cope4bg2020.copernicus.bg
Втори национален семинар по програма „Коперник” на ЕС 28 юли – 6 октомври 2020 г., Онлайн семинар
U s i n g s a t e l l i t e S A R d a t a f o r r e g i s t e r i n g E a r t h s ’ c r u s t d e f o r m a t i o n s a f t e r e a r t h q u a k e s
Assistant Professor Hristo Nikolov
Space research and technology institute - BAS
Associate Professor Mila Atanasova
National institute of geophysics, geodesy and geography – BAS
• Introduction – motivation
• Data and method used
• Results
• Conclusions
O u t l i n e
Motivation – earthquakes are occurring constantly and are not possible
to predict it is recognized that any information on the size of this events
is important for the local and national authorities responsible for
mitigation of the post-event damages. It is of importance to establish
the locations of the ground displacements triggered by this catastrophic
events for large areas which can be used as indicator where the
infrastructure objects are expected to be more prone to damages. Main
task of this study is to show how the magnitude of the ground
deformations is registered and how displacement maps are produced.
I n t r o d u c t i o n
D a t a
• Satellite radar instruments deliver SAR data that are able to provide reliable information on the magnitude of ground motions in range of centimeters since they deliver strictly quantitative measurement. Such information is of extreme importance is assessing the consequences of natural or man-made disasters.
• In principle with repeat pass InSAR is used to extract quantitative information on the scattering objects from complex interferograms produced by two or more sets of mutually correlated complex SAR images of a same scene
• In this research presented are the results obtained after processing sets of SAR data by D-InSAR method in order to study the subsidence/uplift or lateral deformation caused by three seismic events that happened the region of Balkan peninsula.
M e t h o d
The conventional technique of DInSAR measures the surface deformation only in the slant-range direction (LOS).
Nov 26 2019 – Durres,
Albania Mw 6.4
E v e n t s
July 20 2017 – near the island
of Kos, Greece Mw 6.6
Oct 26 2018 – Zakynthos,
Greece Mw 6.7
R e s u l t s - K o s e v e n t
IFI June 12-24 2017 ascending Bperp=33.24 m
unwrapped IFI unwrapped IFI
IFI June 18 - 30 2017 descending Bperp=5.51 m
R e s u l t s - Z a k i n t o s e v e n t
Restituted orbits Precise orbits
R e s u l t s - D u r r e s e v e n t
R e s u l t s - D u r r e s e v e n t ( a s c e n d i n g o r b i t )
GAMMA ISCE
ASF DAAC 2020, contains modified Copernicus Sentinel data 2019, processed by ESA Hogenson, K., Arko, S.A., Buechler, B., Hogenson, R., Herrmann, J. and Geiger, A., 2016. Hybrid Pluggable Processing Pipeline (HyP3): A cloud-based infrastructure for generic
processing of SAR data. Abstract [IN21B-1740] presented at 2016 AGU Fall Meeting, San Francisco, CA, 12-16 December.
R e s u l t s - D u r r e s e v e n t ( a s c e n d i n g o r b i t )
GAMMA SNAP
R e s u l t s - D u r r e s e v e n t
misleading terrain contribution to presence of fringes in the wrapped phase of an IFI
R e s u l t s - D u r r e s e v e n t
Epicenters (red pins) – European-Mediterranean Seismological Centre
Faults (yellow lines ) – European Database of Seismogenic Faults
R e s u l t s - D u r r e s e v e n t
established were the minimum and maximum values for both orbits which resulted to be quite different – minasc= 0.02 m / maxasc=0.033 m mindesc=0.08 m / maxdesc=0.092 m.
R e s u l t s - D u r r e s e v e n t
Coseismic offsets at two GNSS stations (DUR2 & TIR2) at the East, North, Up components, respectively. Red dots represent the daily station position at each component. The station coordinates are approximately at: DUR2 (Lat.
41.3156° – Lon. 19.451°) and TIR2 (Lat. 41.3357° - Lon 19.8095°) (as in doi:10.3390/geosciences10060210 )
• Co-seismic DInSAR processing of radar is an additional source of information on Earth crust deformations after an earthquake event
• It is possible to obtain reliable information in short time after the event concerning large areas, which in some cases are inaccessible for in-situ surveys
• Trustworthy information about the real ground displacements is obtained only after the precise satellite orbits
• To determine the type of ground motion (E-W or vertical) both orbits are to be processed and merged
C o n c l u s i o n s
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