Developing Real-Time Strainmeter Data to Supplement GNSS and Seismically Determined Rapid Earthquake Magnitude Estimates

Date: 4/25/2019

Time: 06:00 PM

Room: Grand Ballroom

Under the most recent GAGE (Geodetic Facility for the Advancement of GEoscience) cooperative agreement with the NSF, UNAVCO was funded for another five years of operations of the borehole strainmeter (BSM) network originally built as part of the EarthScope Plate Boundary Observatory (PBO). This network, installed between 2005 and 2008, consists of 75 borehole strainmeters and 80 borehole seismometers along the Western US and into British Columbia. Additionally, 19 of these boreholes are co-located with GNSS monuments streaming real-time 1-Hz data. Borehole strainmeters are designed to detect variations in the strain field at the nanostrain level and can easily detect transient strains caused by aseismic creep events, episodic tremor and slip events, and record dynamic strains generated by seismic events. Operating for ~14 years, the GAGE strainmeter network provides a long-term, continuous, 1-sps record of deformation.

Recent work has shown that peak values in dynamic strains recorded by PBO strainmeters scale linearly with earthquake distance and magnitude (Barbour and Crowell, 2017). Unlike GNSS, where processing is required to generate displacements, the strains are measured directly, hence potentially reducing the complexity and latency of the observations. Also, the increased sensitivity of strainmeters, when compared to real-time GNSS-estimated displacements, suggests that real-time strain observations could provide constraints on earthquake magnitudes for events <M7.

Efforts have recently begun to upgrade our strainmeter dataflow from hourly downloads to real-time streaming. This effort will be made possible by leveraging the real-time infrastructure already in place for the NOTA (Network Of The Americas) GNSS network.

This presentation will summarize the current operational status of the GAGE strainmeter network, progress made in developing the real-time data flow, and a real-time data re-distribution mechanism.

Presenting Author: Mike H. Gottlieb

Authors