This document only refers to L2 MBES data produced by processing software in the AusSeabed-preferred gsf format (see australian-multibeam-guidelines.github). The L2 MBES data contains processed, full resolution MBES data including status flags (rejected/accepted). We refer to L2 MBES data as a collection of various embedded datasets including raw and processed acoustic soundings and raw ancillary (navigation & attitude etc) datasets, used to make L2 products. L2 data formats in gsf format are strongly recommended to be provided to AusSeabed, unless this cannot be achieved for legitimate reasons.
Table 3. Preferred L2 formats.
Level | Preferred formats | Specifications | |||
Bathymetry | Backscatter | Navigation | Ancillary data |
| |
L2 | Priority 1
| Priority 1
| SBET data + RMS (for generation of TPU) | Priority 1
Priority 2
| When L2 data are provided, also include all L0 data to allow for reprocessing at any stages, if required. L2 should contain data that enable reproduction of L3. Bathymetry and Backscatter Variables: coordinates, depth (m, neg value) or intensity (dB), uncertainty, flag. Coordinate system: Geographic (GDA2020 or WGS84) Precision: Metric variables with minimum of 2 decimals; Angular variables degree decimals with minimum of 6 decimals Navigation and Ancillaries Date and time: Calendar and UTC or specify otherwise Coordinate system: Geographic WGS84 or GDA2020 with an ellipsoidal height datum |
Shape/Geometry format
Format:
Shapefile, or one of the following if this is not possible:
Geography Markup Language (GML)
Well Known Text (WKT)
GeoJson.
AusSeabed will maintain geometries in a spatial format capable of transformation into multiple formats.
Shape specifications
Coordinate Reference System: EPSG:4326 (based on WGS84)
Geometry Type: Line & Polygon (Extent of the Survey from Port to Port)
Purpose/s:
To provide a visual extent of the multibeam survey extents in a mapping portal and
To allow the calculation of a total line kilometres for the Survey.
To allow the calculation of a total area (sq. km) of the multibeam survey extents.
Attributes (Minimum Requirements as listed 4.2.4) – the ‘metadata_url’ is used to link to the more comprehensive attributes and descriptions.
Field Name | Format | Comments |
|---|---|---|
SURV_NAME | Text | Survey Name as supplied by the Contributor |
SURVEY ID | Text | The Survey ID assigned by the Collecting Organisation |
DATA_TYPE | Text | This may be a list of data types collected |
PRIN_INVES | Text | The Principal Investigator/key point of contact |
LICENCE | Text | e.g. CCBY 4.0 |
SURVEY _LINE_KM | Float/Double | The length of the Processed MBES Survey Lines |
AREA_KM2[1] | Float/Double | Area of the polygon extent of the Processed MBES Survey data |
METADATA_URL | Text | Link to Contributing Hub metadata catalogue |
See ASB Procedures for Generating Polygons
LAS
The LAS (LASer) format is a file format designed for the interchange and archiving of lidar point cloud data. It is an open, binary format specified by the American Society for Photogrammetry and Remote Sensing (ASPRS). (see OGC website for specification - https://www.ogc.org/standards/LAS
...
[1] Calculated by projecting to the Australian Lambert Equal Area projection