Job description
Passive seismic data (ambient noise, microseismicity, teleseismic events) are noisy and irregular, and off-the-shelf tools rarely fit. We are looking for a seismologist who understands full waveform inversion (FWI) from the inside – physics, mathematics, algorithms and code – to build an in-house FWI capability based on code we understand, control and can modify.
The role combines R&D and production.
R&D – Full waveform inversion
- Design, develop and adapt an FWI workflow for passive seismic data, covering the full chain from raw data to velocity model
- Build and optimize forward-modeling and adjoint-based inversion components: gradient, misfit functions, regularization, uncertainty
- Benchmark on synthetic models, then apply to Mantle8 field datasets
- Assess and extend open-source codes (SPECFEM, Salvus, Devito, SeisFlows, ObsPy…), with attention to licensing
- Run and optimize inversions on HPC / cloud infrastructure
Production – Seismic imaging for exploration
- Process dense nodal-array datasets (Stryde, SmartSolo): pre-processing, Green's-function retrieval, source characterization
- Apply established methods – ambient-noise tomography, traveltime tomography – to deliver models within project timelines
- Share clear results with geologists and geochemists and integrate them with other geophysical data
- Contribute to acquisition design (array geometry, sensor selection)
- Document methods and code, and write technical reports
First milestones
- Months 1–3: take ownership of data and tools, choose the code base, first synthetic tests
- By month 6: first FWI results on Mantle8 field data
Profile required
Required
- PhD in seismology, geophysics, applied mathematics or a related field, with a thesis focused on full waveform inversion
- Early career: recent PhD graduate, up to 5 years of experience after PhD
- Hands-on development of FWI code: you have written, tested and benchmarked significant parts of an inversion workflow – not only used commercial software as a black box
- Complete view of the FWI protocol, from data to model, and in-depth understanding of each component
- Solid background in seismology and wave propagation
- Strong scientific programming (Python and/or C/C++, Fortran, Julia), numerical methods and Git
- Experience with HPC / parallel computing
Desirable
- Passive seismology: ambient-noise interferometry, teleseismic or microseismic data
- Ambient-noise or traveltime tomography in an applied setting
- Machine learning for seismic data
- Joint inversion or exploration geophysics
Personal qualities
- Adaptability when working with complex, noisy data
- Autonomy, rigour and the ability to deliver on deadlines
- Clear communication within a multidisciplinary team
- Working proficiency in English; French is a plus
Non-linear career paths are welcome: what matters most to us is your expertise.
What we offer
- A central role in building a new capability in natural hydrogen exploration
- Access to proprietary datasets, with freedom to publish and present at conferences
- An interdisciplinary geoscience team and modern computing resources
- Health insurance fully covered for the employee, meal vouchers, CESU
Recruitment process
- HR interview
- Technical interview with the Geophysics Lead
- Final interview with the CTO
Please include a short description of the FWI code you have developed (scope, language, open-source or not). A link to a repository is welcome.
Company description
🇬🇧 Mantle8 is a deep-tech exploration company dedicated to unlocking the potential of natural hydrogen as a new clean energy resource.
By combining advanced geoscience, subsurface modeling and cutting-edge simulation technologies, Mantle8 develops innovative exploration methods to identify and evaluate natural hydrogen systems deep within the Earth.
Our multidisciplinary team brings together geoscientists, engineers, data scientists and explorers who share a common ambition: advancing scientific understanding while building the foundations of a new energy frontier.
From regional exploration concepts to prospect generation and technological development, Mantle8 works at the intersection of research, innovation and industrial application to accelerate the emergence of natural hydrogen as part of the global energy transition.
At Mantle8, exploration is not only about discovering new resources — it is about expanding knowledge, challenging assumptions and building solutions for the future of energy.
Why is everything in English if Mantle8 is based in the heart of the French Alps?
Because Mantle8 is an international adventure.
As of March 2026, our team includes 21 people representing 9 different nationalities. This diversity is one of our greatest strengths, and English is the language that allows everyone to collaborate, debate ideas and build things together.
We love our home in the French Alps, but inside Mantle8 our common ground is English — from meetings and technical discussions to emails and, yes, even our jokes.
So if you’re thinking about joining us, English is not just helpful — it’s essential to be part of the conversation.
🇫🇷 À propos de Mantle8
Mantle8 est une entreprise deep-tech d’exploration dédiée à révéler le potentiel de l’hydrogène naturel comme nouvelle ressource d’énergie propre.
En combinant géosciences avancées, modélisation du sous-sol et technologies de simulation de pointe, Mantle8 développe des méthodes d’exploration innovantes permettant d’identifier et d’évaluer les systèmes d’hydrogène naturel présents en profondeur dans la Terre.
Notre équipe pluridisciplinaire réunit géoscientifiques, ingénieurs, data scientists et explorateurs partageant une ambition commune : faire progresser la connaissance scientifique tout en construisant les bases d’une nouvelle frontière énergétique.
De la génération de concepts d’exploration régionaux à l’identification de prospects et au développement technologique, Mantle8 opère à l’interface entre recherche, innovation et application industrielle afin d’accélérer l’émergence de l’hydrogène naturel dans la transition énergétique mondiale.
Chez Mantle8, l’exploration ne consiste pas seulement à découvrir de nouvelles ressources — il s’agit aussi d’élargir la connaissance, de remettre en question les certitudes et de construire des solutions pour l’énergie de demain.
Pourquoi tout est-il en anglais alors que Mantle8 est basée au cœur des Alpes françaises ?
Parce que Mantle8 est avant tout une aventure internationale.
Début mars 2026, notre équipe compte 21 personnes représentant 9 nationalités différentes. Cette diversité est l’une de nos plus grandes forces, et l’anglais est la langue qui nous permet de collaborer, de débattre d’idées et de construire ensemble.
Nous sommes très attachés à notre ancrage dans les Alpes françaises, mais chez Mantle8 notre langue commune est l’anglais — que ce soit pour les réunions, les discussions techniques, les e-mails et, oui, même nos blagues.
Donc si vous envisagez de nous rejoindre, l’anglais n’est pas seulement utile : il est essentiel pour faire partie de l’aventure.
On 10/12/2026