This dataset accompanying the MOOC on soil applications contains an airborne hyperspectral HySpex image over the study site Demmin in Northern Germany which was recorded in October 2015. The surrounding area of Demmin is characterized by its glacial past and is largely used for agriculture. Here you can find relics of the ice age such as kettle holes - small, completely closed hollow shapes whose formation is attributed to the burial and subsequent thawing of an ice lens. Mostly overgrown nowadays by vegetation, SOC accumulates in these areas and higher contents are measured. The image dataset is fully pre-processed – all non-soil pixels are masked, the spectra were smoothed using a Savitzky-Golay Filter and transformed to first derivatives – and provided in BSQ format.
In addition to the HySpex image, this dataset contains a point data shapefile with 27 sampling locations, as well as information on the soil organic carbon (SOC) contents [g/kg]. The dataset is made publicly available as part of the Massive Open Online Course (MOOC) "Beyond the Visible - Imaging Spectroscopy for Soil Applications ", available from Spring 2023. Guidance on how to derive quantitative soil maps (SOC content) using the EnMAP-Box (QGIS plugin) are provided as videos at the HYPERedu YouTube channel, the soil MOOC course pages and the regression workflow documentation.
The dataset contains a subset of an airborne hyperspectral HyMap image over the Cabo de Gata-Nίjar Natural Park in Spain from 15.06.2005, and soil wet chemistry data based on in-situ soil sampling. The Cabo de Gata-Nίjar Natural Park is a semi-arid mediterranean area in Southern Spain, sparsely populated and with a range of landscape patterns. The soils in this area are developed on volcanic and carbonatic bedrocks and are highly variable in their textural and mineralogical composition, offering interesting spectral variability. The airborne survey was acquired during a DLR / HyVista HyEurope campaign. The image dataset is fully processed for atmospheric and geometric correction with PARGE and ATCOR and is provided as orthorectified reflectance in BSQ format. Spatial resolution is 5 m and spectral coverage is 0.45-2.45 μm with 12-17 nm spectral sampling.
In addition to the HyMap imagery, this dataset contains two soil reference datasets as CSV files, namely in-situ data for clay content and iron content.
The dataset is made publicly available as part of the Massive Open Online Course (MOOC) "Beyond the Visible - Imaging Spectroscopy for Soil Applications ", available from Spring 2024.
Guidance on how to derive semiquantitative and quantitative soil maps (clay and iron content) using the EnMAP-Box (QGIS plugin) EnSoMAP tool are provided as videos at the HYPERedu YouTube channel (https://www.youtube.com/@HYPERedu_GFZ/playlists) and the soil MOOC course pages (https://eo-college.org/courses/beyond-the-visible-imaging-spectroscopy-for-soil-applications/).
The data set contains chemical analyses of 32 different surface materials from the Bajoca feldspar mine in Portugal and their corresponding hyperspectral reflectance spectra. The field samples were collected in May 2019 within the LIGHTS (Lightweight Integrated Ground and Airborne Hyperspectral Topological Solutions) project. The goal in this project is to develop tools for hybrid data analysis of remote sensing data from different scales, geochemical and geological data for Li target area exploration (LIGHTS; Cardoso-Fernandes et al. (2020a,b & 2021) & Fabre et al. (in prep.)).
The hyperspectral data were acquired in the laboratory with the HySpex system in a range of 414 – 2498nm and on-site with the Spectral Evolution PSR+ 3500 handheld spectroradiometer (short “PSR+”) in a range of 350 – 2500nm. The sample spectra of 32 different surface samples are presented for both sensors systems. The resulting HySpex reflectance data are scaled from 0 – 10000, the PSR+ reflectance data are scaled from 0-1. Detailed information about the samples and geochemistry is presented in the data sheets.
The data set contains LIBS (Laser-Induced Breakdown Spectroscopy) emission spectra of 18 lithium-bearing minerals and their corresponding hyperspectral reflectance spectra. The data were collected within the research project LIGHTS (Lightweight Integrated Ground and Airborne Hyperspectral Topological Solutions, http://lights.univ-lorraine.fr/) which aims at developing a new exploration process for Li targets combining drone-borne hyperspectral data and field observations. Hyperspectral data were acquired with the HySpex system in a wavelength range of 414 - 2498 nm and are presented in a spectral library. Detailed information about the samples and area of spectral retrieval is presented in the data sheet below. The spectral library presented here expands the collection of spectral libraries including samples from rare-earth minerals, rare-earth-oxides (Koerting et al., 2019a) and copper-bearing minerals (Koellner et al., 2019) which are fully described in Koerting et al. (2021). These libraries aim to give a spectral overview of important resources and deposit mineralizations.
18 samples taken partly from the collections of the University of Potsdam (UP) and the Federal Institute for Geosciences and Natural Resources (BGR) and partly in the field during previous measurement campaigns were hyperspectrally measured and geochemically analysed by using a LIBS handheld analyzer. A description of the HySpex system in lab use can be found in Koerting et al. (2021).
The lithium-bearing mineral samples were measured without prior sample preparation as the surface of the minerals and the influence of the mineral structure were of interest (Figure 1). Figure 1 shows one HySpex scan of four lepidolite samples (Lep1, Lep2, Lep3, Lep4) displayed as a true color RGB image in order to show the untreated samples and the white reflectance (WR) panel needed for the hyperspectral measurements (WR 90%).