Marine seismic survey area: Off Europe / Greenland - Reflection seismic data
Refraction seismic data
(1) Norwegian-Greenland Sea (NGS) | (2) Baltic Sea | (3) OFF Portugal | (4) Mediterranean Sea |
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BGR88 ARK V/3 1988 | |||
BGR74 (Longva) 1974 | PQ2 (Polar Queen) 1996 | SO75 (Sonne) 1991 | MSM14/2 GeoNORM (MS Merian) 2010 |
BGR75 (Longva) 1975 | MSM52 (MSM Merian) 2016 | ||
BGR76 (Explora) 1976 | |||
NGT83 (Prospekta/Conrad) 1983 |
Source: BGR
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Cruise BGR74 1974
Cruise BGR75 1975
Vessel Longva
North Atlantic
Summary
Reconnaissance surveys were carried out in 1974 and 1975 within the framework of the BGR program "Geoscientific studies in the North Atlantic". The areas covered were the continental margin of Spitsbergen, the Barents Sea (Hinz & Schlüter, 1980) and the Norwegion continental margin.
Three main depositional sequences have been determined in the seismic records taken off West Spitsbergen:
- a Plio-Pleistocene sequence SPI-I with velocities of 1.7 to 2.8 km/s;
- a Pliocene allochthonous sequence SPI-II with velocities of 2.4 to 2.8 km/s underlying unconformity U1;
a pre-Middle Oligocene sequence SPI-III with velocities of 2.9 to 4.8 km/s underlying a distinct unconformity (U2) and deposited in front of the downfaulted Spitsbergen Platform indicating some opening of the Greenland Sea already before the time of magmatic anomaly 13 (36 m.y. B.P.).
A marked change in the seismic configuration of the oceanic basement has been observed about 30 to 40 km east of the central Knipovich graben. The transition from the oceanic crust of the Knipovich Ridge to the strongly faulted, continental substratum of the Spitsbergen Platform occurs over a narrow zone and is associated with a pre-Middle Oligocene depocenter.
Total length of lines | |
Sampling rate | 4 ms |
Record length | 10 000 ms |
Streamer | digital - 24 channels |
Total length of lines | |
Sampling rate | 4 ms |
Record length | 10 000 ms |
Streamer | digital - 48 channels |
References:
Hinz, K., Schlüter, H.U., 1980, Continental margin off East Greenland. Proceedings of the 10th World Petroleum Congress, September 1979, Bucharest, Heyden, London, Vol. 2, pp.405-418.
Hinz, K., Eldholm, O., Block, M., Skogseid, J., 1993, Evolution of the North Atlantic volcanic margins. In J.R. Parker (ed.): Petroleum Geology of Northwest Europe, Proc. of the 4th Conference, Geol. Soc. Pub., London, pp.901-913.
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Cruise BGR76 1976
Vessel Explora
Barentsea
Total length of lines | |
Sampling rate | 4 ms |
Record length | 6 000 ms |
Streamer | digital - 48 channels |
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Cruise NGT83 1983
Vessel Prospekta / Conrad
Norwegian Sea
Total length of lines | |
Sampling rate | 4 ms |
Record length | 12000 ms |
Streamer | digital - 48 channels |
Summary
Conventional reflection seismic gives us a good image of the upper part of the crust. An investigation of the deeper parts of the crust was possible in 1991 by simulation a long streamer using two ships (LDGO & BGR). With this experience the BGR resolved a survey in the Norwegian-Greenland Sea from 15.08. to 27.09.1983. The main topics were:
- an image of the deep crust of the conjugated continental margins of the Norwegian-Greenland Sea.
- localization of the ocean-continent boundary.
- a record of the deepest sediments in the basins and structures within the basement.
The survey showed that two-ship experiments are possible without any technical problems. There were no technical failures and no interruptions of the measurements.
During the survey with a total length of 4156 km 23 lines were resolved as expanded spread profiles (ESP)(1708 km) and 13 lines were resolved as wide angle profiles (WA)(1415 km) by the vessels S/V PROSPEKTA and R/V D. CONRAD.
In the area between the ESP and the WA lines conventional reflection seismic profiles (CDP) were resolved. In addition 96 sonobuoys were deployed along the WA and the CDP profiles.
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Cruise ARKV/3 1988
Vessel Polarstern
East Greenland
Summary
In July/August 1988 a seismic reconnaisance survey was carried out with F.S. Polarstern on the perennially ice covered East Greenland shelf between latitudes 73°N and 81°N.
Although very dense sea ice and fog hampered the seismic programme, 14 reflection seismic lines with a total length of 2.016 km and 12 sonobuoy refraction profiles were recorded.
The following results were obtained:
- On the wide Holm Land shelf province north of 79°N three possible Cretaceous rift basins were observed.
- A buildup of layered extrusive basaltic rocks forming a wedge of seaward dipping reflectors underlies the Holm Land continental slope.
- On the Northeastern Greenland shelf province the existence of a wide sedimentary basin was demonstrated north of 76°N.
- South of 76°N four volcanic structures from the continent to ocean were observed: The zone of Early Tertiary plateau basalts (zone I) that occur landward of an escarpment, a flat lying basaltic flow unit immediately seaward of the escarpment (zone II), an elongate wedge of seaward dipping reflectors (zone IIIa), a basaltic flow unit which in places shows seaward dipping beds of short length (zone IIIb), and the oceanic crust.
- Dyke swarms and intrusions of inferred Neogene age were recognized at several locations
Total length of lines | |
Sampling rate | 4 ms |
Record length | 12 000 ms |
Streamer | digital - 48 channels |
References:
K. Hinz, H. Meyer and H. Miller (1991), North-east Greenland shelf north of 79°N: results of a reflection seismic experiment in sea ice. Marine and Petroleum Geology, Vol.8, 461-467.
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Cruise PQ2 1996
Baltic Sea
Vessel Polar Queen
Total length of lines | |
Sampling rate | 4 ms |
Record length | 26 000 ms |
Streamer | digital, 120 channels |
Summary
During the period from 14th to 28th of April 1996 BGR and GFZ chartered the Norwegian vessel M/V POLAR QUEEN for testing the new and updated marine seismic equipment of the BGR and for acquiring seismic lines. The operating area was the North Sea and Baltic Sea.
The geophysical lines in the Baltic Sea were chosen as extended onshore DEKORP lines to evaluate the deep structure of the south western part of the Baltic Sea. For the seismic profiles a tuned source array consisting of 20 air guns in two linear strings with a total volume of 52 l was used. The recording length was 26 s, the sample rate 4 ms and the shot interval 30 s. This time triggering for the shot release was chosen, because all shots were also recorded onshore by seismic stations for wide angle/refraction acquisition (GFZ).
During this leg 810 km reflection lines and additional 230 km pure shooting could be surveyed. The preliminary interpretation of the seismic single traces was restricted on the ship to the upper time range. The main structures in the southern Baltic Sea could be evaluated. A full interpretation especially of the deeper part is only possible after a processing due to the nature of the single traces and the S/N ratio.
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Cruise SO75 1991
Vessel Sonne
OFF Portugal
Total length of lines | |
Sampling rate | 4 ms |
Record length | 12 000 ms |
Streamer | digital, 48 channels |
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Cruise MSM14/2 2010
Vessel MS Merian
OFF Cyprus
Total length of lines | |
Sampling rate | 2, 4 ms |
Record length | 9, 12, 14 s |
Streamer | digital, 312 channels |
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Cruise MSM52 2016
Vessel MSM Merian
Baltic Sea
Total length of lines | |
Sampling rate | 1 ms |
Record length | 9, 10 s |
Streamer | digital, 216 channels |
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