**5. Conclusions**

The presented results indicate that quantitative colour measurements and spectral measurements during fieldwork can support stratigraphic delineation and interpretation of profiles in archaeological excavations. Depth-constrained hierarchical clustering of spectral data as well as of p-ED-XRF data should be considered a useful tool when analysing stratigraphic sequences quantitatively.

The discussed benefits of the multispectral image data suggest a huge potential of the spectral domain for automating stratigraphic delineation and interpretation and, likewise, render this process more traceable. Observed drawbacks show that we cannot offer a ready-to-use approach yet. In particular, the limited capabilities of the presented spectral imaging devices render the extensive analysis of sediment data not yet applicable for most excavations. Rather, additional on-site studies should be carried out to create standardised workflows. Image data that would involve spectral information of the same quality as our selective VIS-NIR measurements could prove to be as suitable for assisting stratigraphic interpretation as labour-intensive laboratory analyses. Quantitative colour measurements and spectral measurements, as performed in this study, may constitute an easy-to-apply, non-destructive additional step towards a fast and more traceable way of field documentation during archaeological excavations.

**Supplementary Materials:** The following are available online at http://www.mdpi.com/2571-9408/3/2/31/s1, **Online Resource 1** includes the image data used throughout this study along with the R-scripts that were used for image analyses. **Online Resource 2** covers the elemental concentrations of the sediment samples retrieved from a p-ED-XRF, as well as documentation of the processing workflow of these data. **Online Resource 3** comprises the VIS-NIR spectra of all sediment samples, recorded with a spectroradiometer (350–2500 nm). Additionally, the documentation of the pre-processing workflow is included.

**Author Contributions:** Concept and methodology devised by V.H. and B.S.; laboratory work and validation by V.H., P.H., M.N., B.S., and J.M.; formal analysis and software by V.H.; original draft of the manuscript prepared by V.H.; review and editing by B.S., M.N., P.H., J.M., and V.H.; supervision by B.S. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by the Cluster of Excellence EXC264 Topoi (The Formation and Transformation of Space and Knowledge in Ancient Civilizations, Research Area A; Deutsche Forschungsgemeinschaft (DFG) project number 39235742.

**Acknowledgments:** We thank the Cluster of Excellence EXC264 Topoi (The Formation and Transformation of Space and Knowledge in Ancient Civilizations, Research Area A) for funding this research. The publication of this article was funded by Freie Universität Berlin. Additional thanks is expressed to the Geography Department of the Humboldt-Universität zu Berlin for the possibility to use their spectroradiometer. Furthermore, we would like to thank Fabian Becker, Sebastian van der Linden, Jacob Hardt, and Jan Krause for their support. We thank the four anonymous reviewers for their detailed and valuable reviews, which helped to improve the manuscript substantially.

**Conflicts of Interest:** The authors declare no conflict of interest.
