HRV Seismogram Archival Project: Scanned Images

The cleaned seismograms are placed in a mylar sleeve (thin flexible polyester cover) and are scanned using large-format scanner.

Initially, the seismograms are scanned using the VIDAR PRO TruScan Titan Atlas (courtesy of the Harvard Structural Geology and Earth Resources Group). The images generated by this scanner are saved in Adobe Photoshop (.psd) format. The front side of the seismograms (i.e., side with the recordings) is scanned in colour (24 bit) with 800 dpi resolution. The back side of the seismograms, where information such as type of instrument and component can be found, is scanned in grey scale (8 bit) with 400 dpi resolution. In order to enhance legibility of faint pencil writings, the contrast of the grey scale is set to zero, hence the images look grey.

The Department of Earth & Planetary Sciences acquired a new scanner, Contex HD Ultra i4250s, in 2013. The images obtained using this scanner has been saved in TIF format (.tif). The front side of the seismograms is scanned in colour (24 bit) with 1200 dpi resolution (with some exceptions), and the back side is scanned in grey scale (8 bit) with 400 dpi resolution.

Click on the year below to see image holdings.

In addition to seismograms recorded at the Harvard seismic station, recordings from seismic stations around the world are found in the collection. These include both originals and photocopies. Some of these have also been scanned.
Non-HRV Seismograms
WWSSN Microfiche Scans

Although have made every effort to recover, clean, and scan as many seismograms as possible, there are days where seismograms are simply missing or not available due to their poor conditions beyond hope.

Citation

• Ishii, M., Ishii, H., Bernier, B., & Bulat, E., 2015.
  Efforts to recover and digitize analog seismograms from Harvard-Adam Dziewonski observatory.
  Seismological Research Letters 86(1), 255-261.

Department of Earth and Planetary Sciences / Harvard University / 20 Oxford Street / Cambridge / MA 02138 / U.S.A. / Telephone: +1 617 495 2350 / Fax: +1 617 496 1907 / Email: reilly@eps.hartvard.edu