Petrological, petrophysical and petrothermal study of a folded sedimentary succession: the Oliana anticline (Southern Pyrenees), outcrop analogue of a geothermal reservoir

The Oliana anticline (Southern Pyrenees) has been characterized as an outcrop analogue of a geothermal reservoir using field data (stratigraphy and fracturing) and petrological, petrophysical and petrothermal analyses. Five lithofacies were established including conglomerates, hybrid arenites, lithi...

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Detalles Bibliográficos
Autores: Ramirez-Perez, Pedro, Cantarero Abad, Irene, Cofrade Rivas, Gabriel, Muñoz López, José Daniel, Cruset Segura, David, Sizun, Jean-Pierre, Travé i Herrero, Anna
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2023
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/205986
Acceso en línea:https://hdl.handle.net/2445/205986
Access Level:acceso abierto
Palabra clave:Energia geotèrmica
Petrologia
Roques sedimentàries
Pirineus
Geothermal resources
Petrology
Sedimentary rocks
Pyrenees
Descripción
Sumario:The Oliana anticline (Southern Pyrenees) has been characterized as an outcrop analogue of a geothermal reservoir using field data (stratigraphy and fracturing) and petrological, petrophysical and petrothermal analyses. Five lithofacies were established including conglomerates, hybrid arenites, lithic arenites, carbonates and evaporites. Petrophysical measurements indicate widely dispersed values of bulk density, connected porosity, permeability and velocity of compressional acoustic waves. Connected porosity is the factor that mostly influences bulk density, compressional wave velocity and permeability. In turn, diagenetic processes (such as dissolution and cementation) and fracturing, coupled with petrological features such as mineral composition, matrix content and grain size, are the most critical factors controlling rock porosity along the Oliana anticline. Thermal conductivity measures reveal a compositional control on the thermal properties of rocks. Thermal characterization of the structure reveals a low conductive area that matches the carbonate and evaporite succession of the anticline core and a highly conductive zone associated with the detrital succession of the fold limbs. The Oliana anticline has been classified as a petrothermal system due to the low permeability values of the studied sedimentary succession. Despite such classification, this contribution provides a useful exploration tool for future studies of non-conventional geothermal and CO2 storage sites located in folded sedimentary successions in the proximal domain of foreland basins.