Methods in physical geography (study of surface processes) and geology (subsurface processes) are often applied separately. However the governing physical processes are strongly coupled so that an integration of these two disciplines provides a unique opportunity to gain an encompassing understanding of observations at the Earth's surface, while better constraining the controlling subsurface processes. Here we provide an example of such integration based on a case study, the Drentsche Aa brook valley (DA), onshore Netherlands. In the DA, surface observations (vegetation types, peat thickness, and groundwater pressures) are likely related to the occurrence of salt diapirs that warped overlying strata into a steep dome just 100-200 meter below the subsurface. A 3D geological model of the DA based on onshore 3D seismic data provides important context for observations made at the surface. By juxtaposing the information in smart visualizations, the spatial relationship between surface observations and shallow salt diapirs is straightforward. We suggest that deep regional groundwater flow is likely forced towards the surface by the occurrence of these impermeable structures, which results in high groundwater pressure and elevated temperatures, salt-water vegetation, and thick peat formation. These insights are important for the surrounding hydrocarbon fields, as the data show that a shallow regional seal is possibly leaking. In addition, we show that the physical geographic discipline can very much benefit from integration with geology and vice versa.
Presentation Date: Monday, October 15, 2018
Start Time: 1:50:00 PM
Location: 210A (Anaheim Convention Center)
Presentation Type: Oral