EDMED Details

General

Dataset Name

Seismic reflection, magnetic and gravimetric survey of Weddell Sea, Antarctica (1991-92)

Data Holding Centre

OGS (Istituto Nazionale di Oceanografia e di Geofisica Sperimentale), Division of Geophysics

Time Period

from 1991 to 1992

Start Date

1991-01-01

End Date

1992-12-31

Project

Geographic Area

Geocoverage

3,393 km on 24 lines of seismic reflection, gravimetric and magnetometric survey of Weddell Sea, divided into the following areas: Area 1 - Hero Fracture Zone: about 2,607 km on 16 lines; Area 2 - Bransfield Strait : about 561 km on 6 lines; Area 3 - Scotia Arc : about 225 km on 2 lines.

Geographic Box (south,north,west,east)

-70, -90, 0, -60

Sea Area

Southern Ocean

Observations

Parameters

Gravity

Seismic reflection

Magnetics

Instruments

multi-channel seismic reflection systems

seismic refraction systems

magnetometers

gravimeters

satellite positioning systems

Description

Summary

PNRA (Italian Research Programme in Antarctica) - During February and March 1992, the OGS carried out an Antarctic Campaign in the seas surrounding the Antarctic Peninsula. The research has been carried out in the framework of the National Research Program in Antarctica coordinated by ENEA under the auspices of the Italian Ministry for Scientific Research. The survey has been dedicated to three different areas where data have been collected with different sampling parameters. The first area of investigation was conducted in the Hero Fracture Zone. In this area, 16 lines have been acquired with 'standard sampling parameters' for a total of 2607 km. The second area investigated during the survey was the Bransfield Strait. Due to the moderate ice coverage and the particular conformation of the area, it was necessary to use a shorter streamer and a reduced airgun array. About 561 km of data along 6 lines have been recorded in this area. In the third area, on the Southern Margin of the Scotia Arc, two lines with a total amount of about 225 km have been acquired. In this area a deep crustal configuration for the streamer was used. This was the first test in which OGS used a very long streamer in Antarctic waters. The characteristics of the data acquisition system were as follows: Area 1 Area 2 Area 3 ------ ------ ------ Coverage = 3000 % 3800 % 4500 % Sample Rate = 4 ms 4 ms 4 ms Shot Interval = 50 m 25 m 50 m Streamer Length = 3000 m 1900 m 4500 m Streamer Depth = 12 m 12 m 12 m Group Interval = 25 m 25 m 25 m Number of Groups = 120 76 180 Record Length = 14 s 7 s 16 s Air-Guns: - Total Volume = 72 l 37.4 l 72 l - Pressure = 140 bar 140 bar 140 bar - Depth = 6 m 6 m 6 m

Originator

OGS (Istituto Nazionale di Oceanografia e di Geofisica Sperimentale), Division of Geophysics

References

Availability

Availability

by negotiation

Organization

OGS (Istituto Nazionale di Oceanografia e di Geofisica Sperimentale), Division of Geophysics

Contact

unknown

Address

OGS (Istituto Nazionale di Oceanografia e di Geofisica Sperimentale), Division of Geophysics

Sgonico (Trieste),

34010

Italy

webmaster@ogs.trieste.it

http://www.ogs.trieste.it

Administration

Local identifier

1235

Creation Date

2014-10-02

Revision Date

2013-07-26