Location description

A glance at the general geological map of Germany makes it clear that the eastern ridges of the Reinhardswald are formed from hard rocks of the Middle Bunter Sandstone, the depression in which Frankenhausen is located from the soft mudstones of the Upper Bunter Sandstone (Röt) - partly covered with loess - and the adjacent plateau to the west from limestones of the Lower and Middle Muschelkalk. The slightly hilly open depression lying between the plateaus to the north of the Kassel Basin stretches from Hofgeismar to Trendelburg and is referred to as the Hofgeismar Rötsenke in the natural landscape classification.

If we now zoom in on Frankenhausen and enlarge the geological map to a scale of 1:25000, the range of geological mapping units expands. In addition to Röt (so) and Löß (Lö), there are a total of 6 smaller basalt cones east of the main road and the Jungfernbach stream, some of which are surrounded by tertiary sands (Eocene). East of the railroad line, the rising slopes are again formed by red sandstone. Tertiary quartzites up to block size can be found sporadically, but can be found on the entire map sheet.

The results of the soil estimation are available, which are mapped at a scale of 1:2000. The soil numbers range from 25-82, with areas with soil numbers between 55-75 accounting for a large proportion of the area. The predominant soil type is parabrown loess. Pelosols can be found on some of the hilltops and colluviosols in the hollows.

In order to find out more about the soils and the current supply status, the Soil Science Department (Prof. Wildhagen, Department 11) carried out extensive soil mapping in a 50 m grid of all areas. In addition, two permanent soil observation plots were set up at representative locations, which were intensively sampled and analyzed and will be examined again at regular intervals in the future to determine long-term soil changes.

The soil profiles were described at approx. 1200 grid points on a 1m deep drill core (Pürkhauer) in accordance with the mapping instructions and the following data was recorded for each horizon: Horizon name, depth, texture, stone content, humus content, RedOx features, stratigraphy, carbonate content and any anomalies. A soil type was determined from the horizon sequences. After mapping, soil samples were taken in a radius of 20 cm around the borehole on arable land from a depth of 0-30 cm (grassland 0-15 cm) and analyzed for the following parameters: _Ct, _Nt, _P2O5 and _K2O(CAL), Mg (_CaCl2), pH value (_CaCl2) and occasionally _CaCO3 (Scheibler).

Profiles were excavated and described by students in several mapping practicals as guide profiles for the area mapping. A soil type map for the domain is to be compiled in combination with the borehole descriptions and the soil estimate data as well as the terrain model yet to be created.