物化石遗迹的第一个记录，更确切地说，是一根肋骨，对应于海洋爬行动物(蜥脚类)。下三叠世晚期泛大陆分裂时期，特提斯洋的陆表台地的发育有利于龙齿目、平齿目、厚齿目、Nothosauroidea和Pistosauroidea等双翅目海洋爬行动物的繁衍。Alpujarride杂岩三叠纪位于西班牙东南部Betic Cordillera内部带，由中晚三叠世在地中海地块北缘发育的陆表台地的碳酸盐矿床组成。研究的地层层段位于Sierra de Lujar (Granada省)，由17.5 m厚的泥灰岩和灰岩交替演替组成，具有强烈的生物扰动和丰富的大型无脊椎动物。根据Lofer旋回记录和层序顶部可能与风暴事件有关的碳酸化角砾岩记录推断，所研究的层序代表了潮间至潮下环境的浅层相。Lofer旋回底部呈层压状，顶部有强烈的生物扰动和丰富的双壳类。在这个演替过程中，有一根15厘米长的背肋骨被记录下来，它可能是一种nothosaurus。它保存完好，没有原始破碎、钻孔或结壳的迹象。该研究首次在三叠纪时期生活在浅水环境的Alpujarride杂岩中发现了海洋爬行动物的骨骼化石，与其他地区如伊比利亚古边缘纪和其他中欧盆地中记录的海洋爬行动物相当。
{"title":"Primer registro de reptiles marinos triásicos (notosaurios, sauropterigios) del Complejo Alpujárride (Zonas Internas de la Cordillera Bética, España)","authors":"Matías Reolid, Jesús Reolid","doi":"10.3989/egeol.43592.535","DOIUrl":"https://doi.org/10.3989/egeol.43592.535","url":null,"abstract":"This work reports the first record in the Internal Zones of the Betic Cordillera of a vertebrate fossil remain, more exactly a rib, corresponding to a marine reptile (Sauropterygia). The development of epicontinental platforms restricted to the Tethys Ocean during the fragmentation of Pangea since the late Lower Triassic favoured the radiation of Sauropterygia, diapsid marine reptiles including Placodontiformes, Pachypleurosauria, Nothosauroidea, and Pistosauroidea. The Triassic of the Alpujarride Complex, in the Internal Zones of the Betic Cordillera, SE Spain, comprises the carbonate deposits of these epicontinental platforms developed during the Middle-Late Triassic in the northern margin of the Mesomediterranean Massif. The studied stratigraphic interval is located at Sierra de Lujar (Granada Province) and consists of 17.5-m thick succession of alternating fossiliferous marls and limestones with local intense bioturbation and abundance of macroinvertebrates. The studied interval represents shallow facies of the inter- to subtidal environment as deduced by the record of Lofer cycles and the record of carbonated breccia at the top of the sequence likely related to storm events. Lofer cycles display lamination at their bases and intense bioturbation and abundant bivalves towards the top. A 15-cm long dorsal rib of a sauropterygian, likely a nothosaur, was recorded in this succession. It is well preserved, without evidence of original fragmentation, borings, or encrustations. This study shows for the first time fossil bones of marine reptiles in the Alpujarride Complex, which inhabited the shallow-water environments during the Triassic, equivalent to the marine reptiles recorded in other areas such as the Iberian Palaeomargin and other central Europe basins.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"24 1","pages":"126"},"PeriodicalIF":0.7,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84584803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The El Aouana igneous rocks are part of the Miocene magmatic suite that extends from Northern Tunisia to Morocco through the Algerian coast in the Maghrebin chain. These rocks are composed of volcanic (andesites and dacites) and subvolcanic (micodiorites and microgranodiorites) lithologies that intruded both the Cretaceous and Oligo-Miocene nappes, and the Miocene post-nappe sediments. The andesites are composed of plagioclase, amphibole and pyroxene phenocrysts that are set in a microlithic groundmass. The dacites are plagioclase-rich and rare, highly altered ferromagnesian minerals. The microdiorites and microgranodiorites are hornblende-bearing rocks with plagioclase, pyroxene and rare biotite phenocrysts that are set in a microcrystalline groundmass. Geochemical observations show that the rocks are calc-alkaline with I-type affinity. They are enriched in large ion lithophile elements (LILE) and light rare earth elements (LREE) compared to high field strength elements (HFSE) and heavy rare earth elements (HREE). The negative Nb, P and Ti anomalies observed on the multi-element patterns are imprints of magmas originated from subduction zones. Field, petrological and geochemical investigations show that the El Aouana Miocene igneous rocks are emplaced in a post-collisionnal setting. These rocks show similarities with the metaluminous, post-collisionnel granitoids of north-eastern Algeria which are thought to have been derived from a metasomatized mantle source as a consequence of ‘slab break-off’ underneath the North African margin.
El Aouana火成岩是中新世岩浆套的一部分，从突尼斯北部延伸到摩洛哥，穿过阿尔及利亚海岸的Maghrebin链。这些岩石由火山(安山岩和英安岩)和次火山(微闪长岩和微花岗闪长岩)岩性组成，它们侵入了白垩纪和渐新世-中新世推覆体以及中新世后推覆体沉积物。安山岩由斜长石、角闪石和辉石斑晶组成，形成于微岩屑地块中。英安岩是富斜长石的稀有高蚀变镁铁矿物。微闪长岩和微花岗闪长岩是一种角闪石环状岩石，具有斜长石、辉石和罕见的黑云母斑晶，镶嵌在微晶地块中。地球化学观测表明，岩石呈钙碱性，具有i型亲和力。与高场强元素(HFSE)和重稀土元素(HREE)相比，它们富含大离子亲石元素(LILE)和轻稀土元素(LREE)。在多元素模式上观察到的负Nb、P和Ti异常是源自俯冲带的岩浆的印记。野外、岩石学和地球化学调查表明，El Aouana中新世火成岩位于后碰撞环境中。这些岩石与阿尔及利亚东北部的含金属、碰撞后花岗岩类相似，后者被认为来自北非边缘下“板块断裂”的交代地幔源。
{"title":"Caractéristiques pétrologiques et géochimiques des roches magmatiques d’El Aouana, NE algérien","authors":"H. Hamlaoui, R. Laouar, S. Bouhlel, A. J. Boyce","doi":"10.3989/egeol.43391.510","DOIUrl":"https://doi.org/10.3989/egeol.43391.510","url":null,"abstract":"The El Aouana igneous rocks are part of the Miocene magmatic suite that extends from Northern Tunisia to Morocco through the Algerian coast in the Maghrebin chain. These rocks are composed of volcanic (andesites and dacites) and subvolcanic (micodiorites and microgranodiorites) lithologies that intruded both the Cretaceous and Oligo-Miocene nappes, and the Miocene post-nappe sediments. The andesites are composed of plagioclase, amphibole and pyroxene phenocrysts that are set in a microlithic groundmass. The dacites are plagioclase-rich and rare, highly altered ferromagnesian minerals. The microdiorites and microgranodiorites are hornblende-bearing rocks with plagioclase, pyroxene and rare biotite phenocrysts that are set in a microcrystalline groundmass. Geochemical observations show that the rocks are calc-alkaline with I-type affinity. They are enriched in large ion lithophile elements (LILE) and light rare earth elements (LREE) compared to high field strength elements (HFSE) and heavy rare earth elements (HREE). The negative Nb, P and Ti anomalies observed on the multi-element patterns are imprints of magmas originated from subduction zones. Field, petrological and geochemical investigations show that the El Aouana Miocene igneous rocks are emplaced in a post-collisionnal setting. These rocks show similarities with the metaluminous, post-collisionnel granitoids of north-eastern Algeria which are thought to have been derived from a metasomatized mantle source as a consequence of ‘slab break-off’ underneath the North African margin.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"1 1","pages":"124"},"PeriodicalIF":0.7,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89807639","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}
In the southeastern Iberian Range, several mainly volcaniclastic rocks resulting from submarine eruptions can be found interbedded in the Lower‒Middle Jurassic carbonate succession. The geological mapping of the outcropping volcanic rocks reveals that they follow three well marked lineaments of cortical weakness (Teruel, Caudiel and Alcublas Fault Zones), probably caused by the faulting related to the opening and sea‒floor spreading of the Ligurian and Alpine Tethys oceans. The present work introduces the results of the study, which aims to evaluate the tectonosedimentary evolution of a shallow submarine setting affected by volcanism during the Aalenian‒Bajocian boundary (Middle Jurassic). This site, known as “Caudiel volcanic outcrop”, is located at the southeastern part of the Caudiel Fault Zone. The presence of positive subaqueous volcaniclastic reliefs, added to shallow marine platforms, strongly affects the depth‒dependent carbonate sedimentation: it induces substantial changes in lithofacies compared to other neighboring areas, or even directly prevents the sedimentation. Moreover, episodic normal fault activity generated a dynamic topography over time, with variable rates of both subsidence and uplifting throughout different areas. The Caudiel outcrop represents a good ancient example of interaction between multiple factors (volcanism, tectonism and sedimentation) in shallow carbonate platforms, where the accommodation changes and the sedimentation rates seem to be subordinate to the local tectonic disturbances.
{"title":"Interacción entre vulcanismo, tectónica y sedimentación en una plataforma carbonatada somera: Ejemplo en el Tethys occidental (Jurásico Medio, sureste de la Cordillera Ibérica)","authors":"J. E. Cortés","doi":"10.3989/egeol.43590.537","DOIUrl":"https://doi.org/10.3989/egeol.43590.537","url":null,"abstract":"In the southeastern Iberian Range, several mainly volcaniclastic rocks resulting from submarine eruptions can be found interbedded in the Lower‒Middle Jurassic carbonate succession. The geological mapping of the outcropping volcanic rocks reveals that they follow three well marked lineaments of cortical weakness (Teruel, Caudiel and Alcublas Fault Zones), probably caused by the faulting related to the opening and sea‒floor spreading of the Ligurian and Alpine Tethys oceans. The present work introduces the results of the study, which aims to evaluate the tectonosedimentary evolution of a shallow submarine setting affected by volcanism during the Aalenian‒Bajocian boundary (Middle Jurassic). This site, known as “Caudiel volcanic outcrop”, is located at the southeastern part of the Caudiel Fault Zone. The presence of positive subaqueous volcaniclastic reliefs, added to shallow marine platforms, strongly affects the depth‒dependent carbonate sedimentation: it induces substantial changes in lithofacies compared to other neighboring areas, or even directly prevents the sedimentation. Moreover, episodic normal fault activity generated a dynamic topography over time, with variable rates of both subsidence and uplifting throughout different areas. The Caudiel outcrop represents a good ancient example of interaction between multiple factors (volcanism, tectonism and sedimentation) in shallow carbonate platforms, where the accommodation changes and the sedimentation rates seem to be subordinate to the local tectonic disturbances.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"447 1","pages":"129"},"PeriodicalIF":0.7,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86315138","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}
Recent excavations at Aves Cave I (AC), Brad Pit ‘A’ (BPA), Milo ‘A’ (MA), Bridge Cave (BC) and Alcelaphine Cave (AL), in the Cradle of Humankind, Gauteng, South Africa, have yielded fossil suid remains which provide biostratigraphic information about the periods of deposition in the Bolt’s Farm Palaeokarst System. At Aves Cave I there are Late Pliocene deposits which have yielded the extinct suid Potamochoeroides hypsodon , including skeletal elements that were poorly represented in previous collections from Bolt’s Farm as well as rare remains of Notochoerus capensis . At Brad Pit ‘A’ remains of Gerontochoerus koobiforaensis occur. Milo ‘A’ and other deposits have yielded remains of the suid Metridiochoerus andrewsi that indicate a later phase of endokarst sedimentation (Early Pleistocene). The Panthera Spot at Bridge Cave has yielded articulated foot bones of a suid, provisionally identified as Phacochoerus modestus and which suggest an Early Pleistocene age for this infilling. The augmented samples of suids from Bolt’s Farm invite detailed comparisons with the Suidae from Makapansgat which permits a review of the taxonomy of Notochoerus and Potamochoeroides . It is shown that both genera are Suinae, and could be synonyms. Comparisons are also made with Plio-Pleistocene suids from Malawi and Namibia.
最近在南非豪登省人类摇篮的avescave I (AC)， Brad Pit ' A ' (BPA)， Milo ' A ' (MA)， Bridge Cave (BC)和Alcelaphine Cave (AL)的挖掘工作中，发现了化石液体残骸，这些化石液体残骸提供了关于Bolt ' s Farm古火山岩系统沉积时期的生物地层学信息。在avesi洞穴，有上新世晚期的沉积物，其中发现了已经灭绝的suamochoeroides hypsodon，包括博尔特农场以前收集的很少代表的骨骼元素，以及罕见的capensis Notochoerus的遗骸。在Brad Pit ' A '出现了koobiforaensis的Gerontochoerus遗骸。Milo ' A '和其他矿床已经发现了Metridiochoerus andrewsi的残骸，表明喀斯特内沉积的后期(早更新世)。桥洞的Panthera Spot发现了一种水龙的关节足骨，暂时被鉴定为Phacochoerus modestus，这表明这种填充物的时代是早更新世。来自博尔特农场的增加的水蛭样本可以与来自马卡潘斯加特的水蛭科进行详细的比较，从而可以对Notochoerus和Potamochoeroides的分类进行回顾。结果表明，这两个属都是水獭科，可能是近义词。并与马拉维和纳米比亚的上新世-更新世水样进行了比较。
{"title":"Suidos fósiles del Sistema paleokárstico de Bolt's Farm, Sudáfrica: implicaciones para la taxonomía y biocronología de Potamochoeroides y los Notochoerus","authors":"M. Pickford, D. Gommery","doi":"10.3989/egeol.43542.536","DOIUrl":"https://doi.org/10.3989/egeol.43542.536","url":null,"abstract":"Recent excavations at Aves Cave I (AC), Brad Pit ‘A’ (BPA), Milo ‘A’ (MA), Bridge Cave (BC) and Alcelaphine Cave (AL), in the Cradle of Humankind, Gauteng, South Africa, have yielded fossil suid remains which provide biostratigraphic information about the periods of deposition in the Bolt’s Farm Palaeokarst System. At Aves Cave I there are Late Pliocene deposits which have yielded the extinct suid Potamochoeroides hypsodon , including skeletal elements that were poorly represented in previous collections from Bolt’s Farm as well as rare remains of Notochoerus capensis . At Brad Pit ‘A’ remains of Gerontochoerus koobiforaensis occur. Milo ‘A’ and other deposits have yielded remains of the suid Metridiochoerus andrewsi that indicate a later phase of endokarst sedimentation (Early Pleistocene). The Panthera Spot at Bridge Cave has yielded articulated foot bones of a suid, provisionally identified as Phacochoerus modestus and which suggest an Early Pleistocene age for this infilling. The augmented samples of suids from Bolt’s Farm invite detailed comparisons with the Suidae from Makapansgat which permits a review of the taxonomy of Notochoerus and Potamochoeroides . It is shown that both genera are Suinae, and could be synonyms. Comparisons are also made with Plio-Pleistocene suids from Malawi and Namibia.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"1 1","pages":"127"},"PeriodicalIF":0.7,"publicationDate":"2020-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73900159","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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