In Cegal, from exploring and producing energy resources to capturing and storing greenhouse gases, our work is rooted in a deep understanding of geology and its role in shaping the Earth's energy landscape.
So, what is geology? The short answer is what the word itself means. Geology is the study of the Earth's structure and history. The Encyclopedia Britannica states: “The fields of study concerned with the solid Earth. Included are sciences such as mineralogy, geodesy, and stratigraphy.”
Geology has two main components:
● A descriptive component provides knowledge about minerals and rocks and their properties and distribution.
● A process-oriented component where one seeks to understand how the Earth with its components and structures came to be and how processes continuously change its surface and interior.
In the energy sector, geology is essential, as it provides the foundation for oil and gas extraction and is a prerequisite for renewable energy sources like wind and water.
Kristin Blilie, a geologist at Cegal, says: “Geology encompasses everything from large-scale geological processes and structures to rocks and minerals found on and below the Earth's surface. We, geologists, use our knowledge of the Earth's history to understand how it has developed over time and how this affects our daily lives.“ Blilie is the product manager for some of Cegal’s geophysical software products and is one of over 40 geologists at Cegal.
Read about our Geoscience software here >
Geology plays an essential role in many areas, from building houses, roads, and infrastructure to oil and gas production. The Norwegian geology on the mainland, with significant differences in elevation and solid rocks, is a vital prerequisite for Norway becoming a hydropower nation. Geology is also a fundamental factor for other energy sources, such as wind and geothermal heat.
Blilie explains: "Geology is a diverse field encompassing several disciplines, including sedimentology, mineralogy, petrology, geomorphology, and geochemistry. Each of these subfields focuses on a different aspect of the Earth. Geologists use various technologies, techniques, and tools to collect information about the Earth. These include seismic surveys, drilling tests, ground-penetrating radar, satellite images, and geological maps. These tools help geologists visualize and interpret the geologic features of the Earth's subsurface and surface, which is crucial for a wide range of applications, from exploring and producing natural resources to environmental management and hazard mitigation.
Geology deals with the classification and description of the properties of rocks, the distribution of elements, minerals, and rocks in the Earth's interior, and, not least, knowledge of the processes behind it. Furthermore, the study of past organisms and the development of life is central.
Photo: NGU
Let's concentrate on the geology behind oil and gas production – petroleum geology. This knowledge is also fundamental when capturing and storing carbon dioxide (CO2), the so-called CCS (carbon capture and storage). We'll come back to that in a bit.
Sedimentary rocks are the prerequisite for us to extract oil and gas. Rocks are the solid materials that make up the Earth's crust, and there are three different types of rocks:
● Igneous rocks, or eruptive rocks, are solidified by a molten mass.
● The transformation of other rocks forms metamorphic rocks as a result of different pressure and different temperature.
● The hardening of sediments forms sedimentary rocks. The deposits are formed by weathering, breakdown, and deposition on the surface or by chemical processes and organic activity.
Igneous and metamorphic rocks are usually compact, while sedimentary rocks are porous and can have large voids.
Blilie says that on the Norwegian seabed, the Norwegian shelf, five main geological conditions make it so suitable for oil and gas production.
Porous rock, often sedimentary rocks, is one of the prerequisites. If it is possible to extract the oil and gas, it must be collected in a sedimentary reservoir rock. The assumption is that the rock is porous and permeable, meaning it has an airy and "spongy" structure that can act as a container for petroleum.
The formation of oil and gas is another prerequisite. Oil and gas are formed by organic material buried in sediment several million years ago. Plankton from the Jurassic period, 200-146 million years ago, is the basis for large parts of our petroleum deposits. Over time the plankton remains became converted into oil or gas under high pressure and high temperature in the source rock. A source rock is often dark or black shale with a high organic content.
The third prerequisite is something that keeps the oil and gas in place in the porous rocks. After the oil and gas are formed in the source rock and then flow into and are absorbed by the reservoir rock, it must be held in place by a dense, non-porous cap rock. Otherwise, the oil and gas will continue to flow out of the reservoir and disappear. A trap structure to create a container for the petroleum, often created by faults, is also an essential requirement for the accumulation of oil and gas, along with the correct timing of petroleum generation and expulsion relative to trap formation. An exploration geologist’s job is to evaluate these factors, follow the likely paths of the hydrocarbons from the source rocks and attempt to find out where sizeable accumulations of oil and gas may exist.
Blilie explains: “Correspondingly, to be able to store carbon dioxide, we need both a reservoir rock, a trapping structure, and a cap rock to ensure that the carbon does not flow out of the reservoir and disappear into the atmosphere. Therefore, our acquired petroleum geological knowledge is so important for CCS.”
Carbon capture and storage are essential for reducing greenhouse gas emissions and mitigating the effects of climate change. CCS is used to reduce emissions of greenhouse gases into the atmosphere, especially carbon dioxide, from significant points of emission sources such as power stations, steel mills, cement factories, and other industrial facilities. CCS involves three main steps: capture, transport, and storage of CO2.
First, CO2 is captured from the fluid gases using various technologies, such as chemical absorption, adsorption, or membrane separation. The CO2 is then transported from the source to a suitable storage location, which can be an oil well, a salt formation, or a geological basin under the seabed. Finally, the CO2 is injected into the storage site under high pressure, allowing it to be stored safely and permanently for centuries or more.
Recently, Cegal partnered with the Norwegian Geotechnical Institute (NGI) to develop innovative technology for CCS. The goal is to create solutions that contribute to a future with net zero emissions of greenhouse gases. The partnership combines NGI's geoscience expertise with Cegal's expertise in data management and technology for the energy industry.
Read the case: NGI and Cegal partner to advance carbon capture and storage technologies >
Pictured: Elin Skurtveit (research manager CCS, NGI), Kersti Ekeland Bjurstrøm (Chief Product Officer, Cegal), Kristoffer Norborg (Global Business Development Manager, Cegal), Dagfinn Ringaas (CEO, Cegal) and Thomas Langford (director offshore energy, NGI).
The new collaboration includes research and development of carbon dioxide storage technology and the development of business opportunities in the area. Cegal contributes software development and technology expertise to simplify current CCS processes in geological formations. NGI will contribute with its unique insight into and experience in reservoir archaeology, geotechnics, and geophysics.
Cegal will be a world-leading technology company for the energy industry and be an important contributor to the green shift.
Kristin Blilie, Cegal
- Contributing to developing CCS technology that makes it efficient and profitable to capture and store carbon is important. With Cegal's experience and expertise, we have very good prerequisites to make this happen, says Kristin Blilie in conclusion.