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The La Cocha-Río Téllez Migmatitic Complex is located on the eastern flank of the Colombian Andes, between the departments of Nariño and Putumayo. It crops out as windows between recent volcanic and fluvio-volcanic deposits. Under the name of La Cocha-Río Téllez Migmatitic Complex, granitoids, quartz-feldspar-moscovite and biotite gneisses, tonalites, mylonitic metatonalites and migmatitic amphibolites of different age and geological environment were grouped. According to our results, in this contribution we propose to stop using the name La Cocha-Río Téllez Migmatitic Complex and henceforth use the formal names of five units that represent different metamorphic and igneous events, formed between the Devonian (?) and Oligocene, which we propose to call as follows: the Sibundoy Gneiss to the unit with metamorphism ages between 365.97 ± 12.8 Ma and 386.78 ± 15.9 Ma, the San Francisco Schists with ages around 163 Ma, the Motilón Granodiorite to the pluton with crystallization ages between 172. 7±1.4 and 152.2 ± 0.31 Ma, the Alisales Tonalite to the pluton with crystallization ages of 32.4 ± 0.58 Ma, and the Tellez River Amphibolites to the unit with metamorphism ages of 80.4 ± 1.5 Ma. [ABSTRACT FROM AUTHOR]

The purpose of this research is to determine the geochemical and mineralogical similarities of both clay sources from the Tena and Archidona cantons and Cosanga archaeological objects recovered from the upper Napo River basin, Cosanga and Quijos valleys. 22 clay samples and 15 archaeological artifacts were used. The geochemical analyses were performed by atomic absorption spectroscopy (AAS) and energy dispersive X-ray (EDX), while the mineralogical analyses were done by X-ray diffraction (XRD), also using scanning electron microscope (SEM) images. The results showed that both the raw material and the objects came from a homogeneous geological environment, confirming the exchange within the study area. [ABSTRACT FROM AUTHOR]

Introduction: The production of charcoal in Cuba, in recent years, has been stimulated due to its prices in the international market and the use of invasive plants for its production. Depending on its quality, a possible use is defined, taking into account its chemical composition. Objective: To evaluate the technical feasibility of improving the quality of a marabou charcoal from a physical treatment with water vapor. Materials and Methods: The characterization of a marabou charcoal was carried out, which was crushed in a hammer mill, analyzing the granulometric distribution. The density and chemical composition of the coal are determined without treatment and after carrying out a physical treatment, for two hours, with steam. Results and Discussion: The characterization resulted in the charcoal meeting international quality requirements. In the untreated coal, the moisture content was 6.4 %, volatile 16.3 %, ash 3.8 %, fixed carbon 73.5 % and the caloric value was 28813.5 kJ/kg. In the case of coal with treatment, the volatile content was 12.9 %, ash 3.3 %, fixed carbon 77.1 %, and caloric value 29508.6 kJ/kg. Conclusions: The physical treatment carried out produces a decrease in the volatile matter content and an increase in the fixed carbon content and caloric value, results that support the possibility of using marabou charcoal in the alloy load of welding consumables for welding recharge. [ABSTRACT FROM AUTHOR]

Limestone rock has long been of great importance economics for society, due to its physicochemical characteristics that allow its use as input for the manufacture of covering, lime, cement, concrete and stuc. At the municipality of Manaure-Cesar, La Tomita sector outcrop limestones interspersed with shales, corresponding to the Lagunita Formation of the Cogollo Group. This research has as its main objective to know the geographical distribution of the Lagunita Formation, the chemical composition of limestones and their potential use as an industrial material. This is done using cartographic, stratigraphic and geochemical (X-ray fluorescence) techniques compared to the guidelines of Colombian Technical Standard (NTC) 5163. This concluded that in the village La Tomita the limestones texturally correspond to mudstone, wackestone and packstone according to Dunham 1962, with the presence of two species of foraminifera, Hedbergella Trocoidea Longoria and Heterohelix Moremani Cushman, that allow to establish a relative age of the Aptian to the Albiano; limestones are generally made up of SiO2 in 5.30%wt; P2O5 at 2.97%wt and CaO at 70.88%wt.; MgO at 0.98%wt, Al2O3 at 1.15%wt, SO3 at 1.98%wt, K2O with 0.35%wt, Cl with 0.19%wt, Fe with 0.29%wt, Sr with 0.24%wt.; Te with 0.01ppm, Cs with 0.016ppm, Ba with 0.03ppm, V with 0.018ppm and Ti with 0.038ppm%); and its primary utility is for the manufacture of cement and lime. [ABSTRACT FROM AUTHOR]

Limestone rock has long been of great importance economics for society, due to its physicochemical characteristics that allow its use as input for the manufacture of covering, lime, cement, concrete and stuc. At the municipality of Manaure-Cesar, La Tomita sector outcrop limestones interspersed with shales, corresponding to the Lagunita Formation of the Cogollo Group. This research has as its main objective to know the geographical distribution of the Lagunita Formation, the chemical composition of limestones and their potential use as an industrial material. This is done using cartographic, stratigraphic and geochemical (X-ray fluorescence) techniques compared to the guidelines of Colombian Technical Standard (NTC) 5163. This concluded that in the village La Tomita the limestones texturally correspond to mudstone, wackestone and packstone according to Dunham 1962, with the presence of two species of foraminifera, Hedbergella Trocoidea Longoria and Heterohelix Moremani Cushman, that allow to establish a relative age of the Aptian to the Albiano; limestones are generally made up of SiO2 in 5.30%wt; P2O5 at 2.97%wt and CaO at 70.88%wt.; MgO at 0.98%wt, Al2O3 at 1.15%wt, SO3 at 1.98%wt, K2O with 0.35%wt, Cl with 0.19%wt, Fe with 0.29%wt, Sr with 0.24%wt.; Te with 0.01ppm, Cs with 0.016ppm, Ba with 0.03ppm, V with 0.018ppm and Ti with 0.038ppm%); and its primary utility is for the manufacture of cement and lime. [ABSTRACT FROM AUTHOR]

The Limestone rock has been used since ancient times for different purposes due to its economic importance and physicochemical characteristics that allow its use as an input in the construction's industry, agrochemicals, smelting, glass and chemicals. In the Coohornical Mining Center Quarry, municipality of Distracción-La Guajira, limestones intercalated with shales outcrop, corresponding to the Lagunitas Formation of the Cogollo Group. The objectives of this research are to determine the geographic distribution of CaCO3 and MgCO3 concentrations in the Lagunitas Formation, to establish chemical characteristics and to classify petrographically by means of cartographic, stratigraphic, petrographic and geochemical techniques (X-ray fluorescence and X-ray diffraction). This led to conclude that, in the Coohornical Mining Center Quarry, limestones texturally correspond to mudstone and packstone, with presence of fossils such as bivalves, ostracods and gastropods, medium and fine sand size clastic grains, among the non-skeletal allochemicals there are peloids surrounded by a micrite matrix joined by discontinuous cement and intraparticular porosity; The geochemical results allowed identifying that the limestones are constituted by CaCO3 with a range 88.98%wt - 99. 13%wt, CaO with a range of 46.81%wt - 53.12%wt, P.P.C. 39.08%wt - 43.71%wt, SiO2 in a range of 0.41%wt - 0.83%wt, being the areas with the highest concentration of calcium carbonate (CaCO3) located in the northern part of the quarry and magnesium carbonate (MgCO3) in the extreme southeast and center; compared with the guidelines of the Colombian Technical Standard (NTC) 5163, it was stipulated that its primary use is for the manufacture of cement and lime. [ABSTRACT FROM AUTHOR]

Crude oil is a highly complex natural mixture consisting predominantly of hydrocarbons [alkanes (paraffins), alkenes (olefins), and aromatic compounds] and other elements such as sulfur, nitrogen, and oxygen. In Cuba, work is being done on the exploitation of new oilfields deposits in the Northern Cuban Oil Belt. The goal of this paper is to characterize the crude oils from the point of Reservoir Geochemistry, using the high-resolution gas chromatography technique and the study of the physicochemical properties, in samples from six oil wells from the western sector of the Varadero oilfield. The fingerprints of the crude oil were obtained, the star diagrams were constructed to establish the possibilities of communication between the wells, from the ratios between compounds. The main results obtained show the existence of better communication between wells VW1003 and VW1007 with a difference of 1.91%, with the rest of the wells studied behaving differently. In addition, the physicochemical properties of the oils were studied, the results of which show that they are extra-heavy oils, with high content of sulfur and asphaltenes and. These properties show the similarity in their commercial quality with the crude oil discovered in the other blocks of the Varadero field, characterized by heavy, extra-heavy, highly sulfurous crude oils, belonging to Family I of Cuban crude oils. [ABSTRACT FROM AUTHOR]

The objective of this paper is to describe the main characteristics of the occupational sequence of the Pashimbi archaeological site, one of the most complete documented sites in the Ecuadorian Upper Amazon. Radiocarbon dates, geochemical analyses, and cultural material correlation by strata allowed for a comprehensive reading of the data, determining seven times of human activity in four millennia: Colonial (183 BP), Tena (602-309 BP), Cosanga II (860 BP), Moravia (1380-1222 BP), Cosanga I (1464-1380 BP), Pambay (3110-1888 BP), and Pashimbi (4025-3450 BP). Finally, a first approximation to the subsistence forms of the groups that inhabited this territory was made. [ABSTRACT FROM AUTHOR]