Unveiling hydrocarbon formation and accumulation in the North Sea Basin through a new perspective of multi-spheric interaction
Science China Press
image:
The ranges of the north and south Permian basins are from Legler et al. (2005). The range of the Carboniferous foreland basin is from Ziegler (1988), including the present-day southern North Sea Basin, Baltic Sea, England, and Ireland.
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This study is led by Dr. Rixiang Zhu (Institute of Geology and Geophysics, Chinese Academy of Sciences) and his team, in collaboration with research groups of China, including the Research Institute of Petroleum Exploration and Development (China National Petroleum Corporation), China University of Petroleum (East China), and Peking University. By applying a new perspective of multi-spheric interactions within the Earth, the researchers reexamined the mechanisms of hydrocarbon formation and accumulation in the North Sea Basin. Located in northwestern Europe, the North Sea Basin is a region of significant importance for oil and gas production, accounting for 69.8 percent of the total oil and gas reserves of Europe, with strata rich in oil in the north and strata rich in gas in the south.
The researchers reconstructed the evolution of tectonics and processes of sedimentary filling in the basin, revealing that processes of deep thermal and dynamic forces drove block collision orogeny, mantle plume uplift, and intra-continental deformation. A series of tectonic events including post-Caledonian crustal extension, Variscan orogenic compression, mantle plume uplift, and subsequent thermal subsidence led to the formation of the Devonian rift basin, the Carboniferous foreland basin, and multiple stages of rift basin development since the Late Permian. Temporal and spatial variations, along with the superposition of systems of deposition, formed the framework of structure and stratigraphy observed in the basin today.
The study also analyzed how interactions among multiple spheres influenced the systems of petroleum in the basin, driving the distinct distribution of strata rich in oil in the north and strata rich in gas in the south. As the basin drifted northward since the Carboniferous, it passed through the Hadley and Ferrel Cells, contributing to the formation of coal and coal measures of the Upper Carboniferous as primary rocks of gas sources and marine shales of the Upper Jurassic Kimmeridge Clay as key rocks of oil sources, respectively. Tectonics, cycles of transgression and regression, oceanic currents, and evolution of climate controlled the distribution and properties of source rocks, reservoirs, and seals, resulting in the formation of a gas-rich system of the Carboniferous–Lower Triassic in the southern basin and an oil-rich system of the Upper Triassic–Paleogene in the northern basin.
Additionally, the study examines the potential of exploration of hydrocarbons in regions of mid to high latitudes. Comparative analysis reveals similarities between the basin of the Okhotsk Sea and the basin of the North Sea in development of tectonics, influences of climate, and favorable combinations of sources, reservoirs, and seals. These findings suggest that the basin of the Okhotsk Sea is a promising target for future discoveries of hydrocarbons. It also highlights the importance of the Ferrel Cell of mid latitudes in the enrichment of hydrocarbons throughout the history of geology.
Finally, the team emphasizes the role of artificial intelligence in advancing digital geological innovation and supporting the carbon-neutral utilization of resources, which contributes to a sustainable approach to energy exploration.
See the article:
Zhu R, Zhang S, Wang H, Wang X, Liu Y, Zhang W, Hao F, Jin Z. 2024. Multi-spheric interactions driven differential formation and accumulation of hydrocarbon resources in the North Sea Basin. Science China Earth Sciences, 67(11): 3397–3420, https://doi.org/10.1007/s11430-024-1421-8
Model of the evolution of the North Sea Basin
a) The terrestrial Old Red Sandstone dominated the Devonian sediments in the North Sea Basin. b) The Varisian orogeny occurred in the Late Carboniferous, forming a foreland basin at the front of the orogenic belt. The sediments in the North Sea Basin were mainly deposited in the continental and transitional facies. c) The Varisian orogeny and mantle plume uplift during the Early and Middle Permian led to overall uplift of the North Sea Basin, and a limited number of lacustrine sediments developed in the center of the basin. d) The Viking Basin began to form during the Permian and underwent a southward Zechstein transgression at the end of the Permian. The expansion of the Paleo−Tethys Ocean caused Gondwana to move away from the blocks surrounding the North Sea Basin. Concurrently, the Paleo−Tethys Ocean subducted at a low angle towards the southern part of the North Sea Basin, causing the lithosphere to begin to thin. e) During the Triassic, the Viking Corridor gradually opened up, and the Rhaetian transgression led to integration of the Paleo−Arctic and Paleo−Tethys oceans. f) In the Middle Jurassic, mantle plume uplift resulted in uplift and erosion in the central part of the North Sea Basin. g) The thermal subsidence after the uplift caused by the mantle plume formed trigeminal rift grabens and caused extensive marine sedimentation in the Late Jurassic. In the Late Cretaceous, the Alpine micro-block collided and proliferated in the southern part of the North Sea Basin, forming the Alpine orogenic belt. The connection between the North Sea Basin and Mediterranean was terminated. h) The uplift of the Iceland mantle plume since the Miocene led to uplift of the British Islands and Norwegian into land, basically forming the present structural framework of the North Sea Basin.
Multi-spheric interactions and the development of the petroleum systems in the North Sea Basin
a) Key geological events in the North Sea Basin (see main text for references). b) Global average temperature curve (Scotese et al., 2021), global oceanic 87Sr/86Sr curve (McArthur et al., 2020), Jurassic−Cretaceous oceanic anoxic events (Jenkyns, 2010), and major hydrocarbon source rocks in the North Sea Basin (see reference in the main text). c) Drift paths of the North Sea Basin and simulated annual precipitation at different latitudes (Li et al., 2022). d) Global sea level changes (Boulila et al., 2021) and key transgression events in the North Sea Basin (see references in the main text). e) Important source rocks, reservoirs, and seals in the petroleum systems in the North Sea Basin (see reference in the main text)
Map showing the tectonic units in the Okhotsk Basin and adjacent areas.
The base map is from the National Oceanic and Atmospheric Administration (NOAA) of the United States (https://www.ngdc.noaa.gov). The unit names are from He et al. (2016).
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©Science China Press
Journal
Science China Earth Sciences
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