HR: 1340h
AN: T53B-0506 [Abstracts]
TI: Active Foreland Deformation of the Southeastern Carpathians from Deep Seismic Reflection Profiles
DRACULA II and III: Genetic Relationships with the Vrancea Seismogenic Region
AU: * Knapp, C C
EM: camelia@geol.sc.edu
AF: Department of Geological Sciences, University of South Carolina, 701 Sumter Street, Columbia, SC 29208
United States
AU: Knapp, J H
EM: knapp@geol.sc.edu
AF: Department of Geological Sciences, University of South Carolina, 701 Sumter Street, Columbia, SC 29208
United States
AU: Mocanu, V
EM: mocanu@gg.unibuc.ro
AF: University of Bucharest, 36-46 Mihail Kogalniceanu Street, Bucharest, 70709
Romania
AU: Munteanu, L
EM: laur@infp.ro
AF: National Institute for Earth Physics, PO Box MG-2, Bucharest, Magurele, SC 4930117
Romania
AU: Trenkamp, R
EM: trenkamp@geol.sc.edu
AF: Department of Geological Sciences, University of South Carolina, 701 Sumter Street, Columbia, SC 29208
United States
AU: Raileanu, V
EM: raivic@infp.ro
AF: National Institute for Earth Physics, PO Box MG-2, Bucharest, Magurele, SC 4930117
Romania
AU: Mucuta, D
EM: dmucuta@geol.sc.edu
AF: Department of Geological Sciences, University of South Carolina, 701 Sumter Street, Columbia, SC 29208
United States
AU: Fillerup, M
EM: mfillerup@geo.sc.edu
AF: Department of Geological Sciences, University of South Carolina, 701 Sumter Street, Columbia, SC 29208
United States
AU: Fort, M
EM: mdfort@passcal.nmt.edu
AF: IRIS/PASSCAL, 100 EAST ROAD, SOCORRO, NM 87801
United States
AU: Harder, S
EM: harder@geo.utep.edu
AF: Department of Geological Sciences, University of Texas at El Paso, J.W. Miller Geophysical Laboratory,
El Paso, TX 79968
United States
AB:
Project DRACULA (Deep Reflection Acquisition Constraining Unusual Lithospheric Activity), a collaboration between the
University of South Carolina, the University of Bucharest, and the National Institute for Earth Physics in Romania, involved
the acquisition of 320 km of deep (60 s) multichannel seismic reflection data in the summer of 2004. Project DRACULA involved
the acquisition of three transects (DRACULA I, II, and III) surrounding the Vrancea zone of Romania in order to evaluate the
existing competing models for the origin, lithospheric structure, and geodynamic setting of this highly disputable
intermediate-depth (70-200 km) seismogenic region. While the DRACULA I profile, acquired in the hinterland of the
southeastern Carpathians, is presented elsewhere, here we discuss preliminary results from lines DRACULA II and III collected
in the foreland, east and south of the seismogenic area. DRACULA II and III profiles were designated to image the crustal
structure of the foreland across the Pecineaga-Camena, and respectively, Intramoesian Faults, two of the active foreland
faults, in order to place constraints on the duration, timing, and scale of foreland deformation that appears to be a direct
response to the Vrancea seismogenic body. The DRACULA II line shows strong subhorizontal reflections from 14.5-15.0 (approx.
45-48 km) in the eastern side of the Pecineaga-Camena fault that we interpret to be the Moho. Unusually layered reflectivity
is seen down to 20 s in this part of the line. A very intriguing high-amplitude subhorizontal reflector, approximately 7 km
long, is observed at 35.5 s (approx. 130 km). The western side of the line, across the fault, displays a fairly transparent
lower crust and uppermost mantle, possibly indicating the depth penetration of the Pecineaga-Camena fault across the Moho.
The DRACULA III line displays a very high amplitude reflection at 14.0 s (aprox. 42 km) in the south-west that dips slightly
to 14.5-15.s (45-48 km) in the north-east. This reflection is interpreted to be the Moho, but it is premature to comment
whether this variation in its depth is related to the penetration of the Intramoesian fault into the lithospheric mantle.
Although preliminary, results from the DRACULA II and III profiles indicate that the active crustal faults in the foreland
that have significant surface expressions (up to 100 m escarpments) continue in the uppermost mantle, and may be related to
the Vrancea seismogenic zone.
DE: 9800 GENERAL OR MISCELLANEOUS
SC: Tectonophysics [T]
MN: 2004 AGU Fall Meeting