Processed seismic data of Cruise BGR91 1991

The BGR 1991 cruise with M.V. BIN HAI 511 was designed to study the variability of the oceanic crustal structure along flow-line profiles perpendicular to the ridge axis over Early Tertiary through Cretaceous old oceanic crust of the eastern Atlantic Ocean. Seismic data with a coverage of 3,000 % were acquired along four flow-line profiles with a total length of 4,194 km, and in addition 270 km of MCS data were collected during the period from 2nd October to the 3rd November 1991. The most intriguing new observation from the seismic flow-line profiles is the discovery of two huge oceanic crustal structures characterized by an internally divergent to planar pattern of reflectors having ubiquitous seaward dip. These remarkable structures were found within an about 1,300 km long oceanic crust segment of the eastern South Atlantic located between the Bode Verde Fracture zone in the north and the Rio Grande Fracture Zone in the south. These structures resemble the prominent wedges of seaward dipping reflectors on the widespread volcanic rifted continental margins described in the literature. They are interpreted to represent voluminous build-ups of layered extrusive rocks formed during three excessive episodes of volcanism that accompanied the Cretaceous opening of the South Atlantic. These episodes of excessive volcanism/magmatism are: An episode immediate prior to, and during the first stage of seafloor spreading in the South Atlantic, i.e. during about Hauterivian through about early Aptian; an episode of inferred subaerial and/or shallow marine volcanism along the central South Atlantic spreading ridge during the Albian; and an episode of inferred subaerial and/or shallow marine volcanism along the South Atlantic spreading ridge during latest Cenomanian/earliest Turonian through early Campanian.

Citation proposal
. Processed seismic data of Cruise BGR91 1991. https://gdk.gdi-de.org/geonetwork/srv/api/records/90e51e5d-551b-4a84-900d-10ed5d90ba9f

Simple

Alternate title: BGR91 1991

Date ( Creation ): 1991-11-03

Identifier: 9159b25b-42a2-6fbb-9c74-95abb96b64df

Status: completed Completed

Point of contact

Federal Institute for Geosciences and Natural Resources

Stilleweg 2 Hannover 30655

GEMET - INSPIRE themes, version 1.0 ( Theme )

Geologie
geology

GEMET - Concepts, version 2.4 ( Theme )

geophysics
Geophysik
raw material
Rohstoff

Keywords ( Theme )

Marine geology
Meeresgeologie
Seismics
Seismik
Two-dimensional seismic reflection
zweidimensionale Reflektionsseismik

Keywords ( Place )

West Africa
Westafrika
Angola Basin
Angola-Becken
Namibia
Südatlantik
South Atlantic Ocean

Access constraints: Other restrictions

Use constraints: Other restrictions

Other constraints: Allgemeine Geschäftsbedingungen, siehe http://www.bgr.bund.de/AGB - General terms and conditions, see http://www.bgr.bund.de/AGB_en. Die bereitgestellten Informationen sind bei Weiterverwendung wie folgt zu zitieren: Datenquelle: BGR91 1991, (c) BGR, Hannover, 1991

Spatial representation type: Vector

Metadata language: English

Character set: UTF8

Topic category

Geoscientific information

Distribution format

Shapefile (n/a )

Transfer size: 2

OnLine resource: BGR91 1991 (Shapefile)
BGR91 1991 im Format ESRI Shape

OnLine resource: Karte im BGR-Geoviewer
Karte im BGR-Geoviewer

Hierarchy level: Dataset

Conformance result

Date ( Publication ): 2010-12-08

Explanation: siehe dazu die angegebene Durchführungsbestimmung

Statement: During the period from the 2nd October to the 3rd November 1991 BGR acquired seismic lines off West Africa and in the Angola Basin. The lines BGR91-01, BGR91-02, BGR91-03, BGR91-04 and BGR91-06 are raw data. The lines BGR91-02A and BGR91-05 are processed (migrated) data.