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CORING THE CENOZOIC. Southern North Sea Basin drilling project. North Sea Basin. Epicontinental basin Continuous subsidence during the Cenozoic Due to regional uplift: shifting patterns of erosion and sedimentation Extensive delta formation in Neogene and Quaternary
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CORING THE CENOZOIC Southern North Sea Basin drilling project
Coring the Cenozoic North Sea Basin Epicontinental basin Continuous subsidence during the Cenozoic Due to regional uplift: shifting patterns of erosion and sedimentation Extensive delta formation in Neogene and Quaternary Excellent archive of climate change, resulting from thick sedimentary sequences Coupling land-sea evidence of global change
Coring the Cenozoic Cenozoic Global Climate Ice Sheets Northern Hemisphere Large Antarctic ice sheets Samll Antarctic ice sheets In the North Sea basin only parts of the Cenozoic record are studied in detail
Coring the Cenozoic North Sea Basin Always an open connection to the Atlantic in the North Former Seaways existed to the South and Southeast, forming pathways for the immigration of exotic elements into the NSB Sedimentary infill results from shifting erosion and sedimentation patterns and forms the response on climate change and regional tectonics (uplift) SPBA Atlas, 2010, Knox et al. Chapter 12
Coring the Cenozoic North Sea Basin Palaeogeography: Late Paleocene – Early Eocene SPBA Atlas, 2010, Knox et al. Chapter 12
Coring the Cenozoic North Sea Basin Palaeogeography: Mid Eocene – Late Oligocene SPBA Atlas, 2010, Knox et al. Chapter 12
Coring the Cenozoic North Sea Basin Palaeogeography: Miocene – Quaternary SPBA Atlas, 2010, Knox et al. Chapter 12
Coring the Cenozoic 3 POTENTIAL DRILLING SITES (onshore part of the Netherlands) Southern North Sea Basin, depth position top chalk (Danian) • SE Netherlands (Roer Valley Graben): High-resolution analysis of the Miocene and the Rhine-Meuse fluvial system. • B.NE Netherlands: Salt tectonics, human-induced seismicity caused by gas production. • C. NW Netherlands: Biostratigraphic record of the marine influence continuing into the Pleistocene. B C A
8 Ma peat formation 10 Ma fluvial development 28 Ma marine deposits Coring the Cenozoic A. Roer Valley Graben The Cenozoic is c. 1800 m thick and considerable Oligocene to recent subsidence allows a high-resolution analysis of the Miocene, and of the Rhine-Meusefluvio-deltaic system
Coring the Cenozoic B. NE-Netherlands The entire Cenozoic succession is relatively continuous but more condensed and affected by salt tectonics and where human-induced seismic activity caused by gas production can be monitored, coupling LOFAR
Coring the Cenozoic C. NW Netherlands The Cenozoic sequence is c. 1200m thick. Marine influence continues into the Early Pleistocene which promises a good biostratigraphical control over a yet badly known part of the succession. Interaction between Rhine-Meuse and Eridanosfluvial systems.
Coring the Cenozoic • Southern North Sea opportunities • The southern North Sea Basin provides a dominantly subsiding setting, where an up to 2000 m deep onshore borehole is planned to drill and date the near-continuous epicontinental siliclastic Cenozoic marine, near-shore, deltaic and fluvial sedimentary successions. • The main aims are: • To improve our understanding of the interplaybetween climate change, tectonics, sediment supply and loading and sea level variation. • To provide the first time ever Cenozoic stratigraphic reference sequence for the boreal realm that allows sedimentary and palaeoclimatic studies at unprecedented resolution, and serves as a regional ‘back-bone’ for numerous industry wells and seismic surveys providing 3D grip on sediment volumes and patterns. • To study the detailed structure, rate of change and lead-lag relations of key palaeoclimate events in the record during the last 65 million years, such as the Cretaceous-Palaeocene boundary, Early Eocene thermal optima (ETM 1 and 2), Early Oligocene glaciation and cooling, mid-Miocene climatic optimum, Mi1-7 glaciations, and the decline to and onset of Northern hemisphere glaciations. • To improve the insight in patterns and timing of regional uplift (e.g. Fennoscandian and Alpine regions) and the related patterns of change in erosion and sedimentation. • To get reliable data on the physical and chemical properties of the Cenozoic depositional wedge from the North Sea Basin. • To apply downhole geophysical arrays to further constrain the loci of weak tectonic and human-induced seismic events and monitoring acoustic noise to image the deeper parts of the Earth's crust using passive interferometry