Papers by J.C. Doornenbal
Kombrink, H., Doornenbal, J.C., Duin, E.J.T., Den Dulk, M., Van Gessel, S.F., Ten Veen, J.H. & Wi... more Kombrink, H., Doornenbal, J.C., Duin, E.J.T., Den Dulk, M., Van Gessel, S.F., Ten Veen, J.H. & Witmans, N.
A seismic velocity model is necessary to map depth and thickness of subsurface layers interpreted... more A seismic velocity model is necessary to map depth and thickness of subsurface layers interpreted from seismic reflection images. We have built a seismic velocity model (VELMOD-1) for the entire Netherlands area, both onshore and offshore, using non-confidential data (sonic logs, time-depth pairs, lithostratigraphic marker depths and downhole position data) of 720 boreholes in DINO -National Geoscientific Portal, and a preliminary isochore map (in seismic traveltime representation) of the layer of the Zechstein Group. The model is based on the V int -z mid method applied to the following lithostratigraphic layers: Lower, Middle and Upper North Sea groups; Chalk Group; Rijnland Group; Schieland, Scruff and Niedersachsen groups; Altena Group; Lower and Upper Germanic Trias groups; Upper Rotliegend Group; and Limburg Group. Per layer, the linear least squares approximation, applied to V int as a function of z mid , provides parameters V 0 and K for a linear velocity function V(z) = V 0 + K · z. In VELMOD-1, K is constant, at least at the scale of structural elements, whereas V 0 varies with location. At borehole locations, V 0 is calibrated such that traveltime through the layer according to the linear velocity model equals the traveltime according to the borehole data. A kriging procedure is applied to the calibrated V 0 (x,y)-values resulting in an estimated V 0 -value at any other location. The model V 0 -values were determined on an areal grid with cells of 1 km × 1 km. On the same grid, kriged interval velocities constitute the model for the Zechstein Group. These interval velocities stem directly from interval velocities at borehole locations; at other positions they are also dependent on the thickness (in terms of seismic traveltime isochores) of the layer of the Zechstein Group. Maps are presented of the distributions of both V 0 and its standard deviation for two layers: that of the Chalk Group and that of the Lower and Upper Germanic Trias groups.
This paper presents depth maps for eight key horizons and seven thickness maps covering the onsho... more This paper presents depth maps for eight key horizons and seven thickness maps covering the onshore and offshore areas for the Late Permian to recent sedimentary section of the Netherlands. These maps, prepared in the context of a TNO regional mapping project, are supported by nine regional structural cross sections and a table summarizing the timing of tectonic activity from Carboniferous to recent. These new regional maps enable the delineation of various structural elements but also reveal the development of these elements through time with improved detail.
This paper presents depth maps for eight key horizons and seven thickness maps covering the onsho... more This paper presents depth maps for eight key horizons and seven thickness maps covering the onshore and offshore areas for the Late Permian to recent sedimentary section of the Netherlands. These maps, prepared in the context of a TNO regional mapping project, are supported by nine regional structural cross sections and a table summarizing the timing of tectonic activity from Carboniferous to recent. These new regional maps enable the delineation of various structural elements but also reveal the development of these elements through time with improved detail. Since the latest Carboniferous the tectonic setting of the Netherlands changed repeatedly. During successive tectonic phases several pre-existing structural elements were reactivated and new elements appeared. The various identified regional structural elements are grouped into six tectonically active periods: Late Carboniferous, Permian, Triassic, Late Jurassic, Late Cretaceous and Cenozoic. This study demonstrates that many ...
Proceedings 76th EAGE Conference and Exhibition 2014, 2014
ABSTRACT In 2011, TNO-GDN concluded a 5 year geological mapping of the Netherlands Continental Sh... more ABSTRACT In 2011, TNO-GDN concluded a 5 year geological mapping of the Netherlands Continental Shelf. In this project all public data from hydrocarbon exploration were used resulting in a major update of the dataset and a variety of deliverables available at www.NLOG.NL. The stratigraphy of more than 400 wells has been re-examined and amended where necessary. 2D and 3D seismic surveys were re-interpreted and new velocity models were used for time-depth conversion of the interpretations. This resulted in a structural model from base Zechstein to base Neogene. Also 30 reservoir intervals were added to the model. For the offshore area around 3800 faults were interpreted. The offshore faults where the first to be stored in a spatial fault database. Apart from detailed spatial information, all faults are also labelled with fault-kinematic-, geomechanic- and dimensional properties. This database will soon become publicly available. The uncertainty related to interpretation and data-processing has been evaluated. This resulted in maps showing the standard deviation for the depth of the main stratigraphic intervals. Based on these new subsurface mapping results a new unambiguous- and data-driven classification of structural elements is proposed that reflects the coupling between the different stratigraphic superpositions encountered and the complex tectonic evolution.
Pursuant to a new law that will become effective in 2015, DINO, the national Dutch subsurface dat... more Pursuant to a new law that will become effective in 2015, DINO, the national Dutch subsurface database operated by the Geological Survey of the Netherlands, is to become an official government register (a 'key register' / basisregistratie). In facing the responsibilities associated with this new status, the Survey is reconsidering and redesigning its operation and in that process a new, or at least sharper picture is emerging of geological surveying in the future.
Proceedings of Middle East Oil Show, 1991
ABSTRACT Over the last ten to twenty years, geological surveys all over the world have been entan... more ABSTRACT Over the last ten to twenty years, geological surveys all over the world have been entangled in a process of digitisation. Their paper archives, built over many decades, have largely been replaced by electronic databases. The systematic production of geological map sheets is being replaced by 3D subsurface modelling, the results of which are distributed electronically. In the Netherlands, this transition is both being accelerated and concluded by a new law that will govern management and utilisation of subsurface information. Under this law, the Geological Survey of the Netherlands has been commissioned to build a key register for the subsurface: a single national database for subsurface data and information, which Dutch government bodies are obliged to use when making policies or decisions that pertain to, or can be affected by the subsurface. This requires the Survey to rethink and redesign a substantial part of its operation: from data acquisition and interpretation to delivery. It has also helped shape our view on geological surveying in the future. The key register, which is expected to start becoming operational in 2015, will contain vast quantities of subsurface data, as well as their interpretation into 3D models. The obligatory consultation of the register will raise user expectations of the reliability of all information it contains, and requires a strong focus on confidence issues. Building the necessary systems and meeting quality requirements is our biggest challenge in the upcoming years. The next step change will be towards building 4D models, which represent not only geological conditions in space, but also processes in time such as subsidence, anthropogenic effects, and those associated with global change.
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Papers by J.C. Doornenbal