Written by Julie Elliot and Jim Normandeau
30 December 2019
On November 30, 2018 a magnitude 7.1 earthquake struck just north of Anchorage, Alaska and caused over $75 million in damage to private and public facilities. The earthquake took place in the upper part of a subducting slab where the slab may be bending downwards, and early indications suggest that the event may have been related to stresses caused by this plate bending.
In the weeks and months following a large earthquake, slip and deformation can continue to take place along a fault and in the surrounding regions. To better understand the post-earthquake deformation, this study places five continuous GNSS stations around the earthquake epicenter and makes campaign GPS measurements at a number of benchmarks in the area. The new stations fill in a gap in the existing network of NOTA and other continuous GNSS stations. The Anchorage earthquake occurred within a region that has experienced multi-year slow slip events, raising the potential for triggered transient events. Data from this study will be used to learn more about slip behavior along the Alaska subduction zone and improve constraints on regional seismic hazards.
UNAVCO was tasked with the installation of the 5 continuously operating GNSS stations in the project area. Installation included purchasing of all necessary materials and supplies, in addition to providing Septentrio PolaRx5 GNSS equipment from the UNAVCO receiver pool. Due to delays beyond staff control, the first 4 of the 5 stations were installed in July, 2019. In November 2019, a second trip was made to install the 5th and last station. The cGNSS stations for the Alaska RAPID array consist of a short driven braced monument, 16 100Ah batteries and three 100 watt solar panels to keep the stations running through the Alaskan winter.
Last modified: 2020-01-28 22:51:35 America/Denver