Publication Date:
2022-05-06
Description:
The goal of this article is the illustration of the new functionalities of the VADASE
(Variometric Approach for Displacements Analysis Stand-alone Engine) processing approach.
VADASE was presented in previous works as an approach able to estimate in real time the
velocities and displacements in a global reference frame (ITRF), using high-rate (1 Hz or more)
carrier phase observations and broadcast products (orbits, clocks) collected by a stand-alone GNSS
receiver, achieving a displacements accuracy within 1–2 cm (usually better) over intervals up
to a few minutes. It has been well known since the very first implementation and testing of
VADASE that the estimated displacements might be impacted by two different effects: spurious
spikes in the velocities due to outliers (consequently, displacements, obtained through velocities
integration, are severely corrupted) and trends in the displacements time series, mainly due to
broadcast orbit and clock errors. Two strategies are herein introduced, respectively based on
Leave-One-Out cross-validation (VADASE-LOO) for a receiver autonomous outlier detection, and on
a network augmentation strategy to filter common trends out (A-VADASE); they are combined
(first, VADASE-LOO; second, A-VADASE) for a complete solution. Moreover, starting from this
VADASE improved solution, an additional strategy is proposed to estimate in real time the overall
coseismic displacement occurring at each GNSS receiver. New VADASE advances are successfully
applied to the GPS data collected during the recent three strong earthquakes that occurred in Central
Italy on 24 August and 26 and 30 October 2016, and the results are herein presented and discussed.
The VADASE real-time estimated coseismic displacements are compared to the static ones derived
from the daily solutions obtained within the standard post-processing procedure by the Istituto
Nazionale di Geofisica e Vulcanologia.
Description:
Published
Description:
id 1201
Description:
2T. Deformazione crostale attiva
Description:
JCR Journal
Keywords:
GNSS seismology
;
variometric approach improvements
;
real-time coseismic displacements
;
Central Italy 2016 earthquakes
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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