Contribution of CERGOP-2/Environment project to geokinematics of Central Europe

Transcription

1 Contribution of CERGOP-2/Environment project to geokinematics of Central Europe J. Hefty, A. Caporali and the CERGOP team: M. Becker, I. Fejes, L. Gerhatova, D. Ghitau, Gy. Grenerczy, D. Medac, G. Milev, M. Mojzes, M. Mulic, A. Nardo, P. Pesec, T. Rus, J. Simek, J. Sledzinski, M Solaric, G. Stangl, F. Vespe, G. Virag, F. Vodopivec, F. Zablotskyi EUREF Symposium 2007, London/England - June 6-9, 2007

2 Content Introduction Overview of CEGRN and the CERGOP-2 The CERGOP velocities and velocity field for Central Europe computation, analysis, interpolation and stochastic issues Tectonic structure of the region Strain analysis Discussion

3 CEGRN Central Europe Geodynamic Regional Network CEI (Central European Initiative) 11 Countries: Austria, Bulgaria, Croatia, Czech Republic, Germany, Hungary, Italy, Poland, Slovakia, Ukraine, Bulgaria CEGRN 2007: 19 Countries: CEI + Albania, Belarus, Bosnia Herzegovina, FYROM, Moldova, Romania, Serbia, Slovenia

4 CEGRN Structure after End of EU-Project CERGOP-2 Consortium of participating countries Steering Committee International Project Working Group Data Processing and Analysis Centers Study groups (CSG): CSG1: Investigation of tropospheric delays CSG2: CERGOP site quality monitoring CSG3: CERGOP reference frame CSG4: Standardization of data and processing centers CSG5: Permanent / epoch GPS CERGOP stations CSG6: CEGRN and height determination CSG7: CERGOP gravity network CSG8: Geotectonic analysis of the region of Central Europe CSG10: Monitoring of recent crustal movements Eastern Alps CSG11: Three-dimensional plate kinematics in Romania: Balkan Peninsula

5 CEGRN Structure Participating Institutes CEGRN Consortium Governing Board CGB Consortium Secretariat Steering Committee (4 member) CEGRN Network sites and Host Institutes CEGRN Data Center CEGRN Processing and analysis Centres USER COMMUNITY Project Study Groups, Universities, Res. Institutes, Organizations

6 Tectonic setting

7 BOR1 GRAZ JOZE KOSG LAMA METS ONSA PENC WTZR ZIMM AT01 CSAR GOPE GRYB LJUB MATE MOPI POTS SKPL SNIE STHO UZHD BRSK DISZ HFLK LVIV SOFI HOHE MACI SULP TUBO BUCA BZRG DRES GRMT HVAR KIRS MEDI SRJV UPAD VRAN WRO BOZI BUCU CSAN GILA HARM KAME LYSA MALJ PART POL1 SBGZ TARP UNPG UZHL VATR BASO BRAI CLUJ DUBR FUN3 FUND IAS3 PADO POLO SIBI SUCE TIMI TIS3 GRMS CEGRN Campaigns and Evolution 1994: 30 Sites / 11 Countries 9 Permanent stations 21 Epoch stations 2005: 19 Countries 44 Permanent stations 27 Epoch stations 18 New candidate stations Epochs per Site

8 CERGOP-2 Self Contained Permanent Site Remote installation Pole for equipment Underground antenna cable Pillar for Antenna WLAN connection to next access-point (5-10 km)

9 Main Objectives of CERGOP geokinematical investigations Network solutions at individual analysis centres and their combination Combination of repeated epoch networks, coordinate and velocity estimates Evaluation of accuracy and reliability of obtained information Modelling of regional intraplate 3D velocity field at millimetre level Velocity maps, regular grid velocities, deformations, geo-kinematical interpretations Evaluation of statistical significance of derived quantities Visualisation of products, geo-kinematical maps Strain analysis and detection of velocity changes for dynamical investigations and special study areas with national or regional densification networks

10 CEGRN Campaigns Campaigns Period Countries Sites CEGRN' May E + 9P CEGRN'95 29 May-3 June E + 13P CEGRN' June E+13P CEGRN' June E+20P CEGRN' June (extended network) 19P+38E CEGRN' June (extended network) 28P+23E CEGRN' June (extended network) 28P+23E CEGRN' June (extended network) 44P+50E CEGRN' June 2006 Only P GPS 44 P CEGRN' June (extended network) approx. 90 (40P+50E)

11 The CERGOP velocities and velocity field for Central Europe The input for velocity estimation are results from 8 epoch campaigns performed from 1994 to 2005 Besides the epoch sites, which are most important for the densification of the velocity field, the IGS and EPN stations in region are included to be rigorously aligned to ITRF2000 The campaigns from 1994 to 2001 were reprocessed in 2002 with improved models using BV42. These models are applied also for 2003 and 2005 Reprocessing with BV50 is in progress

12 Examples of coordinate evolution at some CEGRN sites (with APKIM2000 removed) (Vectors represent the horizontal movement of the reference mark during 10 years)

13 Examples of coordinate evolution at some CEGRN sites (with APKIM2000 removed) (Vectors represent the horizontal movement of the reference mark during 10 years)

14 Coordinates and velocity estimation features Selection of sites where coordinates and velocity are estimated: only sites where more than 3 relevant epoch coordinates are available and are covering at least by 4 years observation span In 2005 were 18 sites for which original monumentation from 1994 was unchanged Reference: ITRF2000 coordinates and velocity field, epoch Statistics: 1110 observations, 52 non-reference sites, 384 parameters

15 Combined solutions of CEGRN observing campaigns used for common coordinate and velocity estimation Observing campaign Epoch Number of sites in final solution Number of solutions used for combination RMS of unit weight CEGRN (10 P + 17 E) CEGRN (13 P + 23 E) CEGRN (13 P + 24 E) CEGRN (20 P + 25 E) CEGRN (23 P + 38 E) CEGRN (25 P + 30 E) CEGRN (31 P + 30 E) CEGRN (44 P + 51 E)

16 INTRAPLATE VELOCITIES ESTIMATED FROM CEGRN WITH 2σ CONFIDENCE ELLIPSES (ITRF2000 referred velocities minus APKIM 2000) Significant differences among accuracy of velocities Reasons: (1) time span of site reobservations (2) quality of station observations (3) number of epoch campaigns

17 VERTICAL VELOCITIES ESTIMATED FROM CEGRN WITH 1σ CONFIDENCE INTERVALS Generally no significant height changes are observed Relatively large values at DRES, VRN1, FUN3, GILA and HVAR have to be explained (antenna problems?)

18 Classification of CEGRN sites according the accuracy of coordinates and velocities Time span of observations years (20 CEGRN sites) σ ne of horizontal coordinates ~1.5 mm, σ up of height ~7 mm, σ vne of horizontal velocities ~0.4 mm/y, σ vup of velocity in height ~1.5 mm/y Time span of observations 5-9 years (24 CEGRN sites) σ ne of horizontal coordinates ~2.5 mm, σ up of height ~15 mm, σ vne of horizontal velocities ~0.8 mm/y, σ vup of velocity in height ~3 mm/y Time span of observations less than 5 years (16 CEGRN sites) σ ne of horizontal coordinates ~4 mm, σ up of height ~ 20 mm, σ vne of horizontal velocities ~1.2 mm/y, σ vup of velocity in height ~6 mm/y

19 Comparison of CEGRN horizontal intraplate velocities with other velocity estimates (ITRF, EPN) (Examples of sites where the coincidence is proved)

20 Comparison of CEGRN horizontal intraplate velocities with other velocity estimates (Examplesofsiteswheresomediscrepanciesare observed)

21 Interpolation of horizontal velocities from CEGRN Observed velocities with some local anomalies excluded (SNIE, PART, POLO) Interpolation method - Least squares collocation Interpolated velocities for grid points with 2σ ellipses Constraint for LSC covariance function interpolation does not change the stochastic features of observed velocities

22 Interpolation of intraplate velocities from combination of epoch CERGOP observations and EPN stations in Central Europe Sites with local anlomalies were excluded (SNIE, PART, KRAW) Good consistence beetween EPN and CEGRN intraplate velocity fields

23 Application of CERGOP velocity field for further sudies Interpolated velocities in regular grid larger than 1σ Surface dilatation /depression Surface shear deformation

24 Stress Map (Reinecker et al. 2005)

25 6.0 C(d) (mm^2) d (degree) -Measured velocities in the CEGRN campaigns, with APKIM 2000 (Drewes, 1998) velocities removed -autocorrelation of the velocities and scale wavelength -interpolated (least squares collocation) velocities

26 Principal directions of strain rate

27 Quantitative evidence of: Closing of Adria N- indentation in Friuli E- lateral extrusion in Tauern Stable Central Europe S- motion of Eastern Europe N-S dextral shear zone along meridian ~22? Small strain rates, except in Friuli/Dinarids

28 GPS Velocities and Densification in Hungaria 0.00 PENC-HVAR Fit Results Fit 1: Linear, Y=B*X+A Equation: Y = * X Number of data points used = 4 Average X = 2002 Average Y = Regression sum of squares = Residual sum of squares = 8.56E-006 Coef of determination, R-squared = Residual mean square, sigma-hat-sq'd = 4.28E Data from: EPN CEGRN HGRN Grenerczy, CERGOP-2, W.P10.3

29 Strain rate field Uniform principal strain rates in selected subnetworks. Average 95% confidence is 4-6 degree in azimuths (strain directions) and 2 ppb/yr in strain rate magnitude E u r a s i a E u r a s i a E u r a s i a Based on CEGRN observations E u r a s i a Data from: Adria Adria 45 Adria Adria Strain rate scale 10 ppb/yr Strain rate scale EPN CEGRN HGRN ppb/yr Grenerczy, CERGOP-2, W.P10.3

30 Pannonian basin contraction and inversion? - HGRN results N ~3-4 ppb/yr average uniform contraction rate ~1.5±0.4 mm/yr shortening over the entire basin ~E-W, NE-SW direction N SOPR KOSZ HOLL PENC BUDA NADA AGGT MISK SATO TARP DISZ N CSER CSAR N Baseline length change [m] [m] Grenerczy, CERGOP-2, W.P E 16 E 18 E 20 E E 24 E Time [yr] [yr]

31 Conclusion CERGOP 2: a project which has capitalized on previous experience (field/processing/analysis) by several European groups, data from several campaigns back to 1994, integration with EUREF/EPN and IGS Results confirm expectations, but also open new discussion areas: e.g. Pannonian Basin Interaction with neighboring plates (Anatolia, Africa): only at plate margins (velocity contrast) or also at a longer wavelength (pattern of the velocity flow)?

32 Thanksforyourattention!