Download Seismic view on the svalbard passive continental margin

Acta Geophysica
vol. 61, no. 5, Oct. 2013, pp. 1088-1100
DOI: 10.2478/s11600-013-0126-0
Seismic View
on the Svalbard Passive Continental Margin
Wojciech CZUBA
Institute of Geophysics, Polish Academy of Sciences, Warszawa, Poland
e-mail: [email protected]
Abstract
Deep seismic sounding measurements were performed in the
continent-ocean transition zone of the western Svalbard and Barents Sea
margin, during the expeditions in 1985-2008. Seismic energy (airgun and
TNT shots) was recorded along several profiles by onshore seismic
stations and ocean bottom seismometers, and hydrophone systems. Good
quality reflected and refracted P waves provided an excellent data base
for a seismic modelling along the profiles. TNT sources were recorded
even up to 300 km distances. A minimal depth of about 6 km of the
Moho interface was found east of the Molloy Deep. The Moho
discontinuity dips down to 28 km beneath the continental part of the
northernmost profile and down to maximum 32 km beneath other
profiles. The evolution of the region is considered to be within a shearrift tectonic setting. The continent-ocean transition zone along the
northernmost profile is mostly dominated by extension; therefore, the last
stage of the development of the margin can be classified as rifting. The
uplifted Moho interface close to the Molloy Deep can be interpreted as
a south-western end of the Molloy Ridge. The margin of the southern
Spitsbergen is rather of sheared character while the western Barents Sea
margin is of slow to ultraslow spreading type.
Key words: continent-ocean transition, seismic crustal structure,
Svalbard, North Atlantic, Knipovich Ridge.
________________________________________________
© 2013 Institute of Geophysics, Polish Academy of Sciences
Unauthenticated
Download Date | 6/17/17 10:03 PM
SEISMIC VIEW ON THE SVALBARD PASSIVE CONTINENTAL MARGIN
1.
1089
INTRODUCTION
Svalbard Archipelago is located at the north-western corner of the Barents
Sea continental platform bordered to the west by passive continental margin
(Fig. 1, insert map). Spitsbergen is the main island of the archipelago. This
region is an interesting and important area for understanding the evolution of
the North Atlantic and Arctic Oceans. This is the youngest region of the
Fig. 1. Location map of the seismic profiles in the ocean-continent transition zone in
the western Svalbard and Barents Sea margin on the background of topography/
bathymetry map (Jakobsson et al. 2000) and simplified tectonic elements
(Gabrielsen et al. 1990, Faleide et al. 2008). Stars (yellow for profiles K1 and C1)
and triangles are receivers, thin lines and red dots are airgun and chemical (TNT)
shots, respectively. HFZ – Hovgård Fracture Zone, MFZ – Molloy Fault Zone,
MR – Molloy Ridge, SFZ – Spitsbergen Fault Zone. Colour version of this figure is
available in electronic edition only.
Unauthenticated
Download Date | 6/17/17 10:03 PM
1090
W. CZUBA
Atlantic and Arctic Oceans giving a good source to study processes leading
to their opening. Rifting and subsequent sea-floor spreading processes in the
North Atlantic Ocean and the development of the passive sheared
continental margin of the Barents Sea continental platform, these are the
processes which form the today’s face of the Earth. The development of this
margin is strongly connected with the history of opening of the North
Atlantic Ocean (Jackson et al. 1990, Lyberis and Manby 1993a, b, Ohta
1994). The Svalbard passive continental margin has been investigated by
geophysical research over the last 30 years
This paper concerns deep seismic sounding studies (DSS) performed in
the continent-ocean transition zone of the western Svalbard and Barents Sea
margin during the international expeditions in 1985-2008.
Seismic energy (TNT explosions and airgun) was recorded along several
transects by onshore (land) seismic stations and ocean bottom seismographs
(OBS), and hydrophone systems (OBH). Good seismic records from airgun
shots were obtained up to 200 km distances at onshore stations and 50 km at
OBSs. TNT shooting was recorded even up to 300 km distances.
2.
TECTONIC SETTING
The geological history of Svalbard Archipelago is ranging in age from
Precambrian to Cenozoic (e.g., Birkenmajer 1993, Ohta 1994, Harland 1997,
Dallmann 1999). Its structure reflects the relative activity of the Eurasian
and the North American plates (Eldholm et al. 1987) and shows a multiorogenic development with several prominent tectonic stages (e.g., Dallmann
1999, Harland 1997). The tectonic history of the region can be simplified
into terms of three main geological stages (Sellevoll et al. 1991).
The first important tectonic event is related to the Caledonian Orogeny
(Birkenmajer 1981). Its effects are particularly well visible in the Eastern
Svalbard (Sellevoll et al. 1991).
The next main tectonic stage is called the Late Devonian Svalbardian
event. During this event, the eastern Spitsbergen and Nordaustlandet have
moved northward from eastern Greenland to a position north of Greenland
(Sellevoll et al. 1991). This is a disputable hypothesis (Harland 1997). Thus,
the eastern part of Svalbard has attached to western Spitsbergen. Western
Spitsbergen was supposed to be located there before these movements or it
has slightly moved northward from a shorter distance (Harland et al. 1974,
Sellevoll et al. 1991).
Cenozoic tectonic processes in the Svalbard area were related to the
structural history of the western Barents Sea margin. The relative motion
between Svalbard and Greenland took place along the Hornsund Fault Zone,
traced from just south of Bjørnøya at ca. 75ºN to about 79ºN (Sundvor and
Eldholm 1979, Eldholm et al. 1980). This regional fault zone has acted as an
Unauthenticated
Download Date | 6/17/17 10:03 PM
SEISMIC VIEW ON THE SVALBARD PASSIVE CONTINENTAL MARGIN
1091
incipient plate boundary between the opening Arctic Ocean and the Barents
Sea shelf.
The Barents Sea region has been affected by several stages of tectonism
from the time of the Caledonian Orogeny (Birkenmajer 1981, Talwani and
Eldholm 1977). The western sector of the Barents Sea has been tectonically
most active during the Mesozoic and Cenozoic times (Gabrielsen et al.
1990). There has occurred magmatic activity during the Palaeocene and
Eocene in the western part of the Barents Sea, probably related to the breakup of the North Atlantic Ocean. It has started with regional dextral shear in
the Early Palaeocene and continued with rifting from about 36 Ma ago
(Talwani and Eldholm 1977, Myhre et al. 1982, Eldholm et al. 1987).
The evolution of the North Atlantic Ocean can be divided into two main
phases. The continental break-up occurred and sea floor spreading started
along the Reykjanes, Aegir, and Mohns Ridges (Talwani and Eldholm 1977)
during the first phase in the Early Eocene. The shearing along faults between
northeast Greenland and Svalbard has created the Spitsbergen fold and thrust
belt to the north. The result of this process was the Western Spitsbergen
Orogeny (Harland et al. 1974, Steel et al. 1985). Rapid erosion has increased
sedimentary load along the Svalbard western margin and turned the epicontinental, littoral basin of central Spitsbergen into a rapidly subsiding foreland
basin (Eiken and Austegard 1987). Conversely, dense mantle material was
intruded most significantly at the Vestbakken Volcanic Province after thinning and weakening of the crust caused by transtension (Eiken and Austegard
1987, Eldholm et al. 1987, Sundvor and Eldholm 1979).
The second phase of North Atlantic evolution was marked by a change in
the spreading direction from NNW-SSE to NW-SE. It has resulted the
termination of the Western Spitsbergen Orogeny. This has begun in Early
Oligocene when spreading in the Labrador sea stopped (Mosar et al. 2002,
Talwani and Eldholm 1977). The beginning of the phase has unlocked the
northward development of the Mid Atlantic Ridge. The spreading axis has
developed into the Spitsbergen Shear Zone creating the asymmetric, ultraslow and obliquely-spreading Knipovich Ridge. Around 23 Ma ago spreading started further, along the Molloy Ridge, and around 10 Ma ago
continental break-up occurred along the Fram Strait. This has established
connection between the Arctic and the Northern Atlantic ridges (Lundin and
Doré 2002, Crane et al. 1991).
3.
CONTINENT-OCEAN TRANSITION
Good quality records of refracted and reflected P waves were obtained along
the entire profiles lengths (Fig. 1). They were an excellent data base for following seismic modelling (Fig. 2) along the profiles. Details about experiUnauthenticated
Download Date | 6/17/17 10:03 PM
1092
W. CZUBA
Fig. 2. 2D seismic P-wave velocity models developed by ray-tracing technique
along profiles shown on Fig. 1, from north (top) to south (bottom), respectively.
Black lines represent seismic discontinuities (boundaries), colours represent the
distribution of the P-wave velocity and numbers in the model are P-wave velocities
in km/s. Gray-shaded belt marks ocean-continent transition zones in every model.
All the models are in the same geometric and colour scale. C1 – marks the crossing
place of the K1 profile with the C1 profile. Colour version of this figure is available
in electronic edition only.
Unauthenticated
Download Date | 6/17/17 10:03 PM
SEISMIC VIEW ON THE SVALBARD PASSIVE CONTINENTAL MARGIN
1093
ments, data processing and quality, as well as modelling procedures and
interpretations are described in Czuba et al. (1999, 2005, 2008, 2011), Libak
et al. (2012), Ljones et al. (2004), and Ritzmann et al. (2004). Although all
the profiles are WARR profiles, their setup was different because of polar
region logistics, instruments availability, and geometry. Seismic sources
were used in the sea only for all the profiles. Profiles K1 and C1 were
performed using TNT sources and seismic land stations (5 channels, vertical
component) only. Profiles 99200, 99400, Horsted ’05, and BIS-2008 were
performed using seismic land stations, OBSs and OBHs (99200 and 99400
only) as receivers, and dense system of airgun shots as well as TNT shots to
extend distance of recording. The profile 99200 geometry setup was partly
off-line but seismic modelling was performed like for full in-line setup using
real distances between sources and receivers. The Profile 8 was full marine
profile with airgun shots and OBSs only. The profile BIN-2008 was
performed using seismic land stations, OBSs and airgun shots. All data were
processed in the same way, transformed at the end to SEG-Y files with
100 Hz sampling. Different filters were used dynamically during picking of
arrivals of seismic energy. Seismic models were calculated using P waves by
ray-tracing trial-and-error method using wide available software.
A minimal depth of about 6 km of the Moho discontinuity was determined east of the Molloy Deep. Here, the upper mantle exhibits P-wave
velocity of about 7.9 km/s, and the crustal thickness does not exceed 4 km It
is associated with the Molloy Transform Fault Zone or with the Molloy
Ridge connecting the Molloy Transform Fault Zone with the Spitsbergen
Transform Fault Zone.
The Moho discontinuity dips down to 28 km beneath the continental part
of the 99200 (northernmost profile) and K1 profiles, and down to maximum
32 km beneath the other profiles. The high P-wave velocity below the Moho
interface increases generally up to 8.2 km/s, reaching maximal 8.6 km/s
beneath the continental part of the profile located in the central part of the
west coast of Spitsbergen (K1). The high P-wave velocity 8.6 km/s could
seem to be anomalous but it is modelled with accuracy in the range of 0.10.2 km/s. It could be connected somehow with the close location of young
active rifting processes (Knipovich Ridge). This is the closest location to the
continental crust along profiles described here.
The continental crust consists of two or three crystalline layers. The
lowermost crustal continental layer with the P-wave velocity in the order of
7 km/s does not exist in the continental crust along three of the profiles
described in this paper. It is completely missing (BIN-2008) or it exists in
the transition zone only (99200, Horsted ’05). These layers or even high
velocity bodies are connected with serpentinizing or partial melting in the
magma-reach region. A layer characterised by P-wave velocities signifiUnauthenticated
Download Date | 6/17/17 10:03 PM
1094
W. CZUBA
cantly above 7 km/s is found along the continental part of the BIS-2008
profile but it is very thin and it is hard to define as a normal continental
lower crust. Profiles 99400 and K1 show clear continental lower crustal
layer characterised by P-wave velocities of 6.7-7.0 km/s and 7.1-7.2 km/s,
respectively.
The oceanic crust is generally similar in terms of thickness along all the
profiles studied here but it is composed of more layers in those three
southern profiles, where the opening of Northern Atlantic happened earlier.
Differences in crustal thickness are the result of different spreading rate in
the tectonic history. The thickness is minimal in the vicinity of mid-oceanic
ridge. There, the P-wave upper mantle velocities are lowest along these
profiles, being even lower than 7.9 km/s (Profile 8, BIN-2008). The sedimentary part of the continent-ocean transition zone is characterised by
a complex basin structure, known in the Spitsbergen region as west Spitsbergen foreland basin (Eiken and Austegard 1987). The P-wave velocity at
the topmost layers is very low, being even 1.8-1.9 km/s (BIS-2008, 99200),
which indicates high water saturation of the rock body.
Margins crossing by several of the profiles studied here have a character
of sheared margin with rather short continent-ocean transition and abrupt
change of the crustal thickness there (99400, K1, Horsted ’05). The shearing
took place mostly along the Hornsund Fault Zone (Faleide et al. 1991,
2008). Margins crossing by the other profiles have more complex history
and their transition zone structure indicates the transform character in the
past, but in the present they can be classified rather as rifted margins with
ultra-slow spreading.
4.
MARGIN ANISOTROPY
Seismic modelling described in Czuba et al. (1999) for profiles K1 and C1
was conducted to coincide parameters at the crossing area. An isotropic
medium was assumed. Remodelling of the C1 profile was done for the
purpose of this study to fit better the recorded seismic data. In this case,
assuming anisotropic medium, seismic velocities at the crossing area can be
different along both profiles. The same ray-tracing trial-and-error technique
was used during both modelling cases. The remodelling has resulted in
changing of the seismic model. The new model is shown in Fig. 3. The
difference is obtained in the lower crustal layer, where P-wave velocities in
the corrected model are 0.15 km/s in an average higher, than those along K1
profile in the same place. Moreover, the Moho depth agrees better in both
models. According to accuracy discussion in several papers with the same
seismic modelling method used (Janik et al. 2002, Grad et al. 2003, 2006,
2008, Środa et al. 2006), this velocity difference is significant. Such a difUnauthenticated
Download Date | 6/17/17 10:03 PM
SEISMIC VIEW ON THE SVALBARD PASSIVE CONTINENTAL MARGIN
1095
SYNTHETIC SECTION
10
RED. TIME T-X/8 (s)
8
6
4
2
0
150
200
250
300
350
400
SECTION & TRAVELTIMES
10
RED. TIME T-X/8 (s)
8
6
PmP
Pn
4
Pg
2
0
150
200
250
N
300
350
400
S
K1
0
0
4.80
6.25
Depth [km]
10
10
6.40
7.30
20
Moh
20
o
7.40
Moho
30
40
8.63
30
Profile C1
150
200
Vertical exaggeration x3
250
300
350
Vp [km/s]
8.0
7.5
7.0
6.5
6.0
5.5
5.0
4.5
4.0
3.5
3.0
2.5
2.0
40
400
Distance [km]
Fig. 3. Corrected 2D seismic modelling along C1 profile: P-wave velocity model
developed by ray-tracing technique (bottom), observed record section with calculated travel times (middle), and synthetic seismograms (top). K1 marks the crossing
place of the C1 profile with the K1 profile. Main P-wave phases: Pg – crustal
refraction, Pn – Moho refraction, PmP – Moho reflection. Other descriptions as in
Fig. 2. Colour version of this figure is available in electronic edition only.
Unauthenticated
Download Date | 6/17/17 10:03 PM
1096
W. CZUBA
ference is probably caused by seismic anisotropy. It is rather small anisotropy, in the order of 2%.
At pressures of 200 to 300 MPa, corresponding to about 10-15 km depth,
much of the anisotropy disappears, primarily due to the closure of cracks.
Therefore, any crustal anisotropy below these depths is probably caused by
other phenomena (Meissner et al. 2006, Środa 2006). Thus, the anisotropy in
this case is rather not connected with cracks and faults existing closer to the
surface. The C1 profile runs along the Spitsbergen coast and it is approximately parallel to main geological structures, while the K1 profile crosses
these structures (e.g., Knipovich Ridge and Hornsund Fault Zone in Fig. 1)
and the C1 profile almost perpendicularly. Thus, the anisotropy could be
connected with stresses caused by extensional regime acting in the lower
crust during spreading processes in the relatively young Knipovich Ridge.
5.
CONCLUSIONS
Thanks to the dense system of airgun shots it was possible to model very
accurately the seismic crustal structure along profiles located in the western
Svalbard and Barents Sea continental passive margin. There were found
sedimentary basins (probably of Cenozoic sequence) with a low seismic
velocity and the thinned continental crust in the continent-ocean transition
zone.
The evolution of this region appears to be within a shear-rift tectonic
setting. The continent-ocean transition zone along the northernmost profile
(99200) is mostly dominated by extension; therefore, the last stage of the
development of the margin is classified as rifting. It can be interpreted as the
result of an extensional regime, acting here from the anomaly 13 time (Eiken
and Austegard 1987, Faleide et al. 1991, Harland 1997), which probably has
hidden previous shear structure of the margin crossed by the 99200 profile
(Czuba et al. 2005). The margins along southern Spitsbergen profiles are
rather of sheared character, while the profiles crossing western Barents Sea
margin are of slow to ultraslow spreading type. It could be explained by the
tectonic history of the region. The most advanced spreading processes occur
in the southern part of the study region, where the opening of the North
Atlantic has started. Then new spreading processes have appeared in the
north (Molloy Deep, Molloy Ridge) and the central part of the region
(profiles 99400, K1, Horsted ’05) has been keeping the transform regime for
longer time. P-wave anisotropy was determined in the lower crust in the
central part of the region. This is the first anisotropy investigation using DSS
P-wave modelling in the region known to the author.
A c k n o w l e d g m e n t s . The public domain GMT software (Wessel and
Smith 1991, 1998) was used to produce the map with profiles (Fig. 1).
Unauthenticated
Download Date | 6/17/17 10:03 PM
SEISMIC VIEW ON THE SVALBARD PASSIVE CONTINENTAL MARGIN
1097
References
Birkenmajer, K. (1981), The geology of Svalbard, the western part of the Barents
Sea, and the continental margin of Scandinavia. In: A.E.M. Nairn,
M. Churkin Jr., and F.G. Stehli (eds.), The Ocean Basins and Margins, The
Arctic Ocean, Vol. 5, Plenum Press, New York, 265-329.
Birkenmajer, K. (1993), Tertiary and cretaceous faulting in a proterozoic metamorphic terrain, SE Wedel Jarlsberg Land, Spitsbergen, Bull. Pol. Acad. Sci.
Earth Sci. 41, 3, 181-189.
Crane, K., E. Sundvor, R. Buck, and F. Martinez (1991), Rifting in the northern Norwegian-Greenland Sea: Thermal tests of asymmetric spreading, J. Geophys.
Res. 96, B9, 14529-14550, DOI: 10.1029/91JB01231.
Czuba, W., M. Grad, and A. Guterch (1999), Crustal structure of north-western
Spitsbergen from DSS measurements, Pol. Polar Res. 20, 2, 131-148.
Czuba, W., O. Ritzmann, Y. Nishimura, M. Grad, R. Mjelde, A. Guterch, and
W. Jokat (2005), Crustal structure of northern Spitsbergen along the deep
seismic transect between the Molloy Deep and Nordaustlandet, Geophys. J.
Int. 161, 2, 347-364, DOI: 10.1111/j.1365-246X.2005.02593.x.
Czuba, W., M. Grad, A. Guterch, M. Majdański, M. Malinowski, R. Mjelde,
M. Moskalik, P. Środa, M. Wilde-Piórko, and Y. Nishimura (2008), Seismic crustal structure along the deep transect Horsted’05, Svalbard, Pol.
Polar Res. 29, 3, 279-290.
Czuba, W., M. Grad, R. Mjelde, A. Guterch, A. Libak, F. Krüger, Y. Murai,
J. Schweitzer, and the IPY Project Group (2011), Continent-oceantransition across a trans-tensional margin segment: off Bear Island, Barents
Sea, Geophys. J. Int. 184, 2, 541-554, DOI: 10.1111/j.1365-246X.2010.
04873.x.
Dallmann, W.K. (1999), Lithostratigraphic lexicon of Svalbard: Review and recommendations for nomenclature use. Upper Palaeozoic to Quarternary
Bedrock, Committee on the Stratigraphy of Svalbard, Norsk Polarinstitutt,
Tromsø, Norway.
Eiken, O., and A. Austegard (1987) The Tertiary orogenic belt of West Spitsbergen:
Seismic expressions of the offshore sedimentary basins, Norsk. Geol.
Tidsskr. 67, 4, 383-394.
Eldholm, O., E. Sundvor, and G. Wissmann (1980), The continental margins of the
Norwegian–Greenland Sea: Recent and outstanding problems, Phil. Trans.
Roy. Soc. A 294, 1409, 77-86, DOI: 10.1098/rtsa.1980.0014.
Eldholm, O., J.I. Faleide, and A.M. Myhre (1987), Continental-ocean transition at
the western Barents Sea/Svalbard continental margin, Geology 15, 12,
1118-1122, DOI: 10.1130/0091-7613(1987)15<1118:CTATWB>2.0. CO;2.
Faleide, J.I., S.T. Gudlaugsson, O. Eldholm, A.M. Myhre, and H.R. Jackson (1991),
Deep seismic transects across the sheared western Barents Sea – Svalbard
Unauthenticated
Download Date | 6/17/17 10:03 PM
1098
W. CZUBA
continental margin, Tectonophysics 189, 1-4, 73-89, DOI: 10.1016/00401951(91)90488-E.
Faleide, J.I., F. Tsikalas, A.J. Breivik, R. Mjelde, O. Ritzmann, Ø. Engen, J. Wilson,
and O. Eldholm (2008), Structure and evolution of the continental margin
off Norway and the Barents Sea, Episodes 31, 1, 82-91.
Gabrielsen, R.H., R.B. Færseth, L.N. Jensen, J.E. Kalheim, and F. Riis (1990)
Structural elements of the Norwegian continental shelf, Part I: The Barents
Sea Region, Norwegian Petroleum Directorate, Bull. No. 6, 1-33.
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. Gaczyński,
P. Środa, K.C. Miller, M. Wilde-Piórko, K. Komminaho, J. Jacyna, and
L. Korabliova (2003), Crustal structure of the Trans-European suture zone
region along POLONAISE’97 seismic profile P4, J. Geophys. Res. 108,
B11, 2541, DOI: 10.1029/2003JB002426.
Grad, M., A. Guterch, G.R. Keller, T. Janik, E. Hegedűs, J. Vozár, A. Ślączka,
T. Tiira, and J. Yliniemi (2006), Lithospheric structure beneath transCarpathian transect from Precambrian platform to Pannonian basin:
CELEBRATION 2000 seismic profile CEL05, J. Geophys. Res. 111, B3,
B03301, 1-23, DOI: 10.1029/2005JB003647.
Grad, M., A. Guterch, Z. Mazur, G.R. Keller, A. Špičák, P. Hrubcová, and
W.H. Geissler (2008), Lithospheric structure of the Bohemian Massif and
adjacent Variscan belt in central Europe based on profile S01 from the
SUDETES 2003 experiment, J. Geophys. Res. 113, B10304, DOI: 10.1029/
2007JB005497.
Harland, W.B. (1997), The geology of Svalbard, Geological Society memoir No. 17,
The Geological Society, London.
Harland, W.B., J.L. Cutbill, P.F. Friend, D.J. Gobbett, D.W. Holliday, P.I. Maton,
J.R. Parker, and R.H. Wallis (1974), The Billefjorden fault zone, Spitsbergen: The long history of a major tectonic lineament, Norsk Polarinstitutt,
Oslo, No. 161.
Jackson, H.R., J.I. Faleide, and O. Eldholm (1990), Crustal structure of the sheared
southwestern Barents Sea continental margin, Mar. Geol. 93, 119-146,
DOI: 10.1016/0025-3227(90)90080-4.
Jakobsson, M., N. Cherkis, J. Woodward, R. Macnab, and B. Coakley (2000), New
grid of Arctic bathymetry aids scientists and mapmakers, Eos Trans. AGU
81, 9, 89-96, DOI: 10.1029/00EO00059.
Janik, T., J. Yliniemi, M. Grad, H. Thybo, T. Tiira, and POLONAISE P2 Working
Group 1 (2002), Crustal structure across the TESZ along POLONAISE‘97
seismic profile P2 in NW Poland, Tectonophysics 360, 1-4, 129-152, DOI:
10.1016/S0040-1951(02)00353-0.
Libak, A., C.H. Eide, R. Mjelde, H. Keers, and E.R. Flüh (2012), From pull-apart
basins to ultraslow spreading: Results from the western Barents Sea
Margin, Tectonophysics 514-517, 44-61, DOI: 10.1016/j.tecto.2011.09.020.
Unauthenticated
Download Date | 6/17/17 10:03 PM
SEISMIC VIEW ON THE SVALBARD PASSIVE CONTINENTAL MARGIN
1099
Ljones, F., A. Kuwano, R. Mjelde, A. Breivik, H. Shimamura, Y. Murai, and
Y. Nishimura (2004), Crustal transect from the North Atlantic Knipovich
Ridge to the Svalbard Margin west of Hornsund, Tectonophysics 378, 1-2,
17-41, DOI: 10.1016/j.tecto.2003.10.003.
Lundin, E., and A.G. Doré (2002), Mid-Cenozoic post-breakup deformation in the
“passive” margins bordering the Norwegian–Greenland Sea, Mar. Petrol.
Geol. 19, 1, 79-93, DOI: 10.1016/S0264-8172(01)00046-0.
Lyberis, N., and G. Manby (1993a), The origin of the West Spitsbergen Fold Belt
from geological constraints and plate kinematics: Implications for the
Arctic, Tectonophysics 224, 4, 371-391, DOI: 10.1016/0040-1951(93)
90039-M.
Lyberis, N., and G. Manby (1993b), The West Spitsbergen Fold Belt: The result of
Late Cretaceous-Palaeocene Greenland-Svalbard convergence?, Geol. J.
28, 2, 125-136, DOI: 10.1002/gj.3350280203.
Meissner, R., W. Rabbel, and H. Kern (2006), Seismic lamination and anisotropy of
the Lower Continental Crust, Tectonophysics 416, 1-4, 81-99, DOI:
10.1016/j.tecto.2005.11.013.
Mosar, J., E.A. Eide, P.T. Osmundsen, A. Sommarunga, and T.H. Torsvik (2002),
Greenland–Norway separation: a geodynamic model for the North Atlantic,
Norw. J. Geol. 82, 4, 281-298.
Myhre, A.M., O. Eldholm, and E. Sundvor (1982), The margin between Senja and
Spitsbergen fracture zones: Implications from plate tectonics,
Tectonophysics 89, 1-3, 33-50, DOI: 10.1016/0040-1951(82)90033-6.
Ohta, Y. (1994), Caledonian and Precambrian history in Svalbard: a review, and an
implication of escape tectonics, Tectonophysics 231, 1-3, 183-194, DOI:
10.1016/0040-1951(94)90129-5.
Ritzmann, O., W. Jokat, W. Czuba, A. Guterch, R. Mjelde, and Y. Nishimura
(2004), A deep seismic transect in northwestern Svalbard at Kongsfjorden
(Ny Alesund) and the implications for the Cenozoic break-up from
Greenland: A sheared margin study, Geophys. J. Int. 157, 2, 683-702, DOI:
10.1111/j.1365-246X.2004.02204.x.
Sellevoll, M.A., S.J. Duda, A. Guterch, J. Pajchel, E. Perchuć, and F. Thyssen
(1991), Crustal structure in the Svalbard region from seismic measurements, Tectonophysics 189, 1-4, 55-71, DOI: 10.1016/0040-1951(91)
90487-D.
Steel, R., J. Gjelberg, W. Helland-Hansen, K. Kleinspehn, A. Nøttvedt, and M. RyeLarsen (1985), The Tertiary strike-slip basins and orogene belt of
Spitsbergen. In: K. Biddle and N. Cristie-Blick (eds.), Strike-slip
Deformation, Basin Formation, and Sedimentation, Soc. Econ. Paleontol.
Mineral., Spec. Publ. 37, 339-359.
Sundvor, E., and O. Eldholm (1979), The western and northern margin off Svalbard,
Tectonophysics 59, 1-4, 239-250, DOI: 10.1016/0040-1951(79)90048-9.
Unauthenticated
Download Date | 6/17/17 10:03 PM
1100
W. CZUBA
Środa, P. (2006), Seismic anisotropy of the upper crust in southeastern Poland –
effect of the compressional deformation at the EEC margin: Results of
CELEBRATION 2000 seismic data inversion, Geophys. Res. Lett. 33, 22,
L22302, DOI: 10.1029/2006GL027701.
Środa, P., W. Czuba, M. Grad, A. Guterch, A.K. Tokarski, T. Janik, M. Rauch,
G.R. Keller, E. Hegedűs, J. Vozár, and CELEBRATION 2000 Working
Group (2006), Crustal and upper mantle structure of the Western
Carpathians form CELEBRATION 2000 profiles CEL01 and CEL04:
seismic models and geological implications, Geophys. J. Int. 167, 2, 737760, DOI: 10.1111/j.1365-246X.2006.03104.x.
Talwani, M., and O. Eldholm (1977), Evolution of the Norwegian–Greenland Sea,
Geol. Soc. Am. Bull. 88, 7, 969-999, DOI: 10.1130/0016-7606(1977)88
<969:EOTNS>2.0.CO;2.
Wessel, P., and W.H.F. Smith (1991), Free software helps map and display data, Eos
Trans. AGU 72, 41, 441-446, DOI: 10.1029/90EO00319.
Wessel, P., and W.H.F. Smith (1998), New, improved version of Generic Mapping
Tools released, Eos Trans. AGU 79, 47, 579, DOI: 10.1029/98EO00426.
Received 20 December 2012
Received in revised form 7 March 2013
Accepted 19 March 2013
Unauthenticated
Download Date | 6/17/17 10:03 PM