Website INRS - Institut national de la recherche scientifique
Soft clastic sedimentary facies transformation and deformation using microtomography
The detailed analysis of sedimentary facies enables researchers to decipher the formation processes and thus to reconstruct the environmental conditions in which they have been deposited. However, little is known about the transformation of these facies between the deposition of the waterlogged sediments and their consolidation, as well as about the disturbances that these facies undergo during sampling.
The objective of the project is to understand how dewatering and compaction affect the internal structure of clastic sediments through observation of potential changes in grain orientation and arrangement, and porosity within the facies. It also aims at evaluating what disturbances affect these unconsolidated sediments during coring in the field or sampling in the laboratory. The project will focus on several types of varved (annually laminated) sediments which are usually used to study past hydroclimatic conditions. It will combine classic analyses of thin sections with petrographic and scanning electron microscopes, and advanced techniques developed at INRS including computed tomography and micro-CT.
Grain size of varved sediments using microtomography
Particle size of sediments accumulated in lakes is an indicator of the competence of the tributaries. In varved (annually laminated) lake sediments, the grain-size variation combined with varve thickness allow the reconstruction of hydroclimatic records over several hundred years, far beyond the instrumental record. The research team has developed and used an image analysis technique of thin sections of these varved sequences to obtain long grain size series of annual resolution for paleoclimatic reconstruction. However, this technique requires to prepare thin sections and use a scanning electron microscope which make the process relatively tedious.
The objective of this project is to develop a new micro-CT image analysis protocol to obtain data sets similar to those obtained using the method described above. The laboratory has just acquired a micro-CT to analyze whole sediment cores, allowing to bypass the preparation of thin sections and to select areas more representative of an entire year of deposition. The project will test the reliability, reproducibility and robustness of the method with existing series, and if proven successful, will be used to produce a new paleoclimatic series.
START DATE: As soon as the sanitary and administrative conditions allow.
A scholarship of $21,750 per year is available for 3 years. A tuition exemption program is available for international students. Holding or being eligible to an NSERC or FRQNT scholarship is an asset.
University degree in Earth science, oceanography, physics, or physical or geological engineering. Excellent computer proficiency. Experience in image analysis and an interest in environmental issues are assets, but are not essential. Willingness to learn French. French language classes are offered at INRS to facilitate the student integration in the everyday life.
HOW TO APPLY
Interested candidates are invited to send an application package in one PDF file to email@example.com including the following documents:
- a curriculum vitae
- a cover letter
- all university transcripts
- a list of practical and technical skills
- names and address of two referees
Review of applications will begin on June 10, 2020, and continue until the position is filled.
To apply for this job email your details to firstname.lastname@example.org