NEW_Accomplishments.indd - IRIS

SURFACE OF THE EARTH: GLOBAL STUDIES
2006 IRIS 5-YEAR PROPOSAL
PASSCAL Experiments in Central Europe Target Lithospheric Structure
G. Randy Keller, Kate C. Miller • University of Texas at El Paso
Marek Grad • University of Warsaw, Poland
Alexander Guterch • Polish Academy of Science
Central Europe has experienced a complex tectonic history that dominated by
the accretion of terranes to the rifted margin of Baltica that extends through central
Poland (TESZ – Trans European Suture Zone) and formation of the Alps, Carpathians,
and Pannonian basin (Figure 1). Beginning in 1997, Central Europe has been
covered by an unprecedented network of seismic refraction experiments (Figure 2).
These experiments (POLONAISEʼ97, CELEBRATION 2002, ALP2002, and SUDE-
TES 2003) have only been possible due a massive international cooperative effort.
They along with the BOHEMA and ALPASS teleseismic experiments are providing
exciting new insights into
the structure and evolution
of the lithosphere in this
complex region.
The CELEBRATION
2000 experiment was the
most ambitious of these
projects and included 147
shots recorded by 1230
Figure 1. Tectonic map of Central Europe. USB
– Upper Silesian block; HCM – Holy Cross Mountains;
TESZ – Trans-European Suture Zone.
seismic stations forming, during three deployments that resulted in an
array of profiles whose total length is about 5400 km. The velocity model
derived for the longest profile CEL05 (1420 km; Figure 1) is shown in
Figure 3 and displays large variations in structure. In the Pannonian part of
the profile, crustal structure is relatively simple. The Moho lies at a depth
of only 24-25 km. The most complicated structure is observed in the transition
from the Pannonian basin, through the Carpathians, and across the
TESZ and margin of the EEC (East European Carton or Baltica). In this
area, the sedimentary cover with low velocities (Vp < 5.5 km/s) reaches a
depth of about 20 km, and the Moho deepens to about 50 km.
Figure 2. Index map showing the locations of major seismic
refraction experiments in Central Europe.
Guterch, A., M. Grad, H. Thybo and G. R. Keller, POLONAISE
ʼ97 – an international seismic experiment between Precambrian
and Variscan Europe in Poland: Tectonophysics, 314,
p. 101-121, 1999.
Keller, G. R., and R. D. Hatcher, Jr., Some comparisons of the
structure and evolution of the southern Appalachian-Ouachita
orogen and portions of the Trans-European suture zone
region: Tectonophysics, 314, p. 43-68, 1999.
Grad, M., S. L. Jensen, G. R. Keller, A. Guterch, H. Thybo, T.
Janik, T. Tiira, J. Yliniemi, U. Luosto, G. Motuza, V. Nasedkin,
W. Czuba, E. Gaczynski, P. Sroda, K. C. Miller, M.
Wilde-Piorko, K. Komminaho, J. Jacyna, and L. Korabliova,
Crustal structure of the Trans-European suture zone region
along POLONAISEʼ97 seismic profile P4: Journal of Geophysical
Research, 108, doi:10.1029/2003JB002426, 2003.
Figure 3. Two-dimensional P-wave velocity model for CELEBRATION 2000 profile
CEL05 obtained by forward ray tracing. The thick solid lines are layer boundaries and
thin lines are isovelocity contours in km/s; numbered triangles refer to shot points.
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