4-4-4-4-4-4-4-4-4-4-4-4-4 From: Jean-Philippe Métaxian <jp.metaxian@xxxxxxxxx> *Post-doc position in seismology **applied to geothermal prospecting* â?¦ ISTERRE attachment, IPGP geographical assignment in Paris â?¦ Position open on fixed-term contract for *24 months* â?¦ Category A â?? Researcher *The structure you will join* The Institute of Earth Sciences (ISTerre) is a joint research unit (UGA / CNRS / USMB / IRD / Univ Gustave Eiffel) of nearly 300 people. This unit is part of the Observatoire des Sciences de l'Univers de Grenoble (OSUG) and of the PAGE research cluster of the Université Grenoble Alpes (UGA). ISTerre focuses on the physical and chemical study of the planet Earth. By combining observations of natural objects, experiments and modelling of complex phenomena, the institute studies the major systems related to the internal Earth. In Ile de France, the UMR 7154 Institut de Physique du Globe de Paris (IPGP) hosts one of the IRD researchers member of the UMR ISTerre. The IPGP's mission is the creation and transmission of knowledge in the fields of geosciences to which is added a mission of observation of natural phenomena. The institute conducts research in all fields of study of the solid Earth (geophysics, geochemistry, quantitative geology) by combining observation on land and at sea and analysis and measurement in the laboratory to the construction of conceptual, analog and digital models. The person recruited will be supervised by an IRD/IPGP team in the laboratory and 2 people within the company Storengy. He will have to carry out his mission alternatively in one and the other structure, 60% at Storengy company located in Bois Colombes, 40% at the IPGP located in Paris. Possibility of field campaigns including the deployment of seismic sensor networks. *Context* The project comes to deepen scientifically a partnership started between IRD (https://urldefense.com/v3/__https://www.ird.fr__;!!IKRxdwAv5BmarQ!M7jiDkhPdZ_8CHXCAL4OCiUqjdsvRshmnJSMIvsm008dtnaTC8RZ-mj7Z7gVqZw$ ) and STORENGY in 2016 on the field of passive seismic recording applied to geothermal prospecting. This partnership started with a seismic measurement campaign in Indonesia on the Muara Laboh geothermal site (Sumatra) and continued in 2018 with the signature of a scientific agreement for the realization of a series of recurrent measurement campaigns over a period of 5 years. This new research collaboration, entitled "Reservoir characterization from low-frequency seismic signals for exploration and monitoring purposes", has two objectives: 1. Conduct low-frequency passive seismic signal acquisitions (i.e. ambient seismic noise) at several sites with a broadband seismic sensor array that was acquired by STORENGY as part of the collaboration. 2. To provide expertise in the interpretation of these new data, including methodological developments to analyse the acquired data. The project we are submitting focuses on point 2. Our partnership since 2016 has shown that an effort must be made to develop tools to analyse the data acquired in the field. *Mission*: Under the responsibility of the scientific coordinators Jean-Philippe Métaxian (IRD) and Alexandre Kazantsev (Storengy): Low frequency passive seismic studies applied to geothermal prospecting and monitoring of geothermal activity. The aim of this project will be to adapt existing seismological tools and methods applied to the study of fault systems or volcanic systems to the context of hydrothermal systems for the location of fluid reservoirs (steam, water) and the monitoring of seismicity generated by hydrothermal activity. Our objectives are to make these tools operational to interpret the data acquired during seismic noise acquisition campaigns and in the longer-term perspective of monitoring geothermal exploitation. This work will be carried out with existing seismic data or data acquired by Storengy during the project. The project aims to locate fluid reservoirs (steam, water), to detect and locate seismogenic zones and to integrate this information into a model of the hydrothermal system using different seismological techniques. The objectives are more specifically: Task 1. 3D tomographic imaging of structures using ambient seismic noise. The imaging allows to identify the main trends of the local geological structure, to detect possible low velocity layers in the near subsurface, to locate strongly faulted zones or fluid reservoirs in case of sufficient velocity anomaly. The knowledge of the 3D velocity model is also useful for the accuracy of the seismicity localization. Task 2. Imaging from spectral amplification, H/V map and polarization analysis in the 0.5-10 Hz frequency band. This information is used to better constrain the imaging performed in Task 1 via the extraction of local 1D models at each station. Task 3. Detection and localization of emerging seismic sources such as tremors or long period signals (LP) characteristic of fluid circulation processes using seismic antenna and back-projection techniques. *The profile we are looking for* You have a PhD in geophysics, obtained in 2019-2020 or 2020-2021, with skills in seismology, python programming, and OS Unix proficiency. You have skills in seismic data analysis, methods of analysis of dense sensor networks, fieldwork, and teamwork. 4-4-4-4-4-4-4-4-4-4-4-4-4 ------------------------------
