How To Use The C-TAPE Website


The C-TAPE web site ( ) is intended to serve as a portal for researchers interested in searching and downloading spectral data and associated information, such as sample descriptions, compositional and structural data, housed at the Planetary Spectrophotometer Facility (PSF) at the University of Winnipeg.

There are two main pieces to the web site. The first is called “Mineral and Rock Sample Database: Planetary Spectrophotometer Facility”. It can be found under the “SAMPLE DIRECTORY” tab. It contains an ~1000 page document that provides information on how the sample-spectral database is organized. This document is organized somewhat randomly in the sense that many of the sections do not correspond particularly well to established mineral groups. This document and the sections have evolved as new samples have been added to this document over the years, usually by adding new sections as necessary to the end of the document. For most of the sections, and where available, the samples are organized in the following order: (a) sample descriptions, (b) X-ray diffraction data; (c) compositional data, and (d) spectral data. The first few pages of the document describe how the document is organized in more detail.

There are two major groupings: minerals and samples from specific localities or regions, as well as other miscellaneous groups of materials. To find specific types of samples, an easy approach would be to use a Search or Find function in a word processing program. The database is provided in both Microsoft Word and Adobe pdf formats (both of which have built-in search tools).

The second major piece of the web site is the spectral data. They are organized in the same way as the sections listed in the Table of Contents of the Mineral and Rock Sample Database. They are provided in Excel format with (hopefully) enough header information to enable users to understand and work with the spectral data. They are located under the “SAMPLE DATBASE” tab.The key link between the sample description document and the spectral data is the sample ID, usually located around line 4 of the spreadsheets and in bold blue typeface. The bulk of the spectral data are reflectance spectra, although increasing numbers of Raman and thermal emission data are being added to the database. The search functions inherent in Excel allow for database searching using whatever criteria the user may prefer. The hope is that by using Excel, we minimize the need for users to have to import and edit spectral data.