Lower Devonian plants are in Norway also known from the “Trondheimsleden” region on the west coast, and Devonian strata are known and analyzed by us in an earlier Master thesis concerning Hornhelen/Kvamshesten on the West Coast.
Other Devonian data points include the offshore Embla field in the Central Graben, also studied by us. A Devonian bitumen/oil from the Helgeland Basins is of the same type as the Beatrice oil from Moray Firth, Scotland and bitumen from the Orkneys which are also available for study.
It was at this time in Earth’s history that carbon capture by land plant was initiated and plants like at Røragen were the first to colonize land. Conditions of the planet was different then. It must be remembered that no “soil” existed at this time, and for that reason e.g., no erosion via rootlets and no meandering rivers.
The student will be part of an ongoing investigation with already one publication in print, planning for two more.
While early Devonian terrigenous lift forms are not well preserved at many locations world-wide, upper Devonian strata have been investigated by us on the Orkneys where laminate temporal lakes, intermittently connected to the sea, are more common.
Our world famous paleo-botanists who described the Røragen flora, did however not pay attention to the “paleo-depositional-environment” of the deposits, generally just briefly ascribing these to “lacustrine” conditions.
In this project we follow up the sampled shales and siltstones using the most modern geochemical methods (organic and inorganic) to shed light on the paleo-depositional environment, which was taken to be “lacustrine” for about 100 years, at that time without basically any chemical studies.
The Aims of this Study:
These includes for the student to learn modern organic geochemical techniques applied to paleo-depositional environmental studies, to reconstruct if the environment was saline, freshwater, saline of lagoonal-mixed. Specific biomarkers are used to shed light on life forms active in the environment at the time.
Geomarkers and temperature sensitive biomarkers are used to evaluate the maximum temperature of the sediment in the – at that time hinterland of the breakdown of the Caledonian mountain range to the West.
Specifically the student will learn to apply modern GC-FID, GC-MS methodology supported by fluid inclusions methodology and investigations of minerals using SEM to investigate the paleo-depositional environment for the deposits, the maturity of the rocks and the generation and preservation of hydrocarbon compounds we already have proven in the strata.
Temporal results suggest a great discrepancy between the assumed and reported “greenschist” metamorphic stage of the rocks, i.e., temperatures of at least 250 to 350oC, and the fact that hydrocarbon species, including biomarkers have survived in these strata since Devonian times. According to current models, hydrocarbon species as found in the strata, should simply not have survived at such high temperatures and for such extended time.
The understanding of this has implications to the “commercial-basement-understanding” i.e. depth of petroleum as a stable phase with relevancy, not only for “sub-salt” exploration in the Central Graben, but also for the petroleum in the deeper and hotter parts of the Vøring Basin and the Western Barents Sea.
Border conditions to the study of the paleo-depositional environment in the lower Devonian includes that the region of Norway was at that time just north of Equator in the tropical belt, and that the Moon was much nearer to Earth with obvious implications to more severe tidal forces. What was marine and what was lacustrine? What about rain patterns and fresh-water plumes?
Comparison with existing data and new measurements on the Devonian strata of the Orkneys, from 6609/11-1 (Helgeland Basin) and the Devonian extracts of the Embla Field, is possible (in house samples) for a more regional perspective, interesting also to the more international reader.
Mounting evidence suggests that deep and early migration of Devonian sourced oil could have occurred much more widely on the Norwegian Continental Shelf than previously assumed, with implications for both porosity preservation and “oil-saturation” of deep migration avenues and fault systems. Later generated oil would move with ease in such previously “oiled” strata.
It is believed that the project will shed light on the way “Norway” appeared in the Devonian time, with an international aspect including the Orkneys, and a data point from the Helgeland Basin offshore Mid-Norway. Relevant is also “early” life of land plants, how they spread and preservation of organic matter in high temperature metamorphic rocks.
If wanted, the student may participate in a summer sampling trip to Røragen-7 days, but this is a voluntary option.
Reconstructing the correct environmental and Petroleum System model for the Devonian strata will be done using the same methods and tool applied in all modern and contemporary forms of petroleum research. The relevance of these methods is obvious to also oil and gas exploration, where good “Petroleum System” models are needed.
Knowledge & Experience Gained for student- Learning Outcome:
Detailed knowledge of paleo-environmental methodology and research by use of the most contemporary analytical methods (hands on) and interpretations based on generating new data.
The methods applied to sedimentary rocks and oils from Vøring include extraction, Iatroscan TLC-FID, MPLC, GC-FID, GC-MS/MS and identification of biomarkers and geomarkers, statistical analyses and data evaluation in a geological context.
All methods are useful for environmental and organic geochemistry in general, including oil and gas research and source rock formation and maturity. Understanding of the carbon cycle and “Petroleum Systems” is obtained. The work is relevant for the energy companies working on reduced carbon as energy source i.e., the oil and gas industry.
Experience in writing international style publications is gain by potential participation as junior author in one of more ongoing publications. Data can be presented at an international meeting as a poster presentation.
The knowledge outlined above and a master exam in topics of wide application in all sorts of geochemical environmental studies, soil analysis, pollution-studies, understanding of the carbon cycle and the oil and gas industry.