An introduction to causes and consequences of Cretaceous sea-level changes (IGCP 609)

2020-01-01
Wagreich, Michael
Sames, Benjamin
Hart, Malcolm
Yılmaz, İsmail Ömer
The International Geoscience Programme Project IGCP 609 addressed correlation, causes and consequences of short-term sea-level fluctuations during the Cretaceous. Processes causing several ka to several Ma (third- to fourth-order) sea-level oscillations during the Cretaceous are so far poorly understood. IGCP 609 proved the existence of sea-level cycles during potential ice sheet-free greenhouse to hothouse climate phases. These sea-level fluctuations were most probably controlled by aquifer-eustasy that is altering land-water storage owing to groundwater aquifer charge and discharge. The project investigated Cretaceous sea-level cycles in detail in order to differentiate and quantify both short- and long-term records based on orbital cyclicity. High-resolution sea-level records were correlated to the geological timescale resulting in a hierarchy of sea-level cycles in the longer Milankovitch band, especially in the 100 ka, 405 ka, 1.2 Ma and 2.4 Ma range. The relation of sea-level highs and lows to palaeoclimate events, palaeoenvironments and biota was also investigated using multiproxy studies. For a hothouse Earth such as the mid-Cretaceous, humid-arid climate cycles controlling groundwater-related sea-level change were evidenced by stable isotope data, correlation to continental lake-level records and humid-arid weathering cycles.
CRETACEOUS CLIMATE EVENTS AND SHORT-TERM SEA-LEVEL CHANGES

Suggestions

A process-based diagnostic approach to model evaluation: Application to the NWS distributed hydrologic model
Yılmaz, Koray Kamil; Wagener, Thorsten (American Geophysical Union (AGU), 2008-09-11)
Distributed hydrological models have the potential to provide improved streamflow forecasts along the entire channel network, while also simulating the spatial dynamics of evapotranspiration, soil moisture content, water quality, soil erosion, and land use change impacts. However, they are perceived as being difficult to parameterize and evaluate, thus translating into significant predictive uncertainty in the model results. Although a priori parameter estimates derived from observable watershed characteris...
A sequence stratigraphic approach to the depositional history analysis of the upper eocene sedimentary succession, northwest of the thrace basin, Turkey
Sünnetçioğlu, Mehmet Akif; Altıner, Demir; Department of Geological Engineering (2008)
This study investigates the depositional history of the Late Eocene sedimentary record in the northwest of the Thrace Basin in a sequence stratigraphic approach and estimates the contribution of regional tectonics, basin physiography and eustasy. Late Eocene sedimentary succession was analyzed in two third-order sequences based on two major data sets; seismic reflection and well data sets. Depositional Sequence-1, represented by progradational stacking patterns, comprises the coarse-grained “Hamitabat” turb...
An investigation of the flow and scour mechanisms around isolated spur dikes in a shallow open channel: 2. Conditions corresponding to the final stages of the erosion and deposition process
Köken, Mete (American Geophysical Union (AGU), 2008-08-05)
Large eddy simulation (LES) is used to investigate the flow around a vertical spur dike in a straight channel with equilibrium scour bathymetry and the scour mechanisms in the later stages of the erosion deposition process. The equilibrium bathymetry is obtained from an experiment conducted at the same relatively low channel Reynolds number (Re = 18,000). Flow visualizations are used to complement the information obtained from the numerical simulation. The present investigation demonstrates that large-scale...
Understanding tsunamis, potential source regions and tsunami-prone mechanisms in the Eastern Mediterranean
Yolsal, S.; Taymaz, Tuncay; Yalçıner, Ahmet Cevdet (Geological Society of London, 2007-01-01)
Historical tsunamis and tsunami propagation are synthesized in the Eastern Mediterranean Sea region, with particular attention to the Hellenic and the Cyprus arcs and the Levantine basin, to obtain a better picture of the tsunamigenic zones. Historical data of tsunami manifestation in the region are analysed, and compared with current seismic activity and plate interactions. Numerical simulations of potential and historical tsunamis reported in the Cyprus and Hellenic arcs are performed as case studies in t...
An investigation of the flow and scour mechanisms around isolated spur dikes in a shallow open channel: 1. Conditions corresponding to the initiation of the erosion and deposition process
Köken, Mete (American Geophysical Union (AGU), 2008-08-05)
The present study investigates the flow physics and the role played by the main coherent structures in the scouring processes around a vertical spur dike in a straight channel at conditions corresponding to the start (flat bed) of the scouring process. Large eddy simulation (LES) is performed at a relatively low channel Reynolds number (Re = 18,000), in the range where most flume studies with clear water scour conditions are conducted. Similar to these studies, the incoming flow is fully turbulent and conta...
Citation Formats
M. Wagreich, B. Sames, M. Hart, and İ. Ö. Yılmaz, “An introduction to causes and consequences of Cretaceous sea-level changes (IGCP 609),” CRETACEOUS CLIMATE EVENTS AND SHORT-TERM SEA-LEVEL CHANGES, pp. 1–8, 2020, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/45899.