Hi Ed - Unfortunately, it depends on the station. Most of the data gaps originate with a radio telemetry problem, but there are many sources to this problem, like rime ice on antennas, or partial or complete equipment failures. Less common causes of gappy data include seismic data acquisition system (Earthworm) failures or misconfiguration, receive facility failures, and other network issues (internet outages, etc..). We are definitely tracking our data and our data outages, and addressing the issues that we can address. Thanks, cheryl Hello AVO, I hope your summer field work projects were successful. However the main reason for my email is an inquiry about the webicorders. Can anyone give me a brief explanation for the data gaps in nearly all the webicorders? Thanks very much for your time and any information. Sincerely, Ed Marker Kenai