Geological Long Range Inclined Asdic (GLORIA) seabed side-scan sonar raw data acquired on Charles Darwin CD37 cruise in 1989

We present here side scan sonar datasets and accompanying quicklook seabed images of the Scotia Sea acquired by a GLORIA II (Geological Long Range Inclined Asdic) side scan sonar. The GLORIA instrument was operated on the Royal Research Ship (RRS) Charles Darwin 37 (CD37) research cruise during January - April 1989. The study area was the Scotia Sea, North Scotia Ridge (NSR), South Sandwich Island, South Sandwich Arc, and West Antarctic Peninsula (WAP) continental shelf, within the broader region of the Southern Ocean.

Raw data are presented in NetCDF format. These have been pre-processed from the binary pass data using the bas-gloria package ( https://github.com/antarctica/bas-gloria). The data have been improved with additional metadata such as latitude, longitude and depth. In addition, "quicklook" seabed images generated from each pass file are provided as PNG images. Cruise tracks from the ship and side scan sonar are presented in CSV format.

The cruise was carried out in order to gain a better understanding of the Southern Ocean with a particular focus on:

- Tectonic history

- Active tectonic processes

- Paleoceanography

- Stratigraphy

- Ice dynamics during glacial intervals

This project was funded by BAS under project code B6153: Scotia Sea tectonic evolution and palaeo-circulation.

Alternate title: Polar Data Centre (PDC) record GB/NERC/BAS/PDC/02004

Date (Publication): 2025-02-18

Citation identifier: http://www.antarctica.ac.uk/dms/metadata.php?id= / GB/NERC/BAS/PDC/02004

Point of contact

Organisation name	Individual name	Electronic mail address	Role
British Antarctic Survey		pdc@bas.ac.uk	Custodian
NERC EDS UK Polar Data Centre	Barker, P., Livermore, R., Tomlinson, J., Woollett, R., Cunningham, A., Larter, R., Pudsey, C., & Jordan, R.	pdc@bas.ac.uk	Originator

Maintenance and update frequency: Unknown

Keywords

NDGO0001

NERC OAI Harvesting

NERC_DDC

GCMD Parameter Valids

EARTH SCIENCE > Oceans > Bathymetry/Seafloor Topography
EARTH SCIENCE > Oceans > Marine Geophysics
EARTH SCIENCE > Oceans > Ocean Acoustics

BAS Free-text keywords

Antarctica
GLORIA
Southern Ocean
marine geology
marine geophysics
sidescan sonar

Use limitation: Data supplied under Open Government Licence v3.0 http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/.

Access constraints: Other restrictions

Other constraints: Data supplied under Open Government Licence v3.0 http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/.

Language: English

Topic category

Geoscientific information
Oceans

Begin date: 1989-01-04

End date: 1989-04-02

Reference system identifier: OGP / urn:ogc:def:crs:EPSG::4326

Distribution format

Distributor contact

Organisation name	Individual name	Electronic mail address	Role
Polar Data Centre - British Antarctic Survey		pdc@bas.ac.uk	Distributor

OnLine resource

Protocol	Linkage	Name
http		GET DATA

Hierarchy level: Dataset

Domain consistency

Measure identification: INSPIRE / Conformity_001

Conformance result

Title: INSPIRE Data Specification on unknown theme Guidelines

Date

Explanation: See the referenced specification

Pass: No

Statement: In the initial data recovery, PASS245 was long and PASS246 was missed. This was determined to be caused by a reading error, resulting in concatenation of consecutive data from PASS246 to PASS245. These passes were then read from tape separately, and are now considered complete.

In the recovered raw data, some passes were missing: PASS039, PASS040 and PASS231. Copies of these data held at BODC were provided in CDF format, which were converted to NetCDF. These passes are now considered complete. As the CDF files did not contain data for the slant range correction code, zero flag, hour mark flag and unused attributes (which were determined to be non-significant in the recovered raw data), a NaN value of 9999 has been used in the converted files for these passes. In addition, it is to be noted that PASS038, PASS227 and PASS236 are partially complete,

To get the latitude and longitude of GLORIA related to the ship, a fixed 90 second time offset was added to the ship track datetime to account for tow distance of the GLORIA instrument behind the ship (the output of this was the GLORIA track CSV). The latitude and longitude of the GLORIA track was then interpolated to provide the value of these coordinates at the original datetime of the ship track. This was done in order to map geographic information to the timestamps within the netCDF metadata. Interpolation on the latitude and longitude fields from ship track data was done with the Pandas Python library.

Depth values within the NetCDF file metadata are provided by the International Bathymetric Chart of the Southern Ocean (IBCSO) version 2. Due to the resolution of IBCSO, the depth in the GLORIA NetCDF metadata is provided with a horizontal resolution of 500x500m, leading to some positive values close to coastline areas.