Where can I download historical sesimic data in CSV/Excel format for processing in R? I'm not familiar with these kinds of data sets but I'm looking for some data for a project I'm working on. Essentially I would like multiple time series of seismic data from different stations over different periods. Is this sort of data freely available somewhere in a friendly CSV format? 

Thanks for any help.

Luke
You can download seismic data in csv format at USGS, from past hour, past day, past week and past month.

If you wish to download ancient data you need to use the USGS API. There is a query option: format=csv.

This is an example of an URL that gives you seismic data in csv format from 2014-01-01 to 2014-01-02:

https://earthquake.usgs.gov/fdsnws/event/1/query?format=csv&amp;starttime=2014-01-01&amp;endtime=2014-01-02

User Kristjan shared a Python script to ask the API for all available data since 1900.