Archive for March, 2011

Japan earthquake – IGS site displacements observed with magicGNSS

March 17th, 2011 by Álvaro Mozo

Some of the IGS stations placed in Japan are providing data after the magnitude 9.0 earthquake that hit Japan on March 11th, 2011. We have processed data from those stations with magicGNSS, to evaluate the site displacements due to the earthquake and its aftershocks. They are shown in the following graphic:

The pre- and post-earthquake coordinates have been computed with static PPP (GPS only, as most of the sites do not provide GLONASS data) using 1 day of data (March 10th and 15th, 2011, respectively).

Note that due to the aftershocks, the coordinates on March 15th may not be considered truly static, yet the results are considered very illustrative of the magnitude of the event.

The Japan earthquake observed by GPS and GLONASS

March 15th, 2011 by Álvaro Mozo

A 9.0-magnitude earthquake hit Japan on Friday March 11th, 2011 at 05:46 UTC. The epicenter was reported to be 130 kilometers (81 mi) off the east coast of the Oshika Peninsula, Tōhoku.

The National Astronomical Observatory in Mizusawa hosts a GNSS station which belongs to the IGS network. This station, labeled mizu, is located at around 140 km (87 mi) northwest of the epicenter, and provided GPS and GLONASS data at 1-sec rate until 06:00 UTC.

The following plots show the displacements of the mizu antenna coordinates during the earthquake, computed with magicGNSS’ GPS+GLONASS kinematic PPP. In both plots the positions are computed every second.

The IGS data from the mizu station for March 11th, 2011 used to compute the above plots have been made public in magicGNSS, so you can log into your account and process them yourself right now.