Spanish Central System

The two outcrops are located in an area at the northern edge of the Cenozoic Madrid basin, close to the junction between two mountain ranges, the Central System (SW-NE oriented) and the Iberian Chain (NE-SW oriented). Because of this configuration, the area is characterized by the presence of a variety of small scale and well exposed tectonic structures, which are ideal to be captured with a drone and represented as 3D models.

The geological information, as well as the pictures of geological maps and sections are taken from the following sources:

• "The Madrid Basin and the Central System: A tectonostratigraphic analysis from 2D seismic lines", by G. de Vicente and A. Muñoz-Martín (Faculty of Earth Sciences, Univ. Complutense of Madrid), in "Tectonophysics" 2013.

• "Relationships between Tectonic Activity and the Sedimentary infilling of the Cenozoic Madrid Basin - The Linking Area between the Spanish Central System and the Iberian Range", field trip led by Alfonso Muñoz-Martín and M. Josefa Herrero (Faculty of Earth Sciences, Univ. Complutense of Madrid) in June 2015.

The following geological section shows the transition between the Central System mountain range and the Madrid basin. The north-western part of the section shows the intense deformation due to the presence of the Huermeces and Baides thrusts. Further south-east, the section represents the sedimentary filling of the Madrid basin with very limited deformation.

This outcrop is located by the village of Huermeces de Cerro, in the province of Guadalajara,  130 km north-east of Madrid, Spain.

The thrust represented in this outcrop has pulled Late Cretaceous marine limestones on top Eocene continental limestones. The Eocene layers are overturned by the deformation and appear vertical in the outcrop.

The geometries of this tectonic structure have been interpreted using the software Move for structural interpretation (by Midland Valley).

Three surfaces have been modeled on top of the 3D model of the outcrop:

• Green Surface: Cretaceous carbonates, interpreted following the nearly horizontal strata that appear in the outcrop

• Orange surface: Eocene carbonates, interpreted following the vertical strata that appear in the outcrop and that represent the overturned portion of the layers

• Red surface: Huermeces thrust, interpreted along the major scarp in the topography.

These surfaces were exported from Move, combined with the 3D model of the topography using the software Blender, and finally uploaded to Sketchfab for their final display.

Here is the 3D model of the outctop , with interpreted geometrical surfaces that help visualize  the geology and the tectonic deformation.

The geological strata, seen in map view, are bent in a crescent shape, suggesting the presence of a gentle anticline with the hinge plunging towards north-east, as indicated by the geological map and similar to what is shown in the simplified model drawing.

This is the digital 3D model of the outcrop.

The plunging anticline has been highlighted with the orange surface, that was modeled following one of the geological strata that extends along the outcrop.

You can also see a video showing the model in action on YOUTUBE