Abstract

This dataset provides the spatially continuous data of seabed gravel (sediment fraction >2000 µm), mud (sediment fraction < 63 µm) and sand content (sediment fraction 63-2000 µm) expressed as a weight percentage ranging from 0 to 100%, presented in 0.0025 decimal degree (dd) resolution raster grids format and ascii text file. The dataset covers the Vlaming sub-basin in the Australian continental EEZ. This dataset supersedes previous predictions of sediment gravel, mud and sand content for the basin with demonstrated improvements in accuracy. Accuracy of predictions varies based on density of underlying data and level of seabed complexity. Artefacts occur in this dataset as a result of insufficient samples in relevant regions. This dataset is intended for use at the basin scale. The dataset may not be appropriate for use at smaller scales in areas where sample density is insufficient to detect local variation in sediment properties. To obtain the most accurate interpretation of sediment distribution in these areas, it is recommended that additional samples be collected and interpolations updated.
Google map showing geographic bounding box with values North bound -29.751141 East bound 115.77348 West bound 113.75098 South bound -34.251141
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please contact Geoscience Australia Client Services via:

fax:
+61 2 6249 9960; or
phone:
1800 800 173 (within Australia);
 
+61 2 6249 9966 (outside Australia).

Product Type/Sub Type

dataset - Data Package

Constraints

license
Creative Commons Attribution 3.0 Australia Licence

IP Owner

Commonwealth of Australia (Geoscience Australia)

Author(s)

Date (publication)

2014

Product Type

dataset

Topic Category

geoscientificInformation

Keywords

Data Package
Earth Sciences

Resource Language

English

Resource Character Set

utf8

Resource Security Classification

unclassified

Geographic Extent

North bound
-29.751141
East bound
115.77348
West bound
113.75098
South bound
-34.251141

Lineage

Sediment samples were exported from Geoscience Australia's Marine Sediments database (MARS), an Oracle database developed by Geoscience Australia in line with ANZLIC data standards. A subset of this data was selected for use in predicting spatial distribution of gravel, mud and sand content based on a set of data quality control criteria (see Li et al. 2010 and 2012). Predicting the spatial distribution of gravel, mud and sand content at a 0.0025 decimal degree resolution was undertaken using a combined method of random forest and ordinary kriging (see Li et al. 2010, 2011 and 2012). The spatial interpolation method used was experimentally selected from over 40 methods/sub-methods based on assessment of predictive errors (Li et al. 2010, 2011 and 2012) and was refined for gravel, mud and sand respectively based on further experimental testing during March 2013. The predictions in raster grids and ascii text file were generated in R. Final file is in WGS 84 coordinate system with a 0.0025 dd spatial resolution. File sizes are approximately 22 MB (raster grids) and 50 MB (ascii text) for each sediment type (i.e., gravel, mud and sand), with data dimensions of 1800 (row) x 809 (column) and 1456200 (cell).

Digital Transfer Options

onLine

DISTRIBUTION Format

misc
unknown

Distributor

Role
distributor
Organisation Name
Geoscience Australia
City
Canberra
Administrative Area
ACT
Postal Code
2601
Country
Australia
Email Address

Metadata File Identifier

f70f8705-763d-32a0-e044-00144fdd4fa6

Metadata Standard Name

ANZLIC Metadata Profile: An Australian/New Zealand Profile of AS/NZS ISO 19115:2005, Geographic information - Metadata

Metadata Standard Version

1.1

Metadata Date Stamp

2014-04-15

METADATA SECURITY CLASSIFICATION

unclassified

Metadata Contact

Role
pointOfContact
Organisation Name
Geoscience Australia
City
Canberra
Administrative Area
ACT
Postal Code
2601
Country
Australia
Email Address
Downloads
For information on acquiring this product,
please contact Geoscience Australia Client Services via:

fax:
+61 2 6249 9960; or
phone:
1800 800 173 (within Australia);
 
+61 2 6249 9966 (outside Australia).