A new limit for the NW Río de la Plata Craton Border at about 24ºS (Argentina) detected by Magnetotellurics

Old South American structures constitute a puzzle where the Río de la Plata Craton is the most important clue in the assembly of SW Gondwana. The present study is aimed at characterizing the western border of the Río de la Plata Craton on the basis of magnetotelluric studies. Magnetotelluric (MT) data were acquired along an approximately NW-SE 750km profile at about 24ºS, from the Sub-Andean Ranges in the province of Salta (NW) to the Formosa Province frontier (SE) next to Paraguay River. Distortion and structure dimensionality analysis indicates that MT responses are two-dimensional with a NS strike orientation, consistent with the regional geological strike. A 2-D inversion of the data provided a model showing a lateral discontinuity, possibly associated with cratonic structures. The high resistivity observed (>5000ohm·m), from about the middle of the profile toward its eastern end, may be interpreted as the terranes accreted to the Río de la Plata Craton during Neoproterozoic to Cambrian times, or as the Río de la Plata Craton itself. Along the profile from the surface to a depth of about 10km the resistivity model shows a significant resistivity variation in the structure. The resistive block identified at the western end of the profile represents the Sub-Andean system. The markedly enhanced low-resistivity structure (~1 to 10ohm·m) corresponds to a sedimentary pile whose thickness decreases from NW to SE

Towards a Hand Exoskeleton for a Smart EVA Glove

In this paper we investigate the key factors associated with the realization of a hand exoskeleton that could be embedded in an astronaut glove for EVA (Extra Vehicular Activities). Such a project poses several and varied problems, mainly due to the complex structure of the human hand and to the extreme environment in which the glove operates. This work provides an overview of existing exoskeletons and their related technologies and lays the ground for the forthcoming prototype realization, by presenting a preliminary analysis of possible solutions in terms of mechanical structure, actuators and sensors

Preliminary data on the structure and potential of the Tocomar geothermal field (Puna plateau, Argentina).

AbstractThis study presents new stratigraphic, structural and hydrogeological data on the Tocomar geothermal volcanic area (Puna plateau, Central Andes, NW Argentina), together with preliminary geochemical and magnetotelluric data.The main geothermal reservoir is located within the fractured Pre-Palaeozoic–Ordovician units. The reservoir is recharged by meteoric waters. Geothermal fluids upwell where main regional structures intersect secondary structures associated with the development of the Tocomar basin. Preliminary data indicate a reservoir temperature of ∼ 200° C and a local geothermal gradient of ∼ 130° C/km associated with the Quaternary volcanic activity in the Tocomar area

3-D magnetotelluric inversion for geothermal exploration in Socompa volcanic zone, NW Argentina

The Socompa volcano lies in the arid core of the Puna region. It is a stratovolcano whose summit reaches 6,051 m high and it is located between the limit of the Antofagasta region, Chile and the Province of Salta, Argentina. The volcano is located in a sterile environment, and the diversity and abundance of life that has been documented in the region is explained through a geothermal system revealed in the form of fumaroles and hot springs of stable temperatures. These manifestations suggest the importance of a magnetotelluric (MT) research to study a potential geothermal field that has not been explored. The MT method has been widely used in geothermal exploration. In December 2017, we carried out the first survey in the region. The present work is oriented to determine the top of the layer that could be the reservoir of the geothermal system. According to the literature, thermal manifestations are located in the Socompa Lagoon and in Quebrada del Agua fault. The survey consisted in 34 MT stations that covered the area. A 3D inversion was performed employing the ModEM code using a frequency range from 1 to 1000 Hz. The results showed a highly conductive layer at approximately 450 m depth.Facultad de Ciencias Astronómicas y GeofísicasUniversidad de Buenos AiresConsejo Nacional de Investigaciones Científicas y Técnica

Audiomagnetotelluric survey at the Bañitos-Gollete geothermal area, main Andes Cordillera of San Juan, Argentina.

The present research explores the Bañitos-Gollete geothermal field located in the Frontal Andes Cordillera over the Pampean flat-slab. We carried out an audiomagnetotelluric survey in order to define the underground geoelectrical structure and to understand the link between the geothermal fluid flow path and the main geological structures. 2-D audiomagnetotelluric models suggest that the deep-rooted N-S fault system controls the geothermal flow path. We propose a conductive heat-driven system, taking into consideration the geologic setting and the supposed low geothermal gradient of this tectonic environment. The mature Na-Cl waters from Gollete and an estimated reservoir temperature of ~140ºC are consistent with this conceptual model. Further investigations are required to assess the geothermal potential of the study area, and the present work likely represents only the first but necessary step in the exploration process