## 4 Results
### Results of Combined ERT, DP HPT and Sediment Coring  
To gain detailed information on the stratigraphic composition of the shallow subsurface, we conducted ERT measurements followed by DP HPT logging. To finally calibrate the geophysical and DP results and to receive stratigraphical sequences, we retrieved sediment cores at the DP positions. ERT transect BIE ERT 1 (Figure 5) was conducted 25 m above the scar of the hillslope debris flow on a total length of 94 m in a southwest-northeast direction. Overall, apparent resistivity values range from 18 to 364 ohm.m. The inversion model shows a tripartite structure. The first part ranges from 0 to c. 40 m with high resistivities at the top followed by generally lower values and a further high resistivity unit below log location BIE HPT 1. A second part is visible until 64 m, characterised by higher values reaching the greatest thickness at DP site BIE HPT 2, intercalated by a unit of significantly lower resistivity emerging upward towards the northeast. The third part from 64 m until the end of the transect is characterised by high resistivities at the top followed by low values towards the base.  
All the DP HPT logs and sediment cores were drilled as deep as possible (Figures 6 and 7). Overall, 10 sediment units (SU) were described (Table 3). All cores show colluvial and/or periglacial slope deposits of different characteristics below the topsoil and above strongly weathered bedrock material. While reworked and weathered clay and sandstones dominate BIE 1 and BIE 2, BIE 3 contains reworked and weathered limestone material.  
DP log BIE HPT 1 is characterised by very low EC values in SU Ia and II, which slightly increase towards SU III. The weathered bedrock of SU IVa, which we reached by sediment coring, could not be penetrated with the HPT probe. HPT values show a distinct increase from SU II to SU III. In BIE HPT 2 and BIE 2 we reached the greatest depth with 5.58 m and 5.00 m, respectively. Both EC and HPT data trace coarser or more porous layers in the sedimentary sequence by low EC and low HPT values. The most significant decrease in EC occurs in SU VI, which is accompanied by the lowest HPT values of all three DP HPT logs. In sediment core BIE 2, SU VI is characterised by a dominance of sand and sandstone debris in a silty matrix. Towards the base, EC and HPT increase again. Compared to BIE HPT 1 and BIE HPT 2, BIE HPT 3 shows significantly differing characteristics. EC values show intensive fluctuations between 0 and 30 mS/min; HPT values are constantly low apart from some clayey layers in SU VII.  
Figure 5: Upper: depth section of ERT transect BIE ERT 1 (iteration 6, absolute error 1.4%) and position of DP HPT logs and sediment cores retrieved from right above the scerped ridge (cp. Figure 1). Lower: depth section with interpretation according to field observation and geological data (see discussion in Section 5).  
Figure 6: Photo of sediment cores BIE 1 (**upper**), BIE 2 (**middle**) and BIE 3 (**lower**). Ground surface upper left, coring base lower right of each core. Sediment units are described in Table 3.  
Figure 7: Sediment cores BIE 1 to 3 with DP HPT data (electrical conductivity, EC and hydraulic pressure (HP). Sediment units Ia–VII refer to description in Table 3 (see also Figure 5).