Portrait

Understanding Tight Sedimentary Rocks for Safer Oil and Gas Operations

How can we improve our understanding of the rock formations that play a decisive role in wellbore stability and safe offshore hydrocarbon production? Postdoctoral researcher Ermis Proestakis investigates the electrical and rock-physical properties of tight sedimentary rocks - knowledge that builds the foundation for future decision-making on unconventional reservoirs, supporting safer offshore operations and contributing to Europe’s energy security.

Ermis Proestakis, Postdoctoral Researcher at DTU Offshore

Tuesday 04 November 2025

Mathias Andreas Ørby

Ermis Proestakis is a postdoctoral researcher at DTU Offshore, specialising in petrophysics. Originally from Greece, he obtained a diploma in Mineral Resource Engineering at the Technical University of Crete before moving to Denmark to pursue an MSc in Petroleum Engineering at DTU. His enthusiasm for research led him to complete a PhD in petrophysics, and he now continues his career as a postdoc, focusing on the characterisation of tight sedimentary rocks.

Research focus

Ermis’ research centres on the electrical and elastic properties of tight sedimentary rocks. These fine-grained formations often act as natural seals (caprocks) but can also be valuable hydrocarbon reservoirs. At the same time, their behaviour is critical for wellbore stability: borehole collapse can lead to major safety and environmental risks.

“We are working with rocks that are complex and not widely studied. By understanding their properties, we provide the industry with the knowledge needed for safer and more informed offshore decision-making,” Ermis explains.

Image of a fossil embedded within the complex, fine-grained matrix of biogenic silica and clay-rich mudstone.
Image of a fossil embedded within the complex, fine-grained matrix of biogenic silica and clay-rich mudstone.

Methods and tools

Conventional laboratory methods often fall short when dealing with very low-permeability rocks. To overcome this, Ermis and his colleagues adapt existing techniques and develop customised procedures.

For example, water saturation is a prerequisite for electrical measurements. Using the standard vacuum method, samples only reached around 60% saturation due to their tight structure. The team therefore designed a two-step approach, combining vacuum saturation with waterflooding - a method that achieved much higher saturation levels and enabled reliable measurements.

Collaborations

Collaboration is a cornerstone of Ermis’ work. He works closely with colleagues at DTU Offshore and with external partners, most notably the Norwegian oil and gas company Aker BP, ensuring that research results can be translated into practical industry applications.

“I really value collaboration, because it allows me to see problems from different perspective and often leads to better solutions,” says Ermis.

Supporting safe offshore operations

The insights from Ermis’ research are directly relevant to oil and gas activities. A better understanding of sealing formations and their rock-physical properties can help predict and prevent wellbore collapse or unwanted fluid migration. This makes offshore operations both safer and more efficient, benefiting industry and society alike.

Facts

Ermis Proestakis

  • Nationality: Greek
  • Educational background:
    • DTU – Technical University of Denmark, 2024
      PhD, Petrophysics
    • DTU - Technical University of Denmark 2019
      MSc, Petroleum Engineering
    • Technical University of Crete 2017
      Diploma of Engineering, Mineral Resources Engineering

  • Position: Postdoctoral Researcher, DTU Offshore

Looking ahead

Together with Aker BP, Ermis is currently exploring the feasibility of developing new tools for improved subsurface characterisation. One aim is to integrate induced polarization and resistivity measurements, which could provide more accurate information from deep wells.

He also sees great potential in automation and artificial intelligence to enhance data acquisition and analysis - though always with a critical perspective on their use.

Contact

Ermis Proestakis

Ermis Proestakis Postdoc