Repository for Electromagnetc Data
Summary
Electromagnetic (EM) methods in geophysics are used to probe the Earth's deep interior for its electrical conductivity distribution through EM induction. This repository contains such data sets, mostly collected with magnetotellurics (MT) experiments. MT is based on EM fields generated by natural processes in the Earth's atmosphere and magnetosphere. But the repository also contains data from Controlled Source Electromagnetic (CSEM) projects, for which man-made EM sources are used.
The principle form of data in the repository are time-series of EM field components acquired with heterogeneous sets of sensors, recording instruments, and variable sampling rates. It is the main purpose of this archive or repository to provide the links between the data and their physical meaning by means of meta-data. To achieve this, the repository is organized as a combination of data files and associated meta-data in a folder (directory) structure, with the data files being sorted into subfolders (see Figure above).
Meta-data are provided as XML (Extensible Markup Language) formatted files. The MT repository was originally developed to archive data collected with instrumentation provided by the Geophysical Instrument Pool Potsdam (GIPP) of the German Research Centre for Geosciences - GFZ. GIPP instruments are provided to the international research community free of charge but with the obligation to archive and eventually publish the data. Therefore, the archive contains data of almost all projects carried out by the Geo-Electromagnetic and magnetotelluric working groups of GFZ Potsdam, together with projects from external universities and organizations also using GIPP instruments.
Documentation and Data
Users wishing to use the EM data repository should prepare their data following our guidelines. It is essential, for example, to clean a data set before archiving. Keep only those data, which are useful for data processing, and remove data from test runs, etc. The data must be organized in the underlying folder structure of the repository and meta-data for a project must be supplied.
Structure, organisation and definition of the electromagnetic data repository is described in detail in the scientific technical report below:
- The electromagnetic data repository of the Geophysical Instrument Pool Potsdam: Ritter, 0., Munoz, G., ..., Scientific Technical Report, xxx. (<-- link to landing page)
- You can browse the report directly or download a .pdf formatted document.
Data examples (a demo data repository) and code snippets to access the data and meta-data files are publicly available via GFZ's Gitlab server:
- Download demo repository and code snippets
A detailed description of the formats for the (time-series) data and the meta data is available as a scientific technical report:
- The EMERALD Format for Magnetotelluric Data is described in detail in: Ritter, O., Klose, R., Weckmann, U. (2015): EMERALD Data Format for Magnetotelluric Data, Scientific Technical Report - Data; 15/08, Potsdam: Deutsches GeoForschungsZentrum GFZ. DOI: http://doi.org/10.2312/GFZ.b103-15082
The GIPP Experiment and Data Archive is the platform for long-term archiving of geophysical experiment data and its supply to users. It contains metadata of all experiments supported by the "Geophysical Equipment Pool Potsdam" (GIPP) as well as data from active seismic and magnetotelluric field measurements.