Conservation, Scanning and Digitization of Historical Geomagnetic Data Archives from Brazil

This interinstitutional effort of Brazilian research centers aims the cataloging, conservation, digitization and online availability of historical collections of geomagnetic measurements (set of magnetograms, associated with its correspondent books of baseline and scale values) acquired throughout the 20th century in Brazil by the Vassouras and Tatuoca Magnetic Observatories (states of Rio de Janeiro and Pará, respectively). In addition to the valuable historical significance represented by the preservation of this scientific heritage, it will be provided access to the digitized data for both the scientific community and general public by means of an online data repository. Developments achieved so far were related to the VSS datafiles, and can be considered as highly satisfactory: (i) a 'backup' geomagnetic imagery, comprising ~ 87% of the magnetograms (approximately 29,200 documents), 36% of the absolute values books (30 volumes) and 57% of baseline and scale values books (4 volumes); (ii) a high-resolution imagery, comprising ~ 13,870 magnetograms (about 40% of the total), and 10% of absolute measurement and scale value books; (iii) the development of the online repository for this project; and (iv) the onset of digitization step by means of the VSS high-resolution imagery