Virtual field sites at the UNESCO Geopark Serra da Estrela (Portugal)

Virtual field sites are increasing in popularity beyond classrooms. Also, field investigations greatly benefit from DGPS-referenced 3D models. We show a selection of field sites at the UNESCO Geopark Serra da Estrela (Portugal) and how they were implemented into field research. In detail, the advantages of high-definition virtual models of tors, i.e., large residual vertical rocks that are still enrooted in bedrock, were explored in the modeling of the recently conceived tor exhumation approach (TEA; Raab et al., 2018) that can trace surface degradation over a multimillennial period within the landscape of interest. The TEA uses in-situ terrestrial cosmogenic nuclides (TCNs) to surface exposure date (SED) along the surfaces of tors.

Animated tors of two endmember sites, formerly glaciated and non-glaciated, contributed to derived continuous surface denudation variations covering the last ~200 ka and revealed glacial retreat dynamics in good detail. Higher isotope contents, thus, surface exposure ages were found in the non-glaciated area. In the formerly glaciated site, the ice margin distance correlates with the isotope signature of the tors. Higher elevation tors have experienced mass wasting and water erosion during the transition from a cool, moist, oceanic-Mediterranean climate. There, the younger rock surfaces have a higher chemical weathering degree than older surfaces at the non-glaciated site.

In summary, we provide freely available 3D field sites coupled with an extensive geomorphological study of these landscape features.