Navigation Links
Satellites show how Earth moved during Italy quake
Date:4/15/2009

Studying satellite radar data from ESA's Envisat and the Italian Space Agency's COSMO-SkyMed, scientists have begun analysing the movement of Earth during and after the 6.3 earthquake that shook the medieval town of L'Aquila in central Italy on 6 April 2009.

Scientists from Italy's Istituto per il Rilevamento Elettromagnetico dell' Ambiente (IREA-CNR) and the Istituto Nazionale di Geofisica e Vulcanologia (INGV) are studying Synthetic Aperture Radar (SAR) data from these satellites to map surface deformations after the earthquake and the numerous aftershocks that have followed.

The scientists are using a technique known as SAR Interferometry (InSAR), a sophisticated version of 'spot the difference'. InSAR involves combining two or more radar images of the same ground location in such a way that very precise measurements down to a scale of a few millimetres can be made of any ground motion taking place between image acquisitions.

The InSAR technique merges data acquired before and after the earthquake to generate 'interferogram' images that appear as rainbow-coloured interference patterns. A complete set of coloured bands, called 'fringes', represents ground movement relative to the spacecraft of half a wavelength, which is 2.8 cm in the case of Envisat's ASAR.

The first Envisat data, acquired after the earthquake on 12 April, were made immediately available to the scientists.

"We produced an interferogram just a few hours after the Envisat acquisition by combining these data with data acquired before the earthquake on 1 February. We were pleased that we were able to immediately see the pattern of the earthquake," said Riccardo Lanari of IREA-CNR in Naples, Italy.

The Envisat interferogram, as explained by Stefano Salvi from INGV's Earthquake Remote Sensing Group, shows nine fringes surrounding a maximum displacement area located midway between L'Aquila and Fossa, where the ground moved as much as 25 cm (along a line between the satellite's orbital position and the earthquake area).

"By using available 3D ground displacements from five GPS location sites around the affected area, we were able to confirm the preliminary results obtained with Envisat data," Salvi said.

The COSMO-SkyMed constellation, which is currently made up of three satellites, allows for frequent data. This means new interferograms can be calculated every few days.

The COSMO-SkyMed data together with the Envisat data and possibly SAR data from other satellites will ensure a dense sampling of the ground deformation around the L'Aquila area in the next months, which could make this earthquake one of the most covered by SAR Interferometry measurements.

To ensure all scientists are able to contribute to the analysis of the earthquake, ESA is making its Earth observation dataset collected over the L'Aquila area freely accessible with an innovative fast data download mechanism. The dataset will be continuously updated with the newest Envisat acquisitions.


'/>"/>

Contact: Mariangela D'Acunto
mariangela.dacunto@esa.int
39-069-418-0856
European Space Agency
Source:Eurekalert

Related biology news :

1. Satellites witness lowest Arctic ice coverage in history
2. UNCCD recognizes importance of satellites for combating desertification
3. Satellites help ensure efficient use of pesticides
4. ASU researchers use NASA satellites to improve pollution modeling
5. Satellites take sustainability to new heights
6. Satellites illuminate pollutions influence on clouds
7. Digital cameras, remote satellites measure crop water demand
8. Satellites helping aid workers in Honduras
9. Value of satellites recognized for conserving wetlands
10. ESA satellites focusing on the Arctic
11. ESA satellites flying in formation
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:11/15/2016)... 15, 2016  Synthetic Biologics, Inc. (NYSE MKT: ... on the gut microbiome, today announced the pricing ... of its common stock and warrants to purchase ... price to the public of $1.00 per share ... from the offering, excluding the proceeds, if any ...
(Date:6/27/2016)... Research and Markets has announced the addition of the "Biometrics ... The report forecasts the biometrics market ... CAGR of 12.28% during the period 2016-2020. The ... inputs from industry experts. The report covers the market landscape and ... a discussion of the key vendors operating in this market. ...
(Date:6/21/2016)... , June 21, 2016 NuData ... the new role of principal product architect and ... the director of customer development. Both will report ... technical officer. The moves reflect NuData,s strategic growth ... response to high customer demand and customer focus ...
Breaking Biology News(10 mins):
(Date:12/5/2016)... HAMILTON, Bermuda , Dec. 5, 2016 ... leading clinical-stage biopharmaceutical company focused on the treatment of ... of intepirdine for the treatment of Alzheimer,s disease will ... Disease (CTAD) Meeting on Friday, December 9, 2016 in ... CTAD will show results of both simple and complex ...
(Date:12/5/2016)... , ... December 05, 2016 , ... ... to soon resume cervical and lumbar disc production, company President, Jake Lubinski will ... who are implanting the AxioMed disc in Cologne and Karlsruhe to discuss the ...
(Date:12/5/2016)... NxGen MDx announced today that it brought its NxGen Informed ... been able to improve customer service through shortened turnaround times and at ... , CEO of NxGen MDx. ... A decrease in turnaround times by ... job opportunities at the Grand Rapid headquarters. The NxGen Informed ...
(Date:12/4/2016)... ... December 02, 2016 , ... A proposed five-year extension ... federally funded research and development is welcome news for the photonics community, say ... , As part of the National Defense Authorization Act (NDAA) compromise agreement finalized ...
Breaking Biology Technology: