Reflection seismic, magnetic, gravimetric survey of the Pacific Margin of the Antarctic Peninsula (Summer 1989-90, 1991-1992)

The first area of investigation interested 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 is the Bransfield Strait.

Due to 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, 2 lines for 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 to use a very long streamer in Antarctic waters. The characteristic of data acquisition system were as follows: AREA1 AREA2 AREA3 (HERO FRACTURE ZONE) (BRANSFIELD STRAIT) (SCOTIA ARC) (62S, 69S, 61W, 79W) (62S, 64S, 57W, 63W) (60S, 62S, 50W, 52W) Coverage 3000 % 3800 % 4500 % Record Length 14 sec 7 sec 16 s Sample Rate 4 ms 4 ms 4 ms Shot Interval 50 m 25 m 50m Streamer Length 3000 m 1900 m 4500 m Streamer Depth 12 m 12 m 12 m Number of Groups 120 76 180 Group Interval 25 m 25 m 25 m Air-Guns - Total Volume 45.16 1 37,4 1 72 1 - Pressure 140 bar 140 bar 140 bar - Depth 6 m 6 m 6m Source Name:Research Vessel > OGS-Explora Sensor Name:ASTR1>Analogic streamer, Prakla Sensor Name:MSREC1>Multichannel seismic recorder,Sercel 358 Sensor Name:BGV2>Gravimetric Bodenseewerk, KSS31 Sensor Name:GMG1>Magnetometer Geometrics, G801-803