New temporary broadband array: IRIS PASSCAL, Sweetwater
Purpose of the study: To establish a temporary mixed phase broadband seismic array with publicly open and available data that will facilitate new research. This was a 6 week study that began on March 11, 2014.
To establish a temporary mixed phase broadband seismic array with publicly open and available data that will facilitate new research. This was a 6 week study that began on March 11, 2014.
Several noise sources were present in the area, consisting of hundreds of wind turbines, hydraulic fracturing activity and active vibroseis trucks. Additionally, there was a consistent 3Hz signal observed in the area. There was also a limited amount of time available, as the project had not originally been budgeted for by PASSCAL.
Deployed in under 3 days using a direct burial technique, with a posthole auger, Nanometrics worked closely with the IRIS PASSCAL team to deploy a 25-station array. Nanometrics donated two field engineers, along with field equipment for 25 stations, to facilitate the speedy installation and provide training on the new direct burial technique. The direct burial technique was chosen for ease and speed of deployment.
Mixed Phase Array – 25 Stations
- 5 x Trillium 120 Postholes
- 25 x Field enclosures
- 25 x Solar panels
- 4 x Personnel
- 20 x Trillium Compact Posthole 20s Broadband Seismometers
- 25 x Centaur Digital Recorders
- 2 x Personnel
Deploying the Trillium Compact Posthole seismometers using this direct burial technique saved significant time and resources, without loss of performance, over older, vault style techniques that are susceptible to thermal instability and water ingress.
Link to IRIS open data set: http://ds.iris.edu/gmap/XB?timewindow=2014-2014