DTU Studieprojekt - Towards accurate subsurface thermometry using luminescence techniques

Towards accurate subsurface thermometry using luminescence techniques

Udbyder
Vejleder
Sted
København og omegn
Temperature is a primary factor in countless physical, chemical and biological processes and reactions; as a result, about 80% of the global sensor market comprises of devices that monitor present-day temperatures. Nevertheless, many key questions in both basic science as well as industrial applications require the ability to reconstruct temperatures in the deep past – way beyond the historical and/or instrumental records. Recently, DTU Nutech has pioneered a novel methodology, which enables to measure and translate a well-defined physical parameter of natural crystals (luminescence) into corresponding palaeo-temperatures on an unprecedented, thousand-year-long timescale:

https://ing.dk/artikel/dansk-metode-kan-lynhurtigt-afsloere-undergrundens-sande-temperatur-177598

Having a solid footing in radiation physics, this new method sees an increasing demand in several derivative disciplines such as geoscience (e.g. for understanding the evolution of mountains) and geoengineering (e.g. for geothermal/hydrocarbon prospecting).

Tasks
In the current project, we seek to extend the method’s current applicability range (0 - 70 °C) by about fourfold (0 - 300 °C), with the aim of demonstrating a simple technology transfer to geothermics (research of medium-high enthalpy geothermal resources). The research project will focus on the characterisation of various luminescence signals in a suite of borehole samples from the Central European Craton (KTB superdeep borehole), where the underground temperature has been stable for millions of years. After an initial physico-chemical separation of the target minerals from the drill cores, you will measure the minerals’ natural luminescence, and then conduct a series of experiments to study luminescence response to ionising radiation and heat. Eventually, the resultant data will be evaluated using a predictive physical model – whose calibration and improvement will enable its use in environments of unknown thermal conditions. You will be able to play with the deepest rock sample ever obtained (originating ~9 km underground), among others!

During the project, you will enjoy a hands-on experience with a broad array of cutting-edge radiation physics instruments, including low-level gamma spectrometers, various generations of Risø TL/OSL readers, (micro) X-ray fluorescence spectrometers, and optionally the CryOgenic LUminescence Research (COLUR) facility. In addition, you may get involved in the development of new instruments, e.g. the spatially-resolved infrared photoluminescence (SR-IRPL) reader. The project is of strong multidisciplinary nature, and is thus sufficiently flexible to follow your own personal interest(s) and areas of competence. Primarily, we seek to clarify and improve our understanding of the basic physical processes occurring inside natural crystals exposed to radiation and heat with a motivation to develop concrete geological and geotechnical applications. DTU Nutech has >30 years of research in developing new instruments to facilitate cutting edge research in ionizing radiation dosimetry.

Learning objectives

• Recognising the environmental processes that affect the build-up and removal of luminescence in subsurface rocks.
• Describing present-day environmental conditions at the KTB borehole (Germany).
• Characterising the luminescence within representative samples from the KTB borehole (Germany) using selected veteran/novel radiation measurement techniques.
• Analysing the quality and reproducibility of results, in light of the various environmental and radiation factors.
• Evaluating the individual characteristics of luminescence signals, and their overall trend with depth using the evolving feldspar luminescence model.
• Participating in the development of novel equipment (spatially-resolved IRPL reader), and in the formulation/testing of the feldspar luminescence model.

Supervision
Supervisor: Mayank Jain

Co-Supervisor: Benny Guralnik

Forudsætninger
Curious mind; Enjoys handiwork/engineering; Experimentalist mentality (try – fail – try again); Comfortable with math and modelling (MATLAB)

Emneord

• Fysik
• Materialer
• Lasere
• Mikro- og nanoteknologi
• Optik
• Sensorer
• Nanopartikler

• dosimetry
• Geology
• geothermal
• Luminescence
• palaeothermometry
• temperature
• thermometry

Navn
Mayank Jain

Stilling
Seniorforsker

Mail
maja@dtu.dk

Vejleder-info
Kandidatuddannelsen i Fysik og Nanoteknologi
Vejleder
Mayank Jain

ECTS-point
30

Type
Kandidatspeciale