Boletín Geológico最新文献

{"title":"Magnetic fabric of deformed Quaternary sediments: contributions to the understanding of the neotectonic activity in the surroundings of the Aburrá Valley, Central Cordillera, Colombia","authors":"Santiago Noriega Londoño, Duván Jaraba, María Paula Ruiz, M. I. Marín-Cerón, S. Restrepo-Moreno","doi":"10.32685/0120-1425/bol.geol.49.1.2022.634","DOIUrl":"https://doi.org/10.32685/0120-1425/bol.geol.49.1.2022.634","url":null,"abstract":"The origin of the Aburrá Valley (AV) is proposed as a set of coalescent tectonic subbasins located along the northern  portion of the Central Cordillera of Colombia, the Northern  Andes of Colombia. The Itagüí, Medellín, Bello, and Barbosa  subbasins have developed between the Romeral Shear Zone (RSZ) and the Antioqueño Batholith starting in the Late  Cenozoic. The aim of this study is to contribute to the  understanding of the AV neotectonic framework using the  anisotropy of magnetic susceptibility (AMS) and structural  analysis. For this, we measure the magnetic fabric ellipsoid  shape of faulted sediments and compare them with the geometry and kinematics of fault planes to determine their  relationship with the present-day stress field and the  regional fault architecture. The principal directions of the  elongation axes along the La Brizuela and Yarumalito sites  were NE-SW, following the magnetic lineation trend and  marking a normal displacement with a dextral component.  A marked NW-SE magnetic cleavage was found for the La  Caimana site along a strike-slip tectonic setting. Holocene  ruptures of the principal displacement zone (i.e., the RSZ)  and their surroundings, may indicate normal faulting, with  fault bends and steps over basins controlled primarily by R´ and P structures. Moreover, the active faults located to the  east of the AV indicate post Plio-Pleistocene deformations  with normal faulting through 90/80 to 150/70 antithetic  faults. This work identifies the AMS technique as a powerful  tool, for understanding the neotectonic framework along  urban and surrounding areas. ","PeriodicalId":124675,"journal":{"name":"Boletín Geológico","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129649041","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}

{"title":"Region-scale estimation of potential groundwater recharge in soft and hard rock formations through a distributed water balance in the area of influence of the tropical dry forest in the Cauca River canyon, Antioquia, Colombia","authors":"Breiner Dan Bastidas, Juliana Ossa, Cristina Martínez, María Alejandra Vela, T. Betancur, Arbei Osorio","doi":"10.32685/0120-1425/bol.geol.49.1.2022.625","DOIUrl":"https://doi.org/10.32685/0120-1425/bol.geol.49.1.2022.625","url":null,"abstract":"La recarga potencial de aguas subterráneas se estima comúnmente mediante balances hídricos por unidad  hidrogeológica. La mayoría de los estudios en Antioquia  (Colombia) se refieren a la recarga en depósitos aluviales o  unidades de rocas sedimentarias. En 2020 se inició la  evaluación del potencial hidrogeológico en zona de  influencia del bosque seco tropical en el cañón del río  Cauca, en jurisdicción de Corantioquia, incluyendo estimaciones regionales de recarga potencial por  precipitación. La estimación de la recarga se realizó a través  de un modelo distribuido de balance de humedad en el  suelo a escala diaria, en el que se incorporó de manera  eficiente la variabilidad espaciotemporal de las condiciones  meteorológicas de la región, así como la variabilidad  espacial de las propiedades de superficie, como suelos,  coberturas terrestres y topografía. Entre 2013 y 2020 se estimaron tasas de recarga anual que  varían espacialmente entre 5 mm/año y 2000 mm/año, lo  que representa entre 0,4 % y 45 % de la precipitación, con promedio espacial y multianual de 342 mm/año (17 % de la  precipitación). Los acuíferos de la Formación Penderisco se  caracterizan por recarga potencial media anual entre 284  mm (al noroeste) y 756 mm (al suroeste); los acuíferos de la  Formación Combia presentan tasas de recarga media anual  de 456 mm; el Acuífero Libre del Occidente Antioqueño y otros asociados a depósitos cuaternarios registran tasas de  recarga media anual de 36 mm. El comportamiento evidenciado de recarga en la zona favorece la condición de  flujos regionales entre unidades hidrogeológicas y ratifica el potencial hidrogeológico significativo de diversas unidades de rocas duras fracturadas.","PeriodicalId":124675,"journal":{"name":"Boletín Geológico","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131944940","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}

{"title":"Interpretation of Palaeozoic geoforms with the use of seismic attributes in a region of the Eastern Plains, Colombia","authors":"Laura Carolina Esquivel, Fanny Villamizar, I. Molina","doi":"10.32685/0120-1425/bol.geol.49.1.2022.557","DOIUrl":"https://doi.org/10.32685/0120-1425/bol.geol.49.1.2022.557","url":null,"abstract":"This study focused on producing maps of Palaeozoic geoforms in the subsoil of a region of the Eastern  Planes basin, Colombia. The results provide novel Palaeozoic  information for the study area suggesting a  possible shallow marine depositional environment in the  Ordovician and a slightly deeper shallow marine environment in the Cambrian. This information was  obtained from the analysis of both seism stratigraphic  sequences and gamma ray well logs and from the seismic  interpretation of possible geological structures at depth,  using a seismic cube, four 2D seismic lines and four wells.  The results were complemented with the application of the  seismic attributes of coherence, variance, RMS amplitude  and spectral decomposition to highlight geological characteristics such as structures and lithology. The  information was integrated and analyzed to generate maps  of geoforms corresponding to the Middle Ordovician,  Lower Ordovician and Cambrian sequences.","PeriodicalId":124675,"journal":{"name":"Boletín Geológico","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114379093","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}

{"title":"Determination of a potentially optimal zone to perform hydraulic fracturing work, Upper Magdalena Valley basin, Colombia","authors":"Carlos Fabián Sánchez, I. Molina, Gabriel Ángel Molina","doi":"10.32685/0120-1425/bol.geol.49.1.2022.519","DOIUrl":"https://doi.org/10.32685/0120-1425/bol.geol.49.1.2022.519","url":null,"abstract":"The present study was carried out for an oil field located in the upper Magdalena Valley basin, Colombia, in which successful hydraulic fracturing was carried out in a well, which we denote fractured. The main objective is to replicate this technique in an existing well in the same field. For this work, electrical logs from twelve  wells, including the fractured well, were analyzed to obtain a correlation between the area of interest, located  in the Monserrate Formation, and each of the wells under study. By using gamma ray, resistivity, neutron and  density logs, the petrophysical properties were calculated to determine the shale volume, effective porosity,  total porosity, water saturation and permeability in each well. Additionally, the production history of each of  the wells and the calculations described above were used to suggest a new site where hydraulic fracturing  could also be successful. Two candidates were proposed in this study, one based on the similarity of its  petrophysical properties, and another based on the consideration of additional production data. Notably, this well stimulation technique has global importance and has produced positive impacts on increased oil  production where it has been implemented. The purpose of this study is to provide technical support for the  decision to replicate this procedure in a new area of the field. ","PeriodicalId":124675,"journal":{"name":"Boletín Geológico","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125827221","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}

{"title":"Petrographic, chemical and geochronological characteristics of the Onzaga Metarhyolite and its correlation with Ordovician magmatic events in the northern Andes, Colombia","authors":"R. García","doi":"10.32685/0120-1425/bol.geol.49.1.2022.571","DOIUrl":"https://doi.org/10.32685/0120-1425/bol.geol.49.1.2022.571","url":null,"abstract":"The macroscopic, microscopic, and chemical characteristics as well as crystallization age of the Onzaga Metarhyolite unit are described. The spatiotemporal relationships among the magmatic events that occurred during the Ordovician in the Santander, La Floresta and Quetame massifs and in the Mérida Mountain range are analyzed. Additionally, a correlation is made with plutonic bodies that have crystallization ages within this same period of time. \u0000The Onzaga Metarhyolite outcrops in the Santander massif in the surroundings of the municipality of Onzaga-Santander, with an approximate area of 155 km2; it is composed of metavolcanic rocks that are chemically classified as rhyolites, which were affected by metamorphism in green schist facies to low amphibolite. The metarhyolites are composed of quartz porphyroclasts, plagioclase and alkali feldspar, and some retain the textures and relict forms of the phenocrysts, which are found within a microcrystalline matrix, with local development of quartz mosaics and oriented sheets of white mica and biotite. \u0000The rocks of the Onzaga Metarhyolite have high contents of SiO2 (76.9% to 79.3%), K2O (4.03% to 5.66%) and Al2O3 (11.5% to 14.3%) and low contents of Fe2O3, TiO 2, CaO, MnO and MgO. The rocks have alkali values (Na2O + K2O) between 5.3% and 7.9% and K2O/Na2O> 2. They are classified within the calc-alkaline rocks high in K, peraluminous, and related to magmas that generate type S granites. In the multielement diagrams, Nb has a weak negative anomaly, as does Zr, while the negative anomalies of Ti and Sr are pronounced. Higher values of lithophilic elements of high ionic radius (LILE) Cs, Ba and Th indicate a continental crust affinity. The Eu/Eu * values are low, between 0.12 and 0.74. The normalized values of (La/Yb) N vary between 4 and 24.4, (La/Sm) N varies between 2.2 and 2.5, and (Eu/Yb) N varies between 0.2 and 2.1. \u0000Two samples of Onzaga Metarhyolite were analyzed by the LA-ICP–MS U-Pb method in zircon. The results analysis indicates a crystallization age that varies between 450.9 ± 2.5 Ma and 449.9 ± 5.9 Ma, with a second population between 475.9 ± 5.4 Ma and 469.8 ± 4.0; these ages are interpreted as magmatic zircons inherited from a lower to middle Ordovician igneous event. The zircons have xenocrysts and inherited nuclei of 555 ± 11 Ma and 565.7 ± 9 Ma and populations of 617 ± 16 Ma (n = 3) and 644.5 ± 6.5 (n = 3), respectively, and three inheritances between 1071 ± 48 Ma and 1171 ± 37 Ma.","PeriodicalId":124675,"journal":{"name":"Boletín Geológico","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131924085","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}

{"title":"Regional integration and 3D modeling of airborne geophysical data: Map of Geophysical Anomalies of Colombia for mineral resources, 2020 version","authors":"M. Puentes, A. Robayo, I. Moyano, E. Henrique, Marcela Lara, Hernán Arias, D. Ospina, Ó. Rojas, Ernesto Gómez, S. Torrado, Gloria Prieto Rincón","doi":"10.32685/0120-1425/bol.geol.48.spl.1.2021.586","DOIUrl":"https://doi.org/10.32685/0120-1425/bol.geol.48.spl.1.2021.586","url":null,"abstract":"The Map of Geophysical Anomalies of Colombia for mineral resources, MAGC 2020 version compiles the geophysical information acquired, processed and interpreted by the Servicio Geológico Colombiano (SGC) since 2013. This information was collected via airborne platforms (aircrafts) using magnetometry and gamma spectrometry. This version covers approximately 547 960 km2 of the national territory in the Andean (North and Central), Eastern (Eastern Plains and Amazon) and Caribbean zones (Perijá mountain range). This information consists of 17 blocks of geoscientific interest, covered by flight lines separated by 500 and 1000m, for a total of more than 907 566 linear km of airborne information, acquired at a nominal altitude of 100 m above the ground, with a sampling resolution that was not previously available at this scale and coverage. This document presents the methodology for compiling, processing and representing the thematic coverage included in MAGC 2020: Map of Total field magnetic anomaly (TFMA), Map of the analytic signal (AS) and radiometric ternary map of the distribution of the relative concentrations of uranium, thorium and potassium. Furthermore, the work identifies 1079 magnetometric anomalies of interest, which were subsequently analyzed and modeled in the Map of magnetic sources modeled from magnetization vector inversion, which contains a total of 1297 magnetic bodies interpreted from these anomalies. Integration of available geological and metallogenic information with each of these bodies allow the suggestion of possible geological sources and possible exploration targets. The objectives of this study were to generate and integrate geophysical information to identify new areas of interest with regards to potential mineral resources, and to generate new geoscientific knowledge about Colombia for land-use planning.","PeriodicalId":124675,"journal":{"name":"Boletín Geológico","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131100033","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}

{"title":"Geological modeling of a hydrocarbon reservoir in the northeastern Llanos Orientales basin of Colombia","authors":"Laura Juliana Rojas Cárdenas, I. Molina","doi":"10.32685/0120-1425/bol.geol.48.2.2021.518","DOIUrl":"https://doi.org/10.32685/0120-1425/bol.geol.48.2.2021.518","url":null,"abstract":"An hydrocarbon reservoir was characterized via a detailed geologic model, which allowed estimation of the original oil in place. The study characterizes a hydrocarbon reservoir of two fields of unit C7 of the Carbonera Formation within the Llanos Orientales basin of Colombia. This was done using well logs, the structural surface of the regional datum of the area, segments of the Yuca fault and a local fault of the reservoir, the  permeability equation, and J functions of the reservoir provided by the operating company. With this  information, a two-fault model and a grid with 3D cells was created. Each cell was assigned with a value of facies and petrophysical properties: porosity, permeability, and water saturation, to obtain a 3D model of  facies and petrophysical properties. Subsequently, we used the constructed models and oil-water contacts to  calculate the original oil in place for each field. Field 1 has a volume of six million barrels of oil and field 2 has  9 million barrels. ","PeriodicalId":124675,"journal":{"name":"Boletín Geológico","volume":"122 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115512306","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}

{"title":"Analytical solution of CO2 mass flux measurement with Non-Dispersive Infrared sensors for soil in diffusive and advective-diffusive regime: Tool for the continuous and telemetric measurement of volcanic gases in an open chamber","authors":"Nicolás Oliveras","doi":"10.32685/0120-1425/bol.geol.48.2.2021.496","DOIUrl":"https://doi.org/10.32685/0120-1425/bol.geol.48.2.2021.496","url":null,"abstract":"Measuring the carbon dioxide (CO2) mass flux in a volcanic environment is necessary for volcanic monitoring. CO2 mass flux must be measured continuously and telemetrically to get, almost in real-time, a better understanding of the dynamics of the volcanic degassing processes, contributing to the building, together with other monitoring technics, of a volcano behavior model. This study presents two analytical solutions, 1) a simple diffuse solution and 2) an advective-diffusive solution, which both implement NDIR (Non-Dispersive Infrared Emitter) sensor arrays in an open chamber (diffusion chimney) and an exchange chamber (gas interchanger). The first system, for which the gas speed is negligible, despite being basic (with values reflected in the slope of an equation line), introduces mass flux calculations with a single sensor NDIR. For the second system, where the gas speed is part of the equation, another mathematical solution and three measuring points are required, which demands the system to include a se­cond NDIR sensor for the correct mathematical solution of the equations system. In addition, an embedded system can automate the method by calibrating, controlling an agitation fan, and recording temperature, pressure, and mass flux in volcanic soils at the surface. Since this theoretically proposed method needs to be tested, experimental data are expected to validate the measurement of CO2 mass flux, which will be used as a helpful tool for volcanic monitoring.","PeriodicalId":124675,"journal":{"name":"Boletín Geológico","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127065808","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}

{"title":"The role of Rare Earth Elements in the deployment of wind energy in Colombia","authors":"Carlos Andrés Gallego","doi":"10.32685/0120-1425/bol.geol.48.2.2021.552","DOIUrl":"https://doi.org/10.32685/0120-1425/bol.geol.48.2.2021.552","url":null,"abstract":"The deployment of renewable energy technologies will play a crucial role in the global transition to a low-carbon economy and ultimately in the fight against global warming. However, this transition could face important problems because most of those technologies rely on the steady supply of critical minerals. Colombia, thanks to its hydrological resources, has relied on the hydro­power for electricity generation. However, the government has implemented measures to back-up the energy system in draught periods and, consequently, fossil fuels-based plants have increased the market share and with these, CO2 emissions. This study assesses the mineral demand in Colombia in the period 2020-2050 for the rare earth elements embedded in the deployment of wind power technologies in four different climate policy scenarios in order to establish whether they could face geological bott­lenecks that could ultimately hamper the transition to a low-carbon economy. The Gigawatts (GW) of future capacity additions in the energy system are converted into tons of metal using published metal intensities of use and assumptions of Colombia’s technological pathway. Then, the cumulated mineral demand is compared against current mining production rates and geological reserves to establish geological bottlenecks. The results show that the reserves will not pose any threat to its transition. However, when compared to current mining rates, the mineral demand in 2050 could pose a problem for the supply of minerals. Finally, this study gives some policy recommendations that could be used to mitigate these issues, such as substitution, improved circular economy and sound technological choices.","PeriodicalId":124675,"journal":{"name":"Boletín Geológico","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123663050","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}

{"title":"Historical memory of the geology of Antioquia: Emil Grosse and The Carboniferous Tertiary of Antioquia","authors":"Felipe Velásquez Ruiz, Marion Weber Scharff, Verónica Botero Fernández","doi":"10.32685/0120-1425/bol.geol.48.2.2021.570","DOIUrl":"https://doi.org/10.32685/0120-1425/bol.geol.48.2.2021.570","url":null,"abstract":"The Carboniferous Tertiary of Antioquia (TCA), published by Dr. Jakob Emil Grosse in 1926, is one of the most influential scien­tific results of the Ordinance 16 of 1918 of the Honorable Departmental Assembly of Antioquia. The work began with the main objective of quantifying the coal reserves of Antioquia, and showing their surface extension on a scale of 1:50 000, in a region that includes the Arma river to the Puente de Occidente and from the western side of the Cauca River to the Romeral lineament and the plains of Ovejas. As a result, extensive work comprising petrological, structural, and economic geology studies was published in a manuscript published in Spanish and German, plus four attached maps, including coal, gold, silver, kaolin, and carbonate mines, among others. In the present work, the four TCA maps were digitized at a scale of 1:50 000 with Bessel 1841 datum and created a unified file in .kml format, which can be used directly in field trips, via Google Earth on cell phones, tablets, or computers. The metadata associates the information in the TCA with the Servicio Geológico Colombiano for the year 2015. In addition, 480 thin sections were scanned, which were donated by Dr. Grosse to the Escuela Nacional de Minas and today are in the Museum of Geosciences of the Faculty of Mines of the Universidad Nacional de Colombia. The geospatial information contained in each thin section was interpreted and georeferenced, obtaining, as a result, a list with north and west geographic coordinates, in degrees, minutes, and seconds. This unpublished information is available in the supplementary material of this article. Finally, nine field trips were made to the places referenced in 23 photographs of the TCA between 1920 and 1923 to take their current equivalent and thus carry out a multi-temporal analysis of the TCA.","PeriodicalId":124675,"journal":{"name":"Boletín Geológico","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115553761","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}