Pub Date : 2021-03-24DOI: 10.22201/CGEO.20072902E.2021.1.1598
Lourdes Omaña, J. Pons, R. Cruz
During the Maastrichtian, two lithostratigraphic units were deposited in the central Chiapas region; the Ocozocoautla and Angostura formations. The first unit crops out northwest of the city of Tuxtla Gutiérrez in central Chiapas. It is a complex lithological unit mainly composed of siliciclastic rocks interbedded with limestone. Overlying it, the Angostura limestone is recognized. This study focuses on a taxonomic study of the larger benthic and planktic foraminifera from both formations in order to assign age and to infer the paleoenviroment. The Ocozocoautla Formation includes an association of benthic as well as significant planktic foraminifera. Based on the microfossils stratigraphic distribution, two biozones were defined: the Pseudorbitoides rutteni–Ayalaina rutteni Assemblage Zone of earliest Maastrichtian and the upper part of the Gansserina gansseri Interval Zone of early Maastrichtian. The Angostura Formation contains dasycladacean algae and larger foraminifera considered as important age markers in shallowwater environments. Two foraminiferal interval zones were defined, Praechubbina breviclaustra Interval Zone of early late Maastrichtian and Chubbina jamaicensis Total Range Zone of late to latest Maastrichian age. The microfacies (grainstone, wackestone–packstone, wackestone) as well as the foraminiferal assemblage enable the paleoenvironment to be reconstructed, suggesting a deposit that developed in an openwater marine setting with moderate to high energy, characterized by benthic and planktic foraminifera in the Ocozocoautla Formation, while in the Angostura Formation a shallow-water marine protected environment is inferred. The paleobiogeographical distribution of the assemblage from both the Ocozocoautla and Angostura formations mostly contains endemic benthic foraminifera of the Caribbean Province and other few Tethysian forms of the Angostura Formation.
{"title":"Biostratigraphy and paleoenvironment of Maastrichtian foraminiferal assemblages from a succession located NW of Tuxtla Gutiérrez, Chiapas (SE Mexico)","authors":"Lourdes Omaña, J. Pons, R. Cruz","doi":"10.22201/CGEO.20072902E.2021.1.1598","DOIUrl":"https://doi.org/10.22201/CGEO.20072902E.2021.1.1598","url":null,"abstract":"During the Maastrichtian, two lithostratigraphic units were deposited in the central Chiapas region; the Ocozocoautla and Angostura formations. The first unit crops out northwest of the city of Tuxtla Gutiérrez in central Chiapas. It is a complex lithological unit mainly composed of siliciclastic rocks interbedded with limestone. Overlying it, the Angostura limestone is recognized. This study focuses on a taxonomic study of the larger benthic and planktic foraminifera from both formations in order to assign age and to infer the paleoenviroment. The Ocozocoautla Formation includes an association of benthic as well as significant planktic foraminifera. Based on the microfossils stratigraphic distribution, two biozones were defined: the Pseudorbitoides rutteni–Ayalaina rutteni Assemblage Zone of earliest Maastrichtian and the upper part of the Gansserina gansseri Interval Zone of early Maastrichtian. The Angostura Formation contains dasycladacean algae and larger foraminifera considered as important age markers in shallowwater environments. Two foraminiferal interval zones were defined, Praechubbina breviclaustra Interval Zone of early late Maastrichtian and Chubbina jamaicensis Total Range Zone of late to latest Maastrichian age. The microfacies (grainstone, wackestone–packstone, wackestone) as well as the foraminiferal assemblage enable the paleoenvironment to be reconstructed, suggesting a deposit that developed in an openwater marine setting with moderate to high energy, characterized by benthic and planktic foraminifera in the Ocozocoautla Formation, while in the Angostura Formation a shallow-water marine protected environment is inferred. The paleobiogeographical distribution of the assemblage from both the Ocozocoautla and Angostura formations mostly contains endemic benthic foraminifera of the Caribbean Province and other few Tethysian forms of the Angostura Formation.","PeriodicalId":49601,"journal":{"name":"Revista Mexicana De Ciencias Geologicas","volume":"29 1","pages":"65-81"},"PeriodicalIF":0.8,"publicationDate":"2021-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78231640","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 : 2021-03-24DOI: 10.22201/CGEO.20072902E.2021.1.1600
A. Quesada-Román, Néstor Campos, Sebastián Granados-Bolaños
Numerous high elevation tropical mountains around the world show evidence of past glacial activity during the Last Glacial Maximum (LGM). Cerro Chirripó in Costa Rica exhibits paleoglacial landforms such as glacial cirques, moraine deposits and polished and striated bedrock surfaces. We used aerial imagery (1:25000) and contour lines to develop a Digital Elevation Model (DEM) for the LGM. We determined paleo-equilibrium line altitudes (paleo-ELAs) using AreaAltitude Balance Ratio (AABR) during the LGM for Cerro Chirripó in Costa Rica. Additionally, a Generalized Linear Model (GLM) was performed to statistically analyze the paleoglacier volumes and ice thickness combined with ten land surface parameters (LSP). Our results identified thirty-one paleoglaciers covering an area of 28.26 km2 during the global LGM, with a maximum ice thickness of 178 meters in Cerro Chirripó, a total volume of 13863 × 105 m3 and a mean paleo-ELA of 3490 meters. In addition, Area and Slope were the LSP with the highest statistical correlation to explain the paleoglacier volumes, while Area and Diurnal Anisotropic Heating were best for the paleoglacier ice thickness. As one of the first studies in the tropical high mountain environments, this work expands the geographic scope of glacier volume and thickness reconstructions during the maximum expansion of the LGM.
{"title":"Tropical glacier reconstructions during the Last Glacial Maximum in Costa Rica","authors":"A. Quesada-Román, Néstor Campos, Sebastián Granados-Bolaños","doi":"10.22201/CGEO.20072902E.2021.1.1600","DOIUrl":"https://doi.org/10.22201/CGEO.20072902E.2021.1.1600","url":null,"abstract":"Numerous high elevation tropical mountains around the world show evidence of past glacial activity during the Last Glacial Maximum (LGM). Cerro Chirripó in Costa Rica exhibits paleoglacial landforms such as glacial cirques, moraine deposits and polished and striated bedrock surfaces. We used aerial imagery (1:25000) and contour lines to develop a Digital Elevation Model (DEM) for the LGM. We determined paleo-equilibrium line altitudes (paleo-ELAs) using AreaAltitude Balance Ratio (AABR) during the LGM for Cerro Chirripó in Costa Rica. Additionally, a Generalized Linear Model (GLM) was performed to statistically analyze the paleoglacier volumes and ice thickness combined with ten land surface parameters (LSP). Our results identified thirty-one paleoglaciers covering an area of 28.26 km2 during the global LGM, with a maximum ice thickness of 178 meters in Cerro Chirripó, a total volume of 13863 × 105 m3 and a mean paleo-ELA of 3490 meters. In addition, Area and Slope were the LSP with the highest statistical correlation to explain the paleoglacier volumes, while Area and Diurnal Anisotropic Heating were best for the paleoglacier ice thickness. As one of the first studies in the tropical high mountain environments, this work expands the geographic scope of glacier volume and thickness reconstructions during the maximum expansion of the LGM.","PeriodicalId":49601,"journal":{"name":"Revista Mexicana De Ciencias Geologicas","volume":"16 1","pages":"55-64"},"PeriodicalIF":0.8,"publicationDate":"2021-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84547149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-24DOI: 10.22201/cgeo.20072902e.2020.3.1570
Jeny Alejandra Grajales, A. F. Nieto-Samaniego, Darío Barrero Lozano, J. A. Osorio, M. A. Cuéllar
The Cretaceous and Paleogene magmatic arcs of the Central and Western Cordilleras of Colombia have been attributed to the evolution of a subduction system in the Colombian Pacific coast. In this work the distribution and crystallization ages of plutons emplaced between 60 Ma and 53 Ma in the Central and Western Cordilleras are analyzed. From 53 Ma the magmatic arc migrates towards the west of Colombia, installing magmas in a plate edge transitional crust. The crystallization ages analyzed in this work suggest that, within the study area, the plutonic belt is continuous throughout the Western Cordillera. From 40±5 Ma to 26 Ma there was a significant reduction in the convergence velocity of the Farallon plate; as it decreases, also the tectonic loading diminishes resulting in a process of regional stress relaxation. The process of relaxation of the regional stress also occurred in the intra-continental environments producing peneplanization process in the topographic highs of northern Colombia, the reactivation of the piedmont with westwards progradation of sedimentation and the development of a middle- to late-Eocene regional unconformity. In continental shelf environments, the relaxation of the tectonic stress is evidenced by the distribution of reef limestone sequences throughout the Colombian Pacific margin and the Caribbean of Colombia, Ecuador, Panama and Costa Rica, and by a magmatic gap from 33 Ma to 26 Ma. The Paleocene-Eocene magmatic event distributed in the Central and Western Cordilleras took place under a transtensional regime, with the maximum horizontal compressive stress (σ1) oriented SW-NE, product of the oblique convergence between the Farallon and South American plates.
{"title":"Emplacement of Paleocene-Eocene magmatism under transtensional regime and its evolution to a dynamic equilibrium on the western edge of Colombia","authors":"Jeny Alejandra Grajales, A. F. Nieto-Samaniego, Darío Barrero Lozano, J. A. Osorio, M. A. Cuéllar","doi":"10.22201/cgeo.20072902e.2020.3.1570","DOIUrl":"https://doi.org/10.22201/cgeo.20072902e.2020.3.1570","url":null,"abstract":"The Cretaceous and Paleogene magmatic arcs of the Central and Western Cordilleras of Colombia have been attributed to the evolution of a subduction system in the Colombian Pacific coast. In this work the distribution and crystallization ages of plutons emplaced between 60 Ma and 53 Ma in the Central and Western Cordilleras are analyzed. From 53 Ma the magmatic arc migrates towards the west of Colombia, installing magmas in a plate edge transitional crust. The crystallization ages analyzed in this work suggest that, within the study area, the plutonic belt is continuous throughout the Western Cordillera. From 40±5 Ma to 26 Ma there was a significant reduction in the convergence velocity of the Farallon plate; as it decreases, also the tectonic loading diminishes resulting in a process of regional stress relaxation. The process of relaxation of the regional stress also occurred in the intra-continental environments producing peneplanization process in the topographic highs of northern Colombia, the reactivation of the piedmont with westwards progradation of sedimentation and the development of a middle- to late-Eocene regional unconformity. In continental shelf environments, the relaxation of the tectonic stress is evidenced by the distribution of reef limestone sequences throughout the Colombian Pacific margin and the Caribbean of Colombia, Ecuador, Panama and Costa Rica, and by a magmatic gap from 33 Ma to 26 Ma. The Paleocene-Eocene magmatic event distributed in the Central and Western Cordilleras took place under a transtensional regime, with the maximum horizontal compressive stress (σ1) oriented SW-NE, product of the oblique convergence between the Farallon and South American plates.","PeriodicalId":49601,"journal":{"name":"Revista Mexicana De Ciencias Geologicas","volume":"303 1","pages":"250-268"},"PeriodicalIF":0.8,"publicationDate":"2020-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76264280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-24DOI: 10.22201/cgeo.20072902e.2020.3.1580
M. Kunath, George Phillips, R. Clary
The gryphaeid oyster Exogyra Say, 1820, is ubiquitous in Upper Cretaceous sediments in the southeastern United States. Like many oysters (Order Ostreida), Exogyra attached its shell to hard surfaces on the seafloor by means of cementation. Throughout its lifetime, Exogyra may preserve through bioimmuration the characteristics and even skeletal remains of substrate organisms, including mollusk shells, echinoids, and bryozoans. Exogyra costata of all sizes were collected from three different localities within upper Maastrichtian deposits in northeast Mississippi and their bioimmurations analyzed. Substrates were identified and classified to compare the three localities’ substrate taxa in order to probe differences in benthic population structure. The results of this pilot study provide an overview of available surfaces on the Late Cretaceous seafloor on the eastern side of the Mississippi Embayment. The data suggest that taxonomic diversity among utilized substrates may increase from north to south, which corresponds to increasing depth from shallow marine to deeper sediments on the shelf.
{"title":"Cretaceous cultch: substrate availability for oyster Exogyra in the Maastrichtian of the eastern Mississippi Embayment","authors":"M. Kunath, George Phillips, R. Clary","doi":"10.22201/cgeo.20072902e.2020.3.1580","DOIUrl":"https://doi.org/10.22201/cgeo.20072902e.2020.3.1580","url":null,"abstract":"The gryphaeid oyster Exogyra Say, 1820, is ubiquitous in Upper Cretaceous sediments in the southeastern United States. Like many oysters (Order Ostreida), Exogyra attached its shell to hard surfaces on the seafloor by means of cementation. Throughout its lifetime, Exogyra may preserve through bioimmuration the characteristics and even skeletal remains of substrate organisms, including mollusk shells, echinoids, and bryozoans. Exogyra costata of all sizes were collected from three different localities within upper Maastrichtian deposits in northeast Mississippi and their bioimmurations analyzed. Substrates were identified and classified to compare the three localities’ substrate taxa in order to probe differences in benthic population structure. The results of this pilot study provide an overview of available surfaces on the Late Cretaceous seafloor on the eastern side of the Mississippi Embayment. The data suggest that taxonomic diversity among utilized substrates may increase from north to south, which corresponds to increasing depth from shallow marine to deeper sediments on the shelf.","PeriodicalId":49601,"journal":{"name":"Revista Mexicana De Ciencias Geologicas","volume":"51 1","pages":"197-211"},"PeriodicalIF":0.8,"publicationDate":"2020-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89641512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-24DOI: 10.22201/cgeo.20072902e.2020.3.1583
B. Prado, L. Mora, T. Abbruzzini, Sebastian Flores, S. Cram, P. Ortega, A. Navarrete, C. Siebe
An alternative for sustainable urban development is to revegetate cities with the construction of planters as well as to recover degraded sites. The objective of this work was to characterize urban waste materials produced in Mexico City and to evaluate their potential for constructing Technosols for plant growth, as an alternative to use in revegetating the city without affecting natural landscapes. Construction and demolition waste materials amended with different application rates of compost made out of gardening wastes from Mexico City green areas were tested. Nine mixtures were prepared; three based on concrete, three based on demolition waste and three based on excavation waste. Changes on physical, chemical and physicochemical properties of these mixtures, namely nutrient contents, water retention and aeration capacity, were monitored in a twelve-month experiment. The mineralogy and the risk regarding the release of heavy metals and trace elements were also evaluated in the soluble fraction. The constructed Technosols were appropriate, to a greater or lesser extent, for tomato plant growth. Soil pH and soil electrical conductivity (EC) were the main factors defining their suitability; both parameters changed over time due to the washing of salts. The particle size of the mineral materials as well as the application rates of compost used in the construction of the Technosols resulted in adequate water holding capacity and soil aeration for plant growth. The type of parental materials defined the majority of the Technosol characteristics as well as their ability to function as a plant support. The concentrations of readily available heavy and trace metals were not a limitation for plant growth. However, potential co-transport of these elements with soluble organic matter should be considered in further research.
{"title":"Feasibility of urban waste for constructing Technosols for plant growth","authors":"B. Prado, L. Mora, T. Abbruzzini, Sebastian Flores, S. Cram, P. Ortega, A. Navarrete, C. Siebe","doi":"10.22201/cgeo.20072902e.2020.3.1583","DOIUrl":"https://doi.org/10.22201/cgeo.20072902e.2020.3.1583","url":null,"abstract":"An alternative for sustainable urban development is to revegetate cities with the construction of planters as well as to recover degraded sites. The objective of this work was to characterize urban waste materials produced in Mexico City and to evaluate their potential for constructing Technosols for plant growth, as an alternative to use in revegetating the city without affecting natural landscapes. Construction and demolition waste materials amended with different application rates of compost made out of gardening wastes from Mexico City green areas were tested. Nine mixtures were prepared; three based on concrete, three based on demolition waste and three based on excavation waste. Changes on physical, chemical and physicochemical properties of these mixtures, namely nutrient contents, water retention and aeration capacity, were monitored in a twelve-month experiment. The mineralogy and the risk regarding the release of heavy metals and trace elements were also evaluated in the soluble fraction. The constructed Technosols were appropriate, to a greater or lesser extent, for tomato plant growth. Soil pH and soil electrical conductivity (EC) were the main factors defining their suitability; both parameters changed over time due to the washing of salts. The particle size of the mineral materials as well as the application rates of compost used in the construction of the Technosols resulted in adequate water holding capacity and soil aeration for plant growth. The type of parental materials defined the majority of the Technosol characteristics as well as their ability to function as a plant support. The concentrations of readily available heavy and trace metals were not a limitation for plant growth. However, potential co-transport of these elements with soluble organic matter should be considered in further research.","PeriodicalId":49601,"journal":{"name":"Revista Mexicana De Ciencias Geologicas","volume":"41 1","pages":"237-249"},"PeriodicalIF":0.8,"publicationDate":"2020-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86473414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-24DOI: 10.22201/cgeo.20072902e.2020.3.1586
Alexander Sánchez-Duque, F. Bautista, Rubén Cejudo, Avto Goguitchaichvili, M. Cervantes-Solano
We present a study of environmental magnetism in order to determine the relationship between magnetic parameters and heavy metals in urban soils of the Metropolitan Area of Valle de Aburrá (MAVA), Colombia, in order to establish magnetic indicators that allow estimating concentrations of magnetic minerals, mayor elements, and Pb, and to determine the area of their accumulations in the urban zone of the Metropolitan Area of Valle de Aburrá. The study was carried out on 83 samples of topsoil, which were subject to magnetic analyses. The concentration of mayor elements (Al2O3, Fe2O3 y MnO) and Pb was determined by energy dispersive X Ray Fluorescence. A variation of magnetic material in the urban soils was Los parámetros magnéticos como indicadores de contaminación por elementos mayores y plomo en suelos urbanos del Valle de Aburrá, Colombia Alexander Sánchez-Duque1,3, Francisco Bautista1, Rubén Cejudo2,*, Avto Goguitchaichvili2 y Miguel Ángel Cervantes-Solano4 1 Laboratorio Universitario de Geofísica Ambiental (LUGA), Centro de Investigaciones en Geografía Ambiental (CIGA), Universidad Nacional Autónoma de México, Antigua Carretera a Pátzcuaro No. 8701, Col. Ex-Hacienda de San José de la Huerta, C.P. 58190, Morelia, Mich., México. 2 Laboratorio Universitario de Geofísica Ambiental (LUGA), Instituto de Geofísica Unidad Michoacán (IGUM), Universidad Nacional Autónoma de México, Antigua Carretera a Pátzcuaro No. 8701, Col. Ex-Hacienda de San José de la Huerta, C.P. 58190, Morelia, Mich., México. 3 Adscripción actual: Tecnológico Nacional de México, campus Valle de Morelia, km 6.5 Carretera Morelia-Salamanca, C.P. 58100, Morelia, Mich., México. 4 Escuela Nacional de Estudios Superiores Unidad Morelia, Antigua Carretera a Pátzcuaro 8701, C.P. 58190, Morelia, Mich., México. * ruben@igeofisica.unam.mx REVISTA MEXICANA DE CIENCIAS GEOLÓGICAS v. 37, núm. 3, 2020, p. 224-236 I: htt ://dx.doi.org/10.22201/cgeo.20072902e.2020.3.1586 225 Parámetros magnéticos como indicadores de contaminación RMCG | v. 37 | núm. 3 | www.rmcg.unam.mx | DOI: http://dx.doi.org/10.22201/cgeo.20072902e.2020.3.1586 found, which contain a mixture of magnetic minerals of low coercivity or natural magnetite of anthropogenic origin. Particles of superparamagnetic size were detected at medium and low concentrations in soils with low anthropic activity, suggesting a natural origin. On the other hand, by the combination of magnetic parameters and thermomagnetic curves we found high concentrations of magnetic minerals of anthropic origin in the soils. The concentrations of Al2O3 y Fe2O3 are high and similar in the urban soil. Soils from areas of residential and public space use, which have few emission sources of anthropogenic particles, showed low concentration of Pb. On the other hand, soils from areas of industrial and commercial use, with high anthropogenic activity (vehicular traffic), showed high concentration of Pb. Soils from public space areas with low anthropic activity were employ
我们提出了一项环境磁学研究，以确定哥伦比亚aburr山谷大都市区(MAVA)城市土壤中磁性参数与重金属之间的关系，以便建立磁性指标，从而可以估计磁性矿物、主要元素和Pb的浓度，并确定它们在aburr山谷大都市区的城市区域的积累面积。这项研究是在83个表土样本上进行的，这些样本需要进行磁分析。用能量色散X射线荧光法测定了主要元素(Al2O3、Fe2O3和MnO)和Pb的浓度。城市土壤中磁性物质的变化为Los parámetros magnacimicos como indicres de contaminación por elementos mayores y plomo en suelos urbanos del Valle de aburr Alexander Sánchez-Duque1,3, Francisco Bautista1, rubacimn Cejudo2，*， Avto Goguitchaichvili2 y Miguel Ángel Cervantes-Solano4 1 Geofísica环境大学实验室(LUGA)， Geografía环境调查中心(CIGA)，国立大学Autónoma de macimxico，Antigua Carretera a Pátzcuaro No. 8701，上校前庄园de San jossere de la Huerta, C.P. 58190，莫雷利亚，密歇根州。、墨西哥。2 . Geofísica环境大学实验室(LUGA)， Geofísica联合研究所Michoacán (IGUM)， Autónoma墨西哥国立大学，安提瓜卡雷雷拉，Pátzcuaro No. 8701, de San jossde la Huerta前庄园，C.P. 58190，密歇根州莫雷利亚、墨西哥。3 Adscripción实际地址:Tecnológico国立莫雷利亚大学，莫雷利亚山谷校区，公里6.5卡雷特·莫雷利亚-萨拉曼卡，C.P. 58100，密歇根州莫雷利亚、墨西哥。4 .国立莫雷利亚大学，安提瓜卡雷雷拉，Pátzcuaro 8701, C.P. 58190，密歇根州莫雷利亚、墨西哥。* ruben@igeofisica.unam.mx墨西哥科学研究GEOLÓGICAS v. 37, núm。3, 2020, p. 224-236 I: httt://dx.doi.org/10.22201/cgeo.20072902e.2020.3.1586 225 Parámetros magnacimticos como indices de contaminación RMCG | v. 37 | núm。3 | www.rmcg.unam.mx | DOI: http://dx.doi.org/10.22201/cgeo.20072902e.2020.3.1586发现，其中含有低矫顽力磁性矿物或人为来源的天然磁铁矿的混合物。在低人为活动的土壤中检测到中低浓度的超顺磁性颗粒，表明其自然来源。另一方面，通过磁参数和热磁曲线的结合，我们发现土壤中存在高浓度的人为磁性矿物。城市土壤中Al2O3和Fe2O3的浓度较高且相近。居住和公共空间利用区土壤中Pb浓度较低，人为颗粒物排放源较少。另一方面，人类活动(车辆交通)较多的工商区土壤Pb含量较高。利用低人为活动公共空间土壤确定各元素和磁性参数的参考阈值。统计分析表明，MAVA土壤中磁性矿物含量与Pb浓度成正比关系，与Al2O3、Fe2O3和MnO浓度成反比关系。我们建立了一个数学模型，根据磁性参数估计元素的浓度，精度为63%。46平方公里的区域(占市区面积的25%)出现了高磁性矿物积聚和高铅浓度，这是污染物质积聚可能造成健康风险的区域。
{"title":"Los parámetros magnéticos como indicadores de contaminación por elementos mayores y plomo en suelos urbanos del Valle de Aburrá, Colombia","authors":"Alexander Sánchez-Duque, F. Bautista, Rubén Cejudo, Avto Goguitchaichvili, M. Cervantes-Solano","doi":"10.22201/cgeo.20072902e.2020.3.1586","DOIUrl":"https://doi.org/10.22201/cgeo.20072902e.2020.3.1586","url":null,"abstract":"We present a study of environmental magnetism in order to determine the relationship between magnetic parameters and heavy metals in urban soils of the Metropolitan Area of Valle de Aburrá (MAVA), Colombia, in order to establish magnetic indicators that allow estimating concentrations of magnetic minerals, mayor elements, and Pb, and to determine the area of their accumulations in the urban zone of the Metropolitan Area of Valle de Aburrá. The study was carried out on 83 samples of topsoil, which were subject to magnetic analyses. The concentration of mayor elements (Al2O3, Fe2O3 y MnO) and Pb was determined by energy dispersive X Ray Fluorescence. A variation of magnetic material in the urban soils was Los parámetros magnéticos como indicadores de contaminación por elementos mayores y plomo en suelos urbanos del Valle de Aburrá, Colombia Alexander Sánchez-Duque1,3, Francisco Bautista1, Rubén Cejudo2,*, Avto Goguitchaichvili2 y Miguel Ángel Cervantes-Solano4 1 Laboratorio Universitario de Geofísica Ambiental (LUGA), Centro de Investigaciones en Geografía Ambiental (CIGA), Universidad Nacional Autónoma de México, Antigua Carretera a Pátzcuaro No. 8701, Col. Ex-Hacienda de San José de la Huerta, C.P. 58190, Morelia, Mich., México. 2 Laboratorio Universitario de Geofísica Ambiental (LUGA), Instituto de Geofísica Unidad Michoacán (IGUM), Universidad Nacional Autónoma de México, Antigua Carretera a Pátzcuaro No. 8701, Col. Ex-Hacienda de San José de la Huerta, C.P. 58190, Morelia, Mich., México. 3 Adscripción actual: Tecnológico Nacional de México, campus Valle de Morelia, km 6.5 Carretera Morelia-Salamanca, C.P. 58100, Morelia, Mich., México. 4 Escuela Nacional de Estudios Superiores Unidad Morelia, Antigua Carretera a Pátzcuaro 8701, C.P. 58190, Morelia, Mich., México. * ruben@igeofisica.unam.mx REVISTA MEXICANA DE CIENCIAS GEOLÓGICAS v. 37, núm. 3, 2020, p. 224-236 I: htt ://dx.doi.org/10.22201/cgeo.20072902e.2020.3.1586 225 Parámetros magnéticos como indicadores de contaminación RMCG | v. 37 | núm. 3 | www.rmcg.unam.mx | DOI: http://dx.doi.org/10.22201/cgeo.20072902e.2020.3.1586 found, which contain a mixture of magnetic minerals of low coercivity or natural magnetite of anthropogenic origin. Particles of superparamagnetic size were detected at medium and low concentrations in soils with low anthropic activity, suggesting a natural origin. On the other hand, by the combination of magnetic parameters and thermomagnetic curves we found high concentrations of magnetic minerals of anthropic origin in the soils. The concentrations of Al2O3 y Fe2O3 are high and similar in the urban soil. Soils from areas of residential and public space use, which have few emission sources of anthropogenic particles, showed low concentration of Pb. On the other hand, soils from areas of industrial and commercial use, with high anthropogenic activity (vehicular traffic), showed high concentration of Pb. Soils from public space areas with low anthropic activity were employ","PeriodicalId":49601,"journal":{"name":"Revista Mexicana De Ciencias Geologicas","volume":"26 1","pages":"224-236"},"PeriodicalIF":0.8,"publicationDate":"2020-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81270231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-24DOI: 10.22201/cgeo.20072902e.2020.3.1585
Emmanuel Olvera-García, Víctor Hugo Garduño-Monroy, Mikhail Ostrooumov, Gerardo Bermejo-Santoyo, Jorge Alejandro Guevara-Alday, Antonio Brogi, Domenico Liotta
In the active San Agustín del Maíz geothermal zone (Michoacán), we identified silica-sinter deposits co-existing with hot springs. Considering the deposition mode, these deposits are separated into fracture-banded and bedded deposits. The first ones are associated with deposition on the channels from the fluids rising to the surface, while the second ones are formed from the geothermal fluids that reached the surface. The bedded deposits showed different types of lithofacies grouped in a range with two endmembers: on the one hand, a pure silica-sinter deposit characterized by high density, glassy aspect and being consolidated. On the other hand, a silty-sandy deposit, that easily disaggregate, presenting impression of plants and lithics. The vitreous deposit is considered geyserite, formed from fluids with temperatures superior to 70 °C, while the silty-sandy deposits are formed from fluids with temperatures below 70 °C and, in some cases, far away from the water source. The geyserite deposits are mineralogically composed only by opal (C and CT), while the silty-sandy deposits are formed by opal in association with other mineralogical phases (linked to sediments). Consequently, we recognized that the lithofacies and the mineralogy of the silica-sinter deposits give information of the temperatures and deposition rates of the parental fluids. This information could be very useful in order to identify setting where existed grater geothermal up flow and temperature (e.g. geiserite Litofacies y mineralogía de los depósitos de sínter de la zona geotérmica de San Agustín del Maíz, Michoacán, México Emmanuel Olvera-García1, 2,*, Víctor Hugo Garduño-Monroy1, Mikhail Ostrooumov1, Gerardo Bermejo-Santoyo1, Jorge Alejandro Guevara-Alday3, Andrea Brogi2 y Domenico Liotta2 1 Universidad Michoacana de San Nicolás de Hidalgo, Instituto de Investigación en Ciencias de la Tierra, Morelia, Michoacán, México. 2 Università degli Studi di Bari, Dipartimento di Scienze della Terra e Geoambientali, Bari, Italia. 3 University of Quebec in Montreal, Department of Earth and Atmospheric Science, Montreal, Canada. * emmanuelog_08@outlook.com REVISTA MEXICANA DE CIENCIAS GEOLÓGICAS v. 37, núm. 3, 2020, p. 212-223 I: htt ://dx.doi.org/10.22201/cgeo.20072902e.2020.3.1585 213 Sínter de la zona geotérmica de San Agustín del Maíz, Michoacán, México RMCG | v. 37 | núm. 3 | www.rmcg.unam.mx | DOI: http://dx.doi.org/10.22201/cgeo.20072902e.2020.3.1585 a) b) Depósitos lacustres y aluviales Mio-Holocénicos Volcanes y productos volcánicos (de ácidos a básicos) del Mioceno tardío al Holoceno Lavas (andesíticas y basálticas) y depósitos ignimbríticos del Mioceno medio y tardío Fallas de normal a oblicua izquierda Falla de lateral a oblicua 3.
在活动的San Agustín del Maíz地热带(Michoacán)，发现了与温泉共生的硅粉烧结矿床。从沉积方式来看，这些矿床可分为裂缝带状和层状矿床。前者与上升到地表的流体在通道上的沉积有关，而后者是由到达地表的地热流体形成的。层状矿床表现为不同类型的岩相组合在一个范围内，具有两个端元:一方面为纯硅烧结矿床，具有高密度、玻璃质、固结的特征;另一方面，粉砂质沉积物，很容易分解，呈现出植物和岩屑的印象。玻璃质沉积物被认为是硅辉石，由温度高于70°C的流体形成，而粉砂质沉积物由温度低于70°C的流体形成，在某些情况下，远离水源。硅辉石矿床在矿物学上仅由蛋白石(C和CT)组成，而粉砂矿床则由蛋白石与其他矿物学相(与沉积物有关)共同形成。因此，我们认识到硅烧结矿床的岩相和矿物学提供了母流体的温度和沉积速率的信息。这些信息可能非常有用的以识别设置,刨丝器存在地热流和温度(例如geiserite Litofacies y mineralogia de los depositos de烧结de la带geotermica德圣奥古斯汀•德尔玉米,米却肯州,墨西哥Emmanuel Olvera-Garcia1 2, *,维克多雨果Garduno-Monroy1,米哈伊尔•Ostrooumov1 Gerardo Bermejo-Santoyo1 Jorge Alejandro Guevara-Alday3 Andrea Brogi2 y Domenico Liotta2 1大学圣尼古拉•米德·德·伊达尔戈,Investigación拉地拉科学研究所，莫雷利亚，Michoacán，墨西哥。2巴西巴里大学地球环境科学学院，意大利巴里。3加拿大蒙特利尔魁北克大学地球与大气科学系，加拿大蒙特利尔。* emmanuelog_08@outlook.com墨西哥科学研究GEOLÓGICAS v. 37, núm。3, 2020, p. 212-223 [j]: http://dx.doi.org/10.22201/cgeo.20072902e.2020.3.1585 213 Sínter de la zona geot)， Maíz, Michoacán, m - - - - - RMCG | v. 37 | núm。3 | | DOI: www.rmcg.unam.mx http://dx.doi.org/10.22201/cgeo.20072902e.2020.3.1585) b) Depositos lacustres y aluviales Mio-Holocenicos volcan y或volcanicos(类basicos) del Mioceno tardio al Holoceno熔岩(andesiticas y basalticas) y Depositos ignimbriticos del Mioceno五分镍币y tardio法拉德正常oblicua izquierda法拉德横向oblicua 3。
{"title":"Litofacies y mineralogía de los depósitos de sínter de la zona geotérmica de San Agustín del Maíz, Michoacán, México","authors":"Emmanuel Olvera-García, Víctor Hugo Garduño-Monroy, Mikhail Ostrooumov, Gerardo Bermejo-Santoyo, Jorge Alejandro Guevara-Alday, Antonio Brogi, Domenico Liotta","doi":"10.22201/cgeo.20072902e.2020.3.1585","DOIUrl":"https://doi.org/10.22201/cgeo.20072902e.2020.3.1585","url":null,"abstract":"In the active San Agustín del Maíz geothermal zone (Michoacán), we identified silica-sinter deposits co-existing with hot springs. Considering the deposition mode, these deposits are separated into fracture-banded and bedded deposits. The first ones are associated with deposition on the channels from the fluids rising to the surface, while the second ones are formed from the geothermal fluids that reached the surface. The bedded deposits showed different types of lithofacies grouped in a range with two endmembers: on the one hand, a pure silica-sinter deposit characterized by high density, glassy aspect and being consolidated. On the other hand, a silty-sandy deposit, that easily disaggregate, presenting impression of plants and lithics. The vitreous deposit is considered geyserite, formed from fluids with temperatures superior to 70 °C, while the silty-sandy deposits are formed from fluids with temperatures below 70 °C and, in some cases, far away from the water source. The geyserite deposits are mineralogically composed only by opal (C and CT), while the silty-sandy deposits are formed by opal in association with other mineralogical phases (linked to sediments). Consequently, we recognized that the lithofacies and the mineralogy of the silica-sinter deposits give information of the temperatures and deposition rates of the parental fluids. This information could be very useful in order to identify setting where existed grater geothermal up flow and temperature (e.g. geiserite Litofacies y mineralogía de los depósitos de sínter de la zona geotérmica de San Agustín del Maíz, Michoacán, México Emmanuel Olvera-García1, 2,*, Víctor Hugo Garduño-Monroy1, Mikhail Ostrooumov1, Gerardo Bermejo-Santoyo1, Jorge Alejandro Guevara-Alday3, Andrea Brogi2 y Domenico Liotta2 1 Universidad Michoacana de San Nicolás de Hidalgo, Instituto de Investigación en Ciencias de la Tierra, Morelia, Michoacán, México. 2 Università degli Studi di Bari, Dipartimento di Scienze della Terra e Geoambientali, Bari, Italia. 3 University of Quebec in Montreal, Department of Earth and Atmospheric Science, Montreal, Canada. * emmanuelog_08@outlook.com REVISTA MEXICANA DE CIENCIAS GEOLÓGICAS v. 37, núm. 3, 2020, p. 212-223 I: htt ://dx.doi.org/10.22201/cgeo.20072902e.2020.3.1585 213 Sínter de la zona geotérmica de San Agustín del Maíz, Michoacán, México RMCG | v. 37 | núm. 3 | www.rmcg.unam.mx | DOI: http://dx.doi.org/10.22201/cgeo.20072902e.2020.3.1585 a) b) Depósitos lacustres y aluviales Mio-Holocénicos Volcanes y productos volcánicos (de ácidos a básicos) del Mioceno tardío al Holoceno Lavas (andesíticas y basálticas) y depósitos ignimbríticos del Mioceno medio y tardío Fallas de normal a oblicua izquierda Falla de lateral a oblicua 3.","PeriodicalId":49601,"journal":{"name":"Revista Mexicana De Ciencias Geologicas","volume":"15 1","pages":"212-223"},"PeriodicalIF":0.8,"publicationDate":"2020-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84413167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-04DOI: 10.22201/cgeo.20072902e.2020.3.1576
Edgar Juárez-Arriaga, Gustavo Murillo-Muñetón
The Olinalá Formation is a marine-continental Permian sedimentary succession of ~860 m thick, which is exceptionally exposed in the northeast of the Guerrero state, in southern Mexico. The depositional architecture of this sedimentary succession indicates a mixed carbonatesiliciclastic homoclinal ramp system. The U-Pb ages of detrital zircon grains set from two basal sandstones of the Olinalá Formation yielded a weighted mean maximum deposit age of 268±5 Ma, which agrees with a Wordian biostratigraphic age based on ammonoids collected at its base. Wide continental siliciclastic facies diversity was identified in this sedimentary succession that represents a prominent fluvial incision valley of 130 m depth, at least. Instead, the siliciclastic and carbonate marine facies indicate a ramp system developed in warm waters and normal salinity conditions. The superposition of different environments in the Olinalá Formation through time allows us to deduce sea-level changes of a different magnitude, which partly controlled the sedimentary evolution of this unit.
{"title":"Arquitectura estratigráfica, ambientes de depósito y geocronología de la Formación Olinalá (Pérmico tardío), noreste de Guerrero, México","authors":"Edgar Juárez-Arriaga, Gustavo Murillo-Muñetón","doi":"10.22201/cgeo.20072902e.2020.3.1576","DOIUrl":"https://doi.org/10.22201/cgeo.20072902e.2020.3.1576","url":null,"abstract":"The Olinalá Formation is a marine-continental Permian sedimentary succession of ~860 m thick, which is exceptionally exposed in the northeast of the Guerrero state, in southern Mexico. The depositional architecture of this sedimentary succession indicates a mixed carbonatesiliciclastic homoclinal ramp system. The U-Pb ages of detrital zircon grains set from two basal sandstones of the Olinalá Formation yielded a weighted mean maximum deposit age of 268±5 Ma, which agrees with a Wordian biostratigraphic age based on ammonoids collected at its base. Wide continental siliciclastic facies diversity was identified in this sedimentary succession that represents a prominent fluvial incision valley of 130 m depth, at least. Instead, the siliciclastic and carbonate marine facies indicate a ramp system developed in warm waters and normal salinity conditions. The superposition of different environments in the Olinalá Formation through time allows us to deduce sea-level changes of a different magnitude, which partly controlled the sedimentary evolution of this unit.","PeriodicalId":49601,"journal":{"name":"Revista Mexicana De Ciencias Geologicas","volume":"20 1","pages":"179-196"},"PeriodicalIF":0.8,"publicationDate":"2020-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75503552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-04DOI: 10.22201/cgeo.20072902e.2020.3.1581
Gerardo Carbot-Chanona, G. Rivera-Velázquez, E. Jiménez-Hidalgo, V. Reynoso
RMCG | v. 37 | núm. 3 | www.rmcg.unam.mx | DOI: http://dx.doi.org/10.22201/cgeo.20072902e.2020.3.1581 Carbot-Chanona, G., Rivera-Velázquez, G., Jiménez-Hidalgo, E., Reynoso, V.H., 2020, The fossil record of turtles and tortoises (Testudines) of Mexico, Central America and the Caribbean Islands, with comments on its taxonomy and paleobiogeography: a bibliographic review: Revista Mexicana de Ciencias Geológicas, v. 37, núm. 3, p. 269-283. ABSTRACT
{"title":"The fossil record of turtles and tortoises (Testudines) of Mexico, Central America and the Caribbean Islands, with comments on its taxonomy and paleobiogeography: a bibliographic review","authors":"Gerardo Carbot-Chanona, G. Rivera-Velázquez, E. Jiménez-Hidalgo, V. Reynoso","doi":"10.22201/cgeo.20072902e.2020.3.1581","DOIUrl":"https://doi.org/10.22201/cgeo.20072902e.2020.3.1581","url":null,"abstract":"RMCG | v. 37 | núm. 3 | www.rmcg.unam.mx | DOI: http://dx.doi.org/10.22201/cgeo.20072902e.2020.3.1581 Carbot-Chanona, G., Rivera-Velázquez, G., Jiménez-Hidalgo, E., Reynoso, V.H., 2020, The fossil record of turtles and tortoises (Testudines) of Mexico, Central America and the Caribbean Islands, with comments on its taxonomy and paleobiogeography: a bibliographic review: Revista Mexicana de Ciencias Geológicas, v. 37, núm. 3, p. 269-283. ABSTRACT","PeriodicalId":49601,"journal":{"name":"Revista Mexicana De Ciencias Geologicas","volume":"15 1","pages":"269-283"},"PeriodicalIF":0.8,"publicationDate":"2020-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78570106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-28DOI: 10.22201/cgeo.20072902e.2020.2.1565
G. Zaragoza, Lizeth Caballero-García, L. Capra, Amiel Nieto-Torres
Secondary lahars represent one of the major threats at active or quiescent volcanoes. Therefore, it is important to stablish their frequency, distribution, and triggering mechanism to define hazard-scenarios. In this work, an analysis of a lahar, that occurred on February 4th, 2010 in the Nexpayantla ravine, on northwestern sector of Popocatépetl volcano is presented. A geomorphological and textural analysis coupled with rain data and satellite imagery were used to determine its origin and to delineate inundation areas. This lahar was triggered by a 100 mm/day precipitation and initiated as a stream flow, that transformed into a debris flow, and ended as a stream flow. The transformation from streamflow to debris flow was due to sediment entrainment by laminar erosion and mass wasting processes. In contrast, its subsequent dilution was favored by changes in channel geometry, the high wood content, and the lack of fine sediment. Modelling of this lahar by numerical simulations allowed to calculate a flow depth of up to 1.7 m. Satellite imagery revealed that the deposit observed in the field represents only 68 % of the actual inundation area. Precipitation data indicates a 27-years return period for rains similar in magnitude to the one that triggered this lahar. Further detailed studies of secondary lahars will allow to better constrain hazard-scenarios at Popocatepetl volcano.
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