Data file format


I would like to use the data from my shake for analysis in the software Geopsy. It accepts miniSEED format files, but when I try to load the data files that I have downloaded from my shake I get lots of 10 second wave forms. It appears that none of them have a specific timestamp. I imagine that I need to concatenate them into one single waveform. Please could you give me some advice around this subject?

Below is a table in Geopsy showing the data that is contained in a file that I downloaded from the FDSNWS to see if there was something different, but my own data displays in the same manner.

Hi Alan:

It does not look like anyone in the community has experience with Geospy. Maybe you can send an email to the Geospy mailing list (if there is one) and include the miniSEED file to see if they have any insights.

Please let us know what you learn.


I just found this:


i can give more information here, i think.

what your output tells me is that the geopsy software is reading each mini-SEED data packet, but not concatenating them internally. mini-SEED format is a simple (!) structure of header data (fixed size) followed by the data points themselves, in a compressed format, where the size of the data portion is fixed, while the number of data points is variable (due to the compression algorithm).

the software is responsible for both:

  1. decompressing the data points into memory
  2. concatenating all the data packets into a single stream of data, stored to memory, to be available for the end-user to do any processing on it.

without knowing this package myself, from what i see, and from what you say, it is not doing this.

as branden suggests, you should engage with the geopsy group and get their feedback on how this is supposed to work with their software.

hope this helps,



Thank you both for your replies. You’ve cleared up some questions that I had surrounding the data and I know which direction to take now.

One further question though. The miniSEED files from the shake have a number as a suffix, which I take is the day of the year. Why are they not further suffixed with the .msd file type?

Thanks again,

Alan, this is because the file naming in the data archive on the Shake has been constructed to conform to SeedLink’s Simple Data Structure (SDS). Read more about SDS here:

MiniSEED files can have many extensions, .ms, .msd, or .mseed just to cover a few. Most that get put into a data structure like SDS are not given an identifying extension because it’s assumed that they will be the only filetype in that structure. There’s no reason you couldn’t add the extension yourself after downloading if you wish.