Repositorio Digital Sernageomin
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Visita técnica a puntos críticos de la comuna de Cauquenes por posibilidad de remociones en masa, Región del Maule
No full textRevisor: Carolina Jara I. -- Informe Técnico -- Unidad Ejecutora: Unidad de Asistencias Técnicas y Emergencias Geológicas, Santiago11 p
Integrated U-Pb and Hf zircon and whole-rock Nd isotopes studies of Devonian granitic rocks from Sierra de San Luis (Sierras Pampeanas, Argentina) : Petrogenetic implications
No full textPrevious geochronological data indicate a protracted Devonian magmatic activity developed in the Sierra de San Luis, Sierras Pampeanas of Argentina, with three major crystallization events: 393±3, 384±2, and 377±2 Ma. Previously reported whole-rock Sm-Nd isotopes data define two average distinctive εNdt values: -1.37 and -3.47, and they are consistent with new data presented here. The first signature is assumed for a parental magma with dominant metasomatized subcontinental lithospheric mantle (SCLM) source, whereas the second signature could represent a parental magma derived of a lower continental crust source hybridized with magmas of the first signature. Notably, the new zircon Hf isotopes performed on the same zircon domains that were previously dated, indicate that the contribution of the source was variable over time. In situ Hf in zircon is relevant to evaluate the compositional evolution of the Devonian granitic magmas in the Sierra de San Luis, since the high variability of the εHft values recorded in zircons indicate that the calculated εNdt values for the samples can only be interpreted as a final picture of the petrogenetic process. Zircon Hf isotopes data suggest that the zircon crystallized from a magma with variable composition, recording two major events, yielding two εHft signatures: (1) -3.54 and (2) -6.85. A third composition, yield a less representative εHft value of -5.44, and represent a εHft signature (3).pp.167-18
Remoción en masa en algunas laderas costeras de la cuidad de Castro, comuna de Castro, región de Los Lagos
No full textInforme Técnico -- Unidad Ejecutora: Oficina Técnica de Puerto Varas17 p
Geología del cuadrángulo Río Claro, región del Maule, Chile
No full textInforme Registrado IR-23-11065 p
Seminario: Zonificación de áreas expuestas a remociones en masa en la región de Los Ríos, escala 1:250.000. Presentación de material de difusión (dípticos y videos)
No full textCorresponde a anexo de BSNGM 16319 DVD: Zonificación de áreas expuestas a peligros de remoción en masa en la región de Los Ríos ; Xterrae Geología11 p
Remociones en masa : ¿Qué características tienen y dónde ocurren en la región de Antofagasta?
No full textCorresponde a anexo de BSNGM 16371 DVD: Zonificación de áreas expuestas a peligros de remoción en masa en la región de Antofagasta ; Xterrae Geologí
Visita Técnica por condición de estabilidad de laderas en quebrada Rodelillo, comuna de Viña del Mar, región de Valparaíso
No full textRevisor: Javier Fernández -- Informe Técnico20 p
Origin of the vanadium-uranium geochemical anomalies in the limestones of the Puyango Formation, La Sota (Ecuador) : Preliminary results
No full textVanadium (V) and uranium (U) are critical elements for the energy and technology industry. They are characterized by low abundance in the earth crust´s rocks, but can be concentrated and give rise to sedimentary mineral deposits as a result of redox processes during sedimentation and diagenesis. The anomalies of V-U in La Sota, Ecuador, are found in black limestones and black calcareous shales of Cretaceous age. Here we present the results of a geochemical study and a multivariate geostatistical analysis, which enables us to infer four different associations: 1) disseminated organic matter in the limestones that hold V and Zn, probably in the form of organometallic complexes; 2) phosphatic minerals and concentrations of U, HREE and Ni, which may be incorporated as trace elements in the phosphates, compatible with sedimentation in an anoxic environment; 3) Ca in carbonates from a marine environment; and, 4) litophile elements associated with detritic minerals, such as quartz, plagioclase, feldspar, micas, clays and oxyhydroxides of Fe-Mn-Ti, produced by weathering and erosion. Our findings suggest that V is associated mainly with the organic matter of marine origin in the bituminous limestones, while U is associated with P, thereby indicating the formation of uraniferous phosphates during sedimentation.pp.75-9
Reinspección de remoción en masa en gruta de Lourdes, localidad de Mehuín, comuna de Mariquina, región de Los Ríos
No full textInforme Técnico -- Unidad Ejecutora: Dirección Regional de Los Ríos, Valdivia22 p