Processed seismic data of Cruise BGR78-2 1978

During the second leg of cruise BGR78 from 22th of February to 29th of March 1978 with R/V EXPLORA the following measurements have been carried out as presite- and postsite surveys of DSDP sites: (1) in the region of the eastern Walvis Ridge 4,350 km multichannel seismic reflection profiles, 4,540 km magnetic measurements, 5,000 km gravimetric measurements and sonobuoy refraction measurements on 11 stations (2) on the Guinea Plateau 740 km multichannel seismic reflection profiles in parallel with gravimetric and magnetic measurements (3) between Cape Verde islands and Mauretania 980 km multichannel seismic reflection profiles in parallel with magnetic measurements, 1,480 km gravimetric measurements and sonobuoy refraction measurements on 2 stations. The geophysical measurements show that the structure of the Walvis Ridge is determined by two main tectonic directions (WSW-ENE and SSW-NNE). Presumably the genesis of the fracture zone in the Walvis Ridge area can be traced back to the sea-floor spreading with overprinting effects due to an inhomogeneity in the mantle ("hot spot"). Both DSDP drilling projects in this part of the Walvis Ridge led to a fragmentary knowledge because site 362 got stuck at a depth of 1.100 m in the Oligocene. BGR's measurements indicate a gap of at least 1.000 m of sediments, especially from the cretaceous period, down to the (acoustic) basement. Site 363 at a submarine high has gaps in the depositional sequence and stops at a depth of 700 m shortly above the basement. So for a better understanding of the geologic development of the Walvis Ridge, further DSDP drillings with a recovery of the complete sedimentary sequence and the following basement cores are necessary. Therefore BGR's measurements of this cruise propose new DSDP sites.

Citation proposal
. Processed seismic data of Cruise BGR78-2 1978. https://gdk.gdi-de.org/geonetwork/srv/api/records/96dcdd10-3847-428b-bd2d-b4c93e169b21

INSPIRE
SDS

INSPIRE

Identification

File identifier: 96dcdd10-3847-428b-bd2d-b4c93e169b21 XML

Hierarchy level: Dataset

Online resource

Resource identifier

code: d0582412-d868-16e2-9833-167140819201

Metadata language: English

Spatial representation type: Vector

Encoding

Format: Shapefile

Version: n/a

Projection

Classification of data and services

Topic category

Geoscientific information

Classification of data and services

Coupled resource

Classification of data and services

Coupled resource

Keywords

GEMET - INSPIRE themes, version 1.0 ( Theme )

Geologie
geology

GEMET - Concepts, version 2.4 ( Theme )

geophysics
Geophysik
raw material
Rohstoff

Other keywords

Keywords ( Theme )

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

Keywords ( Place )

Walvis Ridge
Walvis-Rücken
Guinea Plateau
Mauretania
Mauretanien
Southeast Atlantic Ocean
Südost-Atlantik

Geographic coverage

Temporal reference

Temporal extent

Date ( Creation ): 1978-03-29

Quality and validity

Lineage: During the period from 22th February to 29th March 1978 BGR acquired seismic lines in the Southeast Atlantic Ocean across the Walvis Ridge and the Guinea Plateau and off Mauretania during the second leg of cruise BGR78. The lines BGR78-127, BGR78-137 and BGR78-148 consist of raw data. The lines BGR78-128, BGR78-129, BGR78-130, BGR78-131, BGR78-132, BGR78-133, BGR78-134, BGR78-134A, BGR78-135, BGR78-136, BGR78-138, BGR78-139, BGR78-140, BGR78-141, BGR78-145, BGR78-146, BGR78-149, BGR78-150 and BGR78-151 are stacked data.

Conformity

Explanation: siehe dazu die angegebene Durchführungsbestimmung

Restrictions on access and use

Access 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: BGR78-2 1978, (c) BGR, Hannover, 2019