In the Netherlands subsurface data is legally arranged via The Basis Registratie Ondergrond, aka BRO: https://www.broinfobasisregistratieondergrond.nl/.
TNO manages this data. The data is i) distributed via interactive web portals:
- http://www.nlog.nl for deep offshore areas
- https://www.dinoloket.nl for land, and some data for offhsore areas
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- nl/ which is the official BRO site (Dinoloket, is a specific service of TNO, but hosts the same data)
There are four subsurface models as explained on on https://www.dinoloket.nl/en/explanation-subsurface-models. Each has its own WMS servie, which bundle many individual WMS layers:
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- The explanation of the layer/formation codes can be found here https://www.dinoloket.nl/nomenclator and in this Dutch report TNO 2012 R10991.
- bcc = basis of layer, tcc = top of layer, dcc = thickness of layer, breuk = interface.
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Two examples of GeoTOP formation "alt_onowa" via WMS in Google Earth: Formatie van Naaldwijk, Laagpakket van Walcheren, gelegen boven Formatie van Naaldwijk, Laagpakket van Zandvoort