Geophysical methods in protected environments. Electrical resistivity tomography

Abstract

There is a strong interest in protecting the environment with the aim of its long-term preservation. Sometimes the heritage value of these natural areas is related to their biodiversity as there are restricted ecosystems that depend directly on them. In other cases, a singular geological record might exist, essential for the understanding of certain processes affecting the planet, such as volcanic events or glacial periods. To achieve the protection and conservation of these areas it is necessary to generate knowledge about the distribution of geological materials and groundwater masses, to study the parameters that dominate the behavior of these systems, and then define those elements that require special protection or attention. In these protected environments, research methods with minimal environmental impact should be used. Therefore, indirect methods, such as geophysical techniques, are reliable and complementary tools with a minimum environmental impact and are therefore useful for researching these unique areas. The IGME has conducted several geophysical surveys in different protected environments in Spain with the aim of achieving a better understanding, and thus facilitate their preservation and exploitation in a sustainable manner. In this paper, we present a review of some case studies where geophysical methods have been used. In all the cases, electrical resistivity tomography has been the axis of the geophysical research and stands out due to its great effectiveness. The main objective of this communication is to divulge and increase awareness of the important role that these geophysical methods can play in the sustainable study of these unique places.

Uso del método potencial natural en la exploración de agua subterránea: caso de estudio Hospital de Olanchito

“…Tradicionalmente los métodos resistivos se han utilizado ampliamente en estudios hidrogeológicos (Fonseca-Benítez, 2018;López-Loera, 2014;Salguero, 2002;Sánchez-Aguililla, Ramiro-Camacho, y Torre, 2017), sin embargo estos presentan algunas desventajas sobre todo cuando la profundidad de exploración es mayor a los cientos de metros, donde el trabajo de campo se vuelve poco práctico ya que se requieren extender cables hasta por 1 Km de longitud, y además el equipo requerido es costoso, pudiendo sobrepasar los 50,000 USD. Recientemente, gracias a los avances en la electrónica, han aparecido en el mercado equipos con métodos alternativos, como ser el de la casa China PQWT de potencial natural que se muestra como equipo de bajo costo y fácil uso, que basado en métodos magnetotelúricos MT y audio magnetotelúricos AMT permiten obtener información del subsuelo a grandes profundidades sin necesidad de extender grandes longitudes de cable en superficie.…”

Hydrogeochemical, isotopic and geophysical characterization of saline lake systems in semiarid regions: The Salada de Chiprana Lake, Northeastern Spain

“…The Electrical Resistivity Tomography (ERT) method provides a 2D model of the ground by defining the geometry of an aquifer in areas of moderate geological complexity. It is a widely applied geophysical exploration method to investigate wetlands and endorheic hydrological systems (Plata, 1999;Rubin and Hubbard, 2006;Andrews et al, 1995;Owen et al, 2006;Rein et al, 2004;Descloitres et al, 2008;Ruiz et al, 2006;Rubio Sánchez-Aguililla et al, 2017).…”