Seismic Hazards Pilot

2D displacement map derived from Sentinel-1 pixel correlation following the 25 April 2015  M 7.8 Gorkha, Nepal earthquake  and generated by the Remote Sensing Technology Institute of DLR. The Sentinel-1 data allowed to measure a negative range shift of about 0.8 meters, corresponding to a possible uplift of about 1 meter and an azimuth shift on the order of 1.8 meters. This is an absolute measurement derived from Sentinel-1 orbital geometry without any reference point on ground.  Courtesy of DLR.

2D displacement map derived from Sentinel-1 pixel correlation following the 25 April 2015 M 7.8 Gorkha, Nepal earthquake and generated by the Remote Sensing Technology Institute of DLR. The Sentinel-1 data allowed to measure a negative range shift of about 0.8 meters, corresponding to a possible uplift of about 1 meter and an azimuth shift on the order of 1.8 meters. This is an absolute measurement derived from Sentinel-1 orbital geometry without any reference point on ground. Courtesy of DLR.

The Seismic Hazards Pilot sets its objectives based on priorities elaborated through consultation with users and practitioners of satellite EO and geohazards. For instance, specialists of remote sensing and risk assessment defined their objectives and EO data requirements through an open review process in the framework of the 2012 International Forum on Satellite Earth Observations (the Santorini report) and Geohazards.

Main Pilot objectives are:
A. Support the generation of globally self-consistent strain rate estimates and the mapping of active faults at the global scale by providing interferometric synthetic aperture radar (InSAR) and optical data and processing capacities to existing initiatives (wide extent satellite observations)
B. Continue to support the Geohazard Supersites and Natural Laboratories initiative (GSNL) for the seismic hazard activities (satellite observations focused on supersites)
C. Develop and demonstrate advanced science products for rapid earthquake response (observation of earthquakes with low to intermediate magnitude, M>5.8)

The Pilot’s broader CEOS objective is to demonstrate how satellite EO can be used to improve geodetic monitoring of faults and the earthquake cycle, and provide scientific information to support the response to seismic events.

• To date the key successes of the pilot include a range of EO based products and derived publications. In particular a variety of terrain motion mapping products have been published following earthquakes, either in the context of the Geohazard Supersites (Event Supersites) or as part of the pilot’s Objective C). The following events occurred in 2015 have been investigated using EO data to map the ground deformation and model the seismic source parameters: the Nepal earthquake (April 2015), the Chile earthquake (September 2015) and the Lefkada, Greece earthquake (November 2015).

Further to this, the Seismic Pilot provided access to an innovative processing environment to support the user community with the Geohazards Exploitation Platform or GEP. The GEP is provided by ESA, and aims to facilitate collaborative work and support the exploitation of satellite EO using cloud processing to allow fast analysis of large EO data collections such as for instance Sentinel-1 data whose throughput is already 3 Terabyte per sensor per day. Since March 2015 the GEP has been made available to the geohazards community and 22 users are already on board including six specialists from the Seismic pilot. Today the GEP’s primary focus is on mapping hazard prone land surfaces and monitoring terrain deformation. It allows users to access and exploit large collections of ENVISAT, ERS and Sentinel-1A data hosted in the ESA clusters and in ESA’s Virtual Archive. In addition, Seismic Hazards Pilot users can further access data collections of ALOS-2, Cosmo-SkyMed and TerraSAR-X data contributing to the pilot.

The CEOS DRM group also provides a mechanism to gather input from the user community concerning observational strategies to support their thematic priorities. For instance, to support Objective A) the Seismic pilot has elaborated the mask of tectonic areas (regions that are deforming above a threshold rate of 10 nanostrains per year, taken from the Global Strain Rate Model v2.0 (http://gsrm2.unavco.org/)).

 

Seismic Risks Pilot Overview & Annexes