San Pablo Basalts: an island arc block in the north of the Central Cordillera of Colombia. Petrographic and chemical characterization

The San Pablo Basalts constitute an exotic block of volcanic rocks that crop out next to marine sediments, located in the Northern part of Colombia´s Central Cordillera, between metamorphic blocks of the Cajamarca Complex and intruded by the Antioquia Batholith, Upper Cretaceous in age. The San Pablo Basalts are composed of basalts (spilitic diabases), with intergranular to phiticsubophitic and occasionally porphyritic and variolitic-subophitic textures, similar to the oceanic crust rocks of the Quebradagrande Complex and the San Jose de Urama Diabases. The higher oxides results suggest that the rocks correspond to calc-alkaline, basalts and basaltic andesites, with SiO2 contents between 43.13% and 55.36%, MgO concentration ranges between 5.85% and 9.45% and TiO2 values between 1% and 2%. Multi-element diagrams of rare earth elements and trace elements show a negative Nb anomaly and positive anomalies of Cs, Ba, K and Pb, which suggests an arc environment with an REE trend similar to MORB-type oceanic crust basalts in the less differentiated rocks, but with higher Th values, which relates them to an island arc environment.Los Basaltos de San Pablo son un bloque de rocas volcánicas que afloran junto a sedimentitas marinas, localizadas en el norte de la Cordillera Central de Colombia, entre bloques de rocas metamórfias del Complejo Cajamarca e intruidos por el Batolito Antioqueño de edad Cretácica superior. Los basaltos de San Pablo están constituidos por basaltos (diabasas espilitizadas), con texturas intergranular a ofítica-subofítica y ocasionalmente porfídica y variolítica – subofítica, similares a las rocas de corteza oceánica del Complejo Quebradagrande y las Diabasas de San José de Urama. Los resultados de óxidos de elementos mayores sugieren que corresponden a basaltos y andesitas basálticas calcoalcalinas, con contenidos de SiO2 entre 43,13% y 55,36%, con concentraciones de MgO en el rango entre 5,85% y 9,45% y valores de TiO2 entre 1% y 2%. Los diagramas multielementales de tierras raras y elementos trazas muestran anomalías negativas de Nb y positivas de Cs, Ba, K y Pb, que sugieren un ambiente de arco, con un patrón de REE similar al de basaltos de corteza oceánica de tipo MORB en las rocas menos diferenciadas, pero con valores mayores de Th que los ubican dentro de un ambiente de arco de islas

Quantitative mineral resource assessment of undiscovered porphyry copper resources in South America

A quantitative resource assessment to be published this fall identifies and evaluates 26 tracts in South America where the geology isconsidered permissive for the occurrence of porphyry copper deposits. For each tract, information is provided on: (1) the rationale fordelineating the tract, (2) examples of important deposits in the tract, (3) the rationale for choosing the mineral deposit model used forthe assessment, (4) exploration history, and (5) expected spatial distribution of undiscovered deposits in the tract. The scale used toevaluate geologic information and define tracts is 1:1,000,000. There are about 600 million tonnes of copper in known porphyry copper deposits in South America. This study estimates there areapproximately 720 million tonnes of additional copper in undiscovered porphyry copper deposits, yielding a combined endowment ofabout 1.3 billion tonnes of copper. There are about 69 known porphyry copper deposits using the criteria adopted here to define a well-explored deposit. This study estimates that a mean of about 140 deposits remain to be found. In other words, about twice as manynew deposits might be found as have already been found. Overall, deposit densities in South America are comparable to those in therest of the world but differ in important details that are reflected in mapped distributions of deposits, metal densities, and percentagesof undiscovered deposits in each tract. The deposits in the tracts that include Chuquicamata and El Teniente are significantly larger intonnage and grade and are reported in a separate model that is more representative of their characteristics. The results of theassessment afirm that not all porphyry copper deposits in South America are located in the Andes. Geologic indications support thepresence of undiscovered deposits in Patagonia as well as the Amazon of Brazil. A preliminary 1:4,000,000 map of the 26 tracts will bedisplayed

A preliminary quantitative mineral resource assessment of undiscovered porphyry copper resources in the Andes mountains of South America

Quantitative information on the probable locations and amounts of undiscovered porphyry copper resources of the world is important to international exploration managers, land-use and environmental planners, economists, and policy makers. The U.S. Geological Survey is organizing and facilitating a cooperative assessment, in collaboration with interested geological surveys and geological organizations, of the likely global distribution, quantity, and quality of selected undiscovered nonfuel mineral resources. This report on undiscovered porphyry copper deposits of the Andes Mountains was produced jointly with the geological surveys of Argentina, Chile, Colombia, and Peru, and is a summary of the more extensive report (>300 pages) that will be published soon. Reports on undiscovered copper resources of other regions of the world are being prepared and will be followed by assessments of the global undiscovered resources of platinum-group minerals and potash

Pan-American quantitative mineral resource assessment of copper, molybdenum, gold, and silver in undiscovered porphyry copper deposits in the Andes mountains, South America

Working together, the geological surveys of Argentina, Chile, Colombia, Peru, and the United States used the U. S. Geological Survey three-part mineral resource assessment methodology (Singer, 1993) to delineate the regional locations and make probabilistic estimates of the amounts of copper, molybdenum, silver, and gold in undiscovered porphyry copper deposits in the Andes. Quantitative information on the probable locations and amounts of undiscovered mineral resources of the world is important to exploration managers, land-use and environmental planners, economists, and policy makers

1:4.000.000

Fil: Zappettini, E.O. Servicio Geológico Minero Argentino; Argentina.Fil: Prieto Rincón, G.; ColombiaFil: Amezcua, Natalia; México.Fil: Muñoz Tapia, Santiago; República Dominicana.Fil: Sepúlveda Ospina, Janeth; Colombia.Fil: Celada Arango, Marlos Mario; Colombia.Fil: Jara, David; Costa Rica.Fil: Cazañas Díaz, Xiomara; Cuba.Fil: Torres Zafra, Jorge Luis; Cuba.Fil: Cobiella Reguera, Jorge Luis; Cuba.Fil: Zurcher, Lukas; Estados Unidos de América.Fil: Orris, Greta; Estados Unidos de América.Fil: Gray, Floyd; Estados Unidos de América.Fil: Maldonado Díaz, Carolina; Guatemala.Fil: Rodriguez, Noé; Honduras.Fil: Mérida Montiel, Ramón; México.Fil: Zarruk, Carlos; Nicaragua.La Asociación de Servicios Geológicos y Mineros de Iberoamérica (ASGMI), bajo los auspicios de la Comisión de la Carta Geológica del Mundo (CCGM) preparó la primera versión del Mapa Metalogénico de América Central y el Caribe. La coordinación general estuvo a cargo del Servicio Geológico Minero Argentino (SEGEMAR), con tres coordinaciones regionales: América Central a cargo del Servicio Geológico Mexicano (SGM), las islas del Caribe a cargo del Servicio Geológico Nacional de la República Dominicana y el norte de América del Sur a cargo del Servicio Geológico Colombiano. Participaron además los Servicios Geológicos, Direcciones de Minería u organismos equivalentes de los países involucrados, que designaron Coordinadores Nacionales. El proyecto fue presentado y aprobado en ocasión de la Asamblea de ASGMI realizada en La Habana (Cuba) en 2017. Posteriormente fue presentado ante la Comisión de la Carta Geológica del Mundo (CCGM) en París en 2018. Los objetivos, criterios metodológicos y cronograma de trabajo fueron así establecidos. En los años 2018 y 2019 se realizaron dos reuniones de los participantes, una en Santo Domingo, República Dominicana, y otra en Tegucigalpa, Honduras. Los avances del mapa fueron presentados durante la Reunión Santo Domingo de 2018 y en ocasión del XV Simposio IAGOD, celebrado en Salta (Argentina) ese mismo año. El mapa fue generado digitalmente a partir del Mapa Estructural del Caribe (Bouysse et al., 2020), provisto por la Comisión de la Carta Geológica del Mundo, realizándose una actualización de la información geológica, a partir de la bibliografía citada en el texto. Los polígonos fueron reclasifi cados y reagrupados en orden a defi nir unidades tectonoestratigráfi cas y mejor refl ejar la metalogénesis de la región. El proyecto en SIG creado es también mostrado en la página WEB de ASGMI (www.asgmi.org.es) con el fi n de facilitar la difusión de los datos del mapa creado. Su formato digital y su disponibilidad en la WEB aseguran un fácil acceso para actualizar la información y hacerlo accesible a los usuarios

Basaltos de San Pablo: un bloque de un arco de islas en el norte de la cordillera Central de Colombia. Caracterización petrográfica y química

The San Pablo Basalts constitute an exotic block of volcanic rocks that crop out next to marine sediments, located in the Northern part of Colombia´s Central Cordillera, between metamorphic blocks of the Cajamarca Complex and intruded by the Antioquia Batholith, Upper Cretaceous in age. The San Pablo Basalts are composed of basalts (spilitic diabases), with intergranular to phiticsubophitic and occasionally porphyritic and variolitic-subophitic textures, similar to the oceanic crust rocks of the Quebradagrande Complex and the San Jose de Urama Diabases. The higher oxides results suggest that the rocks correspond to calc-alkaline, basalts and basaltic andesites, with SiO2 contents between 43.13% and 55.36%, MgO concentration ranges between 5.85% and 9.45% and TiO2 values between 1% and 2%. Multi-element diagrams of rare earth elements and trace elements show a negative Nb anomaly and positive anomalies of Cs, Ba, K and Pb, which suggests an arc environment with an REE trend similar to MORB-type oceanic crust basalts in the less differentiated rocks, but with higher Th values, which relates them to an island arc environment.Los Basaltos de San Pablo son un bloque de rocas volcánicas que afloran junto a sedimentitas marinas, localizadas en el norte de la Cordillera Central de Colombia, entre bloques de rocas metamórfias del Complejo Cajamarca e intruidos por el Batolito Antioqueño de edad Cretácica superior. Los basaltos de San Pablo están constituidos por basaltos (diabasas espilitizadas), con texturas intergranular a ofítica-subofítica y ocasionalmente porfídica y variolítica – subofítica, similares a las rocas de corteza oceánica del Complejo Quebradagrande y las Diabasas de San José de Urama. Los resultados de óxidos de elementos mayores sugieren que corresponden a basaltos y andesitas basálticas calcoalcalinas, con contenidos de SiO2 entre 43,13% y 55,36%, con concentraciones de MgO en el rango entre 5,85% y 9,45% y valores de TiO2 entre 1% y 2%. Los diagramas multielementales de tierras raras y elementos trazas muestran anomalías negativas de Nb y positivas de Cs, Ba, K y Pb, que sugieren un ambiente de arco, con un patrón de REE similar al de basaltos de corteza oceánica de tipo MORB en las rocas menos diferenciadas, pero con valores mayores de Th que los ubican dentro de un ambiente de arco de islas

Evaluación de recursos y reservas de carbón en el área de El Hoyo-Limoncito, municipios de El Tambo y Patía (Cauca, Colombia)

The surface geological exploration complemented with core drilling, carried out during 1998 by INGEOMINAS on the municipalities of El Tambo and Patia, as well as the data obtained during the exploration in 1994, have permitted to collect the information needed for the first evaluation of coal resources on the area of El Hoyo - Quilcace, El Vergel y Yeguas-Limoncito.Using the concepts, classification criteria and dispositions of the Classification of Coal Resources and Reserves System by ECOCARBON, were calculated and ordinate on categories the coal volumes. The total figures of the basic reserves and resources, calculated on the whole referred sectors are: 1.967.061 Tons Measured reserves, 5.965.533 Tons Indicated reserves, 12.268.418 Tons Inferred reserves, 4.415.939 Tons Measured resources, 13.099.071 Tons Indicated resources, 18.455.711 Tons Inferred resources and run out of reserves do not exist.The global results of coal quality on the area of El Hoyo - Limoncito, indicate a calorific power between 6858 and 7354 cal/gr. on moisture base free of mineral material; An ash content between 8.12 and 18.04 % on dry base and a total sulfur content between 0.89 and 2.32 % on dry base; all of this associated with ASTM classification, as bituminous coals high in volátiles C and D, permit to assign a technological use as thermic Coals.La exploración geológica de superficie complementada con perforaciones corazonadas, llevada a cabo durante 1998 por Ingeominas en los municipios de El Tambo y Patía, en el departamento del Cauca, cuyos resultados se añaden a los obtenidos con la exploración de 1994, han permitido acopiar una información que conduce a una primera evaluación de los recursos carboníferos presentes en los Sectores de El Hoyo-Quilcacé, El Vergel y Yeguas-Limoncito pertenecientes al área Carbonífera de El Tambo-Patía. Con base en los conceptos, criterios de clasificación y disposiciones del Sistema de Clasificación de Recursos y Reservas de Carbón de ECOCARBÓN, se calcularon y ordenaron en categorías los volúmenes de carbón. Las cifras totales de las reservas básicas y recursos, calculados en la totalidad de los sectores referidos, ascienden a: 1.967.061 toneladas en la categoría de reservas medidas; 5.965.533 toneladas en la categoría de reservas indicadas; 12.268.418 toneladas en la categoría de reservas inferidas, 4.415.939 toneladas en la categoría de recursos medidos; 13.099.071 toneladas en la categoría de recursos indicados; 18.455.711 toneladas en la categoría de recursos inferidos. No existen reservas agotadas.Los resultados globales de la calidad de los carbones del área El Hoyo-Limoncito, indican un poder calorífico entre 6858 y 7354 cal/gr en base húmeda libre de material mineral; un contenido de cenizas en el rango entre 8.12 y 18.04% en base seca y un contenido de azufre total entre 0.89 y 2.32% en base seca, que en asocio con la clasificación por rango de la ASTM, como carbones bituminosos altos en volátiles C y D, permiten asignarles un uso tecnológico como carbones térmicos

Quantitative Mineral Resource Assessment of Copper, Molybdenum, Gold, and Silver in Undiscovered Porphyry Copper Deposits in the Andes Mountains of South America

Quantitative information on the general locations and amounts of undiscovered porphyry copperresources of the world is important to exploration managers, land-use and environmental planners, economists, and policymakers. This publication contains the results of probabilistic estimates of theamounts of copper (Cu), molybdenum (Mo), silver (Ag), and gold (Au) in undiscovered porphyry copperdeposits in the Andes Mountains of South America. The methodology used to make these estimates is called the "Three-Part Form.” It was developed to explicitly express estimates of undiscovered resourcesand associated uncertainty in a form that allows economic analysis and is useful to decisionmakers. The three-part form of assessment includes: (1) delineation of tracts of land where the geology ispermissive for porphyry copper deposits to form; (2) selection of grade and tonnage models appropriatefor estimating grades and tonnages of the undiscovered porphyry copper deposits in each tract; and (3)estimation of the number of undiscovered porphyry copper deposits in each tract consistent with the gradeand tonnage model. A Monte Carlo simulation computer program (EMINERS) was used to combine theprobability distributions of the estimated number of undiscovered deposits, the grades, and the tonnages ofthe selected model to obtain the probability distributions for undiscovered metals in each tract. Thesedistributions of grades and tonnages then can be used to conduct economic evaluations of undiscovered resources in a format usable by decisionmakers. Economic evaluations are not part of this report. The results of this assessment are presented in two principal parts. The first part identifies 26 regional tracts of land where the geology is permissive for the occurrence of undiscovered porphyrycopper deposits of Phanerozoic age to a depth of 1 km below the Earth’s surface. These tracts are believed to contain most of South America's undiscovered resources of copper. The second part presentsprobabilistic estimates of the amounts of copper, molybdenum, gold, and silver in undiscovered porphyry copper deposits in each tract. The study also provides tables showing the location, tract number, and age (if available) of discovered deposits and prospects. For each of the 26 permissive tracts delineated in thisstudy, summary information is provided on: (1) the rationale for delineating the tract; (2) the rational for choosing the mineral deposit model used to assess the tract; (3) discovered deposits and prospects; (4) exploration history; and (5) the distribution of undiscovered deposits in the tract. The scale used toevaluate geologic information and draw tracts is 1:1,000,000. There are 69 known porphyry copper deposits in the Andes using criteria adopted herein to definea deposit. This assessment estimates that about 145 undiscovered deposits remain. In other words, abouttwice as many new deposits might be found as have already been found. Not only have large quantities ofcopper been discovered, but also even larger quantities of undiscovered copper remain. About 590 million metric tons of copper have been discovered. About 190 million tons of this amount are in 57 deposits of the general porphyry copper type whereas nearly 400 million metric tons are in an additional 12 giantdeposits. This study estimates that there are approximately 750 million metric tons of copper in undiscovered deposits of these two types in the Andes. This undiscovered copper resource is the sum ofthe mean estimated copper in each of 26 tracts. About 470 million metric tons of this copper are estimated to occur in 137 undiscovered deposits in 24 tracts of the general porphyry copper type, plus another 280 million metric tons estimated in 8 undiscovered deposits in 2 tracts of the giant porphyry copper type. Thetotal discovered, mined, and undiscovered copper amounts to an endowment, or grand total, of about 1.3 billion metric tons. The estimates suggest there may be almost 1.3 times as much copper to be found in porphyry copper deposits of the Andes as has already been found. In addition to copper, the undiscovered deposits also contain large estimated amounts ofmolybdenum (20,000,000 metric tons), gold (13,000 tons), and silver (250,000 tons). The estimated undiscovered copper is equivalent to about 80 percent of the world reserve base; molybdenum, 105 percent; gold, 14 percent; and silver, 44 percent. Not all of these undiscovered mineral resources are likely to be available for discovery anddevelopment. Commonly, a significant amount of land delineated as permissive or even favorable for theoccurrence of undiscovered mineral deposits is not available for mineral exploration, discovery, and development because it consists of urban areas, transportation corridors, forest and wildlife preserves,sensitive ecosystems, protected biodiversity areas, sensitive and threatened surface and groundwatersupplies, wilderness areas, national parks, private land where mining is not desired, and many other reasons. Global inventory and analysis are needed of such restrictions and their probable impact on futuremineral supply and costs. The porphyry copper resources reported herein are not evenly distributed throughout the Andesregion. The Chuquicamata tract (SA10a,bPC) and the El Teniente tract (SA14bPC) are remarkable incontaining exceptionally large deposits of discovered, mined, and estimated undiscovered copper that do not conform to grade and tonnage characteristics of the general porphyry copper model appropriate forother Andean tracts. The deposits in these two tracts being significantly larger in tonnage and higher in grade necessitated a new giant model that is more representative of their characteristics. The greatest premining endowment of copper is in Eocene-Oligocene tract SA10a,bPC with about 460 million metric tons, followed by late Miocene-early Pliocene tract SA14bPC with about 220 million metric tons. Thenext largest endowments are in tract SA8PC (a Paleocene–Eocene tract of Chile-southern Peru) containing an endowment of about 98 million metric tons and in tract SA6PC (the middle–late Miocene tract of Peru-Ecuador) with an endowment of about 96 million metric tons. The undiscovered copper remaining to be found in these four tracts is estimated to be: tract SA10a,bPC, 210 million metric tons; tract SA14bPC, 69 million; tract SA6PC, 49 million; and tract SA8PC, 43 million. Density of estimated undiscovered metal in tracts was examined as mean metric tons of metal per km2 in undiscovered deposits. Giant tracts SA10a,bPC and SA14bPC have the highest copper densitieswith about 8,200 and 7,400 metric tons per km2, respectively. The next richest tracts, with just over 2,000 metric tons per km2, are tracts SA12PC and SA14dPC. About 90 percent of the total discovered and estimated undiscovered copper resources in Andean porphyry copper deposits is of Cenozoic age; the remainder is Cretaceous (4%), Jurassic (5%), andPermian (2%) in age. The Cenozoic resources are in tracts with host rock ages of Eocene–Oligocene (39%), Miocene–Pliocene (29%), Paleocene–Eocene (12%), and Miocene (11%). The Eocene–Oligocene and Miocene–Pliocene tracts are dominated by giant tracts SA10a,bPC (includes Chuquicamata deposit) and SA14bPC (includes El Teniente deposit). There appear to have been three approximately 16-million-year-long episodes of porphyry copper deposit formation in the Andes during Cenozoic time: Paleocene–early Eocene, late Eocene–early Oligocene; and middle Miocene–early Pliocene. These three episodes appear to be separated by twointervening quiescent periods of 5 to 9 million years duration in the middle Eocene (44-49 Ma) and late Oligocene–early Miocene (20-29 Ma). These two periods correspond to times of change in Pacific plateboundaries, geometries, and directions and rates of spreading and convergence. There are variations in the geographic trends of magmatic arcs in the southern Andes. Tract SA14cPC, for example, follows a transverse SE-trending band of late Miocene–early Pliocene volcanicrocks and associated upper Miocene porphyry copper deposits, prospects, and other areas of altered and mineralized rocks. The parent magmatic source is approximately perpendicular to the grain of the fault-controlled outcrops of metamorphic basement rocks that reflect the surface geology and could becontrolled by a tear fault in a subducted plate. Southeast-trending tract SA19PC, which extends from theAndes south southeasterly across the Patagonia of Argentina to the Atlantic Ocean, and contains the Bajo de la Leona prospect, also shows that Mesozoic porphyry copper ore-forming processes occurred outside of the present-day trend of the Andes. The results of this assessment study are likely to spur research and exploration activities in theAndes and adjacent regions, which in turn will enable the evaluation and update of regional assessmentsof porphyry copper resources in the future

Epigenetic deregulation of protocadherin PCDHGC3 in pheochromocytomas/paragangliomas associated with SDHB mutations

[Context]: SDHB mutations are found in an increasing number of neoplasms, most notably in paragangliomas and pheochromocytomas (PPGLs). SDHB-PPGLs are slow-growing tumors, but ∼50% of them may develop metastasis. The molecular basis of metastasis in these tumors is a long-standing and unresolved problem. Thus, a better understanding of the biology of metastasis is needed. [Objective]: This study aimed to identify gene methylation changes relevant for metastatic SDHB-PPGLs. DESIGN: We performed genome-wide profiling of DNA methylation in diverse clinical and genetic PPGL subtypes, and validated protocadherin γ-C3 (PCDHGC3) gene promoter methylation in metastatic SDHB-PPGLs. [Results]: We define an epigenetic landscape specific for metastatic SDHB-PPGLs. DNA methylation levels were found significantly higher in metastatic SDHB-PPGLs than in SDHB-PPGLs without metastases. One such change included long-range de novo methylation of the PCDHA, PCDHB, and PCDHG gene clusters. High levels of PCDHGC3 promoter methylation were validated in primary metastatic SDHB-PPGLs, it was found amplified in the corresponding metastases, and it was significantly correlated with PCDHGC3 reduced expression. Interestingly, this epigenetic alteration could be detected in primary tumors that developed metastasis several years later. We also show that PCDHGC3 down regulation engages metastasis-initiating capabilities by promoting cell proliferation, migration, and invasion. [Conclusions]: Our data provide a map of the DNA methylome episignature specific to an SDHB-mutated cancer and establish PCDHGC3 as a putative suppressor gene and a potential biomarker to identify patients with SDHB-mutated cancer at high risk of metastasis who might benefit from future targeted therapies.This work was supported by the Spanish Group of Neuroendocrine Tumors (GETNE), Fundación para el Fomento en Asturias de la Investigación Científica Aplicada y la Tecnología (GRUPIN14-003), Instituto de Salud Carlos III (PI17/01901), and by European Regional Development funds (FEDER, CIBERONC)