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.



On February 27, 2010, at 06:34 UTC, Chile was hit by an earthquake rating a magnitude of 8.8. The earthquake epicenter was offshore from the Maule Region, approximately 115 km (71 mi) north-northeast of Chile’s second largest city, Concepción.

The University of Concepción hosts the GNSS station called conz, tracking GPS and GLONASS satellites. conz survived the earthquake during several hours and continued recording data until 20:00 UTC.

The following plot shows the conz station displacement as a consequence of the earthquake. The plot shows the comparison of coordinates between two GPS+GLONASS Precise Point Positioning solutions, the first one using 5 hours of data before the earthquake, and the second one using 6 hours of data after the earthquake.

See also the IGS mail about predicted site displacement.

The PTTI conference finished today. Here is our presentation. This is a photo of our booth at the Exhibition:

The Precise Time and Time Interval (PTTI) conference will take place November 16-19 in New Mexico, USA.

GMV and INRiM (the Italian metrological institute) will be presenting a joint paper about how to synchronize a network of master clocks located worldwide and connected to GPS receivers, using the ODTS algorithm in magicGNSS. The PTTI ’09 program is here (see Paper 50, Thursday, Nov 19).

To support the paper and presentation, INRiM and GMV, with the collaboration of other timing labs in Europe and America, have set up an experiment to synchronize eight master clocks via GPS in near-real time. The GPS station names are: brus, ieng, ptbb, roap, sp01, sp02, spt0, and usn3.

The station data (hourly RINEX files) is uploaded every hour onto a dedicated magicGNSS account, and processed in ODTS automatically using the Scheduler. The reference station in ODTS is brus. ODTS processes data in batches of 2 days.

See the results on the Clock Synchronization Experiment for PTTI ’09 web page.

We have just presented our paper Orbits and Clocks for GLONASS Precise-Point-Positioning at the ION GNSS 2009 conference in Savannah, Georgia, USA (Session E3: PPP and Network-Based RTK 1, Thursday morning, September 24). The presentation is here, and the paper is here.

And this is a snapshot from out trip to Savannah: