Preliminary Characterization of MTBE in Deep Wells of the Aquifer Patiño, Metropolitan Region of Asuncion, Paraguay

The objetive and goals are: Understand the evolution and trends of the MTBE and bi-products in the Aquifer under the effect of dry and wet seasons.; Identify key factors that influence the recovery of the water quality of this aquifer; Provide with accurate information to the community on the water quality (other parameters were analyzed) of their supplier.; and Recommend measures & policies to improve water management in Metro Area.CONACYT - Consejo Nacional de Ciencias y TecnologíaPROCIENCI

Utilización de los SIG en la Planificación de una Estancia Ganadera.

"Se presenta los aporte de la utilización de las herramientas SIG en el ámbito ganadero un gran aporte para la planificación"CONACYT - Consejo Nacional de Ciencias y TecnologíaPROCIENCI

Determinación del Metil Ter Butil Eter (MTBE) como agente contaminante en el Acuífero Patiño. Departamento Central-Paraguay

El objetivo general de este proyecto es determinar la presencia de MTBE (Metil Terbutil Eter) y sus productos de degradación en el acuífero Patiño de la zona de Asunción y el Área Metropolitana de sugerir la biorremediacion y las medidas normativas a implementar.CONACYT - Consejo Nacional de Ciencias y TecnologíaPROCIENCI

Estudio de caso: Validación de método SPME-GC/MS para la determinación del Metil Tert-butil éter y sus productos de degradación en agua subterránea

El Metil tert-butil Eter (MTBE) es un combustible oxigenado ampliamente utilizado en Paraguay, asi como en muchos países de América del Sur como elevadores del octanaje para reemplazar los aditivos tóxicos prohibidos en la gasolina. En varios países europeos se encontró en aguas subterráneas debido a la fuga de tanques de gasolina. Se realizó la validación del método analitico para MTBE y sus sub-productos de degradación como Tert-butil Alcohol (TBA) y Ten butil Formiato (TBF) mediante micro extracción en fase sólida y cromatografia de gases acoplada con espectrometria de masas (SPME-GC/MS), utilizando procedimientos estandarizados de validación.CONACYT - Consejo Nacional de Ciencias y TecnologíaPROCIENCI

F-rich strongly peraluminous A-type magmatism in the pre-Andean foreland Sierras Pampeanas, Argentina:Geochemical, geochronological, isotopic constraints and petrogenesis

The petrogenetic nature of A-type granites is a controversial problem. The Vinquis batholith in the Sierras Pampeanas of Argentina contains unusual F-rich and strongly peraluminous A-type monzogranites. A new LA-MC-ICP-MS U–Pb zircon crystallization age of 355±7Ma indicates emplacement in latest Devonian or earliest Carboniferous time, overlapping with extensive metaluminous A-type magmatism in the area. The monzogranites have a restricted range of SiO2 content (71.5–74.8 %), they are poor in Ca (0.54–1.4% CaO) and rich in FeOt, with relatively high FeOt/(FeOt+MgO) values ranging from 0.77 to 0.86 (average = 0.80) Both [FeOt/ (FeOt+MgO)] vs. SiO2 and [(Na2O+K2O)−CaO] vs. SiO2 plots indicate ferroan and alkali-calcic signatures typical of A-type granitoids. The samples have MgO/TiO2>1.2 and are moderately enriched in total alkalis (average 8.18%), with high K2O/Na2O values of 1.40–2.24. The granites are strongly peraluminous, with ASI (molar 12O3/[CaO+Na2O+K2O]) values of 1.2 to 1.3. The high P2O5 content (0.23–0.37%) is distinctive and close to values reported for other Paleozoic F-rich peraluminous A-type granites in the Sierras Pampeanas. They have moderate contents of high field strength elements (e.g., Zr, Nb, Th, Y, etc.) and moderately fractionated to flat REE patterns [(La/Yb)N in the range 4.8–19.6] showing significant negative Eu anomalies (Eu/Eu*=0.41). Biotite has a distinctive composition, with relatively high Fe2+/(Fe2++Mg) ratios (0.61–0.74) and high F (0.55–1.42wt.%) content. Together with the whole-rock chemistry this may be useful in identifying strongly peraluminous A-type granites. In addition, the Rb/Sr vs. Th+Zr+Ce diagram may be an appropriate discriminant between metaluminous and peralkaline A-type granites, strongly peraluminous A-type granites and strongly peraluminous orogenic granites. The geochemical evidence indicates that differentiation of the granitic rocks occurred by mineral fractionation from a F-rich peraluminous parental magma, dominant of plagioclase, K-feldspar, biotite, and accessory minerals such as zircon, monazite, xenotime, and oxides. The peraluminous composition and isotope data (εHf,355 and εNd,355 ranging from −9.5 to −1.5 and −6.1 to −7.8, respectively), together with abundant inherited Ordovician and Cambrian zircon, strongly suggest a dominantly metasedimentary source. The whole-rock and biotite compositions indicate that the Vinquis batholith crystallized under mainly oxidizing conditions, whereas Early Carboniferous metaluminous to weakly peraluminous A-type granites of the Sierras Pampeanas crystallized under dominantly reduced conditions